Tibial Shaft Fractures: Intramedullary Nailing

General anesthesia is preferred for tibial nailing. If a
spinal is used, it should be very short-acting because evaluation of
the neurologic status and pain level is very important after surgery. A
continuous epidural should be avoided in the treatment of tibial
fractures: Although it may provide pain relief for the patient, it
makes clinical compartment monitoring difficult.

A tourniquet is placed on the thigh but rarely inflated.
The entire limb is prepped and draped. If the fracture is open, the
traumatic wounds are irrigated and débrided. The traumatic wound is
commonly extended to improve exposure and visualization. All nonviable
cortical fragments are removed as are foreign bodies or necrotic
tissue. The debridement must be orderly, sequential, and complete to
render the wound surgically sterile in preparation for the nailing. The
fracture ends are carefully inspected and cleaned to ensure that the
proximal and distal intramedullary canal is free from debris. If the
degree of contamination is high and the wound cannot be reliably
rendered clean and sterile, external fixation may be preferable to
nailing. The traumatic wound is irrigated, via pulsed lavage, with 9 to
12 L of normal saline.

After the irrigation and debridement, the surgeon’s
attention is turned to skeletal stabilization. All instruments used for
the washout are removed from the field. The surgeon, assistants, and
nurse change into clean gowns and gloves. Then clean, dry, sterile
drapes are applied to the patient.

Tibial reduction and nailing can be achieved through the
surgeon’s use of a fracture table, a sterile bolster or triangle under
the knee, or a distractor. A sterile radiolucent triangle under the
knee is the simplest technique and is particularly useful in the
treatment of open fractures that require debridement and re-prep before
nailing (Figs. 29.8 and 29.9).

The knee is flexed over the triangle, which permits access to the proximal tibia as well as visualization of the starting point.

The triangle method presents difficulty for obtaining
and maintaining fracture length as well as for controlling angulation
and rotation. The assistant also will have difficulty holding the leg
perfectly still during distal interlocking. This technique works best
with stable fracture patterns.

A fracture table is more complex to set up but is
effective in maintaining leg length and rotation during the procedure.
It is particularly helpful in nonteaching hospitals where a scrubbed
assistant may not be available. With the fracture table, the knee is
flexed 90 degrees over a post, which is placed proximal to the
popliteal fossa to prevent compression of the vessels or peroneal nerve
(Fig. 29.10). Tape is placed around the leg to
prevent external rotation of the extremity. A fracture table works best
in treating patients with isolated closed injuries of the tibia and is
more difficult to use for patients with multiple trauma or open
fractures.

A distractor can be used with a pin placed proximally in
the posterior tibia and distally just above the ankle joint. In acute
fractures, a unilateral frame is usually adequate. After 10 to 14 days,
length is more difficult to restore, and a unilateral frame may lead to
angulation. Therefore, through-and-through proximal and distal tibial
pins are used with a bilateral frame in conjunction with simultaneous
medial and lateral distraction. Compared with a bolster or triangle,
this method takes longer and is more complex, but it provides good
alignment and stability during nailing and interlocking.

The joint is palpated and marked on the knee. The incision starts at the joint line and extends proximally (Fig. 29.11).
The incision need not go distally down to the tibial tubercle. For
fractures of the midshaft or below, the incision and starting point is
just medial to the patellar tendon. The joint is palpated, and the awl
is inserted where the anterior tibia reaches the joint (Fig. 29.12).
The surgeon must stay in the extra-articular area because back out of
the nail may impinge on the femoral condyle. He/she must not enter
distally at the tibial tubercle, as this leads to a more oblique
anterior-to-posterior starting angle, which causes greater risk of nail
penetration into the posterior cortex. In proximal third fractures, the
incision and starting point is just lateral to the patellar tendon (Figs. 29.13 and 29.14).
A sharp, curved, tibial awl is used, and its position is checked in
both the AP and lateral planes with an image intensifier before portal
placement. On the lateral radiograph, the point of the awl should be on
top of the bone (Fig. 29.15). On the AP view, it should be in line with the long axis of the tibia (Fig. 29.16).
When treating proximal fractures, the surgeon may find that staying
more lateral helps prevent both translation and angulation. The Synthes
(Synthes, Paoli, PA) unreamed nail has been a particular problem in
proximal tibial

fractures because of its long and distal curve, which can lead to both translation and angulation of the fracture site (Fig. 29.17).
In proximal fractures, temporary stabilization with a clamp or small
plate is sometimes necessary. To prevent angulation or translation,
blocking screws are another option in proximal fracture treatment.

