The Foot

The term “clubfoot” refers to a congenital foot
deformity characterized by equinus of the hindfoot and adduction of the
midfoot and forefoot with varus through the subtalar joint complex (Fig. 30.6). There is also a cavus deformity

through the midfoot, which accompanies most clubfeet. In identifying the pathologic tissue in a clubfoot, Irani and Sherman (14) found the talus to be uniformly abnormal, and a group led by Clarke (15)
demonstrated malformation of the calcaneus. In addition, however, those
who have looked at the tissue surrounding the bones have identified
vascular abnormalities, muscle lesions, abnormal muscle insertions, and
retracting fibrosis to be associated pathologic abnormalities in
clubfoot deformity. The pathology clearly is not limited to the osseous
structures. Clubfeet in general are “idiopathic,” occurring in
otherwise healthy children. Some are positional, with rapid correction
and requiring little by way of treatment. On the other extreme of the
spectrum of clubfeet are those associated with syndromes such as
Freeman-Sheldon syndrome and arthrogryposis, in which there is a rigid
clubfoot with fibrotic muscles and little in the way of active muscle
function. Idiopathic clubfoot bridges the spectrum between these two
conditions.

The incidence of clubfoot varies from a baseline occurrence of 0.6 per 1000 in Asian populations (16, 17, 18) and 0.9 per 1000 births in western Australia (19) to a high of 6.8 per 1000 in Hawaiians, Polynesians, and Maoris (20).
Boys are affected more than girls in all studies, varying from a
twofold increased incidence to a high of 4:1, depending on the
population studied. Bilateral involvement is present in approximately
50% of cases (17,21).

Wynne-Davies (17,18)
determined that the occurrence rate was 17 times higher than in the
normal population for first-degree relatives and six times higher for
second-degree relatives. Unaffected parents with an affected son have a
2.5% chance of another child having the disorder. If the affected child
is a girl, then there is a 6.5% chance of a son having clubfoot and a
2.5% chance of a subsequent daughter being affected. Wynne-Davies
proposed dominant inheritance with reduced penetrance or multifactorial
inheritance to describe this pattern of occurrence.

Cowell and Wein’s data (21) suggested multifactorial inheritance. Skelly et al. (22) demonstrated the effect of maternal smoking during pregnancy in increasing the risk of clubfoot. Honein et al. (23)
also identified maternal smoking as a significant factor in etiology.
The joint effect of family history of clubfoot and maternal smoking
during pregnancy was more than additive, suggesting a
genetic-environmental interaction. Rebbeck et al. (24), using a complex mathematical model, concluded that the inheritance of clubfoot could be explained as a single-gene defect.

In a clubfoot, the navicular is subluxated medially and
plantarward on the head of the talus. In severe cases, the navicular
may actually articulate with the medial malleolus. The talus is
shortened, with medial deviation of its head and deformity of the talar
neck, but the long axis is actually laterally deviated in the mortise,
as shown by Carroll and Hertzenberg (25). The
sheath of the posterior tibial tendon and the calcaneonavicular
ligament are shortened and thick, contributing to medial deformity.
Posterolaterally, the calcaneofibular ligament is also shortened and
thickened, causing medial spin of the calcaneus in clubfoot. Deep
posterior and medial skin creases are universally present in a clubfoot
(Fig. 30.7).

The muscles are abnormal both in anatomical insertion and intrinsic structure (26,27).
Muscles in clubfoot are smaller than normal and there is an increase in
intracellular connective tissue within the gastrocsoleus and posterior
tibial muscles. A predominance of type I muscle fiber has been seen in
posterior and medial muscle groups. Electron microscopic studies have
shown loss of myofibrils and atrophic fibers, suggesting a regional
neuronal abnormality as well (25).

The ligaments are thick, with increased collagen fibers and increased cellularity (28). This is particularly true of the calcaneonavicular ligament or spring ligament and the posterior tibial tendon sheath (29).
An electron microscopic study of medial ligaments in clubfoot
identified myofibroblasts, which could be responsible for fibroblastic
contracture in the postoperative clubfoot. Fukuhara et al. (30)
showed myofibroblastlike cells in the deltoid and spring ligaments.
Together, the thickened and shortened ligaments with contractile
fibroblasts may produce a significant component of the clubfoot
pathology. Sano et al. (31) confirmed these
findings, showing that cells of the medial ligamentous structures
contained vimentin uniformly and myofibro-blasts in some cases. More
recently, Khan et al. (32) were unable to show myofibroblastlike cells in clubfeet, and van der Sluijs and Pruys (33) demonstrated normal collagen cross-linking in clubfeet.

Finally, abnormal vasculature in the foot is frequently present (34). The dorsalis pedis artery in a number of cases is absent or altered. Katz et al. (35)
showed deficient dorsalis pedis flow in 45% of clubfeet compared to 8%
of normal controls. In the more severely affected feet requiring
surgery, the incidence of dorsalis pedis abnormality was 54%, whereas
those successfully treated with cast therapy had an abnormality in
dorsalis pedis flow in only 20% of cases. This data suggests that the
severity of clubfoot may in some way relate to the vascular abnormality
frequently seen in this condition.

There is no consensus on the role of radiography in the diagnosis and management of clubfoot (36,37).
The diagnosis is made in the newborn child based on clinical findings
of equinus of the hindfoot with some degree of varus and medial
deviation. There is little ossification in the bones of the healthy
foot of the newborn, whereas delay in ossification in the clubfoot has
been documented (38). The ossific nucleus of
the talus is not centrally located, further compromising the validity
of x-ray evaluation of clubfoot (39,40).
Ossification of the navicular does not occur until the age of 3 to 4
years in children with clubfoot and may be eccentric. Brennan et al. (41)
documented poor reproducibility of x-ray films in a child with clubfoot
because of problems with positioning, in addition to the unusual shape
of the ossification center as it develops.

Despite these limitations, x-ray evaluation of clubfeet is helpful in determining surgical planning (42, 43, 44).
The anterioposterior view is obtained with the foot pressed against a
radiographic plate. In taking this view, the foot is dorsiflexed
maximally and held in a position of external rotation (37,45) (Fig. 30.8).
The talus to first metatarsal angle is measured on both the
anteroposterior and lateral views, with increasing angles indicating
more severe deformity. As the navicular is not ossified, there is no
direct measurement of the position of this bone relative to the long
axis of the talus (46). The axis of the talus
and the calcaneus usually converge, and the axis of the talus and the
first metatarsal form a straight line in the healthy state. The degree
of divergence from this linear alignment represents the intrinsic
deformity of the clubfoot (46). With
dorsiflexion, the long axis of the talus and the calcaneus remain
parallel, and the calcaneus remains plantar-flexed relative to the long
axis of the talus (Fig. 30.8). The alignment of the calcaneus and the cuboid is assessed on the anterioposterior view.

Radiography may also be helpful in the intraoperative
evaluation of the correction of clubfoot deformity. The difficulty in
the intraoperative measurement is in reproducibly holding the foot in
the right position for imaging. Intraoperative radiography remains
controversial in the management of clubfoot deformity.

Clubfoot deformity has also been measured by computed
tomography (CT) scan, magnetic resonance imaging (MRI), and ultrasound.
These different techniques of measurement have demonstrated
conclusively a shortened longitudinal axis with medial deviation of the
talar neck. However, the longitudinal axis of the talus is laterally
rotated within the mortise. The calcaneus is internally rotated with
decreased space between the calcaneus and the fibula posteriorly. The
navicular is dislocated plantarward and medially on the head of the
talus, as shown by ultrasound and MRI evaluation.

An examination of the patient with clubfoot should
include looking for spinal pathology, neurologic abnormality, and any
syndrome or associated condition in which clubfeet is frequently found (Table 30.1).
Clubfoot is associated with a small calf on the ipsilateral side and a
slightly shortened tibia. A minimal tibial length discrepancy is
present at birth, but Spiegel and Loder (47) found it to be greater than

0.5 cm in 32 of 47 patients who were affected at maturity. Along with a
shortened tibia, internal tibial torsion is occasionally associated
with clubfoot deformity.

Muscle testing and sensory examination should be part of
the initial examination in all patients, as clubfoot has been found to
be associated with absent anterior compartment muscles and lesions
involving the innervation to the anterior and lateral compartment
muscles.

With respect to classification of clubfeet, important clinical features must be documented. Included in these features are:

Although there are a number of classification systems in
use, the author finds two of them to be of particular value in
attempting to classify clubfeet at the initiation of treatment. One of
these classification systems was defined by Dimeglio et al. (48) and the second by Pirani (49).
The classification systems apply a point score to a number of physical
findings, which when totaled leads to a “grade of involvement.” Flynn
et al. (50) have shown a good correspondence between the classification systems of Pirani and Dimeglio. Flynn and MacKenzie (50)
showed a correlation coefficient of 0.9 with the Pirani system and 0.83
with the Dimeglio system when applied by three individuals. The
correlation improved in both systems after the initial 15 feet were
scored. Wainwright et al. (51) compared four
classification systems: Dimeglio, Catteral, Harold and Walker, and
Ponseti and Smoley, determining that the Dimeglio system was the most
reproducible. Both the Dimeglio and the Pirani point systems attempt to
differentiate between mildly affected feet requiring little treatment
and those that are extremely severe. If outcome of treatment is to be
compared, a valid classification system at the onset of therapy must be
developed.

The author uses the Dimeglio system in everyday
practice. One should create a checklist with either of the systems and
attempt to score feet at the initiation of treatment. Either of the
scoring systems can be applied in less than 5 minutes. In the Pirani
system, isolated physical findings such as space between the medial
malleolus and navicular, and space between the calcaneus and the
fibula, are identified and given scores on a 0, 0.5 or 1.0 basis. In
the Dimeglio system (Fig. 30.9), the position
of the foot deviation—whether equinus, varus, or medial—is scored based
on the degree of deformity, as well as muscle function and depth of
skin creases. The author

believes
that the isolated physical findings in the Pirani classification will
correlate directly with the gross foot position data in the Dimeglio
classification, leading to the correlation found by Flynn and others in
applying these systems. Choose one and attempt to grade clubfeet, on
the basis of these clinical criteria.

With the routine use of ultrasonography during
pregnancy, intrauterine diagnosis of clubfoot has become increasingly
frequent. This has implications, requiring the orthopaedist to be able
to provide informed consultation concerning the long-term outcome of
the deformity, as well as its proposed

treatment.
The orthopaedist must possess knowledge of the accuracy of diagnosis,
its relation to syndromes, and the treatment regimes need in order to
have an informed discussion with the prospective parents. It appears
that the earliest that a clubfoot can be diagnosed by ultrasound with
accuracy is 12 weeks of gestational age. With sequential studies, there
is an increased ability to visualize the deformity, relating either to
the progressive development of a clubfoot deformity or perhaps the
accuracy with which it can be seen. According to Keret et al. (52),
the clubfoot deformity has been detected in routine studies in
approximately 60% of cases, which is indicative of some degree of false
negative assessment. In 86% of cases, the deformity is identified by 23
weeks of gestational age, but still others are recognized up to 33
weeks. The diagnosis is made on ultrasound by the fixed position of the
foot in an equinovarus position, not deviating from this on sequential
observations (Fig. 30.10). Three-dimensional ultrasound may provide a more accurate diagnosis than standard ultrasound studies (53).

In studies of large populations using routine in utero ultrasound (54), the recognition of clubfoot deformity varies from 0.1% to 0.4% (55).
Because postnatal studies suggest an occurrence rate at birth between
0.1% and 0.6%, one can assume a rather low false negative rate. The
false-positive rate for diagnosis of clubfoot in utero using ultrasound varies from 30% to 40%, depending on series and criteria (55, 56, 57, 58). A term functional false-positive rate
has been used in cases in which a foot may have the appearance of
remaining in a plantar flexed, varus and medially deviated position but
can passively be corrected to neutral during exam just following birth.
The foot is characterized with a score of 0, 1, or 2, using the
Dimeglio classification system. Such a foot requires only
parent-administered exercise, and no long-term deformity results. With
the advancement of ultrasound and increase in experience, the accuracy
of diagnosis will steadily increase.

The ability to recognize syndromes associated with skeletal malformations is also increasing with time (53,59).
The combination of technologic advances and improved expertise in
obtaining and interpreting images will certainly lead to further
progress in recognizing fetal structural abnormalities. This brings one
to the question of the need for amniocentesis and karyotyping if an
isolated clubfoot deformity is found. In 1998 Shipp and Benacerraf (60) and Rijhsinghani et al. (55)
suggested that amniocentesis and karyotyping were necessary to identify
associated syndromes when clubfoot was identified. In 2000, Malone et
al. (61) showed that in 57 cases of isolated
clubfoot deformity out of 27,000 prenatal exams, there were no
unrecognized associated abnormalities. Therefore, the recommendation is
that karyotyping not be done in cases where a diagnosis of isolated
clubfoot deformity was made. This still appears controversial, and a
geneticist should be consulted about the need for amniocentesis if the
question arises.

There is no attempt to provide any therapeutic
intervention once an intrauterine diagnosis of clubfoot is made. The
orthopaedist is only involved in counseling the family and providing
treatment following birth. The author has found that this information
allows for an informed discussion with the pregnant mother and
interested father about the treatment and outcome in clubfoot
deformity. The parents can be comforted by being shown the successful
outcome after treatment of patients with this deformity. Myths about
the crippling effect of clubfoot deformity can be dispelled. Accurate
information about treatment and outcome allow the parents to make a
personal decision concerning pregnancy and allows for an improved
emotional state for the family during the delivery of their child.

Metatarsus adductus is the most common foot deformity of
infancy and is characterized by medial deviation of the forefoot on the
hindfoot (Fig. 30.17). The deformity in its
mildest form resolves spontaneously, has no rigidity, and is of little
clinical significance. In its more severe form, it may be associated
with pain and difficulty wearing shoes, and hence requires treatment.

Wynne-Davies (17) reported the
incidence of metatarsus adductus to be 1 per 1000 live births, with an
increased incidence with positive family history. This is a significant
variation from the data of Hunziker et al. (124),
who found an overall frequency of metatarsus adductus at 12%, with even
higher incidence in twin births. As there is increased awareness of
this condition and increased reporting, higher frequencies are recorded
(125, 126, 127). Although historically this has been associated with hip dysplasia (128,129), recently no association between hip dysplasia and metatarsus adductus has been found (130,131). Therefore, there is no indication for ultrasound screening of hips in infants when this deformity exists.

The true cause of metatarsus adductus remains unknown. Fetal studies by Morcuende and Ponseti (132)
have documented an alteration in the medial cuneiform in association
with metatarsus adductus without joint subluxation or tendon
abnormalities. Reimann and Werner (133)
suggested that the primary abnormality in metatarsus adductus was
subluxation of the tarsal metatarsal joints in addition to cuneiform
abnormality (133). The possibility of muscle
contracture, with imbalance between the anterior and posterior tibial
tendons and abnormal insertion of the anterior tibial tendon, has been
suggested (126, 134, 135, 136). An abnormally shaped cuneiform (137) may play a role in persistent metatarsus adductus (Fig. 30.18).

Medial deviation of the forefoot in metatarsus adductus
is the hallmark of this condition. There is prominence of the proximal
fifth metatarsal laterally. The hindfoot is generally in neutral and
forefoot slightly supinated. A deep medial crease is usually present.

There are two clinical classification systems published by Bleck (138,139) to define this condition. One is known as the heel bisector (Fig. 30.5)
in which the feet are placed on a photocopy machine and the axis of the
heel is projected through the forefoot or a similar line is drawn on
the plantar surface of the foot. The heel bisector moves laterally
across the toes with increasing severity of the condition. The second
classification (Fig. 30.19) (138)
defines metatarsus adductus based on flexibility. By holding the heel
with a thumb providing a fulcrum over the fifth metatarsal head,
pressure is applied laterally to the forefoot. The degree to which the
lateral border of the foot can be corrected determines the flexibility
of the foot.

Radiographs are in general not necessary in classification and treatment of metatarsus adductus. Although Berg (140)
developed a classification system for metatarsus adductus and skewfoot
based on radiographs in a small group of children, Cook et al. (141)
found that classification system to have high interobserved and
intraobserver error. Given that the natural history of this condition
is one of spontaneous resolution, simply documenting the clinical
deformity and observing for spontaneous resolution is a generally
accepted routine. Radiographs are indicated for patients with
persistent deformity. A standing or simulated weight-bearing view will
demonstrate a trapezoidal shape to the medial cuneiform

and medial deviation of the metatarsals (Fig. 30.18).
This can be differentiated from skewfoot, in which lateral subluxation
of the navicular is a hallmark on the anteroposterior view. When the
navicular is not ossified, the long axis of the first metatarsal is
translated laterally relative to the talus.

