Injuries to the Shafts of the Radius and Ulna

The primary mechanism of injury associated with radial
and ulnar shaft fractures is a fall on an outstretched hand that
transmits indirect force to the bones of the forearm.³,⁷⁰,¹⁶⁵
Biomechanic studies have suggested that the junction of the middle and
distal thirds of the radius and a substantial portion of the shaft of
the ulna have an increased vulnerability to fracture.¹⁵⁰
Often, a significant rotational component is associated with the fall,
causing the radius and ulna to fracture at different levels (Fig. 10-8).⁹³,²⁰⁷ If the radial and ulnar fractures are near the same level, a minimal torsional component can be inferred (Fig. 10-9). If comminution is present, higher-energy trauma should be suspected.⁸⁵
Significant hyperpronation forces are associated with isolated shaft
fractures of either the radius or the ulna and concomitant dislocation
of either the distal or the proximal radioulnar joint. Thus, in any
single-bone forearm shaft fracture, these important joints need to be
closely scrutinized. Galeazzi and Monteggia fracture-dislocations are
discussed in Chapters 9 and 12, respectively.

A direct force to the arm (such as being hit by a
baseball bat) can fracture a single bone (usually the ulna) without
injury to the adjacent distal or proximal radioulnar joints.³⁶
Isolated ulnar shaft fractures have been referred to as “nightstick
fractures.” Alignment of the radial head should be confirmed in

any child with such a fracture to avoid a “missed Monteggia” injury.¹⁴⁸ Isolated radial shaft fractures are rare but notoriously difficult to reduce with closed methods.⁶⁸,⁹² Rang²⁶³
referred to apex volar greenstick fractures of the distal radial shaft
near the metaphysis as “the slipper” because of its annoying tendency
to lose position after otherwise satisfactory reduction.

The mechanisms of injury of two particular forearm
fracture patterns, traumatic bowing (also known as bow fractures or
plastic deformation)²⁶³ and
greenstick fracture, also bear mentioning. Bone behaves differently
based on the direction of the forces applied to it. This is the
so-called anisotropic property of bone, and it can be simply explained
as follows: bone is more resistant to axial forces than to bending and
rotational forces.⁵⁴ Pediatric bone
also is much more porous than its adult counterpart and behaves
somewhat differently from a biomechanic standpoint.⁵⁷,²³² Because of its porosity, pediatric bone absorbs significantly more energy prior to failure than does adult bone.⁷⁵
When relatively slowly applied, longitudinal forces bend immature bone
beyond its elastic limits and into its plastic zone, resulting in
traumatic bowing.⁴⁰,¹⁹⁸
Thus, when a bending force is applied relatively slowly, many
microfractures occur along the length of the bone, leading to
macroscopic deformity without discernible radiographic fracture. This
bending can usually be seen radiographically if suspected.

Greenstick fractures represent an intermediate step between plastic deformation and complete fractures.⁵⁵
On anteroposterior (AP) and lateral radiographs, greenstick fractures
show cortical violation of one, two, or three of their radiographic
cortices, and thus some bony continuity is preserved. Rotational
deformity is considered to be intimately related to the clinical
deformity seen with greenstick fractures of the forearm, and the
analogy of a cardboard tube that tends to bend as it is twisted has
been offered by Holdsworth.¹⁴⁴
Specifically, hyperpronation injuries usually are associated with
apex-dorsal greenstick fractures of the forearm, and hypersupination
injuries usually are associated with the opposite, apex-volar injuries.⁹²,²²⁰ The treatment of these greenstick fractures requires a derotation maneuver in addition to correction of any angulation.⁵⁵,¹³³

The signs and symptoms indicating fracture of the shafts
of the radius and ulna usually are not subtle. Deformity and pain are
the classic findings. Patients typically experience exquisite pain
emanating from the involved area. Decreased pronation and supination
motion are also usually noted.³⁰⁸
Neither practitioners nor parents are always reliable assessors of
children’s pain, and ideally patients should rate their own pain.¹⁷⁰,³⁰¹ Significant anxiety and muscle spasm almost always amplify a child’s painful experience.⁴⁹,¹¹⁶
It has been suggested that muscle spasm is a protective effort by the
body to splint or otherwise protect the injured body part.¹¹⁶
When such muscle spasm occurs in association with certain fracture
patterns (e.g., a radial shaft fracture proximal to the pronator teres
insertion), it produces

predictable fracture displacement (e.g., a pronated distal radial fragment and a supinated proximal fragment).

More subtle fractures present special diagnostic
challenges. Certain pathologic fractures of the forearm may occur in
the absence of overt trauma.¹⁵⁶,¹⁷⁸
Many minimally displaced fractures of the shafts of the radius and ulna
can be mistaken for a “sprain” or “just a bruise” for several days to
several weeks. This usually occurs in young children who continue to
use the fractured arm during low-level play activities. As a general
rule, a fracture should be suspected if the child has not resumed all
normal arm function within 1 or 2 days of injury.

Most fractures of the shafts of the radius and ulna
occur as isolated injuries, but wrist and elbow fractures may occur in
conjunction with forearm fractures, and the elbow and wrist region
needs to be included on standard forearm radiographs.²⁷,⁷⁶,¹⁶⁵,³⁵³,³¹³,³⁵⁹
If clinical suspicion is high, then dedicated wrist and elbow films are
necessary. The so-called floating elbow injury (fracture of the bones
of the forearm along with ipsilateral supracondylar humeral fracture)
is a well-described entity that must not be missed.²⁷,²⁷²,³¹³,³⁵³
Surgical stabilization of both the supracondylar fracture and the
forearm fractures has been recommended by multiple authors in recent
years³¹,¹³⁸,²⁷¹,²⁷²,³¹⁸,³²¹
to avoid the risk of a compartment syndrome. Galeazzi and Monteggia
fracture-dislocations also must be ruled out. Compartment syndrome also
can occur in conjunction with any forearm shaft fracture.⁷⁴,³⁶³
This rare but potentially devastating complication can lead to a
Volkmann ischemic contracture, which has been shown to occur after
forearm shaft fractures almost as often as it does after supracondylar
humeral fractures in children.²²¹
Patients with severe pain unrelieved by immobilization and mild
narcotic medication should be reassessed for excessive swelling and
tight forearm compartments. If loosening of the splint, cast, and
underlying cast materials fails to relieve pain, then measurement of
compartment pressures and subsequent fasciotomy may be necessary.

Abrasions or seemingly small unimportant lacerations
that occur in conjunction with forearm fractures must be carefully
evaluated because they may be an indication of an open fracture. Clues
to the presence of an open fracture include persistent slow bloody ooze
from a small laceration near the fracture site and subcutaneous
emphysema on injury films. Careful evaluation and, in some situations,
sterile probing of suspicious wounds will be necessary. Open forearm
fractures are discussed later in this chapter.

Vascular or neurologic injuries rarely are associated
with forearm shaft fractures, but the consequences of such injuries are
far-reaching. Serial neurovascular examinations should be performed and
documented. Radial and ulnar pulses along with distal digital capillary
refill should be routinely evaluated. Davis and Green⁸⁰
reported nerve injuries in 1% (5/547) of their pediatric forearm
fracture patients, with the most commonly injured nerve being the
median nerve. Combined data from three large series of pediatric open
forearm fractures reveal an overall nerve injury rate at presentation
of 10% (17/173), with the median nerve once again being the one most
commonly injured.¹²⁸,¹³⁵,¹⁹⁵
To screen for these rare but significant injuries, every child with a
forearm fracture should routinely have evaluation of the radial, ulnar,
and median nerves.⁶⁸ Nerve injuries occurring at the time of injury must be differentiated from treatment-related or iatrogenic neurologic deficits.

Davidson⁷⁹ suggested using the game of “rock-paperscissors” for testing the median, radial, and ulnar nerves (Fig. 10-10). The pronated fist is the rock and tests median nerve

function. The extended fingers and wrist depict paper and test radial
nerve function. Fully flexed small and ring fingers, an adducted thumb,
and spreading the index and ring fingers mimic scissors and test ulnar
nerve function. Further focused testing should also be done on two
important nerve branches: the anterior interosseous nerve (branch of
median nerve) and the posterior interosseous nerve (branch of radial
nerve). The anterior interosseous nerve provides motor function to the
index flexor digitorum profundus, the flexor pollicis longus, and
pronator quadratus and is best tested by having the patient make an
“OK” sign. The posterior interosseous nerve typically innervates the
extensor carpi ulnaris, extensor digitorum communis, extensor digiti
minimi, extensor indicis, and the three out-cropping muscles of the
thumb (abductor pollicis longus, extensor pollicis brevis, and extensor
pollicis longus).⁴⁵
Its function is best documented by full extension of the phalangeal and
metacarpophalangeal joints. This is especially difficult to test in a
patient in a cast or splint that partially covers the fingers. Most
injuries that occur in association with forearm fractures are true
neurapraxias and typically resolve over the course of days to weeks.⁷⁴,⁸⁰

Fractures of the shafts of the radius and ulna often are
described in rather imprecise terms such as “both-bone forearm
fracture” and “greenstick fracture.” Radiographs confirm the diagnosis
of forearm shaft fracture and are the basis for most classification
systems. The most comprehensive classification of forearm fractures is
the one adopted by the Orthopaedic Trauma Association (OTA).¹² Although this system is sound in concept, its 36 discrete subtypes¹² make it impractical for everyday clinical use, and it has not been widely used by clinical researchers.²⁶⁹
Despite its complexity, the OTA classification does not account for one
of the most important prognostic factors in pediatric forearm shaft
fracture: location of the fracture in the distal, middle, or proximal
third of the shaft.