As internal rotation gait is a common parental complaint
in the older child, a contribution of internal tibial torsion and
femoral anteversion in addition to metatarsus adductus should be noted
on physical examination and clearly documented. The natural history of
each of these deformities will then contribute to the spontaneous
resolution or persistence of the intoeing deformity.

The prognosis for spontaneous correction in flexible metatarsus adductus is excellent (2,3,134).
Although passive stretching exercises are commonly recommended, their
efficacy has not been clearly demonstrated. Ponseti and Becker (3) noted potential harm in increasing hindfoot deformity by overzealous treatment.

Bleck (138), Berg (140)
and Ponseti have demonstrated efficacy in manipulation and serial
casting in resolution of metatarsus adductus that is either partially
flexible or inflexible. Best results from corrective casting occur in
patients younger than 1 year at initiation of therapy (3,138,140). In the use of corrective casting, there is some risk of increasing hindfoot valgus or producing an iatrogenic skewfoot (3,126).
One way in which the risk of hindfoot valgus can be decreased in
corrective casting for metatarsus adductus is by plantar-flexing the
foot slightly to lock the subtalar joint. Postcast splinting may be
used to decrease the rate of recurrence, which has been reported as
occurring in between 8% and 37% of cases (126,138,142).

The role for casting tends to be in children between 6
months and 1 year of age. In children younger than 6 months, gentle
exercises are advocated with use of a reverse-last shoe or Bebax shoe
at times to maintain correction.

Surgical treatment of persistent metatarsus adductus is rarely indicated (2). Spontaneous resolution of minor residual deformity may occur until 3 or 4 years of age (2,3). It should also be noted that minor residual deformity carries with it no significant disability in most cases (2,4).
In select cases in which the deformity has a primary component of
medial deviation of the great toe, release of the abductor hallucis has
been advocated; it should be noted that this may result in the
development of hallux valgus (143). Medial capsulotomies have been reported in treatment of this deformity (144). Heyman et al. (145)
described treatment using forefoot capsulotomy of the tarsometatarsal
joints with release of intermetatarsal ligaments. Long-term studies (146,147),
however, have shown a 41% failure rate, with complications including
skin slough and pain with prominence of the tarsal metatarsal joints.

Osteotomies of the base of the metatarsals have been
used as a beneficial extraarticular alternative, avoiding the
complications of capsulotomies (148,149).
The greatest risk in this procedure, however, is growth arrest of the
first metatarsal from physeal injury, noted in a significant number of
patients treated in this manner (148,150,151).

In the rare situation of an older child with significant
disability from metatarsus adductus, a combination osteotomy including
closing wedge of the cuboid and opening wedge of the first cuneiform
has been advocated (152) (Fig. 30.20).
As the primary deformity in metatarsus adductus is a trapezoid-shaped
first cuneiform in most cases, this procedure is most appealing. It
treats the deformity where the pathology is, and carries no risk of
growth arrest to the first metatarsal. It has been described with
removal of a lateral wedge from the cuboid with insertion into the
first cuneiform. The author has found the wedge from the cuboid to be
of insufficient substance to provide sufficient strength as a spacer in
the opening wedge of the cuneiform; allograft appears to be a

better
choice. In severe cases, the cuboid-closing osteotomy and
cuneiform-opening osteotomy can be combined with osteotomies of the
second, third, and fourth metatarsals at their bases, to provide better
correction (153, 154, 155, 156).

Skewfoot is a term indicative of a complex foot
deformity combining medial deviation of the forefoot, lateral
translation of the midfoot, and valgus hindfoot into one condition (Fig. 30.21).
The recognition of the multiplanar abnormalities in this deformity is
critical to its appropriate treatment. In the past, inconsistent
terminology has been applied to this, including congenital metatarsus
varus (136) or serpentine metatarsus adductus (125). Mosca (102,157,158) defined the skewfoot with a significant valgus hindfoot (Fig. 30.22) as a major component of this deformity.

Given the lack of definition and complexity of
terminology relative to this deformity, not to mention its rarity, the
pathogenesis, natural history, and treatment remain a bit confusing.
Researchers have stated that the deformity may result from improper
cast technique applied to metatarsus adductus and/or clubfoot, but
there clearly are a number of idiopathic cases.

Although the deformity can result from improper casting
of metatarsus adductus with iatrogenic lateral subluxation of the
navicular and creation of valgus hindfoot (3),
its cause generally remains unknown. Most cases occur spontaneously
with a trapezoid-shaped medial cuneiform as seen in metatarsus adductus
(157,159), but the hallmark of the condition is medial deviation of the forefoot with lateral translation of the midfoot.

It is difficult to differentiate metatarsus adductus
from skewfoot in the infant, in whom no calcification of the navicular
or first cuneiform is present. However, clinically one may note a
significant valgus deformity in association with metatarsus adductus
and the ability to palpate the head of the talus in the longitudinal
arch. By direct observation (Fig. 30.21), a
deep concavity in the medial aspect of the foot, created by a step-off
between the head of the talus and the base of the first metatarsal, is
palpable. This is seen in association with adduction of the first ray
and valgus hindfoot. The deformity is generally flexible with

respect
to subtalar motion but somewhat rigid with respect to correction of the
forefoot. Callusing may be present under the head of the talus (Fig. 30.23) and at the base of the fifth metatarsal, as seen in severe metatarsus adductus (102,157,159). Tightness of the heel cord may cause symptoms of pain, as it often does in the flatfoot.

Because of lack of ossification of the bones of the
midfoot, radiographs taken at birth are difficult to interpret in
differentiating metatarsus adductus from skewfoot. It is, however,
noted that in metatarsus adductus, there is generally medial deviation
of the first ray, but that the proximal portion of the first metatarsal
is aligned with the head of the talus, whereas in the skewfoot (Fig. 30.24),
the first ray is translated relative to the long axis of the talus, and
may actually be parallel to it, and yet appear to be significantly
medially deviated. Attempts by Berg (140) to
radiographically differentiate metatarsus adductus from skewfoot in the
infant have been unrewarding because of poor interobserver and
intraobserver reliability (141).

Standing anteroposterior and lateral radiographs in the older child and adolescent are indicated in order to

determine the degree of deformity, both in the anteroposterior and lateral projections.

The natural history of skewfoot is unknown, but it seems
that many cases of mild skewfoot undergo spontaneous correction, as
happens with metatarsus adductus (3,4) and flexible flatfoot (1,46).
The long-term disability attributed to this deformity remains difficult
to estimate, but treatment is clearly required in some cases because of
pain and difficulty with wearing shoes at the end of the first decade
of life (102, 125, 126, 127, 136, 157, 158, 159, 160).

Treatment with cast correction for skewfoot in infancy
is difficult. In applying cast treatment to the forefoot deformity in
skewfoot, the risk is of increasing the valgus deformity in the
hindfoot and the lateral translation of the midfoot. Therefore, when
corrective casting is applied to skewfoot in early childhood, the foot
should be placed in a plantar-flexed position with slight varus to lock
the hindfoot and gentle pressure applied to the forefoot.
Overaggressive casting should not be undertaken (3,125, 126, 127, 138, 140). Dennis-Brown bars are not indicated in this condition.

Some older children and adolescents with skewfoot
deformity have pain and callusing under the head of the talus as well
as over the fifth metatarsal and the first metatarsal head medially (102, 157, 158, 159).
Tight heel cord is often associated with painful skewfoot, as is
present in a painful flatfoot. Stretching of the Achilles tendon is
indicated as part of conservative management. A soft orthosis to
support the talar head and the longitudinal arch and decrease the
deformity in the hindfoot may be of value. Use of a rigid orthosis in
this condition may cause increased pain and should be used cautiously.

Surgery is indicated if nonoperative treatment fails to
relieve pain and callosities. Operative management should be directed
at the specific deformity that appears to be associated with symptoms
in a given case; that is, if the lateral translation through the
midfoot and forefoot deformity is most prominent, treatment may include
closing-wedge osteotomy of the cuboid and lengthening of the first
cuneiform (Fig. 30.25), similar to metatarsus adductus. If, however, the deformity has a major component of hindfoot valgus (Fig. 30.26), it must be treated. Historical recommendations have included osteotomies at the base of the

metatarsals (136) and subtalar and triple arthrodesis of the hindfoot (147,148,160).
The use of arthrodesis in this condition should be avoided and attempts
at correction through osteotomy encouraged. Complications of triple
arthrodesis and subtalar arthrodesis are enumerated in the section on
flatfoot in this chapter. Mosca (157) proposed
correction of symptomatic skewfoot by combining individual osteotomies
of the forefoot and hindfoot to result in the correction of this foot
deformity (Fig. 30.26). The combination of a
calcaneal lengthening to correct hindfoot valgus as well as a first
cuneiform lengthening to correct forefoot deformity is warranted. This
is done according to the modified technique of Evans (102,161);
it is always associated with lengthening of the heel cord and generally
associated with medial reefing of the talonavicular joint. In Mosca’s
series (157), 9 of 10 patients with severe skewfoot achieved satisfactory clinical and radiographic corrections of skewfoot deformity.

The incidence of flatfoot deformity is unknown but clearly decreases with age, as described by Staheli (1,46). According to Harris (162),
flatfoot was present in 23% of 3619 adults. They classified them into
flexible, or hypermobile, flatfoot, which was generally asymptomatic
and accounted for at least two thirds of the flatfeet. In 25% of cases,
the flatfoot was associated with a tight heel cord and was much more
likely to be associated with symptoms (162,163). According to a study by Reimers et al. carried out in Danish schoolchildren (164), the proportion of feet with decreased longitudinal arch declined from 42% in the 3- to 5-year

age group to 6% in the teenagers. They found a strong relation between
short Achilles tendon and persistence of deformity in the teenagers.

Flexible flatfoot is a normal variation of foot
alignment in early childhood, with spontaneous resolution in the vast
majority of cases. Although muscle weakness has been proposed as a
possible etiology, Basmajian and Stecko (12)
demonstrated that little or no electromyographic activity of the
muscles of the foot and ankle is present when physiologic loads are
applied to a standing subject with the foot in plantigrade position.
They, therefore, concluded that the bone-ligament complex, and not
muscle contraction, determines the height of the longitudinal arch.
Mann and Inman (13) confirmed this theory. The
effects of extrinsic factors on the shape and development of the
longitudinal arch is suggested by studies from developing countries,
including those of Sim-Fook and Hodgson (5) and Rau and Joseph (6), finding a higher incidence of flatfoot in children wearing shoes than those who did not. Echarri and Forriol (165),
in applying Staheli’s index of arch development, found boys to have a
higher tendency for flatfoot than girls, and wearing of shoes to have
no influence on the height of the longitudinal arch or morphology of
the foot.

Recognizing the nearly universal presence of decreased
longitudinal arch in early infancy and its spontaneous resolution with
growth, one may be hard pressed to call this, in general, a pathologic
condition. However, in a number of cases, spontaneous resolution does
not occur and symptoms become quite significant. The difficulty is in
isolating the pathologic form of flatfoot deformity from the normal
developmental form. The general examination should include assessment
of ligamentous laxity as well as torsional and angular deformities. It
is noted that flatfoot deformity has a higher presence in association
with valgus deformities of the knees and generalized ligamentous
laxity. In the presence of external tibial torsion or external rotatory
deformity of the hip, the push-off in gait is compromised and the
deformity of flatfoot increased. In general, a flexible flatfoot will
revert to a normal position with the presence of a longitudinal arch in
a non-weight-bearing or sitting position. When rising on the toes, the
longitudinal arch will form and the hindfoot tip into the varus with
plantar flexion of the hindfoot and simultaneous development of a
longitudinal arch (Fig. 30.27).

Observation of the foot in a non–weight-bearing position
with the patient kneeling on a chair will often demonstrate the
hindfoot to be in neutral with an associated supination deformity of
the forefoot. In stance, the elevation of the great toe (in the Jack
toe-raise test) (Fig. 30.28) will produce an elevation in the longitudinal arch by using the windlass effect of the plantar fascia (159,166).
Dorsiflexion of the foot with knee extended and hindfoot slightly
inverted should be done to test for Achilles tendon tightness, as this
is the common pathologic state associated with painful flatfoot
deformity. Finally, the skin pattern on the plantar aspect of the foot
should be viewed, as callosities over the head of the talus are
associated with symptoms and greater severity of flatfoot deformity.
Sequential footprint measurements can be done in order to determine
severity of the foot deformity. Kanatli et al. (167) have shown an excellent correlation between footprint and radiographic analysis in flexible flatfeet in children. Lin (168)
showed that subjects with flatfoot deformity tended to perform physical
tasks poorly and walked more slowly than controls with healthy feet.
They also found that flatfoot deformity was associated with valgus
knees and generalized ligamentous laxity to some degree. They cautioned
against regarding flatfoot deformity as a static problem and encouraged
analysis of its effect on activity. Cowan et al. (169)
reported a study of prospective Army recruits, indicating that
low-arched individuals had no increase in the risk of injury, whereas
Kaufman et al. (170) reported an increased risk
of overuse injuries in patients with dynamic pes planus, particularly
with restricted ankle dorsiflexion.

In summary, in evaluating a patient with flatfoot
deformity, a complete physical examination must be done, testing muscle
strength of all lower extremity muscles and ruling out spinal pathology
by physical examination. Range of motion and alignment as well as
muscle strength and sensation should be evaluated in the lower
extremities. Tightness of the Achilles tendon and flexibility of the
foot deformity must be emphasized.

Radiographs of the flatfoot deformity are not generally
needed for routine evaluation. In severe cases, however, a series of
sequential lateral radiographs may be helpful in

determining
the course of the deformity. Radiographs, however, define only a static
position and cannot be used as an indication for treatment (46,171).

The lateral radiograph of the flatfoot reveals the Meary angle (172)
as measured between the long axis of the talus and the first metatarsal
and the calcaneal pitch, which are indicative of the severity of the
flatfoot deformity (Fig. 30.29). One may also
look for localized sag between the navicular and first cuneiform rather
than at the talonavicular joint, as this may have significant
implications for treatment. A tarsal coalition may also be evaluated
radiographically by standing anteroposterior, lateral, and oblique
radiographs. Brown et al. (173) found that the
C-sign on the lateral radiograph was more specific for flatfoot than
for subtalar coalition. Although some have felt that the C-sign (Fig. 30.30) was diagnostic of middle facet talocalcaneal coalition, it appears not to be so.

In the young child, a severe flexible flatfoot at times
must be differentiated from a vertical talus. In doing this, a
plantar-flexion lateral view of the foot is obtained in order to show
that the long axis of the first metatarsal becomes colinear with the
long axis of the talus on a lateral view (Fig. 30.30).

Flatfeet are ubiquitous in infants and spontaneously
resolve in most cases, as has been shown by Staheli and others. Shoeing
has no effect on the development of the longitudinal arch and may
actually be detrimental to it (165). There
appears to be a wide range of arch height at all ages, but in general,
there is consistent development of a healthy longitudinal arch during
childhood (Fig. 30.31). There are no long-term
prospective studies on the natural history of flatfoot deformity
related to symptoms. It does appear, however, that in select cases,
particularly in association with a tight heel cord, unresolved flatfoot
deformity may be associated with an increase in foot pain and stress
injuries in the lower extremities. Most authorities agree that flexible
flatfoot is an anatomic variant and not a disabling deformity (159,162,171).
Nevertheless, it may be associated with symptoms in its unresolved
state. Uncontrolled studies indicate some efficacy of orthotic devices
and shoe modifications in the development of the longitudinal arch in a
child’s foot (174). More recently, randomized
control studies reveal no benefit from shoe modifications and inserts
compared to normal development (175, 176, 177). In a study by Garcia-Rodriguez et al. (178),
the prevalence of flexible flatfoot was evaluated in school children
between the ages of 4 and 13 years. They found the prevalence of
flatfoot deformity to be 2.6%. However, 14.2% of the children were
receiving orthopaedic treatment, despite the diagnostic criteria for
flatfeet being satisfied in only 2.7% of the children. More
surprisingly, the children meeting the diagnostic criteria for flatfoot
deformity were only being treated in 28.1% of the cases. Overweight
children were found to be at greater risk of flatfoot deformity.
Caution against the rate and expense of overtreatment of a physiologic,
self-limiting deformity was raised.

Having said this, it should be noted that some children
with flexible flatfoot deformity may have activity-related pain. The
pain is usually diffuse or may be focal over the longitudinal arch. An
exam should be done to evaluate muscle tightness as well as the foot
deformity and flexibility of the flatfoot. If a tight heel cord is
found, a stretching

program should be begun. Mann and Inman (13)
found a higher incidence of intrinsic muscle activity in flatfoot
deformity, which may result in fatigue and pain during prolonged
standing. Over-the-counter or custom-molded shoe inserts have been
shown to relieve or diminish symptoms (179). Although arch supports do seem to provide relief in a number of cases, Miller et al. (180)
were unable to show any change in ground reaction forces relating to
the use of orthotic devices. The data were contrary to the current
hypothesis about the benefits of the use of an orthotic device.

Whether or not the ground reaction forces can be altered
by an orthotic device, it appears that symptoms can be significantly
decreased. With an external rotation position of the foot in push-off,
stresses over the midfoot are exacerbated. Use of an orthotic device
and/or supportive shoe may be of value in such cases. Surgery is rarely
indicated in flexible flatfoot deformity. However, in select cases,
despite attempts at conservative therapy with an exercise program and
proper arch support, surgery should be considered. Alignment of the
entire lower extremity emphasizing valgus alignment at the knee and
ankle and rotational alignment of the femur and tibia should be
considered. When surgery is to be considered, options include
soft-tissue reconstruction, osteotomy, arthroereisis, and arthrodesis.
Surgery for flexible flatfoot should be an infrequent procedure,
employed in cases of intolerable pain despite maximal conservative
management. Weight loss and correction of angular and rotational
malalignment of the legs, including ankle valgus, should be considered
preoperatively. In an occasional patient with a tight heel cord despite
a vigorous stretching program, judicious heel cord lengthening may have
a role in the management of flexible flatfoot, as an isolated
procedure. Beyond this, soft-tissue reconstruction plays no part in the
management of a persistently painful flexible flatfoot deformity.
Fusion, including localized midtarsal, subtalar, and triple
arthrodesis, has been recommended for the treatment of a flexible
flatfoot deformity over the past 70 years. Localized midtarsal
arthrodeses are all variants of a Hoke navicular cuneiform type fusion (181, 182, 183, 184, 185, 186, 187).
Each of these reconstruction arthrodeses may improve alignment of the
foot, but long-term results indicate poor outcomes in 49% to 70% of
cases. The results were classified as unsatisfactory based on
degenerative arthritis primarily involving the talonavicular joint,
pain, or recurrence of deformity. In response to unsatisfactory results
of limited arthrodeses, some have recommended triple arthrodesis as a
procedure of value to prevent midfoot and hindfoot arthritis. Long-term
results of triple arthrodeses indicate that this

procedure also carries a significant risk of long-term negative consequences based on adjacent degenerative arthritis and pain (188).
Therefore, present recommendations primarily include trying to
reconstruct the foot while maintaining all normal articulations.

Joint-sparing procedures based upon osteotomy appear to
be the option of choice for a flexible flatfoot at this time. Such
procedures improve alignment while maintaining mobility. There are two
osteotomies that hold promise for long-term relief of symptoms. Both
are calcaneal procedures, but one translates the calcaneal tuberosity
medially whereas the other lengthens the calcaneus with a positive
effect on hindfoot and forefoot alignment.

The calcaneal osteotomy that translates the tuberosity medially (189)
will not elevate the plantar-flexed talus, but will realign the
weight-bearing axis of the hindfoot. The isolated hindfoot osteotomy
may be combined with a closing wedge osteotomy of the medial cuneiform
and an opening wedge osteotomy of the cuboid to restore forefoot and
midfoot alignment, as described by Rathjen and Mubarak (190),
with good results. In cases in which the talus is not exceedingly
plantar-flexed and the navicular is not dorsolaterally translated, this
appears to be a valuable procedure, perhaps even the procedure of
choice. If there is a tight heel cord, one should consider a fascial
lengthening in association with this osteotomy.

The calcaneal lengthening osteotomy first described by Evans (161) and later popularized by Mosca (102, 157, 158, 159)
appears to offer the best opportunity to correct the flexible flatfoot
deformity, maintaining joint mobility while reconstructing bony
alignment. In this procedure, an opening-wedge osteotomy is performed
through the neck of the calcaneus between the anterior and middle facet
(Fig. 30.32), inserting a trapezoidal graft
(generally allograft) to maintain length. The effect of this osteotomy
in lengthening the calcaneus is correction of the eversion of the
subtalar joint. The osteotomy improves the valgus alignment of the
calcaneus, reduces the dorsolateral translation of the navicular into
proper alignment with the long axis of the talus, and improves the
talocalcaneal relation.

The alignment of the first metatarsal and long axis of
the talus as seen on the lateral view (Meary angle) is likewise
improved by this procedure (102, 161, 191, 192, 193).
Although the effects of this procedure on a flexible flatfoot are
primarily positive, it may supinate the forefoot elevating the first
ray. If this occurs, a plantar-flexion osteotomy through the first
cuneiform is mandatory in order to restore the tripod of the foot and
prevent an exacerbation of forefoot supination deformity (Fig. 30.32).
The effect of elevating the first ray is counteracted by an intact
peroneus longus that should be maintained while doing this lengthening
osteotomy. Heel cord lengthening and peroneus brevis lengthening are
always done as a part of this procedure.

Finally, “arthroereisis” should be discussed. In this
procedure, a block of material is placed in the subtalar joint in order
to eliminate motion in the flexible flatfoot (194,195).
The block may be sylastic or high-molecular-weight polyethylene, but in
either case there is a significant incidence of loosening,
displacement, and synovitis related to this procedure. Black et al. (196) and Verheyden et al. (197)
both recommended abandonment of this procedure because of a high rate
of negative outcomes. This is in contrast to the work of Grady (198)
who reported consistently excellent results in 234 children. Although
the author has no experience personally with this procedure, the use of
a nonbiologic implant in young children for what is generally a
self-limited condition seems illogical. Osteotomies seem to be of
benefit in the occasional patient to correct deformity and relieve
symptoms. Treating the asymptomatic flatfoot in children with a
surgical reconstructive procedure appears to be generally unwise and
unnecessary. In the face of neurologic conditions and pathologic
degrees of ligamentous laxity, however, some method of management of
the flexible flatfoot deformity may include such procedures, as
described by Smith and Millar (195).

A flexible flatfoot is a variant of the healthy foot that should be treated if it is painful or causing excessive shoe

wear. Conservative or surgical management of the commonly associated tight heel cord is mandatory for successful outcome.

Congenital vertical talus is exceedingly rare. Although it occurs as an isolated congenital abnormality in 50% of cases (200, 201, 202, 203), it is commonly associated with neuromuscular and genetic disorders including trisomy 13, 14, 15 (204) and trisomy 18 (205). Fifty percent of children have bilateral involvement, and there is no sex predilection (202).

Most cases are sporadic or associated with underlying
neuromuscular diseases. Case reports have indicated autosomal dominant
transmission with incomplete penetrance (203,206)
in some cases. Congenital vertical talus is associated with
myelomeningocele, sacral agenesis, diastematomyelia, and
arthrogryposis. In Sharrard and Grosfield’s series of patients with
myelomeningocele (207), 10% of patients had
vertical talus associated with spinal dysraphism. Given the frequency
with which this deformity is associated with neuromuscular disorders, a
thorough evaluation of the neuroaxis with MRI is indicated in patients
with vertical talus.

Congenital vertical talus has a rigid, convex plantar
surface, with a hindfoot resting in equinus and a hypoplastic,
laterally deviated forefoot (Fig. 30.33). Lloyd-Roberts and Spence (208)
described the appearance as “a prominence in the sole of the foot from
which the heel and forefoot rise in a gentle curve.” The Achilles
tendon is always contracted with a fixed equinovalgus position. The
head of the talus is palpable in the medial aspect of the midfoot. Upon
plantar-flexing the foot, a gap can be felt anterior and medially to
the medial malleolus as a space where the normal neck of the talus
should be, when the navicular plantar flexes over the head of the
talus. In contrast to a flexible flatfoot or a positional
calcaneovalgus foot, the talonavicular joint cannot be reduced by
manipulation. Some authors have differentiated a vertical talus from an
oblique talus (175,209).
An oblique talus is one in which there is dorsal subluxation of the
navicular, but some flexibility of the foot exists such that a rigid
dislocation of the navicular is not present; however, the foot is
significantly more rigid than a common flexible flatfoot. This term may
be confusing, but it is helpful if one considers it as describing a
foot that appears on physical examination to be nearly like a vertical
talus but that nearly reduces fully on a plantar-flexion view
radiograph. In such a foot, an oblique talus can be improved by
conservative management with casting and arch support, whereas surgery
is always required in a true congenital vertical talus.

Anteroposterior and lateral radiographs of the foot
should be taken in a neutral position, as in any pediatric foot
disorder. Standing radiographs are taken in a child able to stand;
however, in the infant, these radiographs are taken in a neutral
position. The diagnostic x-ray film of a vertical talus is a forced
plantar-flexion view (Fig. 30.30) in which
persistent malalignment of the long axis of the talus and the first
metatarsal are confirmed. Because the navicular and first cuneiform are
not ossified in infancy, the dislocation is implied by virtue of the
lack of colinear alignment of the first metatarsal with the long axis
of the talus. In a lateral x-ray film of a healthy, unstressed foot,
the first metatarsal is aligned with a long axis of the talus. The
position of the cuboid relative to the calcaneus should be determined,
as this is indicative of the severity of a vertical

talus. In the most severe form, there is a dorsal dislocation of the cuboid on the calcaneus.

Autopsy and surgical findings have confirmed consistent abnormalities in the musculature of the foot in vertical talus (210, 211, 212, 213).
Most have found contractures of the tibialis anterior, extensor
hallucis longus, extensor hallucis brevis, peroneus tertius, peroneus
longus, peroneus brevis, and the Achilles tendon. The peroneus longus
and peroneus brevis may be anteriorly subluxed over the lateral
malleolus, and the posterior tibial tendon may be subluxed anteriorly
over the medial malleolus. The head of the talus is generally
protruding below the posterior tibial tendon and the calcaneonavicular,
or spring ligament, is markedly attenuated. The calcaneus is severely
externally rotated and everted, with its posterolateral border in
proximity to the fibula. Sustentaculum talae and anterior facet of the
subtalar joint are exceedingly hypoplastic or absent in the most severe
cases. The dorsal capsule of the talonavicular joint is thickened and
contracted.

Untreated, a congenital vertical talus causes
significant disability, with poor push-off, difficult shoe fitting, and
a gait that is similar to one seen in a patient who has had a Symme
amputation. The forefoot becomes atrophic over time, with thick plantar
callosity forming over the head of the talus. No weight bearing occurs
either on the true heel pad over the calcaneus nor under the forefoot.
Eventually, push off becomes impossible.

Where cast treatment of clubfoot using the Ponseti
method has markedly decreased the role of surgical management in this
deformity, cast treatment of vertical talus has been rather ineffective
beyond providing stretching of the dorsolateral soft tissues. In
general, the foot is placed in a series of corrective casts in order to
stretch the dorsal structures, hoping that surgical treatment will be
rendered less complex. Casting is considered important by nearly all
who have studied this problem (202,203,212,214).
Following a series of corrective casts, an exercise program and,
perhaps, a bivalve cast or splint is used until the time of surgery.
Surgical options include one-stage or two-stage releases, talectomies,
naviculectomy, subtalar arthrodesis, and triple arthrodesis. Consensus
has lead to a single-stage procedure in most cases at this point.

Talectomy was recommended by Lamy in 1939 (199)
but was soon abandoned. It was destructive and resulted in unacceptable
outcome, not addressing the underlying pathology. It also left no
options for future reconstruction and has been thoroughly abandoned.
The primary choices for operative management of congenital vertical
talus in a child younger than 2 years are one-stage versus two-stage
reconstruction involving release of tight tendons and ligaments and
realignment of osseous structures. If a two-stage procedure is chosen,
the first stage consists of lengthening the contracted dorsolateral
tendons and release of the contracted dorsolateral joint capsule with
reduction of the midfoot on the hindfoot. The second stage consists of
a posterolateral release of the contracted Achilles tendon, peroneal
tendons, and posterior capsule. Ogata et al. (203) and Mazzocca et al. (215)
found increased complications in the two-stage release. Included in the
complications described by Ogata was avascular necrosis of the talus.

Most doctors now recommend a one-stage procedure (203, 214, 216, 217, 218, 219) and report results that are comparable to or better than those reported for the two-stage procedures (216,220,221).
Mazzocca and Romness compared the dorsal to the posterior approach for
one-stage correction of congenital vertical talus. The dorsal approach
was found to be associated with shorter operative time and better
clinical score with fewer complications than the posterior approach.
Several authors have reported the addition of a full or split transfer
of the tibialis anterior to the head or neck of the talus (214,216,217,222,223).
Although the transfer adds little time to the procedure, it would seem
that a dynamic stabilizer of the talus would be unlikely to be
particularly effective in maintaining talonavicular alignment, and that
this procedure, although brief, may complicate an already somewhat
difficult procedure. The author would not recommend the addition of the
anterior tibialis transfer. The peroneus longus, is a plantar flexor of
the first ray, is particularly strong, and complete transfer of the
anterior tibial tendon may lead to an unopposed plantar flexion force,
providing another reason not to alter the anterior tibial insertion.

It is not clear what the upper age limit for this
reconstructive approach is. There is disproportionate growth between
the medial and lateral borders of the foot in an unreduced vertical
talus and marked atrophy of forefoot and midfoot. The abnormality of
the middle and anterior facet of the subtalar joint become
progressively more severe in the unreduced state. Until the age of 2 or
3 years, there may be stimulus toward further growth of cartilage and
improvement of the talonavicular joint following reduction. Beyond
this, shortening of the medial column and lengthening of the lateral
column are approaches to management that may be required. Some authors
have recommended naviculectomy (224,225)
as a primary salvage procedure in congenital vertical talus. It may be
an effective procedure to shorten the medial column and allow
improvement of the position of the foot in the older child.
Posterolateral release has been combined with naviculectomy for full
deformity correction in a group of older children (Fig. 30.34). Coleman (106)
has recommended subtalar arthrodesis in children older than 3 years;
another alternative for this deformity is lengthening of the lateral
column, which may be done in association with peroneal lengthening in
select cases. Early diagnosis and treatment should eliminate the need
for surgical options in the older child. Nevertheless, occasional cases
requiring subtalar (222,223)
and triple arthrodesis have been reported. If triple arthrodesis is
indicated in this procedure, bone grafting will necessarily be used to
supplement

the
correction of the foot and restore proper alignment. The literature
clearly shows, however, that arthrodesis does result in a significant
rate of degenerative arthritis at the ankle and midtarsal joints in the
long term (188, 226, 227, 228, 229, 230, 231, 232). Napiontek (233)
reported overcorrection of the valgus foot in half the patients who
underwent peritalar reduction combined with subtalar arthrodesis.
Arthrodesis of the joints of the hindfoot, therefore, should be
reserved for salvage procedures in adolescents and those with recurrent
deformity or painful degenerative arthritis.

Positional calcaneovalgus foot is a foot deformity (Fig. 30.35)
in which the foot is hyperdorsiflexed, often with the dorsal surface of
the forefoot resting on the anterior surface of the lower leg. It is
thought to be primarily a positional deformity.

Because flatfoot deformity is very frequent in infancy, the incidence of calcaneovalgus foot depends on how liberally

the term is used. Wynne-Davies et al. (234) reported the incidence to be 1 per 1000 live births, whereas Wetzenstein (235)
noted a 30% to 50% incidence in the newborn, as well as a significant
correlation to flexible flatfoot in older children. It is more common
in girls and firstborn children.

The probable cause of this deformity is intrauterine
malpositioning, rather than a truly congenital deformation. Contracture
without congenital deformity or dislocation is the hallmark of this
condition.

Recognition of this generally benign condition,
differentiating it from pathologic states requiring orthopaedic
intervention, is mandatory. The calcaneovalgus foot deformity should be
differentiated from the following conditions:

Posteromedial bow of the tibia is a condition in which a
calcaneovalgus foot is always present but is associated with a bowed,
shortened tibia. The anterior compartment muscles appear to be somewhat
hypoplastic over the concavity of the bow at the distal tibia. The bow (Fig. 30.36C)
is benign and progressive straightening of the tibia occurs, but
leg-length discrepancy is always present. A vertical talus has a fixed
dislocation of the navicular on the talar head, as described in this
chapter. There is far less flexibility in a vertical talus than in a
calcaneovalgus foot deformity. A motor exam can differentiate the
paralytic calcaneovalgus foot deformity from the true positional
abnormality. If the foot is sufficiently flexible for the examiner to
be confident of the diagnosis of positional calcaneovalgus foot
deformity, no x-ray films are taken. In cases in which there is
confusion between a calcaneovalgus foot deformity and a true vertical
talus, a plantar-flexion lateral radiograph is indicated (Fig. 30.30).
Anteroposterior and lateral x-ray films are taken with which a
calcaneovalgus foot can be differentiated from a vertical talus. In
most cases, x-ray films are not required.