Clinicians and clinical researchers have favored simpler
descriptions of forearm shaft fractures. An orderly and practical
approach to forearm shaft fracture classification should provide
information about the bone (single bone, both bones), the level
(distal, middle, or proximal third), and the pattern (plastic
deformation, greenstick, complete, comminuted). Bone involvement is
important because it not only indicates the severity of injury but also
influences suspicion regarding additional soft tissue injury (e.g.,
single-bone injury increases the likelihood of a Monteggia or Galeazzi
injury)³³⁵ and affects reduction tactics (unique single-bone fracture reduction strategies can be used) (Fig. 10-11).
Single-bone shaft fractures occur, but both-bone fractures are more
common. Level is important for anatomic reasons relative to muscle and
interosseous ligament attachments,

as
well as differences in prognosis for distal-, middle-, and
proximal-third shaft fractures. Pattern is important because it
significantly alters the treatment approach. For example, the primary
reduction strategy is very different for greenstick fractures
(rotation) compared to that for complete fractures (vertical traction).
Certain comminuted fractures (e.g., comminution of both bones) may
preclude reduction and casting and require plate fixation.¹⁰³,¹⁰⁴
Fortunately, comminuted fracture patterns are rare in children. For all
practical purposes, the buckle fracture pattern that is common in the
distal radial metaphysis never occurs in isolation in the shaft region.
The typical buckle fracture “speed bump” may accompany either plastic
deformation or greenstick fractures. Thus, there are two bones, three
levels, and four common fracture patterns (Fig. 10-12). We believe this is a practical and clinically relevant way to describe forearm shaft fractures.²¹¹

Once the forearm fracture has been described in the
terms of this practical classification, fracture displacement must be
evaluated. Fracture displacement can occur as angulation, rotation,
shortening, or translation. Angulation is important in treatment
decision-making and can be measured with reasonable reliability.¹⁸⁵,³¹⁹ Rotation is a simple concept, but it is difficult to assess clinically.⁹³,²⁵⁵ The best that usually can be done is to roughly estimate rotation within a 45-degree margin of error.⁷²,²⁵⁵
Based on available clinical studies, it appears that less than 1 cm of
shortening should be accepted in either single-bone or both-bone
fracture patterns.⁵³,⁸¹,⁸⁶,²¹³,²⁷³
It also has been suggested that the shortening that accompanies
displaced fractures may help preserve future motion through
interosseous membrane relaxation.²⁵⁵ Translation also is a simple concept and can be easily measured. Completely (100%) translated fractures of the middle third⁷²,²⁵⁵ and distal third⁸⁶,²¹³,²⁷³
of the forearm have been shown to reliably remodel. Certain situations
may raise concern regarding complete translation, such as isolated
middle-third radial fractures with medial (ulnar) displacement that
significantly narrows the interosseous space and translation in
children who have less than 2 full years of growth remaining, because
remodeling of the translated fracture site is less predictable than in
younger children.²³⁰,²³²

The fundamental reason for treating fractures of the
shafts of the radius and ulna relates to the likelihood of bad results
in the absence of adequate care. Data from certain developing countries
may be as close as we come to natural history studies of untreated
fractures. Archibong and Onuba¹⁴
reported on 102 pediatric fracture patients treated in southeastern
Nigeria. Their patients most commonly had upper extremity fractures,
and they frequently experienced significant delays in seeking medical
treatment, which led to high rates of malunion requiring surgical
treatment.¹⁴ Other Nigerian authors
have found that young age was not protective against fracture malunion
(more than 50%) and nonunion (25%) following traditional bonesetter

treatment.²³⁶
It is unclear whether children treated in this fashion are better or
worse off than if they had received no treatment at all. The rationale
for treating pediatric forearm shaft fractures is thus based on the
premise that the results of modern orthopaedic treatment will exceed
“pseudonatural histories” such as these.

The consequences of excessively crooked (and malrotated) forearm bones are both cosmetic and functional (Fig. 10-13).²⁹,³⁵,¹⁴⁴,²⁰⁶,²²⁹,³²⁹ Limited forearm supination following a forearm shaft malunion is illustrated in Figure 10-14.
Despite their great concern to parents, cosmetic issues have not been
formally studied, and as a result the practitioner must interpret
forearm cosmetic issues on a case-by-case basis. Clinical experience
has shown that the ulna appears to be less forgiving from a cosmetic
standpoint because of its long subcutaneous border. Early and repeated
involvement of the parents (or other legal guardians) in an informed
and shared decision-making process is essential.

Bony malunion and soft tissue fibrosis have both been
implicated as causes of limited forearm motion after forearm shaft
fractures.¹⁴³,²²⁹ Limited forearm pronation and supination can have significant effects on upper extremity function.²⁷,²⁴³,²⁵⁵
Inability to properly pronate often can be compensated for with
shoulder abduction, but no easy compensatory mechanism exists for
supination deficits.⁶⁸,¹⁴⁴,²⁴³,²⁵⁵ Daruwalla⁷⁶
identified a nearly 53% rate of limited forearm rotation (subtle in
some, dramatic in others) in his series of 53 children with forearm
fractures and attributed it to angular deformity and rotational
malalignment. Several patients in Price’s²⁵⁵
classic series of pediatric forearm malunions had severe forearm
range-of-motion losses that significantly limited vocational and
avocational activities. Trousdale and Linscheid³²⁹
reported range-of-motion losses severe enough to prompt corrective
osteotomies in many of their predominantly pediatric (less than 14
years old at time of injury) patients with forearm malunions. Meier²¹⁴ also reported significant range-of-motion deficits in association with pediatric forearm malunion.

Range-of-motion losses due to deformity have been
studied by numerous authors using adult cadaveric forearm specimens.
Matthews et al.²⁰⁶ studied 10- and
20-degree midshaft angular deformities of the radius and ulna in 10
forearm specimens. They found that 10-degree deformities of either bone
individually resulted in little or no measurable motion loss (in the
range of 3 degrees or less). When both bones were angulated 10 degrees
dorsal, volar, or toward the interosseous membrane, larger motion
losses were documented (approximately 10 degrees pronation and 20
degrees supination). Significantly greater losses of motion occurred
when one or both bones were angulated 20 degrees (approximately 40
degrees for both pronation and supination). Some of the 10-degree
angulated specimens demonstrated “cosmetically unacceptable deformity.”²⁰⁶ These findings indicate that relatively small angular deformities can be clinically significant.

Additional important information about the influence of
fracture level on forearm motion was provided by a series of
experiments conducted by Sarmiento et al.²⁸⁰,³²⁰
They found that fracture angulation of 15 to 30 degrees led to greater
supination losses when the deformity was in the middle third of the
forearm (40 to 90 degrees) and greater pronation losses when in the
distal third (30 to 80 degrees).³²⁰
Fracture angulation of 10 degrees or less in the proximal or middle
forearm rarely resulted in more than 15 degrees of motion loss,²⁸⁰,³²⁰ but the same angulation in the distal third of the forearm was at times

(usually with isolated radius fracture) associated with pronation losses of 20 degrees.²⁸⁰,³²⁰
These findings challenge commonly held beliefs that the distal third of
the forearm is the most forgiving. These same authors asserted that
rotational malalignment led to rotational motion losses that usually
were equal in magnitude and opposite in direction to the deformity
(e.g., a 10-degree pronation deformity led to a 10-degree loss of
supination).³²⁰

Rotational malalignment of the forearm has been studied in greater detail in recent years.⁸⁸,¹⁶⁷,³³¹
In isolated midshaft radial fractures, more than 30 degrees of
malrotation was a threshold for significant losses in motion
(approximately 15 degrees).¹⁶⁷
Isolated midshaft ulnar fracture malrotation did not alter the total
arc of forearm motion but did change the set point (e.g., a 30-degree
pronation deformity took away 30 degrees of pronation and added 30
degrees of supination).³³¹ Larger ulnar axial malalignment of 45 degrees decreased overall forearm rotation by no more than 20 degrees.³³¹ Large residual ulnar shaft translation has similarly been found to have little impact on forearm rotation.²⁰⁹ Simulated combined radial and ulnar midshaft rotational

malunions resulted in the worst motion (more than 50% losses of
pronation and supination when 60-degree rotational malunions were in
opposite directions).⁸⁸ Rotational malunions that approximated recommended limits in the literature (45 degrees)²⁵⁵ produced less extreme but real limitations of motion (Table 10-1).⁸⁸
From these studies and our clinical experience, it appears that the
radius is more sensitive to rotational problems and less sensitive
regarding cosmetic issues, while the ulna is exactly the opposite.

Several generations of orthopaedic surgeons have been
taught that 50 degrees of pronation and 50 degrees of supination
represent adequate forearm motion.²¹⁹
It must be remembered that this classic study performed by Morrey and
his Mayo Clinic colleagues involving 33 normal subjects (18 female, 15
male) from 21 to 75 years of age is not the only study that addresses
forearm motion. The average arc of normal forearm motion for the Mayo
group (68 degrees pronation to 74 degrees supination)²¹⁹
was approximately 20 degrees less than that measured in 53 healthy male
subjects who were no older than 19 years old (77 degrees pronation to
83 degrees supination) by Boone and Azen³⁹ and 35 degrees less than that reported by Rickert et al.²⁷⁰
(75 degrees pronation to 100 degrees supination) in 141 subjects of
both sexes between 20 and 30 years of age. Contemporary
three-dimensional motion analysis has revealed that maximal pronation
occurs when pouring liquid from a pitcher and maximal supination
commonly occurs during personal hygiene activities.²⁶¹ Thus, it seems clear that the forearm motion “goals” reported by Morrey et al.²¹⁹
are not necessarily ideal or even optimal, but rather they may be
considered as the minimal limits of forearm function. Stated another
way, losing 20 degrees or 30 degrees of either pronation or supination
carries the potential for significant functional impact upon important
activities of daily living.

The goal of treatment is to achieve satisfactory healing
of the forearm injury within established anatomic and functional
guidelines while also taking into account the reasonable degree of
remodeling that can be expected in growing children.¹⁵⁴
Most of the time, these goals can be achieved with closed fracture
care, and little or no radiographic or clinical abnormality can be
detected following healing. A paradox exists in pediatric forearm
fractures whereby anatomic radiographic alignment is not always
associated with normal motion, and normal motion often is associated
with nonanatomic radiographic healing.¹⁴³,²²⁵,²²⁹,³²⁰ Herein lies the inherent controversy between operative and nonoperative treatment approaches (Table 10-2).
In patients with anatomic radiographs, range-of-motion problems usually
have been attributed to scarring of the interosseous membrane.¹⁶⁸,²⁴³,²⁵⁵
With nonanatomic radiographs (incomplete remodeling), range-of-motion
deficits usually are attributed to the radiographic abnormalities.
Thus, treatment of forearm shaft fracture must balance the risk of
allowing stiffness to occur secondary to malunion against the risk of
creating stiffness secondary to surgical procedures.

The rationalization for remodeling of pediatric forearm fractures has strong historical support,²³,³⁶,⁵¹,²³⁹
but knowledge of the limits of remodeling must be taken into
consideration. Established reduction criteria state that complete
(100%) translation is acceptable,²¹³,²⁵⁵ as well as up to 15 degrees of angulation and up to 45 degrees of malrotation.²⁵⁵
Because important forearm fracture treatment decisions frequently are
based on radiographic measurement of angular deformities, it must be
remembered that these angles are projected shadows that are affected by
rotation.¹⁰² If angulation is
present on both AP and lateral views (commonly called two orthogonal
views), the true deformity is out of the plane of the radiographs, and
its true magnitude is greater than that measured on each individual
view. Certain forearm shaft fracture deformities are clearly “twoplane
deformities” whose maximal angular magnitude is in some plane other
than the standard AP or lateral plane (Fig. 10-15).¹⁷ Bär and Breitfuss¹⁷
produced a table (based on the Pythagorean Theorem) that predicts the
true maximal angulation. Accurate deformity measurement can be made
when angulation is seen on only one view and there is no angulation on
the other orthogonal view. A cast change with molding, remanipulation
under analgesia or anesthesia, or surgical fixation may become
necessary, but even with anatomic reduction patients may not regain
full pronation and supination.²²⁹,²⁴³ Most series of pediatric forearm fractures document excellent subjective results, and

only with special goniometric testing is a decreased range of motion detected objectively.⁷²

Published clinical studies have shown that pediatric
forearm shaft fractures have great remodeling potential that occurs
through several mechanisms.²⁸⁹ The
distal radial epiphysis will redirect itself toward normal at about 10
degrees per year. As long as the physis is open, this rate is
independent of age. Although the epiphysis will return to normal
direction, it will have much less effect on correcting an angular
deformity at the midshaft compared to fractures at the subphyseal
level. Remodeling also occurs with lengthening of the bone through
growth, which produces an apparent decrease in angulation, especially
if measured as the difference between the proximal and distal ends of
the bone. Bone also remodels by intramembranous apposition on the
concave side and resorption on the convex side.⁷⁵,¹⁵⁴,²⁸⁹ This occurs throughout life, but more rapidly when driven by the thick periosteum found in children. Larsen¹⁸²
found that although the epiphyseal angle realigns quickly, children
older than 11 years correct bone angulation less than the younger
children. Thomas stated the following regarding pediatric forearm
remodeling potential: “We should not fail to recall that the remodeling
capabilities of the bones of children have not changed in the last
million years and that open reduction and internal fixation must be
undertaken only after due deliberation.”³²² Others such as Ashok Johari¹⁵⁷
would state that if one critically evaluates the limits of forearm
shaft remodeling capacity you will find a much higher rate
(approximately 50%) of incomplete remodeling in children over 10 years
of age.