If the foot cannot be plantar-flexed below neutral,
casting is indicated. Exercises to stretch the tightened anterior
soft-tissue structures may be beneficial in speeding the resolution of
this positional deformity. Larson et al. (8)
found no difference between cases managed with exercise versus
observation of this deformity at follow-up of 3 to 11 years. Severity
of the initial deformity bears no relation to final outcome.
Wetzenstein (235) found correlation between a
calcaneovalgus foot and flexible flatfoot deformity in the long term.
Corrective casting is rarely judged to be of benefit if the foot cannot
be plantar-flexed below neutral, and particularly if there are
associated tight peroneal muscles and lateral deviation of the forefoot
with external tibial torsion.

Surgical treatment of calcaneovalgus foot is not required.

A tarsal coalition is a fibrous, cartilaginous, or bony connection between two or more bones of the hindfoot and midfoot.

The tarsal coalition has been associated with peroneal spastic flatfoot (236) since 1921 when Slomann (237)
linked the two conditions. A “peroneal spastic flatfoot” is a rigid
flatfoot deformity in which subtalar motion is exceedingly limited. The
rigid foot deformity is accompanied by spasm of the extensor digitorum
communis and the peroneal muscles in many cases. Harris and Beath (238)
further associated the findings of talocalcaneal coalition with
peroneal spastic flatfoot. Interestingly, tarsal coalition has also
been linked with an infrequently occurring tibialis posterior spastic
varus deformity (239,240).

Tarsal coalitions have been noted to occur with a number of other disorders, including fibular hemimelia (241), clubfoot (242), Apert syndrome (243)
and Nievegert-Pearlman syndrome. Such coalitions have also been seen in
lower-limb congenital abnormalities. Tarsal coalitions have been found
in monozygotic twins (244).

The overall incidence of tarsal coalitions was proposed
by Harris and Beath in 1948 to be 2%, on the basis of routine physical
examination of Canadian Army enlistees (238).
On the basis of a cadaveric study by Phitzner in 1896, the rate of
calcaneal navicular synostosis was found to be 2.9%, and if
talocalcaneal coalitions are included as well, its incidence might
reach 6% (245,246). More recently, a study by Lysack and Fenton (247)
documented a general prevalence of calcaneal navicular coalition of
5.6% in a radiographic study, which was significantly greater than
previously reported. The most common sites of tarsal coalition include
the middle facet of the talocalcaneal joint and the calcaneonavicular
coalition (238). Together these account for 90% of all coalitions (248). Tarsal coalitions are bilateral in 50% to 60% of cases. Clarke (249)
documented multiple coalitions in 6 of 30 patients on review
examination of CT scans, raising the question of what the true
percentage of feet with multiple coalitions may be. Also reported are
talonavicular coalitions, calcaneal cuboid coalitions, and navicular
cuneiform coalitions, although all of these are uncommon (248,250) (Fig. 30.37).

Wray and Herndon (251) have suggested autosomal dominant inheritance with variable penetrance based on a single family study. Leonard (252) has confirmed the autosomal dominant pattern of inheritance.

The tarsal coalition appears to be a relatively frequent
finding in the general population, with symptoms developing in late
childhood and adolescence. The possible etiologies of the painful
tarsal coalition associated with rigid flatfoot are (i) stress fracture
at a time when progressive ossification is occurring or (ii) limited
motion with altered hindfoot mobility causing increased stress across
involved joints. In either case, bone scan often shows increased uptake
in the area of the tarsal coalition. Children with syndromes such as
Apert syndrome have multiple coalitions and generally decreased
activity to a level where symptoms of the coalitions are limited.

Pain associated with valgus hindfoot deformity and
limited subtalar motion is the hallmark of tarsal coalition and
peroneal spastic flatfoot. Frequently, an insidious onset of aching
pain over the medial aspect of the foot in the talocalcaneal coalition,
and the sinus tarsi in the calcaneonavicular coalition, is present.
Pain is generally aggravated by activity and relieved by rest. Ankle
spraining associated with this is common. The flatfoot deformity
present is often severe and progressive in a child who has previously
had an intact longitudinal arch. Rigidity is because of restriction of
subtalar motion, so that the foot cannot be inverted as in the normal
physical examination. When the patient rises on tiptoes, the hindfoot
does not invert into its normal varus position (253) (Fig. 30.38).

The rigid flatfoot deformity, or peroneal spastic
flatfoot, can also be seen with juvenile rheumatoid arthritis, bone
lesions of the talus, calcaneus or midfoot, and trauma. Ruling out
arthritis and the other causes of rigid flatfoot deformity is mandatory.

A calcaneonavicular coalition is best seen on an oblique radiograph (Fig. 30.39A)
of the foot. The failure of segmentation of the tarsal bones in their
cartilaginous state results in a cartilaginous bridge, which
progressively ossifies forming a synostosis with age. On a standing
lateral view, an elongated process of the calcaneus to navicular can be
seen as the “anteater’s nose” (254) (Fig. 30.39B). Radiographic findings of talocalcaneal coalition include the C-sign (Fig. 30.40) as a line formed from the outline

of the talar dome extending around the inferior margin of the
sustentaculum tali. This has been thought to be a reliable indicator of
talocalcaneal coalition; however, Taniguchi et al. (255)
found the C-sign to have low sensitivity, meaning that the diagnosis of
tarsal coalition is not negated by the absence of a C-sign. Brown et
al. (173) found the C-sign to be specific for a
flatfoot deformity but neither sensitive nor specific for the diagnosis
of subtalar coalition. Liu et al. (256) found
that the absent middle facet was a more accurate sign in the diagnosis
of a subtalar coalition than either talar beaking or the C-sign (Fig. 30.40).

In all cases of suspected tarsal coalition, a standing
anterior and posterior radiograph of the ankle should be obtained. A
ball-and-socket ankle may be seen in cases of long-standing tarsal
coalition (257,258).

A talocalcaneal coalition can be seen on an axial or Harris view (238), but the best way to assess a coalition is with CT scan (Fig. 30.41) (259,260). More recently, Emery et al. (261)
showed that MRI was nearly as good as the “gold standard” CT imaging
for subtalar coalition. In cases where diagnoses such as bone lesions
of the hindfoot or midfoot are considered in the differential
diagnosis, an MRI is indicated rather than a CT scan. While MRI should
not be the first-line study, it can also identify possible fibrous
coalitions (262). Bone scan can also help in identifying the cause of foot pain with an atypical history or pain pattern (260).
Because a rigid flatfoot deformity can result from infection or other
inflammatory disease as well as bone lesions, a laboratory work-up
including a complete blood count (CBC) with differential, sedimentation
rate, C-reactive protein, ANA, and rheumatoid factor may be warranted.
Rheumatologic evaluation in difficult cases with adjacent joint space
narrowing may be helpful as well.

The cause of tarsal coalition remains unknown. The bones
of the foot are separate in infancy in 99% of individuals. Lack of
segmentation of the cartilaginous anlage occurs in some cases, and it
is possible that a fibrous connection between bones undergoes
metaplasia to cartilage (syndesmosis to synchondrosis) and finally to
synostosis (238,263,264).
A coalition alters the normal movement of the subtalar complex in gait.
When rotation and gliding are eliminated by the tarsal coalition,
increased force is concentrated across the talonavicular,
calcaneocuboid, and subtalar joints (265). The
altered motion may lead to degenerative changes in joints over time as
the stresses on cartilage may exceed tolerable limits. Another possible
etiology for symptoms is a stress fracture through the tarsal
coalition. This would account for the large number of individuals who
become symptomatic in adolescence when size and ossification
concentrate stress in the coalition. It is possible that this relates
to ligament sprain, peroneal muscle spasm, irritation of the sinus
tarsi, and irritation of adjacent joints in addition to the arthritis
and stress fracture previously mentioned (236). In general, however, the cause of the pain remains unknown (238,248).

According to Leonard (252), only
about 25% of individuals with tarsal coalitions become symptomatic. The
onset of pain coincides with the progression of the fusion of the
coalition. This generally occurs between 8 and 12 years of age for
calcaneonavicular coalitions and between 12 and 16 years of age for
talocalcaneal coalitions. As the feet become symptomatic, progressive
valgus deformity of the hindfoot, flattening of the longitudinal arch,
and restriction of subtalar motion occur (251, 253, 254, 257, 258, 259, 260, 262, 263, 266).

The goal of treatment is relief of pain and the
restoration of motion. The specific goal of reestablishment of the
longitudinal arch is less clear. Treatment is indicated only for
symptomatic tarsal coalitions (238,257,267). It is not clear that an asymptomatic tarsal coalition with mild restriction would benefit from a surgical excision.

In general, upon presentation with a painful foot and
diagnosis of tarsal coalition, attempts should be made to relieve
symptoms by nonoperative means including activity modification,
nonsteroidal antiinflammatory drugs, shoe inserts, and cast
immobilization in a below-knee walking cast. Pain may be eliminated
rapidly following cast application, and as many as 30% of patients
remain pain-free after cast removal following 6 weeks of immobilization
(263). However, Saxena et al. (268)
found that patients who underwent tarsal coalition excision reached
levels of activity beyond the level reached by a matched group of
patients forgoing surgical excision, questioning the wisdom of a
nonoperative approach in the marginally symptomatic patient.

Surgical options for patients with recurrent or
disabling symptoms include resection of the coalition, osteotomy, and
arthrodesis. This chapter will first consider these options applied to
the calcaneonavicular coalition first described by Badgley (269)
in 1927. In this procedure, the coalition is excised and an
interposition material inserted to prevent refusion between the
calcaneus and the navicular. The extensor digitorum brevis as an
interposition material improved outcome, preventing recurrence of the
fusion and providing relief from long-term pain (270, 271, 272).
The presence of a talar beak is not indicative of degenerative
arthrosis and is not by itself a contraindication to resection (273, 274, 275, 276).
Prior to resection of a calcaneonavicular coalition, one should ensure
that a second coalition is not present by analysis of a CT scan of the
hindfoot. The absence of degenerative changes in the talonavicular
joint and calcaneocuboid joint should be ensured. Significant
degenerative arthritis is a contraindication to surgical excision.
Cooperman et al. (277) demonstrated significant
variation in the extent of the fusion of the anterior aspect of the
calcaneus with the navicular. In his analysis of 30 specimens, the
anterior facet of the subtalar joint was totally spared in 8. The
anterior facet was partially replaced in 7 of 30 specimens and
completely replaced in 15. This variation in the anterior portion of
the subtalar joint, related to calcaneonavicular coalitions, may result
in some variation in outcome and certainly relates to the extent and
depth of the resection required to adequately treat this problem.
Failure to resolve symptoms with excision is often related to
inadequate resection at the time of the primary procedure with respect
to depth and breadth of this osseous fusion. A CT scan analysis of the
relation of the anterior facet of the subtalar joint to the calcaneal
navicular coalition will assist in surgical planning.

Indications for surgical resection of talocalcaneal
coalitions are a bit less clear and more complicated. The coalition is
located on the medial side, or tension side, of the valgus foot
deformity, and resection of a portion of the subtalar joint may lead to
further collapse into the valgus. It is stated that resection should
not be done if more than 50% of the subtalar joint surface is involved
with the coalition (273). Wilde et al. (276)
reported unsatisfactory results of resection in feet with a ratio of
the surface area of the coalition to the surface area of the posterior
facet greater than 50%, on the basis of CT scan evaluation. Luhmann and
Schoenecker (278) reported that there were good
postoperative results in feet with valgus deformities of less than 21
degrees but with posterior facet involvement of more than 50%. However,
valgus abnormality in excess of 21 degrees required postoperative
bracing and had compromised results. Many feet with poor outcomes have
narrow posterior facet or impingement of the lateral process of the
talus on the calcaneus. The resection of the talocalcaneal coalitions
therefore remains more controversial, and further study is required for
redefining the indications for resection.

Degenerative arthritis in either coalition is considered
a contraindication to resection, but this diagnosis may be difficult to
make. Talar beaking (Fig. 30.40) is not a sign of degenerative arthritis and not a contraindication to resection (273, 274, 275, 276). Successful resection and interposition in talocalcaneal coalition and calcaneonavicular coalitions have been

found to occur in up to 90% of cases at 10-year follow-up. Interposition materials in the talocalcaneal coalitions include fat (273,279) or a split portion of the flexor hallucis longus tendon (280).
Documented degenerative arthrosis with persistent and recurring pain
after coalition, particularly in adults, represents an indication for
arthrodesis (236). This may be either a triple arthrodesis or a subtalar arthrodesis (281),
depending on the joint and extent of involvement. Osteotomies to
improve realignment remain an alternative to arthrodesis, and the
medial closing wedge osteotomy of the calcaneus or sliding osteotomy to
treat severe valgus deformity should be considered (279,282).
Another surgical procedure that should be considered in feet with some
mobility is the calcaneal lengthening procedure described by Evans; it
can be used following resection of an osseous coalition of the middle
facet in select cases. Although long-term studies are not documented
for this procedure, recognized problems with long-term outcome of
triple arthrodesis are well recognized and alternatives should be
sought (188,226,227,232).

Juvenile hallus valgus, or bunion deformity, is
characterized by lateral deviation of the great toe with prominence of
the first metatarsal head medially. The apex of the deformity is at the
first metartarsal phalangeal joint and it is often associated with a
flatfoot, more commonly in women.

The true incidence of hallux valgus deformity is
unknown. It is more common in girls than in boys, with girls accounting
for more than 80% of cases. Usually there is a strong family history,
with most patients inheriting the deformity from their mothers (283, 284, 285, 286, 287). Coughlin and Roger (288)
found a positive family history of bunion deformity in nearly three
fourths of patients reported in his series. No inheritance was present
in 70% of cases (288,289).
The Mendellian inherence pattern of juvenile hallux valgus has been
proposed to be X-linked dominant or autosomal dominant with very
variable penetrance (290,292).
As in many cases where complex inheritance patterns are present, it has
been described as a polygeneic or multifactorial inheritance pattern as
well. The cause of hallux valgus deformity is both extrinsic and
intrinsic. Studies of hallux valgus in children who wear shoes compared
to those who do not show an increased risk with footwear (152,292).
However, most evidence leads to the conclusion that juvenile hallux
valgus is a deformity negatively influenced by constricting footwear
but usually secondary to a structural abnormality of the foot (288,289,293).

Flatfoot deformity has been determined to be a risk
factor for the development of hallux valgus, as well as its recurrence
following surgical correction, by a number of authors (284,294,295).
However, others feel that flatfoot deformity does not predispose to the
occurrence of juvenile hallux valgus deformity. Coughlin and Roger (288), Kilmartin and Wallace (296), and Canale et al. (285)
found no correlation between pes planus and the rate of success with
surgical correction. The relation between the length of the first
metatarsal and the development of hallux valgus has been studied as
well. Excessively long first metatarsal (284,288,297) and a short metatarsal (298) have been implicated in the incidence and severity of juvenile hallux valgus. However, Coughlin and Roger (288)
have shown that the lengths of the first and second metatarsal in
children with adolescent bunions are similar to those in a healthy
population.

There is an association between metatarsus primus varus,
which is defined as an intermetatarsal angle between the first and
second rays of greater than 10 degrees, and juvenile hallux valgus. The
cause of the varus deformity of the first metatarsal may lie in an
abnormal cuneiform–first-metatarsal articulation. The distal articular
surface of the first cuneiform is normally transverse; however, an
oblique orientation of this joint may predispose to a varus deformity
of the first metatarsal (295). The second angle
that is important in quantifying the hallux valgus deformity is the
hallux valgus angle defined by Hardy and Clapham (289). This angle is measured by the intersections of the longitudinal axis of the proximal phalanx and the first metatarsal (Fig. 30.42). The normal hallux valgus angle is less than 16 degrees (299).

The final important skeletal abnormality to consider in
the quantification of the juvenile hallux valgus deformity is the
lateral deviation of the articular surface of the first metatarsal. The
distal metatarsal articular angle (DMAA) quantifies this alignment (Fig. 30.43) (288,290,300,301). The higher the DMAA, the greater the valgus deformity of the distal metatarsal articulation. Coughlin and Roger (288)
reported a 48% incidence of juveniles with hallux valgus having an
increased DMAA and a congruous first metatarsal phalangeal joint,
significantly greater than in adults (300). He noted that the DMAA was significantly higher in patients with positive family histories and early onset of hallux valgus.