The forearm is a large nonsynovial joint with nearly a
180-degree arc of motion. Its bones, the radius and ulna, are not
simple straight bony tubes. The shaft of the radius is a three-sided
structure with two prominent curvatures. One major gradual convexity
(approximately 10 degrees with its apex lateral-radial) is present
along its midportion; a second, more acute curve of approximately 15
degrees with its apex medial occurs proximally near the bicipital
tuberosity.¹⁰⁰,¹²⁷,²⁷⁷
The deviation along the midportion is commonly referred to as the
radial bow, and maintenance of this normal contour is a goal of forearm
shaft fracture care.²⁵⁹,²⁸⁴,²⁸⁵
The most important bony landmarks of the radius are the radial styloid
(lateral prominence) and the bicipital tuberosity (anteromedial
prominence), which are oriented somewhat less than 180 degrees away
from each other (Fig. 10-16).²¹⁷ Anthropologists consider a full 180-degree relationship to be characteristic of Neanderthal osteology.³²⁷
Maintenance of the styloid-tuberosity rotational relationship is
another forearm shaft fracture principle. The nutrient artery of the
radius enters the bone in its proximal half and courses anterior to
ulnar (medial).¹¹⁹ Such nutrient
vessels typically are seen on only one orthogonal view and should not
be confused with fracture lines. In cross section, most of the shaft of
the ulna also is shaped like a classic three-sided prism, while its
more distal and proximal portions are much more circular. The most
important bony landmarks of the ulna are its styloid process (distally)
and its coronoid process (proximally). These two landmarks are oriented
nearly 180 degrees from one another, with the styloid aimed in a
posterior (dorsal) direction and the coronoid in an anterior (volar)
direction.²¹⁷ Tracking
styloid-coronoid rotational alignment of the ulna is another part of
forearm shaft fracture care. The ulnar shaft has mild curvatures in
both its proximal (apex lateral/radial) and distal (apex medial/ulnar)
portions but is otherwise relatively straight.¹²⁷,²⁷⁷ The nutrient artery to the ulna enters the bone in its proximal half and courses anterior to radial (lateral).¹¹⁹

The classic works of Evans helped focus attention on rotational

deformity associated with fractures of both bones of the forearm.⁹⁴,²⁰⁷,²⁶³
Evans stated, “The orthodox position in which to immobilize these
fractures is that of full supination for the upper third, and the
midposition for fractures of the middle and lower thirds, these
positions being based on the anatomical arrangement of the pronators
and supinators of the forearm. However, it is unreasonable to suppose
that all fractures at a given level will present the same degree of
rotational deformity.”⁹⁴ He pointed
out the importance of tracking the rotational alignment of the
free-moving radial fragment by ascertaining the relative location of
the bicipital tuberosity. This was a major step forward in refining the
orthopaedic care of these forearm injuries. On a fully supinated AP
radiograph of an unfractured forearm, the bicipital tuberosity points
predominantly in a medial direction (nearly 180 degrees opposite of the
radial tuberosity).⁹⁴ The radius and
ulna also are nearly parallel to each other on such a view. On a fully
pronated AP radiograph of an unfractured forearm, the bicipital
tuberosity points in a lateral direction and the radial tuberosity is
situated medially.⁹⁴ The radius also crosses over the ulna in a pronated AP view. Rang²⁶² noted that in an unfractured limb, the bicipital tuberosity tended to align with a point near the thenar eminence (Fig. 10-17),
more nearly a 165-degree relationship than a true 180-degree one. These
relationships are best assessed on standard radiographs that include
the entire forearm on one film⁷⁶,²⁵⁵,³²⁹ rather than the specialized bicipital tuberosity view originally suggested by Evans.⁹⁴

Some generalities regarding the appearance and closure
of secondary ossification centers of the radius and ulna should be kept
in mind because these growth areas must be respected during both
surgical and nonsurgical fracture care.²⁴⁴,²⁵⁶,³⁶⁴,³⁶⁵ The secondary center (epiphysis) of the distal radius is the first to appear at around 1 year of age.³²,²³³ Next are the epiphyses of the proximal radius and distal ulna, which appear by about 4 to 6 years of age.²⁹⁹ The proximal ulna is last and appears at around 9 years of age.²⁹⁸
Physeal closure occurs in two stages, with the proximal radius and
proximal ulna closing by about 15 years of age and the distal radius
and ulna by about 18 years of age.²³¹ It must be remembered that females’ physes close 1 to 2 years before their male counterparts.

The radius and ulna are joined by three major passive
restraints: the proximal radioulnar joint (PRUJ), the distal radioulnar
joint (DRUJ), and the interosseous membrane complex, all of which have
important stabilizing and load-transferring functions. These structures
allow rotation of the radius about the ulna along an axis that runs
approximately from the center of the radial head to the center of the
distal ulna.¹⁴⁵,²⁴³ The PRUJ and DRUJ are discussed elsewhere in this book (Chapters 9 and 11).
The structure and biomechanic function of the interosseous membrane
have been studied extensively in recent years. Hotchkiss et al.¹⁴⁹
showed that the central band of the interosseous membrane (the
interosseous ligament) courses from a point near the junction of the
proximal and middle thirds of the radius to a point near the junction
of the middle and distal thirds of the ulna. It is an important
longitudinal stabilizer of the forearm in that 71% of forearm
longitudinal stiffness is provided by the interosseous ligament after
radial head excision.¹⁴⁹ Transverse vectors also have been identified²⁴⁶
and reflect the stabilizing effect of the interosseous ligament during
pronation and supination movements. The interosseous ligament
demonstrates tensile properties comparable to the patellar tendon and
the anterior cruciate ligament,²⁴⁷ indicative of the magnitude of the arm forces to which this structure is subjected.

Although some difference of opinion still exists,⁸²,¹⁰⁹,³⁰⁴
multiple studies have shown that the most strain in the central band of
the interosseous membrane is generated when the forearm is in the
neutral position.²⁰³,²⁰⁴,³⁰⁴ These findings of maximal strain in neutral in cadaver studies also are consistent with radiographic measurement studies⁷²
and dynamic magnetic resonance imaging studies of the forearm showing
that the interosseous space is maximal near a neutral position.²²⁶ This may help explain certain pathologic situations such as the fixed supination deformity of neonatal brachial plexus palsy²⁰⁸ as well as limitations of pronation and supination due to encroachment on the interosseous space from malangulated fractures (Fig. 10-18).³⁶⁰
The interosseous membrane also serves as an important anchoring point
for several forearm muscles: the flexor digitorum profundus, flexor
pollicis longus, extensor indicis, and the outcropping muscles
(extensor digitorum brevis, abductor pollicus longus).

The paired and seemingly balanced radial and ulnar bones
have an unbalanced number of muscular connections. The ulna typically
has 14 attached muscles and the radius only 10 (Tables 10-3 and 10-4).⁸⁷,¹²⁷
Powerful supinators attach to the proximal third of the forearm, while
important pronators attach to its middle and distal thirds (Fig. 10-19).
The accompanying vasculature of the forearm is complex: these muscles
are supplied by more than 248 vascular pedicles arising from the
brachial artery, its branches, or other collateral vessels.²⁶⁸ The radial, ulnar,

and median nerves (or their branches) along with the musculocutaneous
nerve provide all of the key innervations to the motors that attach to
the forearm bones. As mentioned earlier, the median nerve is the most
commonly injured nerve with forearm fractures.⁷⁹,⁸⁰,¹²⁸,¹³⁵

The radial nerve proceeds from a posterior to anterior
direction and enters the forearm after passing the lateral epicondyle
between the brachialis and brachioradialis muscles. Near this same
level, it divides into superficial and deep terminal branches. The deep
motor branch of the radial nerve also is known as the posterior
interosseous nerve. In addition to its routine innervation of the
brachioradialis and extensor carpi radialis longus, most commonly (55%
of the time) a motor branch arises from the radial nerve proper or its
superficial terminal branch to innervate the extensor carpi radialis
brevis, while the rest of the time (45%) this motor branch comes from
the posterior interosseous nerve.²
The superficial branch travels along with and beneath the
brachioradialis. The posterior interosseous nerve enters the supinator
muscle, passing the fibrous thickening called the arcade of Frohse
shortly after branching from the radial nerve proper. It courses within
the supinator past the proximal radius, later exiting this muscle
dorsally (posteriorly) near the junction of the proximal and middle
thirds of the radius. Following its emergence from the supinator, the
posterior interosseous nerve branches repetitively to the superficial
extensors and the deeper outcropping muscles. The ulnar nerve enters
the forearm between the two heads of the flexor carpi ulnaris.¹²¹
It traverses the forearm between the flexor carpi ulnaris and the
flexor digitorum profundus. In the distal forearm, it lays just beneath
the flexor carpi ulnaris. The median nerve enters the forearm as it
passes between the two heads of the pronator teres.⁵⁹
It next passes beneath the archway created by the two heads of the
flexor digitorum superficialis. The median nerve then continues down
the course of the forearm nestled between the flexor digitorum
superficialis and the flexor digitorum profundus. It becomes much more
superficial as it nears the level of the carpal tunnel. The anterior
interosseous branch arises from the median nerve at the level of the
pronator and travels deep with the anterior interosseous vessels.
Abundant muscle shields the radial, ulnar, and median nerves from the
shafts of the radius and ulna through most of the forearm.

The large exposure required for plate fixation of
pediatric forearm fractures can be achieved with three surgical
approaches: the Henry (anterior) and Thompson (posterior) approaches to
the radial shaft and the direct (medial) approach to the ulnar shaft.⁷³,²²³ Compartment syndrome release usually requires the serpentine incision of McConnell’s combined approach.¹⁴¹ These approaches and their variations are well described and illustrated in detail elsewhere.⁵,¹⁹,⁹⁰,¹⁴⁷,²⁹⁶
For open reduction of both the radius and the ulna, most authors favor
separate incisions to minimize the possibility of communicating
hematoma and the development of a radioulnar synostosis.¹⁸⁰,²⁵⁹,³³³ The Thompson approach to the radius generally is used for fractures of its proximal third³⁵⁸ but requires special care to protect the posterior interosseous nerve.⁸⁴,²¹⁵,³¹⁷ Other authors have emphasized the utility of the Henry approach for plating of the proximal radius.²¹⁵
When open reduction is done in conjunction with other internal fixation
techniques (e.g., intramedullary fixation), limited versions of the
same surgical approaches are used.

Indirect reduction and internal fixation of forearm
fractures requires knowledge of appropriate physeal-sparing entry
portals about the distal and proximal forearm. Because of the relative
inaccessibility of its proximal end, the radius usually is approached
only distally through either a dorsal or radial entry point. The dorsal
entry point is near the proximal base of Lister’s tubercle or just
lateral to it in a small bare area between the second and third dorsal
compartments. This location is a short distance proximal to the physis
of the distal radius. Another dorsal alternative is pin entry just
medial to Lister’s tubercle, between the third and fourth dorsal
compartments,²⁷⁵ but this may entail
greater tendon risk. The most commonly used radial entry point is
located in line with the styloid process just proximal to the physis.³⁵⁶
Entry in this area passes adjacent to the first dorsal compartment, and
thus the tendons of abductor pollicis longus and extensor pollicis
brevis (as well as branches of the superficial radial nerve) must be
protected (Fig. 10-20). Because of its
extensive branching pattern, portions of the superficial branch of the
radial nerve may be at risk when dorsal or radial intramedullary entry
points are used.¹,¹⁶

Both distal and proximal intramedullary entry sites for the ulna have been described.¹⁸⁸,¹⁹⁴,²⁵⁴,²⁹⁷,³³⁷
In the distal portion of the ulna, an entry site can be made proximal
to the physis and in the interval between the extensor carpi ulnaris
and flexor carpi ulnaris tendons. Care must be taken to avoid branches
of the dorsal cutaneous sensory nerve. Ulnar entry is most easily
accomplished in the proximal portion of the bone along its lateral
metaphyseal border (just distal to the olecranon apophysis),

piercing peripheral fibers of the anconeus (Fig. 10-21).⁴⁸,¹⁸⁴,¹⁹¹
This anconeus entry site described by the Nancy group avoids the physis
and avoids the painful bursa that tends to form over “tip of the
olecranon” pins.

Transphyseal approaches to both the distal radius³⁶⁴,³⁶⁵,³⁶⁶ and the proximal ulna¹⁰,²¹⁵,¹⁹⁴
have been suggested by some authors. Significant growth potential
exists at the distal radius (approximately 10 mm per year), while there
is proportionately less from the olecranon apophysis (approximately 2
mm per year). There is an unnecessary risk to the radial physis and few
if any technical advantages to transphyseal entry of the radius in
diaphyseal level fracture fixation. The ulna apophyseal entry site is
used in many centers.

Most pediatric radial and ulnar shaft fractures can be treated by nonoperative methods.³⁶⁶
Low-energy, undisplaced, and minimally displaced forearm fractures can
be immediately immobilized in a properly molded (three-point mold
concept of Charnley) above-elbow cast.¹⁰
If posttraumatic tissue swelling is a concern, noncircumferential
splint immobilization (e.g., sugar tong splint) can be used initially.⁶⁸,³²⁴,³⁶²
For fractures in the distal third of the forearm, below-elbow casting
has been shown to be as effective as above-elbow casting in maintenance
of satisfactory fracture alignment.⁶³,¹¹²
Appropriate follow-up is important for these undisplaced fractures (an
initial follow-up radiograph usually is taken 7 to 14 days after
injury) because displacement may still occur for a variety of reasons:
new trauma to the extremity, male gender, and poor casting technique.⁶⁸,¹¹³,²⁹⁰,³⁶²

Good casting technique is infrequently discussed in
contemporary orthopaedic textbooks and sometimes is underemphasized
during orthopaedic residency training. The principles of good forearm
casting technique include: (a) interosseous molding, (b) supracondylar
molding, (c) appropriate padding, (d) evenly distributed cast material,
(e) straight ulnar border, and (f) three-point molding (Fig. 10-22).
The risk of excessive cast tightness can be minimized through the use
of the stretch-relax fiberglass casting technique described by Davids
et al.⁷⁷ Chess et al.⁶³
described a cast index for distal radial fractures defined as the
sagittal cast width divided by the coronal cast width at the level of
the fracture site; a normal ratio is considered to be 0.70. The cast
index has not been validated for forearm shaft fractures, but it
embodies the sound concept of good interosseous molding. Advanced
techniques such as pins and plaster and cast wedging also have a role
to play.¹⁸,⁸⁹ Cast wedging is almost always done with an opening wedge technique because this entails less risk of soft tissue impingement.¹⁶⁹

Displaced fractures usually require reduction following appropriate analgesia.⁸⁶,³³⁴ Options include hematoma block,¹⁰⁷,¹⁴⁰,¹⁵⁹ regional intravenous anesthesia,⁴⁶,⁷⁸,¹⁶³ and inhalational methods.⁹⁵,¹²⁹,¹⁴⁰
After informed consent for the sedation and reduction is obtained,
monitored sedation can be used in the emergency department with a
combination of narcotics and anxiolytics.¹⁷³ This typically requires a dedicated nurse to administer oxygen and perform appropriate monitoring functions

(vital signs, continuous electrocardiogram, and pulse oximetry).⁸,⁹,¹⁴² Ketamine protocols also are being used with increased frequency.¹²⁰,¹⁷³
Young children with less than 5 or 10 degrees of angulation in the
plane of wrist and elbow motion probably do not require the additional
trauma, time, expense, and sedation risk involved in a formal reduction
because of the predictable remodeling in this age group.¹⁴
It has been shown that the more displaced the fracture, the more likely
that formal monitored sedation techniques will be used for pediatric
forearm fracture reduction as opposed to other techniques.³³⁴

More specific closed treatment options are discussed for
pediatric forearm injuries in terms of their common fracture patterns:
bow (plastic deformation), greenstick, complete, and comminuted.

Although traumatic bowing was described by Rauber in 1876,³⁰⁰ it was not widely recognized until Spencer Borden’s classic paper was published in 1974.⁴⁰ This injury occurs almost exclusively with children’s forearm fractures.¹⁷⁶ Bow fractures (Fig. 10-23)
show no obvious macroscopic fracture line or cortical discontinuity,
but they do demonstrate multiple microfractures (slip lines) along the
length of the bow.²⁷⁹ At times, a
nearly classic buckle fracture (torus fracture) coexists with a bow
fracture. The most common clinical scenario is a plastically deformed
ulna along with a more typical fracture of the radius.¹⁹⁸

Borden⁴⁰ and
subsequent authors stressed the importance of natural remodeling
potential in these injuries but voiced concern about this approach in
older children (especially those over 10 years of age).⁴⁰,¹⁹⁸,²⁷⁹ Vorlat and DeBoeck³⁴⁰
reported incomplete remodeling in 3 of 11 children at long-term
follow-up (average 6.7 years) after traumatic bowing of the forearm.
Because these three children were between the ages of 7 and 10 at the
time of injury, the authors recommended more aggressive efforts at
reduction in all patients with clinically significant deformity (more
than 10 degrees) older than 6 years of age.³⁴⁰ Traumatic bowing that causes cosmetically or functionally unacceptable angular deformity²⁷⁶
must be manipulated under general anesthesia or deep sedation because
strong (20 to 30 kg) gradual force applied over 2 to 3 minutes is
required to obtain acceptable alignment (Fig. 10-24).²⁷⁹
Application of this reductive pressure over a rolled towel, block, or
surgeon’s knee fulcrum followed by a three-point molded cast can
substantially (although at times still incompletely) correct the
deformity. Care must be taken to avoid direct pressure over adjacent
epiphyses for fear of creating a physeal fracture.

Greenstick fractures present special issues in terms of
diagnosis and treatment. Angulated greenstick fractures of the shafts
of the radius and ulna at different levels indicate a significant
rotational component to the injury (see Fig. 10-8).
Evans, Rang, and others have stated that the apex-volar angulation
pattern usually is associated with a supination-type injury mechanism,
while most apex-dorsal greenstick fractures involve a pronation-type
injury mechanism (Fig. 10-25),⁹²,⁹⁴,²³⁰,²⁶² although exceptions certainly occur.⁹²,¹³²
Often, the apparent angular deformity can be corrected by simply
reversing the forearm rotational forces (e.g., reducing an apex-dorsal
pronation-type injury with supination).

Noonan and Price²³⁰
observed that it is difficult to remember whether to use pronation or
supination reductive forces and suggested that most fractures can be
reduced by rotating the palm toward the deformity. They also noted that
most greenstick fractures are supination injuries with apex-volar
angulation and thus can be reduced by a pronation movement.²³⁰

Greenstick fractures that occur near the same level
probably have little to no rotational component and are best corrected
by manipulative reduction and three-point molding techniques (see Fig. 10-9).
Charnley believed that greenstick fractures of the forearm in children
perfectly illustrated his dictum that “A curved plaster is necessary in
order to make a straight limb.”⁶¹ He
also stated that “The unsuspected recurrence of angular deformity in
greenstick fractures of the forearm, while concealed in plaster, is an
annoying event if it takes the surgeon by surprise and is not
discovered until the plaster is removed. Parents, quite understandably,
may be more annoyed about this happening to their children than if it
had happened to themselves, and do not easily forgive the surgeon.”⁶¹
Despite these concerns, it is clear from large published reports that
greenstick fractures can almost always be successfully treated with
nonoperative methods.³⁶⁵

Two philosophies are reflected in the literature
regarding greenstick fracture reduction: one in which the greenstick
fracture is purposely completed and another in which it is not. Those
who favor completing the fracture (dating back at least to the 1859
work of Malgaigne) cite concerns about lost reduction and recurrent
deformity that can be prevented only by converting the greenstick into
a complete fracture.²⁴,³⁶,¹⁰³,¹⁵² Others prefer to maintain and perhaps exploit some of the inherent stability of the greenstick fracture.⁶,⁶³,⁸⁰,⁹²,³²²
In addition to the traditional view that loss of reduction is less
likely if a greenstick fracture is completed, there also is the
theoretical advantage of a lower refracture rate because of more
exuberant callus formation.⁶³,²³⁰ To the best of our knowledge, these theories have not been validated in any controlled clinical studies. Davis and Green⁸⁰
advocated a derotational approach to greenstick fracture reduction and
reported a 10% (16/151) reangulation rate in their series of patients
with greenstick fracture. They compared this to the 25% (12/47)
reangulation rate in patients with complete fractures and questioned
the wisdom of routinely completing greenstick fractures.⁸⁰ In a prospective study, Boyer et al.⁴⁴ showed statistically that greenstick fractures maintain their reduction better than complete forearm fractures.