As the deformity of hallux valgus progresses, the flexor
tendons and sesamoids sublux laterally; the adductor of the great toe
inserting on the proximal phalanx increases the deformity, and finally,
once the hallux valgus deformity is present, the abductor hallucis with
its plantar insertion on the proximal phalanx has no ability to abduct
the great toe.

Most adolescents with hallux valgus are asymptomatic,
and the mild pressure present over the metatarsal head medially can be
relieved by proper shoe fitting. When pain is present, it is generally
directly over the medial prominence of the first metatarsal head, as
well as overlapping of the second toe over the laterally deviated great
toe. Intraarticular pain and arthritis are rare in juvenile hallux
valgus. Restriction of motion at the metatarsal phalangeal joint is
also rare.

In general, juvenile hallux valgus is present
bilaterally in women with positive family history. In cases of
unilateral deformity in a woman with a negative family history, be
aware of other causes of muscle imbalance that might lead to a bunion
deformity. Examples of these are central nervous system lesions such as
cerebral palsy, spinal dysraphism, or other spinal cord abnormality,
and peripheral nerve lesions.

On physical examination, look for associated flatfoot
deformity, particularly with tight Achilles tendon. Also look for other
causes of pain surrounding the metatarsal phalangeal joint such as
arthritis, inflammation, or lesions of local soft tissue or bone.

Standing anteroposterior and lateral radiographs of the
foot are necessary in order to evaluate hallux valgus. First, the
overall alignment of the foot should be documented on standing views,
measuring calcaneal pitch and the first metatarsal to long axis of the
talus (Meary angle) on the lateral view. With respect to the bunion
deformity, the hallux valgus angle, the intermetatarsal angle and the
DMAA should be measured. Look for metatarsal phalangeal joint congruity
and relative lengths of the first and second metatarsal. An abnormality
of the proximal phalanx with trapezoidal shape or an abnormal
interphalangeal joint may be present with hallux valgus. Cadaver study
by Vittetoe et al. showed that the intraobserver reliability of DMAA
measurement was high, and interobserver reliability was poor (302).

The natural history of juvenile hallux valgus is not known. Piggott (300)
believed that congruous joints with juvenile hallux valgus were stable
and less likely to progress than those with subluxations. Congruous,
laterally deviated metatarsal phalangeal articulation is much more
common in children than in adults. A congruous first metatarsal
phalangeal joint is found in 9% of adults (300) but in 47% of juvenile patients with bunions (288).

Patients seeking treatment of hallux valgus either
complain of deformity, or pain, or both. There is an assumption on the
part of many patients and parents that prompt treatment of

the
deformity will resolve and cure this problem. This approach—early
correction of the deformity to alleviate the potential for long-term
difficulty—has no role in management of hallux valgus deformity. In
pediatric orthopaedics, we often try to correct deformities early, in
order to keep them from becoming significant problems in the future;
not so for bunions. This “hands off” approach is counterintuitive, both
to patients and their parents. Pain is the primary indication for
treatment of hallux valgus deformity rather than malalignment, because
of the significant recurrence rate. Perhaps there is a role for early
conservative management with night splinting to prevent progressive
bunion deformity. This opinion is based on the work of Groiso (286),
who reported a 50% success rate in night splinting, using an orthoplast
precut splint, holding the great toe in an abducted position at night.
His series included 56 children with 2- to 6-year follow-up. Half the
children showed significant improvements in the metatarsal phalangeal
angle and the intermetatarsal angle. A contrary view was expressed by
Kilmartin et al. (303), who found that hallux
valgus deformity increased more in patients who used splints than those
who did not. The pillar of conservative management is finding shoes
that fit appropriately and have a widened toe box. The upper portion of
the shoe should be soft, and an arch support can be used to decrease
the tendency for pronation of the foot.

Surgery is indicated when pain cannot be managed with
alteration of footwear, and a significant change in activity is
required in a child. The age of the patient at the time of surgery is a
significant consideration. Poor results with high complication rates
have been reported consistently in 30% to 60% of young children who
have had hallux valgus surgery (273, 304, 305, 306, 307). The results have been attributed to a number of factors, including further epiphyseal growth causing progressive deformity (283),
growth arrest of the proximal first metatarsal and proximal phalanx,
and return of the proximal phalanx to its position of congruent
articulation. The return of the great toe to a position of congruent
articulation with increasing bunion deformity is a particularly
significant problem in patients with an elevated DMAA. Coughlin and
Roger (288) and others (307)
have, however, performed successful surgical reconstructions with low
complication rates in adolescents with open growth plates. The authors
stress that if possible, surgery should be delayed until the end of
growth.

All surgical procedures have the following components:
distal soft tissue realignment (McBride procedure), metatarsal
osteotomy (either proximal or distal), and attention to the DMAA.

Also, the excision of the medial eminence in hallux
valgus should not be aggressive, because a large protuberant medial
eminence is rarely seen in children.

Soft tissue realignment should not be performed in
isolation because recurrent deformity will uniformly result. In the
face of a subluxed metatarsal phalangeal joint, soft tissue realignment
may be valuable. In addressing soft tissue abnormalities, medial soft
tissue realignment generally involves a VY reconstruction of the medial
capsule, as well as a lateral release of the adductor tendon. With soft
tissue realignment as an isolated procedure without osteotomy, there is
a 50% to 75% recurrence rate in adolescents (284,288). Hallux varus has also been reported following this procedure (308,309). Therefore, soft tissue repair alone has been abandoned.

Osteotomies are central to the treatment of juvenile
hallux valgus deformity. The osteotomies may be the distal first
metatarsal as used in a chevron or Mitchell type osteotomy, the
proximal first metatarsal, or the medial cuneiform. In order to make
the decision of where to do the procedure, radiologic evaluation is
required. For the congruous metatarsal phalangeal joint, a distal
osteotomy may be used to correct the DMAA, whereas a proximal
metatarsal osteotomy or medial cuneiform osteotomy is used to correct
the metatarsus primus varus (290,310) (Fig. 30.44).
In some cases, an additional osteotomy at the base of the proximal
phalanx is required. If the intermetatarsal angle is less than 15
degrees, a simple distal osteotomy, either Mitchell or chevron, can be
used. Standard uniplanar chevron or Mitchell osteotomies do not correct
the DMAA. Translating the metatarsal head laterally and correcting the
angular deformity can be done with effort, using internal fixation with
K-wires to maintain angular correction of the distal fragment and
correction of the DMAA (283, 285, 290, 304,306, 311, 312, 313, 314).
Minimal lateral soft tissue release should be combined with distal
metatarsal osteotomy because of the risk of avascular necrosis (315).

Results of the Mitchell osteotomy vary among series. Ball and Sullivan (304) reported a recurrent valgus deformity in 11 of 17 patients, or 61%. Canale et al. (285)
reported 31% of patients in their series with a fair or poor outcome;
the less than satisfactory results related primarily to poor position
of the displaced distal fragment, resulting in recurrent deformity, or
plantar angulation resulting in transfer lesions to the second
metatarsal head. Such problems can be decreased with appropriate use of
internal fixation.

A number of very positive series, using the Mitchell
osteotomy, have been reported, with positive outcomes ranging from 81%
to 95% (66,283,311,316).
Positive outcome from this osteotomy related to preserving the length
of the first metatarsal and never dorsiflexing the metatarsal head
while stabilizing the osteotomy with a screw or K-wire.

Another distal metatarsal osteotomy that is highly
effective in managing a bunion deformity with an intermetatarsal angle
of less than 15 degrees is the chevron osteotomy. The chevron (314)
osteotomy is a transverse osteotomy through the distal portion of the
metatarsal with a chevron shape. The apex of the chevron osteotomy is
at the midportion of the metatarsal head, and the angular limbs
transverse the cortex of the metatarsal, proximal to the capsular
insertion (317). Good results from this osteotomy have been reported by Zimmer et al. (314)
in 85% of adolescents despite a recurrence rate of 20%. The
intrinsically stable osteotomy avoids the problem of metatarsal
shortening. The DMAA can be corrected by angulating the distal
articular surface.

In cases where the intermetatarsal angle (Fig. 30.44) exceeds 15 degrees, correction of the primary varus deformity of the first ray is necessary (288,290,305).
If the medial cuneiform distal surface is angulated, an opening wedge
osteotomy through the cuneiform can be done. Peterson and Newman (310)
described a two-level osteotomy for adolescent bunions doing a closing
distal medially based osteotomy with an opening proximal-based
metatarsal osteotomy in which the length of the metatarsal is
preserved, the varus deformity corrected, and the DMAA properly aligned.

There is no role for excisional type arthroplasties in
the management of bunion deformity in children. Occasionally, an Akin
osteotomy, which is a medial closing wedge of the proximal phalanx (318),
may be used to improve the alignment of a toe in which the metatarsal
alignment is proper and the DMAA appears satisfactory. Hallux valgus,
therefore, should be corrected where the deformity lies. In the
presence of cerebral palsy, bunion deformities are quite common, both
dorsal bunions and hallux valgus. Because of exceedingly high
recurrence rates, fusion of the first metatarsal phalangeal joint is
the procedure of choice (319, 320, 321).

In summary, treatment of adolescent bunions may involve
conservative treatment with night splinting and observation.
Appropriate footwear should always be encouraged. Surgical treatment
should be delayed until the end of growth if possible, and the
procedure chosen should treat the deformity present in a given case.
There is no indication for isolated soft tissue repair in the juvenile
bunion deformity.

Congenital overriding fifth toe is an abnormality
present at birth, in which the fifth toe is adducted, dorsiflexed, and
medially deviated, generally lying over the metatarsal phalangeal joint
of the fourth toe (Fig. 30.45).

The true incidence of this deformity is unknown, because
mild forms of the disorder are present in an asymptomatic state, below
the threshold for treatment. There is no sex predilection. In 20% to
30% of cases, bilateral involvement is present (322, 323, 324).

The cause of a dorsal dislocation or overriding fifth toe is unknown but there is a familial predilection for this deformity (323).

In this state, the fifth toe is dorsiflexed and overlies
to some degree the fourth toe and fourth metatarsal phalangeal joint.
The interphalangeal joints are normal. The skin tends to be contracted
a bit dorsally and medially, but there is no stress or abnormality on
the skin.

Although difficult to image, x-ray films should be taken
to determine whether or not the metatarsal phalangeal joint is subluxed
or dislocated prior to surgical treatment.

There is a contracture of the dorsomedial capsule of the
fifth metatarsal phalangeal joint, but the toe is not a clawed toe.
Flexion deformity of the interphalangeal joint does not occur.
Shortening of the extensor tendons of the fifth toe is generally
present and must relate to the dorsal position of the toe. The entire
toe is translated proximally and medially.

Actual incidence of pain from this condition is
uncertain, but it has been stated that approximately half of affected
individuals will experience symptoms from this deformity, generally
from shoe wear (323).

Although there is no proven efficacy to stretching and
taping of the toe, it may be of benefit to patients in whom the
deformity is somewhat mild. Education about the reasonably good
prognosis of the untreated state is worth pursuing; however, in the
case of a committed family with a patient having mild deformity, taping
may be of value. In taping, a loop of standard adhesive tape is brought
around the toe and it provides a plantar tether to the toe.

Surgery is indicated for roughly 50% of adolescents and adults who experience pain with shoe fitting (323). The toe in its medially deviated and dorsiflexed state will

overlie the metatarsal phalangeal joint just at the point where the shoe fold will lie.

Many surgical procedures have been proposed to correct
this, including partial or complete excision of the proximal phalanx
and syndactylization to the fourth toe (325). Only fair results have been reported with this approach, and secondary deformities persist in many cases (325). Amputation is only a salvage procedure. The Butler procedure (322,324) originally reported by Cockin (323)
is a very successful approach for the management of this condition. A
racket-handle incision is made to release the contracted soft tissues
dorsally and medially, mobilize the neurovascular bundles, and free the
toe for translation. The toe is then translated plantarlaterally.
Although there is a risk of neurovascular compromise, this is very
infrequent. Plantar skin reconstruction with a VY advancement resolves
the problem of the soft tissue tether. If the toe spontaneously
subluxes, further release of the dorsal capsule and dorsal soft tissues
should be done, and the toe can be pinned in position across the
metatarsal phalangeal joint at the time of the soft-tissue
reconstruction.

A “curly toe” is a congenital deformity in which one or
more of the toes are flexed and have a varus deformity, generally with
lateral rotation through the interphalangeal joints, causing the toe to
curl and lie under the adjacent or more medial toe (Fig. 30.46).

Curly toe is a very common deformity, although the true
incidence is not known. It is very frequently bilateral and symmetric,
with high familial incidence (326,327).

The cause is unknown; the condition is often associated with a tight toe flexor, but not always.

The third and fourth toes are most frequently involved.
The distal phalanx or the distal and middle phalanges are pulled under
the adjacent medial toe with flexion, varus, and external rotation of
the distal and proximal phalanges. The nail plate of the affected toe
often faces laterally. If the deformity is magnified when dorsiflexion
of the foot and the MP joint tighten the flexor tendon of the toe, the
primary pathologic structure causing the deformity is probably the toe
flexor. This can be confirmed by showing that the deformity can be
decreased by plantar-flexing the foot and ankle, thereby relaxing the
toe flexor.

Radiographs are neither needed nor helpful in the young child.

The flexor digitorum longus and the flexor digitorum brevis tendons may be affected and contracted in curly toe deformity (328).
Joint capsules are generally not affected. Occasionally this deformity
results from a trapezoidal deformity of the bone, and the curly toe
deformity is unrelated to flexor tendon but secondary to structural
abnormality of the toe.

Curly toes are generally asymptomatic in young children. Many improve in shape spontaneously (327,328).
They may become symptomatic in older children, adolescents, or adults,
because of exaggerated pressure on the skin and nails of malaligned
toes. The nail of the underlying toe often cuts the plantar surface of
the overlying toe, causing symptoms.

Stretching and taping have no proven efficacy in the treatment of curly toes (327)
but may work in mild cases. The family may be educated that, in
general, symptoms are rare and long-term disability is unlikely. Some
patients do experience continued pain and problems from curly toe
deformity. If associated with a tight toe flexor, stretching exercises
might be of benefit. Prior to embarking on surgical treatment, an
attempt at correction of a tight tendon may be of value. Surgery is
indicated if there are callosities and cutting of one toe into the
other, secondary to this deformity. Another indication is an
unacceptable problem with nail deformity.

Tenotomy of the flexor tendon has been successful in 95% to 100% of cases (326,328).
A double-blind, randomized prospective study comparing simple tenotomy
of the long toe flexor to Girdlestone-Taylor transfer showed no
difference in outcome (329). In this study, 19
patients with bilateral deformity involving the third and fourth toes
were operated on, using a flexor tenotomy release on one side and a
flexor tenotomy with flexon transfer procedure on

the
other. At 4-year follow-up, it appeared that there was no difference
between the two procedures and that simple tenotomy of the flexor
tendon is sufficient treatment for the symptomatic curly toe.

“Accessory navicular” is a term applied to a plantar
medial enlargement of the tarsal navicular beyond its normal size. A
separate bone, either in the posterior tibial tendon (such as sesamoid
bone) or with a true articulation with the navicular, is within the
breadth of this diagnosis. Other terms that have been used to describe
the separate ossicle are the os tibiale externum, the navicular
secundum, or the prehallux (Fig. 30.47).

The accessory tarsal navicular is the most common
accessory bone in the foot, occurring in between 4% and 14% of the
population (162,330,331). It is frequently bilateral and occurs more commonly in women. Geist (331) recognized a higher incidence of accessory naviculars in young patients evaluated radiologically than in cadaver studies.

McKusick (332) believed that accessory navicular was inherited as an autosomal dominant trait. Geist (332)
suggested that three possible situations accounted for the accessory
navicular: (i) bone within the substance of the posterior tibial tendon
as a sesamoid bone, (ii) bone with a true articulation (synovial-joint)
with the navicular and (iii) a synchondrosis.

Accessory navicular tends to produce symptoms in
adolescents. There is a firm prominence distal to the talar head on the
plantar medial aspect of the midfoot. This may be associated with
flexible flatfoot (333, 334, 335, 336).
The accessory navicular, however, is a primary abnormality in the
navicular and posterior tibial tendon relationship and is not related
to flexible flatfoot (337). The prominence of
the navicular is associated with point tenderness; it can be
differentiated from the prominence of the talar head in a flatfoot
deformity by inverting and everting through the subtalar joint with a
thumb over the bony prominence.