Complete fractures in different regions of the shaft of
the forearm behave differently from a clinical perspective and have
classically been divided into distal-, middle-, and proximal-third
fractures. Single-bone complete fractures usually are caused by direct
trauma (nightstick fracture) and are difficult to reduce. Blount
described a reduction technique that may be effective for reduction of
a displaced single-bone shaft fracture.³⁴
The intact bone is used as a lever to re-establish length of the
fractured bone, and then transverse forces are applied to realign the
bone ends (see Fig. 10-11). Both-bone complete
fractures (often with bayonet shortening) are common and are best
treated with finger-trap or arm traction applied over 5 to 10 minutes.
This stretches out the soft tissue envelope and aids in both reduction
and cast or splint application. Traction allows complete fractures to
“seek their own level of rotation” and allows correction of rotational
malalignment.⁸⁰

The position of immobilization for forearm fractures has

been an area of debate since the days of Hippocrates.³⁶
Theoretically, the position of forearm rotation in an above-elbow cast
or splint affects rotational alignment of complete fractures at all
levels; however, a study of distal-third forearm fractures found no
significant effect of forearm rotation position on ultimate alignment.⁴⁴
We are aware of no similar studies analyzing the effects of forearm
position on middle- or proximal-third shaft fractures, and treatment is
influenced by certain anatomic considerations. Because of the strong
supination pull of the biceps, aided by the supinator, complete
proximal radial fractures may be best immobilized in supination so that
the distal forearm rotation matches that of the proximal forearm (see Fig. 10-19).
The position of immobilization of fractures in the middle third of the
forearm commonly is dictated by whether the radial fracture occurs
distal or proximal to the insertion of the pronator teres. Fractures
proximal to its insertion are best treated by fully supinating the
distal fragment, while those distal to its insertion are probably best
treated in a neutral position.

Manipulated fractures should be evaluated weekly for the
first 2 to 3 weeks because most position loss can be recognized and
corrected during this time.¹⁷⁹,³⁴¹
Any significant shift in position between visits necessitates cast
wedging or a cast change, with remolding and possible fracture
remanipulation if unacceptable displacement is present. Voto et al.³⁴¹ found that, in general, 7% of forearm fractures redisplace; this can occur up to 24 days after the initial manipulation. Davis⁸⁰
reported a 25% reangulation rate in complete fractures. Remanipulation
can be done in the office following administration of oral analgesics.
Judicious use of benzodiazepines may also be valuable because of their
anxiolytic effects.

Although in adults the above-elbow cast generally is
changed to a below-elbow cast after 3 to 4 weeks, this is unnecessary
in most children because they heal more quickly and permanent elbow
stiffness is rare.¹⁷¹ A cast change
at week 3 or 4 also can be traumatic to a young child and carries the
additional small risk of cast saw injury. Once the fracture shows good
callus formation, the cast can be removed. Because shaft fractures of
the radius and ulna in children have a significant rate of refracture,¹⁵,¹⁸¹,³²⁶ they should be splinted for an additional period of time.⁶⁷ Parents should be warned of the risk of refracture.

Above-elbow casting with the elbow in extension has been
suggested for some complete fractures of the middle and proximal thirds.²⁹³,³⁴⁴,³⁴⁸ The supination moment exerted by the biceps has been shown to be diminished when the elbow is extended.²²⁴ Walker and Rang³⁴⁴
reported successful treatment of 13 middle- or proximal-third forearm
shaft fractures with this method (some following failed flexed-elbow
casting). They suggested that the “short fat forearms” of some young
children prevented successful flexed-elbow casting.³⁴⁴ Shaer et al.²⁹³
also reported 20 children treated with this method and emphasized full
supination of the forearm. Three of their patients required cast
wedging, but at final follow-up 19 of the 20 patients had excellent
results.²⁹³ One patient who was lost to follow-up for 6 months (presumably removing his own cast) did suffer “mild residual deformity.”²⁹³ Walker and Rang³⁴⁴
recommended that benzoin be applied to the skin, in addition to
creation of an adequate supracondylar mold, to further secure the cast.
Casting the thumb in abduction with extra padding may prevent the cast
from sliding. Turco³³⁰ suggested
that reduction should be obtained with horizontal traction applied to
the extended upper extremity, followed by additional steps outlined in Table 10-5. Based on published clinical results, concerns related to cast slippage and elbow stiffness appear to have been overstated.²⁹³,³⁴⁴ The main drawback of this technique is its awkwardness as compared to flexed-elbow casting.³⁴⁴

Although comminuted forearm fractures are less common in children than in adults,³²² they do occur.²⁵,¹⁰³,¹⁰⁴,¹⁵²,¹⁸⁰,³⁵⁸ Comminuted fractures tend to occur in conjunction with high-energy injuries, such as open fractures.¹⁵²,²⁰⁵
Comminuted forearm fractures deserve special attention because they
often require specially tailored treatment approaches. If satisfactory
reduction cannot be achieved or maintained by closed methods, then
other treatment alternatives should be considered.

One option is to accept some shortening; according to Price,²⁵⁵
this may help maintain motion through interosseous membrane slackening.
Shortening of more than 1 cm is unacceptable in either single-bone or
both-bone comminuted patterns. Standard closed fracture treatment
generally is unsuccessful when both bones are comminuted, and surgical
stabilization may be necessary.¹⁰³ Bellemans and Lamoureux²⁵
reported intramedullary nailing of all comminuted forearm fractures in
their pediatric series. Other reported fixation methods for comminuted
forearm fractures in children include plate-and-screw devices,¹⁰³,¹⁰⁴ flexible intramedullary nailing for single-bone comminution,²⁶⁹ and pins-and-plaster techniques.³⁴² Bone grafting is rarely if ever indicated in acute comminuted forearm features in children.

Duncan and Weiner⁸⁹
cited an “aggressive surgical mentality” as the reason for frequent
operative treatment of pediatric forearm fractures, and Wilkins³⁵² expressed concern about “impetuous” surgeons who are too eager to operate. Cheng et al.⁶²
documented a more than 10-fold increase in the rate of operative
treatment of forearm shaft fractures in children, but it is unclear as
to whether this increase in operative treatment has led to a
commensurate improvement in clinical outcomes.

Operative treatment of radial and ulnar shaft fractures
usually is reserved for open fractures, those associated with
compartment syndrome, floating elbow injuries, and fractures that
develop unacceptable displacement during nonoperative management.
Residual angulation after closed treatment is much better tolerated by
younger children than older adolescents and adults because of the
increased remodeling potential in the younger age group.¹⁶⁸
As a consequence, adolescents are more likely to benefit from surgical
treatment of their forearm fractures than are younger children.
Although internal fixation is the standard of care for displaced
forearm fractures in adults, the success of nonoperative methods and
the complications associated with internal fixation have tempered
enthusiasm for its application to pediatric forearm fractures. Compared
to closed treatment methods, healing is slower after open reduction and
internal fixation,²⁵ no matter what type of implant is used.¹⁰³
Crossed Kirschner wire fixation techniques that often are used
successfully in the distal radius are technically difficult in the
shaft region of the radius and ulna. In rare situations, external
fixation has been used for pediatric forearm fixation.²⁹¹

Preoperative planning is essential regardless of which
surgical technique is chosen. Assessment of the fracture, including
rotation and the presence or absence of comminution, is important.
Bone-plate mismatch (due to narrow bones and wide plates) and extensive
soft tissue dissection are risks when adult-sized plates are applied to
pediatric bones.³⁵⁶ Before
intramedullary nailing of fractures, the forearm intramedullary canal
diameter should be measured, especially at the narrowest canal
dimension; typically this is the central portion of the radius³⁰⁵
and the distal portion of the ulna near the junction of its middle and
distal thirds. Precise canal measurement can be difficult,^277,306
and the consequences of a nail or pin that is too large are probably worse than those of a nail or pin that is too small.²³⁴,²⁸⁸ Modern digital radiography systems have made these measurements easier.²⁴²

Open reduction and internal fixation of pediatric
forearm shaft fractures with plates and screws is a well-documented
procedure in both pediatric series²⁴⁰,³¹⁰,³²³,³³³ and adult series that include patients as young as 13⁶⁰ and even 7⁶⁰ years of age. In one of the early series of pediatric forearm fractures fixed with plates,⁸³
dynamic compression plates and one-third tubular plates applied with
standard atlas orthogonal technique (six cortices above and below the
fracture site) obtained good results.²²⁷ Four-cortex fixation on either side of the fracture site has been shown to be equally effective in pediatric forearm fractures.³⁵⁸

Plate fixation uses the standard adult approach and
technique except that smaller plates (2.7-mm compression and stacked
one-third tubular), fewer screws, and single-bone fixation often are
acceptable.³⁵⁸ Plate fixation may
allow more anatomic and stable correction of rotational and angular
abnormalities and restoration of the radial bow than with noncontoured
intramedullary rods; however, the larger incisions and extensive
surgical exposures required for plate fixation have raised concerns
regarding unsightly scars²⁷⁵,³³³,³⁵⁶ and muscle fibrosis with consequent motion loss.³⁵⁸
While the cosmetic concerns seem valid, ultimate forearm motion is
similar with the two techniques, with only minor losses reported in the
literature after both plating and intramedullary nailing.⁷⁴,¹⁶⁸,²⁹⁷,³³² Fernandez et al.⁹⁷
recently documented these precise issues very nicely in that they found
no significant differences in functional outcome in their plate
fixation versus intramedullary nailing patients, but they noted the
longer operating room time and inferior cosmesis of the plated patients.

Open reduction and internal fixation with plates and
screws may be appropriate in the management of fractures with delayed
presentation or fractures that angulate late in the course of cast care,¹³⁵,³⁵⁸
when significant fracture callus makes closed reduction and
percutaneous passage of intramedullary nails difficult or impossible.¹³ Other indications for plate fixation include shaft fractures with significant comminution¹⁰³ and impending or established malunion³²⁹ or nonunion.¹³⁶,¹⁸⁹,²³⁴ Several authors have reported good results with plate fixation of the radius only⁵⁰,¹⁰⁵,²⁴⁰,²⁶² or the ulna only (Fig. 10-26).²⁶ Bhaskar and Roberts²⁶
compared 20 children with both-bone plate fixation to 12 with ulna-only
fixation and found significantly more complications in the dual plating
group, although motion was equal at 1-year follow-up. Single-bone
fixation requires satisfactory reduction of both bones. Flynn and Waters¹⁰⁵
stated that they would preferentially plate the radius only when the
fracture could not be reduced by closed means. Two patients in Bhaskar
and Roberts’²⁶ study required open
reduction and internal fixation of the radius when it was not
adequately reduced after plate fixation of the ulna.

Currently, intramedullary fixation is the preferred method for internal fixation of forearm fractures in children.¹⁰,⁴⁸,¹⁸⁰,¹⁸⁸,¹⁹⁴,²⁵⁹,²⁶⁰,³³⁷
Intramedullary fixation of children’s forearm fractures dates back at
least to Fleischer’s 1975 report in the German literature in which he
called it “marrow wiring.”¹⁰¹ Closed
intramedullary nailing (also known as indirect reduction and internal
fixation) of diaphyseal forearm fractures in adolescents was later
reported in the English language literature by Ligier et al.,¹⁹¹ Amit et al.,¹⁰ and others.³⁰,¹⁸⁴,³⁵⁶
A variety of implants have been used for forearm intramedullary
nailing, including Kirschner wires, Rush rods, and Steinmann pins.
Continued favorable reports from around the world (e.g., England,
Germany, New Zealand, Turkey, and the United States) have established
intramedullary fixation as the surgical treatment of choice.⁵⁶,¹¹⁵,¹⁶²,¹⁸⁸,²⁶⁷

Intramedullary fixation has several advantages over
plate fixation, including improved cosmesis because of smaller
incisions and less deep tissue dissection, potentially leading to a
lower risk of stiffness.⁷⁴,¹⁸⁰,²⁹⁷,³⁵⁶ Contoured pins are used in the radius to preserve its natural anatomic bow¹⁰,⁷⁴,²⁵⁹,²⁶⁷,³⁴⁶; contoured pins are not necessary for the ulna.¹⁰
Although the rotational stability of pediatric forearm fractures
treated with intramedullary fixation has been questioned, Blasier and
Salaman³⁰ suggested that the strong
periosteum in children resists torsional stresses. In a cadaver study
of the rotational stability of fractures of the ulna and radius treated
with Rush rods, Ono et al.²³⁸ found that intramedullary fixation of both bones reduced fracture rotation to one eighth of that in unfixed fractures.

In the early 1980s, Metaizeau et al.²¹⁶ described elastic stable intramedullary nailing (ESIN) of pediatric forearm fractures

with small-diameter (1.5- to 2.5-mm) contoured implants.¹⁹¹ No effort was made to fill the medullary canal as with other intramedullary nailing techniques,²⁶⁹ and the “summit of the curve must be calculated preoperatively to lie at the level of the fracture.”¹⁸⁴
The prebent flexible rods (known as Nancy nails) were reported to
maintain satisfactory fracture alignment while encouraging development
of normal physiologic fracture callus.¹⁹¹,²¹⁶,²⁵¹
Biomechanically, these implants have been shown to act as internal
splints provided the nails extend three or more diameters beyond the
fracture site.¹⁵⁸ Good results with this technique have been reported by numerous authors (Figs. 10-27 and 10-28).¹³¹,²²⁵,²⁶⁹,²⁸⁷,²⁹⁴,³²⁵,³²⁸,³⁵⁷

Because the ESIN technique emphasizes the interdependence of the radius and ulna, if both bones are fractured, both

bones are internally fixed.¹⁸⁴
It also is dependent on anchorage of the nails in the upper and lower
metaphyseal portions of the bone to produce an internal three-point
fixation construct.¹⁸⁴ Technique
principles include fixing first the bone that is easiest to reduce,
using physeal-sparing entry points, and using small nails varying in
diameter from 1.5 to 2.5 mm.¹⁸⁴ A nail that is too large may lead to nail incarceration and distraction at the fracture site, especially in the ulna.²³⁴ Contouring of both nails is recommended, with particular attention to restoration of the appropriate radial bow (Fig. 10-29).
Initially, nails were removed by about the fourth postoperative month,
but several refractures led the originators of the technique to delay
nail removal until 1 full year after surgery.¹⁸⁴ Pin ends should be cut short and buried to maintain prolonged fixation.

Immediate motion has been recommended by some authors after ESIN of pediatric forearm fractures,²⁵,¹³¹,¹⁸⁴,³³⁷ while others have recommended immobilization for variable periods of time.⁴⁸ Early refracture with nails in place has been reported. Bellemans and Lamoureux²⁵
considered displaced oblique or comminuted midshaft forearm fractures
in children older than 7 years of age to be an indication for ESIN.
They considered bayonet apposition (overriding) to be unacceptable at
any age because of concerns about rotational malalignment and frequent
narrowing of the interosseous space.²⁵ Their fixation technique

involved passage of the intramedullary nails followed by rotation of
each nail until the greatest distance between the two bones was
achieved in full supination.²⁵

In one large epidemiologic study, open fractures of the
shafts of the radius and ulna and open tibial shaft fractures occurred
with equal frequency, making them the most common open fractures in
children.⁶² Although the infection
rate is extremely low for open fractures, even grade I open forearm
fractures in children have been associated with serious complications
such as gas gangrene.⁹⁶ Early irrigation and débridement²¹²,³⁰² are indicated for open forearm fractures, and care should be taken to inspect and properly clean the bone ends.¹⁶⁵ Roy and Crawford²⁷⁵ recommended routinely inspecting both of the bone ends for the presence of intramedullary foreign material (Fig. 10-30).
Once débrided, open forearm fractures can be stabilized by any of the
available internal fixation methods without undue risk of infection (Fig. 10-31).¹²⁸,¹³⁵,¹⁹⁵
Open fractures tend to be more unstable than closed fractures (because
of soft tissue stripping and comminution) and more commonly require
internal fixation. Internal fixation also may facilitate soft tissue
management and healing.³⁵⁸ Professor Lim¹⁹² and his co-authors

from the KK Children’s Hospital in Singapore recently reminded us that
internal fixation is not an absolute prerequisite and many children
with such open fractures may still be successfully managed with casting
alone.

The amount of periosteal stripping and possible foreign
body reaction associated with open forearm fractures may produce an
unusual radiographic appearance: the “ruffled border sign” (Fig. 10-32).
Usually, this seems to represent a normal healing response in growing
children, but occasionally it is an early sign of osteomyelitis. The
infection rate ranges from 0% to 33% for open fractures in children.¹²⁸,⁷⁴,¹²⁸,¹³⁵,¹⁷⁹,¹⁹⁵,²³⁰,²⁴⁰,²⁵⁵,³⁵⁸
Even grade I open forearm fractures in children can be complicated by
gas gangrene or osteomyelitis, and therapeutic amputation has been
reported.⁸⁰,⁹⁶,¹⁵²
Open fracture grade does not appear to correlate with the infection
rate in childhood forearm fractures, with most of the serious forearm
infections reported in the literature occurring after grade I fractures.

The most common short-term complication of forearm shaft
fracture treatment is loss of satisfactory reduction in a previously
well-reduced and well-aligned fracture, a complication that occurs in
10%⁵⁸,⁶⁵,⁸⁰,¹⁶¹,³⁴² to 25% of patients.⁵⁸,⁸⁰ Initial follow-up radiographs are a screening test aimed at identifying redisplacement. Kramhoft and Solgaard¹⁷⁹
recommended that children with displaced diaphyseal forearm fractures
have screening radiography at 1 and 2 weeks after reduction. Voto¹⁷¹
also pointed out that most fractures that redisplace do so within the
first 2 weeks after injury. Inability to properly control fracture
alignment with closed methods is the most commonly reported indication
for operative intervention.¹⁸⁸,²⁵⁹,²⁷⁵,²⁹⁷,³⁶⁵

The most common explanations for loss of fracture
reduction are cast related (poor casting technique, no evidence of
three-point molding).⁶³,³⁴² The more experienced the surgeon, the greater the likelihood of successful reduction.⁵⁸ Other factors that have been found to be associated with forearm fracture redisplacement are quality of initial reduction,³⁶² missed follow-up appointments,⁶⁸ proximal-third fractures,⁷² and failure of the doctor to respond to early warning signs such as slight loss of reduction at 1-week follow-up.¹¹³ Strategies for dealing with redisplacement include allowing the deformity to remodel,¹⁴³ cast wedging,¹⁸,¹⁵²,¹⁶⁹ rereduction and recasting,⁸⁰,³⁴² pins and

plaster,³³,⁸⁹,³⁴² indirect reduction and internal fixation,¹⁰ and open reduction and internal fixation.³⁵⁸
Reports in the literature suggest that most forearm shaft fractures
that redisplace can be successfully managed with repeat closed
reduction and casting.⁸⁰,³⁴²

The forearm is a predominantly nonsynovial joint with
highamplitude motion as its main function. The most common long-term
complication of forearm shaft fracture treatment is significant forearm
stiffness,¹⁴³ with pronation loss occurring almost twice as frequently as supination loss.¹⁴⁴ Loss of pronation or supination motion sometimes occurs despite perfectly normalappearing radiographs.¹⁶⁸,²²⁹,²⁵⁵ Abnormal bony alignment of the forearm bones leads to predictable motion deficits.¹⁶⁶ Stiffness that exceeds that expected from bony malalignment alone¹⁶⁶
and stiffness that occurs with normal radiographs are indications of
fibrosis of the interosseous membrane or contracture of the
interosseous ligament.¹⁶⁸,²⁵⁵

With focused testing of forearm motion, between 18%⁵² and 72%¹⁴⁴
of patients show at least some minor deficits after nonsurgical
treatment. Most minor deficits are not even noticed by patients and
rarely are associated with functional limitations.⁵²,⁷⁶,²²⁹ More severe losses of forearm rotation have far greater impact.²¹⁹ In their series of malunited forearm fractures (thus strongly weighted to demonstrate forearm stiffness), Price et al.²⁵⁵
reported a 15% (6/39) rate of mild stiffness (up to 25-degree loss) and
an 8% (3/39) rate of severe forearm stiffness (loss of 45 degrees or
more of either pronation or supination). Holdsworth’s¹⁴⁴ series of malunited pediatric forearm fractures had a similar rate (6%) of severe forearm stiffness. Holdsworth¹⁴⁴
told the classic story of a female whose inability to properly pronate
caused her to elbow her neighbors when eating at the table. Patrick²⁴³
pointed out that it is possible to compensate for pronation losses with
shoulder abduction, but no similar compensation mechanism exists for
supination losses. Such severe motion loss is a very undesirable
outcome. For surgical treatment of these injuries to be a rational
choice, the rates of stiffness after surgery must be lower than those
after cast treatment.¹³⁰

Bhaskar and Roberts²⁶
published one of the only studies of plated pediatric forearm fractures
to report goniometric pronation and supination data. Both their
single-bone (ulna) and both-bone plated patients showed mild forearm
motion losses (maximal 18% loss of pronation).²⁶ Variable rates of mild forearm range-of-motion losses have been reported after intramedullary fixation. Amit et al.¹⁰
reported a 40% rate of mild stiffness (5 to 10 degrees) in 20 pediatric
patients after Rush rod fixation of forearm fractures. Combined data
from five series of the flexible intramedullary nailing (Kirschner
wires, Steinmann pins, Nancy nails) reveal a 1.6% rate (2/128) of mild
forearm stiffness (up to a 20-degree loss) and a 0% (0/128) rate of
severe motion loss (40 degrees or more loss of either pronation or
supination).¹⁰,²⁵,⁹⁸¹⁸⁰,²⁹⁷,³⁶⁵
No published series of nonoperatively treated forearm shaft fracture
patients has exceeded these results relative to preservation of forearm
motion.

Refracture occurs more often after forearm shaft fractures in children than after any other fracture.¹⁸¹ Tredwell³²⁶
found that forearm refractures occurred at an average of 6 months after
original injury and were more common in males (3:1) and in older
children (approximately 12 years old). Refracture rates of 4%⁹⁸ to 8%¹⁹³ have been reported in pediatric diaphyseal forearm fractures. Bould and Bannister⁴³
reported that diaphyseal forearm fractures were eight times more likely
to refracture than metaphyseal fractures. Schwarz et al.²⁹²
found that 84% (21/28) of the forearm refractures in their series had
initially presented as greenstick fractures. Based on the stage of bony
healing, refractures may occur through the original fracture site,
through both the original site and partially through intact bone or
completely through intact bone,³⁵⁰ but most seem to occur through the original fracture site.