Individuals suspected of having an accessory navicular
should have standing anteroposterior and lateral radiographs in order
to define the abnormality of the navicular. Bilateral films may be
indicated, as there is a high incidence of symmetrical abnormalities.

Accessory navicular may be a pathologic finding leading
to foot pain, or perhaps an associated abnormality not related to the
clinical disorder with which the patient presents for evaluation.
Therefore, careful examination differentiating other causes of foot
pain is mandatory. Patients with accessory navicular may present with
complex pain patterns requiring very careful examination prior to
treatment (338). They may even have a peroneal spastic flat foot.

In general, standing anteroposterior and lateral
radiographs of the foot are diagnostic of accessory navicular. There
are three types of accessory navicular (339) (Fig. 30.47). In type I accessory navicular, which is rarely symptomatic, a small sesamoid bone is located in the posterior

tibialis tendon. Type II accessory navicular is the most frequently
symptomatic type, which is a bullet-shaped ossicle joined to the
tuberosity of the navicular by a synchondrosis. Type III is a large
horn-shaped navicular, which most likely is the result of fusion of a
type II accessory navicular with the progress of age.

There is proliferating vascular and mesenchymal tissue,
with growth of fibrocartilage and evidence of bone turnover, in the
tissue between the ossicle and the main body of the navicular in the
painful type II accessory navicular (339).
These histologic findings are consistent with healing microfracture or
a chronic stress fracture, substantiating the opinion that repetitive
stress leads to this injury. There is a possibility of finding
inflammatory cells at some stage in the healing process, but the
primary pathology is associated with healing microfracture rather than
chronic inflammation.

Accessory naviculars are for the most part asymptomatic.
If symptoms do occur, a period of protection from stress and injury
generally returns the patient to the asymptomatic state (335).

Nonsurgical treatment of accessory navicular often
relieves symptoms. Pain is related to a state similar to that seen in
stress fracture or Osgood-Schlatter disease. The decrease in direct
pressure over the accessory navicular, as well as decreasing stress
from the posterior tibial tendon insertion, may result in relief of
symptoms. This can be done with an orthotic device or arch support or a
soft shoe and a pad placed around the navicular to decrease direct
pressure over it. Finally, the patient can be given a short leg cast to
decrease symptoms by decreasing stress from the posterior tibial tendon
insertion.

If pain is persistent after a period of observation and
immobilization, surgery is indicated. There are two possible operations
for treating the accessory navicular. The first is simple excision of
the ossicle and the expanded portion of the navicular through a
tendon-splitting approach (331, 332, 333, 344).
In this procedure, the skin incision should be made dorsal to the
prominence of the accessory navicular. The bone is removed to a point
where the medial foot has no bony prominence over the navicular,
between the head of the talus and the first cuneiform. This generally
requires removing the accessory navicular as well as a prominent
portion of the navicular. Symptoms are relieved in 90% of cases by this
procedure.

The second possible procedure is a Kidner procedure (333,334),
in which the posterior tibial tendon is advanced along the medial side
of the foot with the hope of supporting the longitudinal arch. In this
procedure, the ossicle and the prominent medial aspect of the navicular
are excised, just as in the simple excision procedure, but the
posterior tibial tendon is advanced. There appears to be no benefit to
the advancement of the posterior tibial tendon relative to the simple
excision procedure (12,340).

Congenital hallux varus is the medial deviation of the
great toe on the first metatarsal, present at birth. It occurs as an
isolated deformity but is often associated with other malformations of
the foot, particularly, short first metatarsal; bracket epiphysis of
the first metatarsal, both pre- and postaxial polydactyly; and a
fibrous band that acts as a tether along the medial side of the great
toe, extending to the base of the first metatarsal (Fig. 30.48) (345,346).

This is a rare condition with unknown incidence. Inheritance pattern and other characteristics are not reported.

The cause of this deformity is not known, but it is
associated with a first metatarsal that is short and rounded, leading
to a very abnormal metatarsal-phalangeal articulation and medial
deviation of the great toe with an enlarged web space between the first
and second digit. Healthy growth of the first metatarsal is generally
compromised, and the medial tether leads to recurrence.

The great toe may be adducted as much as 90 degrees and cannot be aligned by passive manipulation (Fig. 30.48).
This should be differentiated from the medial deviation of the great
toe, which is a flexible and very common deformity seen in association
with metatarsus adductus. The hallmarks of the congenital deformity are
the fibrous band along the medial side of the foot, the widened web
space between the first and second digit, and the abnormality of the
first metatarsal. Duplication of the great toe with preaxial
polydactyly is quite common, and this may be associated with a complex
syndactyly, as seen in Apert syndrome (243).

A standing anteroposterior and lateral radiograph should
be done to assess the varus alignment of the great toe. The deformity
of the first metatarsal can be partially delineated on initial x-ray
films. However, the longitudinal physeal bracket, which may not be
easily seen on initial films, is suggested by a D-shape to the
metatarsal, with no cortical differentiation along the convex medial
border of the epiphysis (347) (Fig. 30.49A).

A possible explanation for a single varus toe is that
the origin of the deformity is related to preaxial polydactyly or
duplication of the great toe. The more medial extra digit degenerates
into a fibrous band, rather than fully forming a digit with a
corresponding metatarsal. The rudimentary medial structure then forms a
fibrous band that acts as a bowstring, pulling the hallux into a varus
position (348) (Fig. 30.48B).

In the foot with a longitudinal bracket epiphysis, a
growth disorder leading to progressive relative shortening of the first
metatarsal occurs, unless addressed.

In the absence of treatment, shoe fitting becomes increasingly difficult or impossible (346).
Mild forms of hallux varus with a flexible deformity generally resolve
spontaneously, but that condition should be differentiated from
congenital hallux varus.

There is no role for conservative management of this
deformity. Surgical management is indicated with the specific
procedures to be done depending upon the anatomy in the individual
case. The issues to be considered are correction of polydactyly if
present; correction of the soft tissue tether on the medial side of the
foot and the enlarged web space between the great and second toe;
correction of metatarsal-phalangeal joint incongruity; and correction
of metatarsal or bracket epiphyseal deformity (349).

Soft tissue release and resection procedures have been described by McElvenny (345) and Farmer (350) when the metatarsal is normal. Mills and Menelaus (348) found that soft tissue realignment procedures were often unsatisfactory

because of shortness of the first metatarsal and growth disorder. In
the soft tissue reconstruction of this deformity, which is part of any
surgical procedure, lengthening the medial tether is mandatory. This
requires resection of the fibrous band as well as Z-plasties in the
skin to increase the length along the medial side of the foot. The
abductor hallucis must be released and the tether on the capsule must
also be released.

The skin of the web space between the first and second
toe is resected and the medial reefing of the capsule done if possible.
The incongruity of the metatarsal phalangeal joint may need to be dealt
with by using a K-wire to hold the great toe in position while
remodeling occurs following surgical reconstruction.

The second issue to be dealt with is the bony deformity of the metatarsal. Mubarak et al. (347)
demonstrated that resection and interposition grafting of a
longitudinal epiphyseal bracket is an effective technique to treat
growth disorders resulting from this epiphyseal deformity (Fig. 30.49 B and C).
When the longitudinal portion of the bracket is excised, interposition
material with fat or methylmethacrylate can be used, as with any
physeal bridge resection. This procedure is always combined with a soft
tissue reconstruction and resection of duplication of the digits. An
opening wedge osteotomy may be combined in some cases in which the
extra bone from the toe can be used as part of an opening wedge
osteotomy.

Late onset of degenerative arthrosis of the first metatarsal phalangeal joint can be managed by arthrodesis (346).
Alternative treatments for pain with residual shortening and deformity
include metatarsal lengthening and amputation. Amputation is a
particularly valuable alternative in the management of severe
congenital hallux varus deformity in Apert syndrome (243).

Polydactyly refers to a congenital abnormality in which
extra digits are present, with or without duplication of the
corresponding metatarsal. Preaxial polydactyly refers to the medial
side of the foot and postaxial polydactyly to the lateral side of the
foot. Simple syndactyly refers to a failure of separation of otherwise
healthy digits with skin connection only. Complex syndactyly refers to
fusion of bone in the digit or metatarsals in adjacent rays.

The incidence of polydactyly is 0.3 to 1.3 per 1000 live births in whites and 3.6 to 13.9 per 1000 live births in blacks (351,352). Fifty percent of cases are bilateral, and of the bilateral cases 62% are symmetric (353). Of the patients with polydactyly of the feet, 34% have hand involvement (353). Polydactyly may be inherited as an autosomal dominant trait with variable penetrance (354) but is more likely to occur as an isolated trait.

The cause of polydactyly is unknown. Presumably, there
is failure of differentiation in the apical ectodermal ridge (AER)
during the first trimester of pregnancy, leading to polydactyly and
polysyndactyly (353). Experimentally, polydactyly can be produced by radiation, cytotoxins, and folic acid deprivation.

Temtami and McKusick (354)
classified polydactyly as preaxial if the great toe is duplicated and
postaxial if the duplication involved the lateral side of the foot. The
term “central” may be applied to a duplication of the second, third, or
fourth toe, if this can be differentiated. Phelps and Grogan (353)
in a review of 194 supernumerary toes showed 79% to be postaxial,
whereas 15% were preaxial and 6% central. Considerable variation exists
and more than one type may be present in a single foot (Fig. 30.50).
Syndactyly may accompany the extra digit, and toenails may be fused or
separated. Central and postaxial polydactyly tend to be well aligned,
whereas the preaxial polydactyly may be associated with congenital
hallux varus, short first metatarsal, and longitudinal bracket
epiphysis (347,349).

A morphologic classification of the abnormalities of metatarsals and phalanges in the foot was proposed by Venn-Watson (355) (Fig. 30.51).
The classification system is based primarily on metatarsal
abnormalities. The metatarsals are present on radiographic views at
birth, but generally radiographic evaluation is delayed in order to
allow full ossification of the phalanges for surgical planning.

Untreated polydactyly may cause problems with shoe fitting and angular deformity of the toe.

The management of a duplicated digit is determined by the family to some degree. A postaxial or central polydactyly

with proper alignment of the digit may remain in place unless the foot
is significantly widened. However, a malaligned toe, particularly
preaxial polydactyly, requires surgical treatment. Lateral or postaxial
polydactyly is generally treated with excision, with the assumption
that this is a relatively simple procedure in infancy and the wide foot
will become a problem with shoe fitting in the future.

In general, the most malaligned toe is resected, but effort is made to always remove the border digit of the foot (353,356).
Division of a synchondrosis at the base of the proximal phalanx is
quite safe, and growth arrest is highly unlikely. Likewise, an enlarged
metatarsal head may be reduced in size by performing a transphyseal
longitudinal osteotomy (353). In a case with a
duplicated metatarsal or Y-shaped metatarsal, the corresponding
metatarsal abnormality should always be removed at the time of
resection of the extra digit.

In cases of polysyndactyly, the most malaligned
phalanges and associated toenail generally are removed through a
racket-type incision (353,356).
The nail fold should be recreated to prevent problems with chronic
ingrown toenail. As polydactyly is often associated with syndactyly, a
decision must be made about reconstruction of both the extra digit and
the syndactyly. In general, the skin bridge between the toes is left in
place and the lateral border digit removed, if surgery is chosen (356).
Postaxial polydactyly generally results in satisfactory outcome with
excellent results. Preaxial polydactyly, on the other hand, is more
likely to result in residual varus deformity, short metatarsal, and
unsatisfactory outcome. Attention to the longitudinal epiphyseal
bracket (347) may result in improved length of
the first ray and should be considered in cases when this deformity is
present with preaxial polydactyly.

Syndactyly of the toes is a fusion of adjacent digits
involving soft tissue (simple syndactyly), or soft tissue and bone
(complex syndactyly). The most common fused digits are the second and
third, which may be either complete or incomplete (Fig. 30.52).

Syndactyly is a common, often inherited trait that is frequently bilateral.

Pathologenesis is unknown, but presumably in early fetal development there is a failure of separation of cells in the AER.

Webbing of the toes is rarely associated with the
angular abnormality of the digit that causes problems. Occasionally,
differential length of the toes may result in a flexion deformity of
the longer toe and a callus over the proximal interphalangeal (PIP)
joint. Rarely, this may become a problem with pain.

Radiographs should be done if deformity is present and
surgical management is planned, in order to differentiate simple from
complex syndactyly.

In general, syndactyly of adjacent digits is
asymptomatic throughout life, and surgical treatment and adaptive shoe
wear are generally not needed.

Surgical treatment in general is not warranted for
syndactyly as comfort and function are not impaired. Given presently
available footwear, which often includes a strap between the first and
second toes, a case can be made for surgical management in select
cases. Caution must be exercised, as the surgical scars may be less
cosmetically pleasing than the condition itself and lead to angular
deviation of digits from contracture, where satisfactory alignment was
present in the preoperative state. Unlike fingers, discriminatory
function of individual digits is not required in the toes, and toe
syndactyly is rarely surgically managed. If toe deformity is occurring
because of differential growth, a case for surgical reconstruction may
be made.

The cause of this condition is unknown and there is no clear inheritance pattern (358). Turra et al. (359) hypothesized a nerve trunk disease as the cause of macrodactyly, but this theory has not been confirmed (358).

An enlarged digit is present at birth and characterized
as “macrodactyly.” Features of Klippel-Trenaunay-Webber and
neurofibromatosis should be checked for. In neurofibromatosis, café au
lait spots are frequently apparent. In Proteus syndrome, a cerebriform
skin pattern on the plantar surface of the foot as well as asymmetries
of growth and nevi are present. Surprisingly, in
Klippel-Trenaunay-Webber, a syndrome of venous lymphatic malformation,
ipsilateral macrodactyly is frequently present with a vascular
component, and contralateral macrodactyly is present as a fibro-fatty
disorder. Fifty percent of patients with foot involvement in
macrodactyly have a dorsally angled digit with weak toe flexors (360).

Standing anteroposterior and lateral radiographs of the
foot are useful for monitoring growth rates of digits and for surgical
planning. MRI (361) is of value in macrodactyly
in order to differentiate cases of vascular malformation in association
with macrodactyly from true fibro-fatty disorders or lymphedema.

There is enlargement of both soft tissue and bony
tissues in the foot. In general, there is an overabundance of
fibro-fatty tissue, often in a neural distribution. The cause of the
overgrowth remains unknown.

Macrodactyly may be progressive, with proportional
growth throughout the life of the child. It may, however, be
progressive with disproportionate overgrowth compared to healthy digits
(362). The type with progressive overgrowth is more likely (358). It may be disabling, with respect to shoe fitting and the possibility of wearing commercially available shoes.

In cases of macrodactyly, the treatment of a child needs
to be individualized and must be recognized to be a long-term
commitment to that child and family. Treatment involves several options
including soft tissue debulking, amputation, and epiphyseodesis. In
general, ray resection of the toe and corresponding metatarsal are the
most satisfactory procedures to use in dealing with this condition of
the foot (363). Toe amputation alone has not
been cosmetically satisfactory, nor has it resulted in significant
improvement of the foot deformity. In mild cases, epiphyseodesis of the
proximal phalanx (364) and of the distal metatarsal, as well as surgical debulking, may be of some value (358, 359, 364, 365, 366, 367).
Ray resection combined with debulking of soft tissue has the best
outcome and lowest risk of recurrent deformity, achieving the goal of
shoe fitting with commercially available footwear in some cases (358,359,367) (Fig. 30.54).
In selecting the timing for epiphyseodesis of the foot, the author
generally uses an x-ray film of the affected child’s parent’s foot in
order to predict the approximate rate of growth of the healthy foot and
therefore timing of epiphyseodesis. Growth charts for the size of the
foot were developed by Green (Fig. 30.1);
however, it is preferable to use the size of the parent’s foot and the
size of the contralateral foot for timing of epiphyseodesis. A
successful ray resection should remove the entire metatarsal. If the
proximal metatarsal is left in place, the space between the first and
second metatarsal remains wide and an unsatisfactory outcome will
result.

One should expect multiple debulking procedures to be
necessary in the management of macrodactyly, and the parents should
understand this at the outset of the procedure. The author has found
that debulking procedures in the presence of lymphedema are less
successful than in cases of fibro-fatty type macrodactyly or vascular
malformation.

A cleft foot is characterized by a central deficiency involving soft tissue and bone (368). The term “lobster claw foot” used by Cruveilhier (368) in 1829 is no longer appropriate as a description of this clinical condition.

The cleft foot is a rare condition with an overall occurrence rate of 1 per 90,000 live births (369). The most common form of this condition is inherited as an autosomal dominant condition with variable penetrance (369, 370, 371).
The much less common form of this condition has an incidence of
approximately 1 per 150,000 live births, in which there is a
spontaneous mutation and no evidence of a familial condition.
Approximately 10% of cleft feet are of this pattern (372). Boys are affected more frequently than girls.

This condition results from an abnormality in tissue differentiation at the AER (373);
such a defect might be caused by genetic or toxic influence, leading to
an error in differentiation. Such irregularities may lead to
polydactyly or syndactyly or the much more rare central defect of cleft
foot. Watson and Bonde (374) proposed that a
specific region in the AER localized to the second or third ray, which
is the typical area for deficiency in a cleft foot. They further
proposed that the extent of damage to the AER would relate to both the
width and depth of the cleft defect of the foot.

The range of cleft foot is from a simple deepening of an
interdigital space to a central ray deficiency or even a monodactylous
foot (375). Associated abnormalities include
cleft hand, cleft lip and palate, deafness, urinary tract
abnormalities, triphalangeal thumbs, and tibial hemimelia.

The classification of the cleft foot into six types (Fig. 30.55) was done by Blauth and Borisch (375).
The classification system is based on the extent of bony deficiency of
the central rays, culminating in a foot with a nearly absent medial ray.

Beyond this classification system are two forms of cleft
foot: the monodactylous foot with a single ray, and a tibial diastasis
with central ray deficiency of the foot. Other variations include cross
bones and synostosis (Fig. 30.56). Radiographs
of the foot should be taken at presentation in order to classify the
deformity appropriately. Other diagnostic studies include renal
ultrasonography as indicated to rule out renal abnormalities as they
are frequently associated with cleft foot.

Synostosis and significant abnormalities of the tarsal bones may coexist with cleft foot and should be considered (375).
Often a hallux valgus results from the pull of a conjoined flexor and
extensor, resulting in an abductor as a component of this deformity.

Many patients with cleft foot function well and can wear
regular shoes without pain or compromise of function. For such
individuals, no surgical treatment may be required. However, in many
cases of cleft feet there is a marked increase in width (Fig. 30.57),
which prevents normal shoe fitting. Painful callosities develop over
the medial and lateral metatarsal heads. A severe hallux valgus is
frequently present, secondary to a conjoined flexor extensor tendon.

Treatment of the cleft foot should focus on the goal of
the ability to wear a standard shoe without pain and with good
function. A secondary goal is reconstructing the foot to a socially
acceptable appearance. Surgical repair is recommended for feet in which
a significant improvement can be

made
in the shape of the foot, facilitating shoe wear and improving
function. In recommending surgical repair, it should be remembered that
most cleft feet can function quite well without repair. Bony
prominences, medially and laterally, cause pain because of direct
pressure from footwear, rather than pain from walking. Wood et al. (376)
recommended surgical therapy for closure of a cleft foot, in which soft
tissue is reconstructed by a series of rectangular flaps. The flaps are
approximated and metatarsal osteotomies performed. Their reported
experience was of 42 operations in 15 affected feet that were felt to
warrant surgical repair, and their recommended age of patients was
between 6 and 12 months. The author has resorted to reconstruction,
creating a web space using a Barsky flap from one of the border digits
to define the depth of the new web space, and closure of the cleft
using a zigzag skin repair. In addition to the skin repair, the
underlying tendon reconstruction and metatarsal osteotomies are
important in this reconstruction (Fig. 30.58).
There frequently is a conjoined flexor and extensor tendon to the great
toe functioning as an adductor and causing a severe hallux valgus. The
recognition of this with centralization of both the extensor and flexor
tendon and division of the conjoined tendon as an adductor is
important. Metatarsal osteotomies and midtarsal osteotomies are used to
narrow the foot and reconstruct the cleft, in addition to soft tissue
repair. Complex plastic surgical procedures to create the appearance of
toes have been described, but they do not produce functional benefit (377).

The cavus foot is one with an elevated longitudinal
arch. The high arch may be secondary to plantar-flexion deformity of
the forefoot (forefoot equinus) or dorsiflexion of the calcaneus (378).
The hindfoot is generally in varus, but may be laterally oriented or in
valgus at times. The forefoot is generally pronated with a
plantar-flexed first ray.

A cavus foot results from muscle imbalance between
opposing extrinsic or intrinsic muscle groups. A very high proportion,
greater than two thirds, of patients with a cavus foot have an
underlying neurologic disorder (379). The
number of cases termed “idiopathic” cavus foot continues to decrease as
diagnostic methods improve. The diagnosis of hereditary sensory motor
neuropathy (HSMN), which includes the types I and II
Charcot-Marie-Tooth (CMT) (380), is the most
common neurologic disorder resulting in this deformity. On physical
examination, in addition to considering the array of systemic diseases
resulting in cavus foot, one should also explore the structural
abnormality and muscle imbalance that leads to this disorder. Forefoot
plantar flexion involving primarily the first ray is the most common
structural problem leading to a cavus foot. In this state, the first
ray plantar flexion compromises the normal tripod structure of the
foot, shifting weight bearing laterally and driving the hindfoot into
varus. This may result from weak anterior tibial muscle relative to
peroneus longus muscle (7), overpull of the extensor hallucis longus compensating for a weak anterior tibial muscle (68), or intrinsic muscle contracture of the foot with weakness (2).
With time, the plantar fascia contracts and the varus hindfoot
deformity becomes fixed. The second major group of cavus feet are those
with a dorsiflexion deformity of the calcaneus; this generally is the
result of weakness in the gastrocsoleus complex (Fig. 30.59) and a

compensatory push-off augmented by toe flexors. Any abnormality in the
neuromuscular axis may affect muscle balance in the foot, contributing
to a cavus deformity. Bilateral involvement suggests a systemic
condition, whereas unilateral cavus deformities suggest a more
localized differential diagnosis (Table 30.2).

The cavus foot occurs at the frequency of the underlying
neurologic condition. That is, the frequency of CMT or Freidrich ataxia
in a given population will define the frequency of the cavus foot that
is secondary to these deformities.

Presenting symptoms of a patient with cavus foot are
generally related to either instability or pain. Instability may be
secondary to muscle weakness, sensory loss, or deformity (381).
The pain is generally related to prominence of the metatarsal heads,
callosities over the toes, or malalignment increasing the stresses of
weight bearing. Muscle contraction is not required to maintain erect
posture with a healthy, balanced foot. With excessive plantar flexion
of the first ray, the normal tripod (first metatarsal, fifth
metatarsal, and calcaneus) is lost, leading to an abnormal force
distribution. In the malaligned state, not only are stresses increased
across joints and pressures increased on bony prominences, but also
muscle strength is required to maintain posture. The combination of
these leads to pain, fatigue, and instability.

Clinical presentation varies from patient to patient. A
frequently reported symptom is a recurrent spraining of the ankle with
a feeling of giving out. Ligament injuries as well as the malalignment
lead to pain. Blistering and calluses result over bony prominences.
This is particularly true over the dorsal aspects of the
interphalangeal (IP) and PIP joints, as well as the plantar aspect
under the metatarsal head and lateral border of the fifth metatarsal.
Muscle weakness related to the underlying condition leads to giving out
with loss of the dynamic stabilizers of the ankle, particularly the
peroneal muscles. Finally, sensory loss, particularly position and
vibratory, disrupts the normal feedback loop that provides dynamic
stabilization of the ankle.

As a cavus foot is generally secondary to an underlying
neuromuscular abnormality, symptoms at presentation may reflect the
underlying condition. A history of change in foot shape or change in
foot size is important. Family history is critical; if possible,
examination of other members of the family, rather than simply asking
for history of underlying medical conditions, can often be revealing
because a subtle cavus foot may be present. Further medical, birth, and
developmental histories, as well as a review of systems, are mandatory
in searching for underlying causes of cavus foot.

The clinical examination should be done, observing a patient’s stance (Fig. 30.60)
and gait first. In a sitting position, the foot can appear to have a
high arch but be completely flat in stance. In the swing phase of gait,
the foot dorsiflexion may be the result of isolated extensor hallicus
longus (EHL) contraction, rather than a coordinated activity of
anterior tibial as well as EHL and toe extensors. Look at foot position
at heel strike, as weight may immediately shift to the lateral border
of the foot. Does heel strike occur or is forefoot equinus preventing
heel strike and there is no contact of the calcaneus with the ground?
Are there any compensatory features of gait present such as knee
hyperextension or Trendelenburg compensation at the hip? The spine
should be evaluated for evidence of scoliosis, cutaneous defects over
the spine typical in diastomatomyelia, or fatty deposits seen in
lipomeningoceles.

A detailed muscle examination including strength testing
and reflexes must be done in all cases. Sensory examination should
include light touch, pain, and vibratory sense. Stocking and glove
sensory loss may be reflective of underlying peripheral neuropathy.
Despite varied patterns of muscle imbalance, the cavus deformity with a
plantar-flexed first ray is rather constant (382, 383, 384).

The foot should be observed for flexibility with
localization of the deformity to the forefoot or hindfoot. A tight
plantar fascia is palpable as a subcutaneous band along the
longitudinal arch with stretching of the forefoot. The

hindfoot is evaluated using the Coleman block test (Fig. 30.15) (385).
In this test, a 1-inch block is placed under the lateral border of the
foot allowing the first ray to plantar-flex without driving the
hindfoot into varus. In the common case where the plantar-flexed first
ray is the primary problem in cavus foot, the hindfoot will shift
beyond neutral into a position of slight valgus, as stance is assumed (Fig. 30.61).
The hindfoot should also be examined with the patient in prone position
or kneeling in order to evaluate the isolated position of the hindfoot
and eliminate forefoot deformity. The degree of hindfoot flexibility is
vital for surgical planning.

Hindfoot equinus is very uncommon in the cavus foot,
whereas varus and calcaneus deformity are seen quite frequently.
Flexibility or rigidity must be determined, as treatment implications
are critical. With the flexible state, tendon-balancing procedures are
effective, whereas rigidity of deformity requires osteotomy and at
times arthrodesis. Toe deformity with MP hyperextension and PIP flexion
are important to identify and treat. With the foot dorsiflexed, the toe
flexion deformity is accentuated by tightening the flexor hallucis
longus and the flexor digitorum communis. With plantar flexion, the
extrinsic toe flexors are relaxed and the deformity of the PIP and MP
joints can be determined. Tender callosities over joints must be
documented.

Standing anteroposterior and lateral radiographs of the
foot are obtained in all cases as part of the initial evaluation. Even
in mild cases, knowing the radiologic appearance of the foot
establishes a baseline on which future evaluation of progression can be
judged. The standing lateral film is most important for evaluation. The
long axis of the talus should be collinear with the long axis of the
first metatarsal. Deviation from this with the dorsal apex is seen in
cavus foot deformity. This has been termed the Meary angle.
The angle between the first metatarsal and the long axis of the
calcaneus is the Hibb angle, and this is a gauge of the elevation of
the longitudinal arch. In the normal state it is greater than 150
degrees but it steadily decreases as cavus foot worsens (Fig. 30.62).
Finally, the calcaneal pitch is the angle between the calcaneus and the
horizontal and is a measure of hindfoot sagittal plane deformity.
Cock-up toe deformity and MP dorsal subluxations should be observed as
well. In the anteroposterior view, there is normally an angle of
approximately 30 degrees between the talus and calcaneus. With
increased varus deformity of the hindfoot, this angle lessens and the
talus and calcaneus become increasingly parallel. Further diagnostic
studies generally involve anteroposterior and lateral views of the
spine and sacrum, looking for underlying deformity that may relate to
etiology. Beyond this, MRI of the neuroaxis may be indicated, as well
as complete neurologic evaluation, electromyography (EMG), and nerve
conduction velocities in order to complete the search for etiology.

Although some have said that there is little role for
nonoperative treatment of the cavus foot, the author believes this
should be reconsidered. This is a frequently progressive

deformity
that must be monitored. Tightness in the heel cord should be managed
with a stretching program, and weakness in dorsiflexion and peroneals
may be countered by an exercise program to improve strength and a
lightweight brace or angle foot orthoses (AFO) to prevent recurrent
spraining or injury. Although a specific program to stretch the
longitudinal arch or plantar fascia may not be effective in altering
the natural history of this condition, preventing equinus deformity is
valuable, and attempts to improve or maintain muscle balance should be
pursued. Plantar callosities are often bothersome and painful to
patients. These symptoms may be ameliorated with an appropriate arch
support with metatarsal pad. A properly made orthotic may significantly
improve symptoms and delay or prevent the need for surgical
reconstruction (386).
Management rather than cure of the cavus foot is the concept to
remember. As cavus deformity is usually secondary to neuromuscular
disease, continued problems and further treatment should be anticipated
(188,226,227,378,386,387).

Surgical correction is dependent upon the definition of
the deformity present, determined by physical exam and radiographic
evaluation. The elevation of the longitudinal arch (Hibb angle)
universally requires a plantar fascia release. A plantar-flexed first
ray that is flexible may be balanced by tendon transfer, whereas a
rigid deformity requires an osteotomy in order to correct the
plantar-flexion deformity. The hindfoot may have fixed varus deformity
(Coleman block test) (385) and require an
osteotomy for correction, or it may be flexible and assume normal
posture simply with correction of the first ray or forefoot deformity.
On the other hand, the entire forefoot may be involved in such a way
that midfoot osteotomy is required in order to achieve correction.
Finally, toe deformity must be corrected. No single prescription for
surgical correction of cavus foot can be found, but a group of
operations applied to specific deformities for individual patients
allow satisfactory management of the cavus foot deformity.

Plantar fascia release is a standard in all cavus foot procedures (383,386).
In this procedure, the plantar fascia and the origin of the abductor
hallucis is released. The neurovascular bundle is identified under the
fascia of the abductor hallucis and followed distally into the plantar
aspect of the foot. In doing this, the plantar fascia can be safely
released. Open rather than percutaneous release should be done, as
tight plantar structures need to be released in addition to simply
dividing the superficial fascia. Steindler (388)
described a procedure in which the intrinsic muscles of the foot were
released extraperiosteally with correction of the deformity. Release of
the calcaneonavicular ligament may facilitate correction of a severe
elevation of the longitudinal arch when combined with corrective
casting. Plantar midfoot and hindfoot release when combined with
corrective casting has been shown to be of some value by Paulos,
Coleman, and Samuelson (383) as well as by Sherman and Westin, who (389) noted that in up to 85% of patients, significant correction of residual cavus deformity in clubfoot could be treated

with extensive plantar release and corrective casting. Corrective
casting has no role in a calcaneal cavus foot with increased calcaneal
pitch. Further stretching of the hindfoot and weakening of the
gastrocsoleus will result without significant correction of the
longitudinal arch. In poliomyelitis, or conditions in which the
deformity is secondary to weak gastrocsoleus and a pistol-grip
calcaneus deformity is present, there is no role for corrective casting.

The concept of muscle-balancing procedures affecting first ray deformity should be considered next. Figure 30.63
shows the effect of two pairs of opposing muscle forces on the first
ray. These opposing force couples are the anterior tibial muscle versus
the peroneus longus, and the extensor hallucis longus versus the flexor
hallicus longus and intrinsics. In the face of a weak anterior tibial
muscle, the peroneus longus plantar flexes the first ray. The EHL
overpulls with dorsiflexion of the great toe, plantar flexing the
metatarsal head as the toe flexor produces an IP flexion deformity as
well. Two muscle-balancing procedures providing benefit to the first
ray in a cavus foot are the peroneus longus to brevis transfer and the
Jones transfer, or EHL, to first metatarsal head, accompanied by IP
fusion. In the peroneus longus to brevis transfer, the two tendons are
sewn together just distal to the fibula, and the distal portion of the
peroneus longus tendon is divided. In the EHL transfer (Jones
procedure), the tendon is divided at the MP joint and the proximal
tendon is placed through the metatarsal. The distal stump of the EHL
tendon is transferred to the extensor brevis, and an IP fusion of the
great toe is done to prevent subsequent flexion deformity of the great
toe. Tynan and Klenerman (390) showed that this
transfer was highly effective in treating clawing of the hallux and
plantar-flexion deformity of the first ray in 90% of cases; it was,
however, unreliable in curing pain under the first metatarsal head,
helping only in 43% of patients at follow-up. Breusch et al. (391)
showed that the overall rate of patient satisfaction was 86%, but that
the problems of catching of the big toe when walking barefoot and
transfer lesion to the second metatarsal head occurred. They also noted
that transfer of the peroneus longus to peroneus brevis was a
significant risk factor for elevation of the first metatarsal. In cases
with significant peroneal weakness it should not routinely be used as
in many cases of cavus foot, the lesser toes are involved with clawing,
with plantar flexion of the lesser metatarsal heads as well, resulting
in pain and deformity. The balancing procedures for the lesser toes
involve transfer of the extensors to the metatarsal heads with IP
fusion, with or without flexor tenotomy. Another alternative in a case
with a weak anterior tibial tendon is transfer of the entire group of
extensor tendons to the cuneiforms in an effort to augment weak
dorsiflexion, as described by Cole (392). Mulier, Dereymaeker, and Fabry (393)
found an association between metatarsalgia and long, clawed toes. With
transfer of the extensor digitorum longus tendons to the metatarsal
necks, symptoms were relieved in 25 of 33 affected feet. Although
symptoms were improved in the remainder, residual deformity remained.
Fabry believed that the transfer of the long extensor tendons to their
respective metatarsal necks with IP joint fusion was an excellent
procedure for patients with metatarsalgia and pes cavus deformity.