Several authors have suggested that internal fixation is necessary after refracture,¹⁵,²⁵²,²⁶⁹ but Schwarz et al.²⁹² reported good results with repeat closed reduction and casting in 14 of

17 patients with refractures. Closed reduction also has been shown to
be effective for forearm refractures that occur with flexible nails in
place (Fig. 10-36).²²²
The best treatment of refracture is prevention, and patients should be
splint-protected (removable forearm splint or thermoplastic gauntlet)
for a period of 2 months depending on activity after initial bone
healing.²³⁰,²⁵⁵
Refracture is rare during splint wear. Parents must be cautioned about
the risk of refracture despite apparently adequate bone healing on
radiographs.

Refracture after plate removal has been discussed frequently in the literature¹⁰³,²²⁷,²⁵⁴,³³² and appears to be associated with decreased bone density beneath the plate.¹⁷⁴ This has led many authors to question the routine use of plate fixation for pediatric forearm fractures.³⁰,⁶⁸,²⁵⁴,³³³ Refractures also have been reported after removal of intramedullary forearm fixation in children.⁷⁴,¹³⁵,¹⁶⁸,¹⁸⁴,²⁹⁷,³²⁸,³⁶⁴
The main strategies aimed at decreasing the risk of refractures after
implant removal are documentation of adequate bony healing before
implant removal, and an additional period of splint protection after
implant removal until the holes have filled in.

Evaluation of pediatric forearm fracture malunion must take into account established malreduction limits and expected pediatric

remodeling potential. Thus, a malunion of 30 degrees may become less
than 10 degrees during the course of follow-up. The level of the
malunited fracture also must be considered, because the consequences of
malreduction vary according to level.²⁸⁰,³⁶¹
More deformity in the predominant plane of motion is acceptable in
fractures near physes of long bones than in diaphyseal fractures.
Normal motion can be preserved despite persistent radiographic
abnormality (Fig. 10-37).

Malunion of radial and ulnar shaft fractures can lead to
cosmetic deformity and loss of motion; however, significant loss of
function occurs in only a small percentage of patients.⁵²,⁷⁶,²²⁹ Some authors have recommended more aggressive efforts at correction of forearm fracture malunions.²¹⁴,²⁵³
Early malunions (up to 4 or 5 weeks after injury) can be treated with
closed osteoclasis under anesthesia. If closed osteoclasis fails to
adequately mobilize the fracture, a minimally invasive drill
osteoclasis can be done.²⁹ A small-diameter drill (or Kirschner wire) is used to make multiple holes in the region of the malunion

before forcefully manipulating the bone back into alignment.²⁹ Internal fixation is rarely, if ever, needed.

Once significant callus is present, indirect reduction
and internal fixation with flexible intramedullary nails can be
difficult or impossible because the fracture site is now blocked with
callus. Thus, established or impending malunions that cannot be
adequately controlled with a cast may require formal open reduction and
plate fixation (Figs. 10-38 and 10-39).
Many fractures that heal with angulation or rotation of more than the
established criteria regain full motion and have an excellent cosmetic
outcome. Fractures may require corrective osteotomy if they fail to
remodel after an adequate period of observation or if adequate motion
fails to return.²¹⁴,³²⁹ Such corrective osteotomies have been done long after injury (up to 27 years) and additional motion has still been regained.³²⁹ There is a minor subset of malunions that

do not remodel, that have functional limits (especially when there is
limited supination deformity), and therefore, are candidates for
osteotomy.

The diagnosis of delayed union is based on documentation of slower-than-normal progression toward union.¹⁸⁹ Daruwalla⁷⁶
stated that normal healing of closed pediatric forearm shaft fractures
occurs at an average of 5.5 weeks (range 2 to 8 weeks). Delayed union
can be practically defined as a failure to demonstrate complete healing
(four cortices) on sequential radiographs by 12 weeks after injury,
which exceeds the upper limit of normal healing by about 1 month.
Nonunion can be defined as absence of complete bony union by 6 months
after injury, which exceeds the upper limit of normal healing by about
4 months.

Delayed unions and nonunions are rare after closed forearm shaft fractures in children.⁹⁹,¹⁸⁹,³⁰⁷
In six large series of pediatric diaphyseal forearm fractures treated
by closed methods, a less than 0.5% rate (1/263) of delayed union and
no nonunions were reported.²⁵⁵,¹⁴⁴,⁷⁶,⁵²,¹⁶⁸,¹⁷⁹
Delayed unions and nonunions are more common after open reduction and
internal fixation and open fractures. Particular concern has been
raised about the potential of antegrade ulnar nailing (olecranon
starting point) to distract the fracture site.²³⁴ Combined data from four series of plated pediatric forearm fractures indicated a 3% (3/89) nonunion rate²⁶,²²⁷,³³³,³⁵⁸; 24% (21/89) of these were open fractures and at least one³⁵⁸ of the three nonunions occurred after a grade III open fracture.²²⁷,³³³
Large series of open pediatric forearm fractures (treated by a variety
of internal fixation methods) reported comparable numbers: 5% (8/173)
delayed union rate and 1% (2/173) nonunion rate.⁷⁹,¹²⁸,¹³⁵ In a series of 30 nonunions in children, only 6 were in the forearm, and half of these were after open fractures.¹⁸⁹

Because of the overall rarity of nonunions in children,
the possibility of unusual diagnoses such as neurofibromatosis must be
considered.⁶⁹,⁷¹,¹⁵⁵,²⁰²
After open injury or surgical intervention for other reasons, the
possibility of septic nonunion must be ruled out. In the absence of
such extraneous factors, nonunion of pediatric forearm fractures seems
to be related to surgical treatment.⁶⁹,⁷¹,¹⁵⁵,²⁰²,³⁰⁷ Weber and Cech³⁴⁹
divided nonunions into atrophic and hypertrophic types. Atrophic
nonunions probably are best treated with bone grafting and compression
plating. Compression plating or other stable internal fixation without
grafting usually is sufficient for hypertrophic nonunions.¹⁸⁶

Posttraumatic radioulnar synostosis results in complete
loss of forearm rotation. Most cross-unions that form after pediatric
forearm shaft fractures are type II lesions (diaphyseal crossunions),
as described by Vince and Miller (Fig. 10-40).³³⁸ Although some series of adult forearm fractures reported synostosis rates of 6% to 9%,²²,³¹⁶ posttraumatic radioulnar synostosis is a rare complication of pediatric forearm shaft fractures.³³⁸ In children, it usually is associated with high-energy injuries,³³⁸ radial neck fractures,²⁷⁴ and surgically treated forearm fractures.⁷⁴,²³⁵ Some have suggested a familial predisposition to this complication.¹⁹⁹ Postoperative synostosis after forearm fractures in children is almost exclusively associated with plate fixation.³⁵⁴,³⁵⁸
The risk of cross-union is increased when open reduction and internal
fixation of both-bone fractures are done through one incision.²²,⁶⁸

Both osseous and nonosseous cross-unions may form in the forearm,¹¹,⁶⁵,³⁴³
but the more common type is osseous. After a synostosis matures (6 to
12 months), it can be excised along with any soft tissue interposition.²³¹,³³⁸ The results of synostosis resection may be better in adults than children,³³⁸ perhaps because

of the more biologically active periosteum in children.⁸⁵,³³⁸
Interposition of inert material (such as Gore-tex [W. L. Gore &
Associates, Inc., Elkton, MD] or bone wax) has been used to decrease
the chances of recurrent synostosis.¹¹,²⁰,²³⁵,³³⁸
Nonsteroidal anti-inflammatory drugs and radiation treatment have been
reported after synostosis excision in adults, but their use in children
remains undefined. An alternative treatment is corrective osteotomy if
the patient is synostosed in a position of either extreme pronation or
supination. If the patient is stuck in a neutral position after
posttraumatic synostosis, surgical intervention is usually not
recommended.

Infection occurs only in surgically treated forearm
shaft fractures and open fractures. Appropriately timed preoperative
antibiotic prophylaxis is believed to diminish the risk of infection.
Children with open forearm fractures are considered to be at high risk
for infection, and early (usually less than 24 hours)³⁰² irrigation and débridement in the operating room is indicated.²⁷⁵
Whether in the backyard, the barnyard, the football field, or the hay
field, open forearm fractures that occur in organic settings are best
treated with early irrigation and débridement with inspection of the
intramedullary canal of both bone ends, where soil contamination tends
to occur during injury (see Fig. 10-30). Soil
contamination has been reported to lead to gas gangrene and subsequent
upper extremity amputation in children with grade I open forearm
fractures.⁹⁶ Emergency room
irrigation and débridement is not recommended and is considered
inadequate with increased risk of serious infection.

In four published series of plated pediatric forearm
fractures (25% open fractures), deep infection (osteomyelitis) occurred
in 5% (4/83).²¹⁹,²²⁷,³³³,³⁵⁸
Such deep infections usually require extensive additional surgical
treatment to eradicate them. Combined data from 12 series of similar
pediatric forearm fractures (15% open fractures) treated with
intramedullary Kirschner wires, Steinmann pins, or Rush rods revealed a
deep infection rate of 0.46% (2/437)¹⁰,⁴⁸,⁷⁴,¹⁸⁰,¹⁹⁴,²⁵⁹,²⁶⁰,²⁹⁷,³⁴⁶,³⁶⁵
and a superficial infection rate of 2.5% (11/437). Six studies of ESIN
fixation reported a 0.2% (1/370) deep infection rate and a 3% (12/370)
superficial infection rate.⁴⁸,¹³¹,¹⁸⁴,²⁰¹,²⁶⁹,³³⁷ Superficial infections may require oral antibiotics, pin removal, or both.

Open forearm fractures clearly are at increased risk for
infection. Most (96%) open forearm fractures in children are Gustilo
and Anderson¹³⁴ grade I or II.¹²⁸,¹³⁵,¹⁹⁵
Two studies specifically investigated the relationship between the time
from injury until irrigation and débridement and the risk of later
infection. Luhmann et al.¹⁹⁵
reported on 65 fractures (52 type I, 12 type II, 1 type III) that were
irrigated and débrided an average of 5.6 hours (range 1.5 to 24 hours)
after injury, and Greenbaum et al.¹²⁸
reported 62 fractures (58 type I, 4 type II) that were irrigated and
débrided an average of 14.6 hours (range 1.7 to 37.8 hours) after
injury. No statistically significant association was found in either of
these studies; however, most (87%) of these fractures were grade I
injuries. Pooled data revealed an overall 1.2% rate (2/173) of deep
infection and a 0.6% rate (1/173) of superficial infection after
current open fracture treatment protocols.¹²⁸,¹³⁵,¹⁹⁵

The median nerve is the most commonly injured nerve with forearm shaft fractures (whether closed or open injuries),⁸⁰,¹²⁸,¹³⁵,¹⁹⁵ but any peripheral nerve and at times multiple nerves may be involved.⁷⁴ Most of these injuries are simple neurapraxias that occur at the time of injury and resolve spontaneously over weeks to months.⁸⁰,¹³⁴,²²⁸ Actual nerve entrapment within or perforation by the bony fragments has been reported,⁴,¹¹¹,¹¹⁷,¹¹⁸,¹⁵¹,²⁵⁷,²⁵⁸,³¹² most often with greenstick fractures.¹¹⁸,¹⁵¹,²⁵⁷,²⁵⁸ Constricting fracture callus and fibrous tissue also have been known to cause nerve palsies.²⁵⁸,³¹² In patients who fail to recover normal nerve function within a satisfactory time period,⁴
nerve exploration, decompression, and possible nerve repair should be
considered. If signs of progressive nerve recovery (e.g., advancing
Tinel sign, return of function) are not present by the end of the third
month after injury, further diagnostic work-up (electromyography with
nerve conduction studies) is indicated. Prolonged waiting can be
harmful to long term outcome.