A rigid deformity of the first ray requires corrective
osteotomy prior to or in association with tendon transfer. Following
plantar fascia release, one must make a decision about the
correctibility of the first ray deformity or flexibility of the foot.
If one has any question about the persistence of a plantar-flexion
first ray deformity, osteotomy is required. The osteotomy may be a
plantar opening wedge of the first cuneiform (Fig. 30.62);
this is a stable osteotomy in which bone graft can be used to maintain
the corrected position of the osteotomy. Cuneiform osteotomy avoids the
risk of growth arrest in the proximal first metatarsal in a growing
child. Frequently, the center of rotation in a cavus foot is in the
midfoot or cuneiform, making this osteotomy preferable to metatarsal
procedures. For more severe deformities of the midfoot, a first
cuneiform osteotomy will not be sufficient. Midfoot osteotomies, as
described by Cole (392), Japas (394), Jahss (395), and Wilcox and Weiner (396)
may be used to correct the forefoot and midfoot component of the cavus
deformity. These procedures sacrifice midfoot joints and mobility but
correct forefoot deformity. The talonavicular joint and calcaneal
cuboid joints are preserved in midfoot

osteotomies.
The amount of correction achievable with midfoot osteotomy is dependent
upon the shortening of the foot and the size of the wedge that is
removed. They are accompanied by plantar release. Maximal correction
for midfoot osteotomies is in the range of 20 to 25 degrees. Excessive
correction through the midfoot may lead to a rocker-bottom deformity of
the foot and should be avoided. In select cases, metatarsal osteotomies
may be of value in correction of forefoot deformity. This is
particularly true if residual medial deviation of the forefoot remains
after soft tissue release. A greenstick dorsal closing wedge of the
metatarsals has been described by Swanson et al. (397) and Gould (398). Watanabe (399) found 84% good or excellent results in individuals treated in this manner.

With respect to the hindfoot, ignored so far in this
discussion of cavus foot, one must ensure that varus deformity is
corrected. Rarely is calcaneal pitch decreased with equinus coming
primarily from the hindfoot in cavus foot deformity. In reviewing a
large number of patients with CMT, Atkas and Sussman (400)
found the hindfoot always to be in slight dorsiflexion, with equinus
deformity resulting primarily from forefoot and midfoot alteration in
anatomy. Rigid hindfoot varus is best addressed by a modified Dwyer
osteotomy. In this osteotomy, closing lateral wedge of the calcaneus is
combined with a slide or translation of the calcaneal tuberosity to
achieve improved correction. Sammarco and Taylor (401)
reported on a series of combined calcaneus and metatarsal osteotomies
for cavus foot in 15 patients with excellent results, both clinically
and radiologically. Symptoms of metatarsalgia as well as instability
were corrected by this procedure. A pain-free, plantigrade foot was
achieved without sacrificing motion as would be required with
arthrodesis. Occasionally, deformity is sufficiently severe and rigid
that there is no alternative to triple arthrodesis. Although it was
generally thought that a triple arthrodesis would provide long-term
plantigrade foot, Schwend and Drennan (402)
have shown that progressive deterioration over time, secondary to
muscle imbalance, occurs even after triple arthrodesis. Balancing
procedures, therefore, are recommended in association with this
hindfoot fusion. The two types of triple arthrodeses that are indicated
in severe deformities are the Beak triple arthrodesis as described by
Siffert et al. (115) and the Lambrinudi triple arthrodesis as modified by Hall and Calvert (116).
In these operations, the wedges of bone removed allow correction to a
plantigrade foot. In the Beak triple arthrodesis, a portion of the
talus and navicular is removed to achieve satisfactory alignment of the
foot. In the Lambrinudi procedure, a wedge of talus is removed with a
cut perpendicular to the long axis of the tibia, allowing correction of
equinus deformity through bony cuts of the triple arthrodesis.
Similarly, varus deformity is corrected in this manner and internal
fixation achieved with staples or screws.

Complications of triple arthrodesis include pseudarthrosis, primarily of the talonavicular joint. Adelaar et al. (188) described a long-term follow-up with a 61% success rate, compared to Schwend and Drennan’s series (402),
which had a very low long-term success rate after triple arthrodesis.
Patients in Adelaar’s group were primarily affected with poliomyelitis,
whereas patients in Schwend and Drennan’s group had neuromuscular
disease with progressive muscle weakness and therefore progressive
imbalance. Triple arthrodesis should be reserved for patients where
other procedures will not provide sufficient correction of deformity to
achieve a plantigrade foot. In equivocal cases, patients should be
aware of the need to attempt correction through osteotomies and soft
tissue releases, withholding arthrodesis for severe, recurrent, or
residual deformities in which no alternative is present. Finally,
Ilizarov management has been used in a number of cases of severe foot
deformity with reasonable improvement. A combination of distraction
osteotomy and joint correction is used in order to achieve satisfactory
alignment. This may represent a valuable alternative to triple
arthrodesis, but more data is required in this area. Kucukkaya et al. (403)
have recommended a V osteotomy using the Ilizarov frame and method for
management of foot deformity in poliomyelitis and CMT. In a series of
patients treated in this manner, they documented nearly uniform
achievement of a painless plantigrade foot. It appears that there is a
role for a combination of soft tissue stretching and osteotomy in the
correction of severe deformity using an Ilizarov frame (403).

In l908, Kohler described a condition causing foot pain
in young children in whom radiographic findings of the foot showed
characteristic flattening, sclerosis, and irregular ossification
pattern (404). This is a self-limiting condition, with restitution of healthy bony architecture in all cases.

Kohler disease is more common in boys than in girls, with a ratio of 4:1 (405,406) and is frequently bilateral (406,407).
Tsirikos et al. have reported bilateral Kohler disease in identical
twins, suggesting a genetic predilection for this relatively rare
condition (408).

The etiology of Kohler disease remains unknown, but the
condition is characterized by disordered enchondral ossification
including both osteogenesis and chondrogenesis, presumably related to
mechanical stress at the time of early ossification. Karp (409)
found that ossification of the navicular occurs earlier in girls than
in boys. Half of the girls studied had a navicular that was ossified by
the age of 2 years, and one third of the boys were more than 3½ years
of age by the time ossification occurred. Karp’s feeling was that the
delay in ossification predisposed boys to mechanical injury at the time
of early ossification of the cartilaginous navicular.

In addition to the effects of mechanical stress at the
time of ossification, avascular necrosis appears to play a role in the
development of Kohler disease. The blood supply to the navi-cular bone
is significant, with a network of perichondrial

vessels.
However, at the time of early ossification, arteries penetrate the
cartilaginous navicular without their mature anastomotic network,
predisposing them to vascular injury. Vascular theories are supported
by biopsy studies showing areas of necrosis in the navicular (404).

The typical child with Kohler disease is a young boy,
presenting with an antalgic gait, tending to walk on the lateral border
of the foot. There is often dorsal medial swelling and tenderness, at
times with redness and warmth, which might suggest infection or
arthritis. Range of motion is generally intact.

Standing anteroposterior and lateral x-ray films of the
foot demonstrate characteristic findings of sclerosis, fragmentation,
and flattening of the navicular bone (Fig. 30.64).
The navicular is the last bone in the foot to ossify. The ossific
nucleus is first seen in girls between 18 and 24 months of age and in
boys 30 to 36 months of age (409). Irregularity in ossification is common, with coalescence of early ossification centers (409).
Kohler disease is a clinical diagnosis, rather than a radiologic one;
that is, a patient with irregular ossification pattern does not have
Kohler disease in the absence of symptoms.

Occasional cases are relatively severe, mimicking
infection, and an evaluation including CBC, sedimentation rate, and
C-reactive protein is beneficial. Occasionally an MRI is helpful in
differentiating these conditions. Stress fractures to the tarsal
navicular exist, generally in adults, and avascular necrosis of the
tarsal navicular has been associated with diabetes, but again in
adults, not in young children.

Waugh (410) found two patterns
of blood supply to the navicular. The most common pattern was a diffuse
network of five or six perichondrial vessels. The most common pattern
was a single dorsal or plantar artery. The single vessels at the time
of ossification predispose to mechanical injury and secondary avascular
necrosis. Histologic examination of affected bones demonstrates
necrosis, resorption of dead bone, and formation of new bone consistent
with remodeling after vascular injury.

This is a self-limiting condition with onset in early
childhood. The navicular reconstitutes itself somewhere between 4
months and 4 years of age and is normal at skeletal maturity (405, 406, 407). There is no residual deformity or disability in adults.

Treatment is symptomatic. An over-the-counter arch
support may relieve mild symptoms. For persistent or intense pain, a
short leg cast has been shown to be beneficial. Borges et al. (407), Ippolito et al. (405), and Williams et al. (406)
found that treatment with a below-knee cast for a minimum of 8 weeks
reduced the duration of symptoms. Use of a walking cast was found to be
as effective as use of

a
nonwalking cast. As symptoms were routinely relieved by a short leg
cast in this self-limiting condition, failure to follow the expected
course might be an indication for biopsy. There is, however, no role
for biopsy or surgery in typical cases of Kohler disease.

Sever (411) described a disorder
of the os calcis leading to heel pain in a growing child, which he
thought was an inflammatory disorder. The advent of radiologic imaging
in the early 20th century led Kohler, Freiberg, and many others to the
identification of clinical conditions characterized by similar
radiographic findings called “osteochondroses.”

Sever calcaneal apophysitis is a very common cause of heel pain in immature athletes (412).
The average age at presentation is 11.5 years; it is two to three times
more common in boys than in girls, and 60% of patients have bilateral
involvement (412). As girls become more athletically active, the author suspects that there will be no sexual predilection for this condition.

The cause of Sever apophysitis is unknown. It is considered to be a nonarticular osteochondrosis (413). Repetitive microtrauma and overuse lead to this “apophysitis” in constitutionally susceptible children (412). It appears much like a stress fracture encountered in Osgood-Schlatter disease.

The typical child with Sever apophysitis is a 10- to
12-year-old athletically inclined boy. The patient has pain secondary
to impact as well as repetitive pull of the gastrocsoleus on the
apophysis. The pain is limited to the heel. It may be associated with
warmth, swelling, and even redness. The characteristic finding is pain
with medial lateral compression over the tuberosity of the calcaneus.

It must be differentiated from other causes of heel
pain, which include cystic lesions of the calcaneus and osteomyelitis.
Frequently, children with calcaneal apophysitis have a tight Achilles
tendon.

The diagnosis of Sever apophysitis is a clinical one
because there is no diagnostic radiographic finding. In a review of
radiographs of children with and without Sever apophysitis, sclerosis
appears with equal frequency in the healthy and diseased state.
Fragmentation of the apophysis (414), however, is the radiologic finding seen with increasing frequency in Sever disease (Fig. 30.65).

Other imaging studies: A bone scan may be helpful in
localizing pathology but is generally not needed. An MRI will be
helpful in making the differentiation between disease states involving
the body of the calcaneus and apophysitis. Such conditions include
stress fracture, lytic lesion, or osteomyelitis.

The apophysis of the os calcis is subjected to opposing
forces from the plantar fascia and the Achilles tendon during weight
bearing (413,415,416).
It is also subjected to impact with heel strike in gait. The
combination of direct impact and tension forces from the plantar fascia
and the pull of the gastrocsoleus complex lead to a stress fracture
from repeated microtrauma. Liberson et al. (415)
reviewed the pathology of the apophysis of the os calcis in children.
Their data supported the hypothesis of a stress fracture as a cause of
this injury.

Sever apophysitis is a self-limiting condition that resolves with maturation and the closure of the apophysis of the os calcis.

Treatment of Sever apophysitis is symptomatic. In
general, patients respond to activity restriction and use of a heel pad
in the shoe, making them comfortable. Stretching exercises of the
Achilles tendon may be helpful in decreasing symptoms, and certainly in
decreasing recurrent episodes of Sever apophysitis. Nonsteroidal
antiinflammatory medicines may be of some value. For persistent
symptoms, a short leg cast will relieve pain. With the use of a short
leg cast for patients with symptoms, the average time for relief and
return to activity is 2 months, with the range of time being from 1 to
6 months (412). The recurrence of symptoms is
relatively common in adolescents. There may be some benefit in the
long-term use of heel pads and a heel cord stretching program in the
prevention of recurrence of this condition.

In general, there is no role for surgery in the treatment of Sever apophysitis.

Freiberg (417) described a
painful condition of the second metatarsal head, characterized by
flattening of the articular surface of bone with both lucency and
sclerosis in the metatarsal head. The term “infraction” implied a
traumatic origin, whereas “infarction” would imply an ischemic origin.

The incidence of this condition is unknown, but it
occurs most commonly in adolescent girls and is, surprisingly, the only
“osteochondrosis” with a predilection for the female sex. The second
metatarsal head is most commonly affected, followed by the third. Less
commonly, the first, fourth, and fifth metatarsals are involved. Less
than 10% of individuals have bilateral involvement.

The cause of this disease is unknown, but it is
classified under an osteochondrosis that is characterized by disordered
enchondral ossification. It has been classified by Siffert (413)
as primarily an articular osteochondrosis that may or may not disrupt
the associated epiphysis. Proposed theories for etiology include
trauma, repetitive stress, vascular abnormalities, or high heeled shoes
(418,419).

Typically, girls present with foot pain, exacerbated by
weight-bearing activities or athletics. There is soft tissue swelling
about the metatarsal head and tenderness with restriction of motion on
examination. The differential diagnosis includes arthritis as well as a
metatarsal stress fracture.

The appearance of Freiberg infraction (Fig. 30.66)
is one of increased sclerosis, flattening of the articular surface, and
lucency. It has an appearance somewhat like Perthes disease of the
metatarsal head. The prognosis cannot be accurately determined by the
extent of involvement seen radiographically. Classification systems for
this disease based on radiographic appearance exist (419, 420, 421) but have not been particularly useful in clinical management.

There are three stages of pathologic changes in this condition (422).
Stage 1 is associated with swelling and pain in the absence of
radiologic changes. In stage 2, the cells of the chondrocytes in the
epiphysis die secondary to loss of nutrition by diffusion from joint
fluid or loss of oxygen from blood flow. In stage 3, repair takes place
with gradual replacement of necrotic bone and healing. Intraarticular
loose bodies may complicate the clinical course of Freiberg infraction.

The disease generally progresses through the three
stages as listed in the preceding text, with reconstitution of a
satisfactory articular surface and relief of pain. The long-term
results depend on the severity of the damage to the articular surface
and whether loose bodies result.

Nonoperative treatment is indicated to relieve symptoms
and allow healing of this condition in most cases. Treatments include
avoidance of activity, use of shoe inserts with a metatarsal pad, and
the use of well-padded shoes. Avoiding high-heeled shoes that place
more pressure on the metatarsal heads is advised. Surgery for this
condition generally includes joint debridement and removal of loose
bodies (417,420,423), elevation of a collapsed articular surface with bone grafting (421), excision of a metatarsal head and shortening of a metatarsal (424), and metatarsal dorsiflexion osteotomy (419,420,423).
Debridement of periarticular osteophytes or prominent bone impinging on
metatarsal phalangeal joint motion is a procedure that usually gives
satisfactory symptomatic relief (417,420,423) if required. The distal metatarsal dorsiflexion osteotomy has been reported to relieve symptoms (419,420,425).
In any procedure, it is important to avoid damage to the blood supply
of the metatarsal head at the time of surgery, limiting soft tissue
dissection (419).