Nerve injury after internal fixation is always a
concern. Operative treatment of pediatric forearm fractures by either
indirect reduction and internal fixation techniques or classic open
reduction and internal fixation techniques requires fracture
manipulation and soft tissue retraction, which have the potential to
worsen existing subclinical nerve injury or to create a new injury.
Such injuries are rare and may be underreported. Nerve injury after
pediatric forearm plate fixation has been alluded to but not discussed
extensively.¹⁸⁰ Luhmann et al.¹⁹⁴
reported an 8% (2/25) iatrogenic nerve injury rate after fixation with
intramedullary Kirschner wires or Rush rods: Both were ulnar nerve
injuries that resolved in 2 to 3 weeks. Cullen et al.⁷⁴
reported one ulnar nerve injury that took 3 months to resolve in a
group of 20 patients treated with Kirschner wires or Rush rods.

Certain sensory nerves also are at risk for iatrogenic
damage during surgical forearm fracture treatment, especially the
superficial branch of the radial nerve.⁴⁸,¹⁹⁴,³¹⁴
Pooled data from six series that included 370 ESIN procedures revealed
a 2% (7/370) rate of injury to the superficial branch of the radial
nerve.⁴⁸,¹³¹,¹⁸⁴,²⁰¹,²⁶⁹,³³⁷
The branching pattern of this sensory nerve is complex, and efforts
must be taken to protect it during insertion of intramedullary nails
through distal radial entry points.¹,¹⁶

Severely displaced forearm fractures may trap portions of muscle between the fracture fragments.¹⁴⁶,²⁵⁹
Often, interposed tissue can be effectively removed during standard
fracture reduction, but the muscle may become an obstacle to successful
closed reduction. Much of the volar aspects of the shafts of the radius
and ulna are covered by the flexor pollicis longus and flexor digitorum
profundus, respectively. Many displaced forearm shaft fractures also
have apex volar angulation.²³⁰ As a result, portions of these muscles (or their tendons) are particularly prone to fracture site incarceration (Fig. 10-41).
The pronator quadratus also is vulnerable to fracture site entrapment
in the distal third of the radius and ulna, and it can block reduction
of distal-third forearm fractures.¹⁴⁶

Flexor digitorum profundus entrapment within ulnar¹³⁹,¹⁷⁷,²⁶⁶,²⁹⁵ and radial³⁴⁷
shaft fractures has been reported. Entrapment of the flexor digitorum
profundus typically causes an inability to fully extend the involved
finger (usually index, long, or ring fingers alone or in combination).¹³⁹,²⁹⁵ Even if identified early, this complication rarely responds to occupational or physical

therapy. Surgical intervention is the preferred treatment and requires
only a small incision (usually over the ulna) through which the
adherent tissue is elevated with a blunt instrument from the bone at
the site of the fracture. Excellent restoration of finger motion can be
achieved, even when the release is done up to 2 years after the
fracture.²⁶⁶

Extensor tendon injury has been reported after intramedullary nailing of pediatric forearm shaft fractures.¹³¹,¹⁸⁴,²⁴⁸,²⁵⁹
Primary tendon disruption may be caused by direct trauma during either
nail insertion or extraction. Delayed tendon disruption may be caused
by slow erosion of the tendon as it glides past a sharp nail edge. The
possibility of this complication can be minimized by using surgical
incisions large enough to allow insertion of small blunt retractors to
protect adjacent tendons during nail insertion and extraction.
Avoidance of tendon erosion requires pin lengths that extend beyond the
tendon level into either the subcutaneous tissues⁷⁴,²⁹⁷ or through the skin (external pins).²⁵⁹
Conceivably, the pins could be buried completely within the bone, but
this would require either accepting them as permanent implants
(something not commonly practiced at this time) or significantly
increasing the level of difficulty of nail removal. The extensor
pollicis longus is more at risk near Lister’s tubercle and may require
a late tendon reconstruction with extensor indicis proprius transfer.

Compartment syndrome is rare after closed forearm fractures in children, but its consequences can be devastating. Yuan et al.³⁶³ found no compartment syndromes in 205 closed forearm injuries, and Jones and Weiner¹⁶¹
reported no compartment syndromes in their series of 730 closed forearm
injuries. A single compartment syndrome that developed during cast
treatment of a 12-year-old female with a closed both-bone forearm
fracture was reported by Cullen et al.⁷⁴ Because the diagnosis of compartment syndrome can be difficult in children,²⁶⁵ the index of suspicion must be high.

Compartment syndrome should be suspected in any child
who is not reasonably comfortable 3 to 4 hours after adequate reduction
and immobilization of a forearm fracture.⁶⁶ The risk of compartment syndrome is higher with open fractures¹³⁵,³⁶³ and fractures that are difficult to reduce and require extended operative efforts.³⁶³ Yuan et al.³⁶³
voiced concern that the 10% (3/30) rate of compartment syndrome in
their patients with closed fractures might be due to multiple passes or
“misses” with intramedullary devices during efforts at indirect
reduction and internal fixation. Compartment syndrome was reported by
Haasbeek and Cole¹³⁵ in 5 (11%) of
46 open forearm fractures in their series. The so-called floating elbow
injury has been associated with a rate of compartment syndrome as high
as 33%.³⁶³ Forearm compartment
syndrome is best treated with fasciotomy, releasing both the
superficial and deep volar compartments and the mobile wad. Both the
lacertus fibrosis and the carpal tunnel should be released as part of
the procedure.

Complex regional pain syndromes such as reflex
sympathetic dystrophy are uncommon complications after pediatric
forearm shaft fractures.³³³ Paradoxically, relatively minor injuries seem to place patients at greatest risk.³¹⁵,³⁵¹
The most reliable sign in children is true allodynia: significant
reproducible pain with light touch on the skin. Swelling and other
vasomotor changes often are accompanying signs.¹⁸⁷ The diagnosis in children is

made based almost exclusively on the history and physical examination, with little reliance on studies such as bone scans.³¹⁵ These pain syndromes are best treated initially with physical therapy aimed at range of motion and desensitization.³¹⁵,³⁵¹ Failure to respond to physical therapy may warrant a referral to a qualified pediatric pain specialist.¹⁷²,¹⁸⁷

Over the past 3 decades, the rate of forearm fractures
has increased dramatically in the United States: 33% higher for males
and 56% higher for females.¹⁷⁵
Certain risk-taking behaviors demonstrated by children, as well as
increased use of motorized vehicles like all-terrain vehicles, may be
at least partly to blame.⁴⁷,¹⁹⁷ Increased general physical activity patterns and decreased calcium intake also have been suggested as explanations,¹⁷⁵
but gaps persist in our epidemiologic understanding. Preventing these
injuries remains an admirable but elusive goal. Two main avenues of
research have been explored: optimizing safety during activities known
to be associated with forearm fractures, and investigating biologic
mechanisms related to fracture risk.

The relationship between in-line skating (rollerblading) and pediatric forearm fractures has been shown,²¹⁸,²⁴⁹ with 1 in 8 children sustaining a fracture on his or her first skating attempt.²¹⁸ Prevention efforts have focused largely on protective gear. Wrist guards have been shown to decrease distal forearm bone strain³¹¹ and injury rates.²⁸² Similar protective effects of wrist guards in snowboarders have been shown.²³⁷ Trampolines are another target of injury prevention efforts aimed at a specific play activity.⁹¹ Dramatic increases in trampoline-related injuries were reported during the 1990s, with rates doubling³⁰⁵ or even tripling.¹⁰⁸ Safety recommendations have ranged from constant adult supervision and one-child-at-a-time use¹⁸³ to outright bans on public trampoline use.¹⁰⁸,³⁰⁵

A variety of biologic risk factors have been studied
relative to forearm fractures. Children who avoid drinking milk have
been shown to have increased fracture risk,¹²⁵ as well as those who prefer to drink fruit juice and soda.²⁴⁵ Several studies have shown an increased risk of fractures in females aged 3 to 15 years with low bone density.¹²²,¹²⁴
Diet, nutrition, and exercise are being explored as causative factors,
but the precise reason for the low bone density has not been confirmed.
Too little physical activity (as measured by television, computer, and
video viewing) has been associated with increased fracture risk,
presumably because of decreased bone mineral density.¹⁹⁶
Caution also must be exercised when obtaining dual-energy x-ray
absorptiometry data in children, as up to 88% of scans may be
misinterpreted.¹¹⁰ Childhood obesity is a growing problem in our society.¹¹⁴,¹⁵³
Increased body weight and decreased cross-sectional dimensions of the
forearm bones also have been found in females who fracture their
forearms.³⁰³ Other researchers have found an increased risk of forearm fracture in obese children.¹²³,¹⁶⁰

Parental presence is becoming increasingly popular for
pediatric emergency department procedures. Several studies on chest
tubes, intravenous cannulation, lumbar puncture, and urethral
catheterization have shown increased parental satisfaction when parents
are allowed to stay for these procedures.²¹,¹³⁷,²⁵⁰
Parental presence during induction of anesthesia also has been shown to
have favorable effects on children older than 4 years of age.¹⁶⁴
To the best of our knowledge, there are no published studies on
parental presence during orthopaedic procedures performed in the
emergency department setting. There also are no parental presence
studies on any emergency department procedures performed on children
who are under sedation, when the child is probably not aware of the
parent’s presence.

Certain relationships between perceived procedural
invasiveness and parental presence have been borne out in the
literature. Four hundred parents from the Indiana area were surveyed,
and with increasing invasiveness, the parents’ desire to be present
decreased.³⁸ A survey of academic
emergency medicine attendings, residents, and nurses from across the
country also showed that there is an inverse relationship between
increasing invasiveness and support for parental presence.²³
Boudreaux et al. published their critical review of the parental
presence literature and concluded that “randomized controlled trials
are mixed regarding whether family presence actually helps the patient.”⁴²

Extrapolation of information from the previously
mentioned studies to pediatric orthopaedic settings should be done with
caution. We typically allow parents to be present for the induction of
sedation, and once the patient is sedated the parents are asked to wait
in a designated area. If parents are allowed to be present, we strongly
recommend a dedicated employee to attend to the parent or parents (a
“spotter”). Several parents (typically fathers) have fainted during
such orthopaedic procedures and injured themselves. Parents who stay
for a reduction also should be counseled that the patient may moan or
cry during reduction but will not remember it. Parents who are not
present during reduction should be asked to wait far enough away from
the procedure room so they cannot hear the child.