A bulb-tip guide wire is inserted down the canal. A
small bend in the guide wire made 2 cm from the tip can be helpful
because it can facilitate passage of the wire across the fracture site.
A T handle, which is used to control the bulb-tip guide, is placed in
the midportion of the guide. The bulb tip is initially aimed
posteriorly, and after it has entered the tibia, it is immediately
turned anteriorly and passed down to the fracture site; the surgeon
must avoid penetration of the posterior cortex proximally and exiting
through the fracture site posteriorly. The guide wire is advanced to
the fracture site, and under bi-planar image intensification, is passed
into the distal fragment (Fig. 29.18). It is impacted into the subchondral bone above the ankle to stabilize the bulb tip and to aid in determining length (Fig. 29.19).
A second bulb tip, of identical length to the first, is placed at the
joint line, and a long ruler is used to determine nail length. In
another method of determining nail length, the tibia is measured
externally with a long ruler, hatch marks are made, and the
measurements are confirmed with an image intensifier. Many
manufacturers provide a cannulated depth guide that allows a direct
measurement of nail length.

Based on the preoperative plan and the personality of
the fracture, the surgeon determines whether to use a reamed or
nonreamed technique. If reaming is selected, it must be done properly
so that complications are avoided (Figs. 29.20 and 29.21).
Because the risk of heat necrosis increases during reaming, it should
be carried out at a low torque with sharp reamers that dissipate heat
and pressure (Fig. 29.22). A tourniquet should
be avoided. To prevent soft-tissue damage around the incision, a skin
protector should be used. The surgeon should start with a
small-diameter reamer and increase in one-half millimeter increments
until cortical contact is reached. For closed fractures, reaming one
additional millimeter is usually sufficient. The fracture must be
reduced as the reamer passes (aided by the bulb-tip guide).

If the canal diameter permits, placement of a nail of 10
mm or greater diameter is mechanically beneficial. Excessive reaming
should not be done to achieve this, particularly in open fractures. If
necessary, an 8- or 9-mm nail may be used. However, with smaller nails,
the patient’s postoperative management must be modified. The patient
should be kept from weight bearing until healing is evident, and if
healing is slow, the surgeon should consider dynamization or nail
exchange.

Several investigators have suggested that reaming may
increase the possibility of a compartment syndrome. At the conclusion
of nailing, the compartments should be palpated, and if any concern
exists, the compartment pressure can be measured.

Before nail insertion, a plastic exchange tube is passed over the bulb tip and across the fracture site (Figs. 29.23 and 29.24).
Once the bulb tip is removed, a nail-driving guide without bulb tip is
inserted, and the plastic tube is removed. The nail is driven over this
guide wire. Because the reduction can be maintained with this guide,
cannulated nails should be used. Rarely does the fracture site need to
be opened to pass the nail. Solid nails offer no mechanical advantage
nor do they decrease the risk of infection more than do cannulated
nails. Furthermore, in our experience, solid nails make the passage of
the nail less predictable and the removal of a broken nail extremely
difficult.

The nail is inserted over the guide wire with the
surgeon pushing posteriorly on the proximal end of the nail to minimize
penetration of the posterior cortex (Fig. 29.25). A lateral

image should be used while driving the nail in the upper third of the
tibia. As the nail approaches the fracture site, the fracture must be
aligned in two planes (Fig. 29.26).
The nail must be inserted in slight external rotation. If the nail is
allowed to rotate internally, interlocking will take place on the
posteromedial cortex proximally and distally, which is much more
difficult to complete than is interlocking carried out on the flat
surface of the tibia. Therefore, to make targeting an easier process,
the nail should be externally rotated approximately 10 degrees in
relation to the long axis of the tibia.

As the nail crosses the fracture site, the surgeon must
avoid distraction. Overreaming by 1 mm is helpful. In stable fracture
patterns, traction should be released when the tip of the nail is 1 cm
past the fracture. This should then allow impaction and avoid
distraction. To prevent distraction, the surgeon may need to apply
distal counterpressure as the nail crosses the fracture. Because tibial
nails are small and the screw diameters are similarly small, the
application of a distal screw with the back-slap technique carries a
risk of early fatigue of the distal locking screws. As the nail is
driven down the tibia, the surgeon should reassess the accuracy of its
length. The tibia should be inspected proximally and distally. If the
nail is too short or too long, then it should be removed and replaced
with another nail. In distal fractures, the nail should reach the
subchondral bone. The nail should not be countersunk into the proximal
tibia for greater than 2 to 3 mm or later extraction will be difficult.
Several manufacturers have nail extenders, which can be beneficial for
making small adjustments in length.

Targeting devices that attach to the intramedullary nail are very successful in placing the proximal-tibial locking screws (Fig. 29.27).
Use of anterior-to-posterior screws introduce a slight risk of injury
to vascular structures and should be avoided if possible (Fig. 29.28).
Oblique screws for proximal fractures are safer. Only one proximal
screw is necessary for fractures in the midshaft and below (Fig. 29.29).
For proximal fractures, two or three screws are necessary in the
proximal end of the nail. Blocking screws can also be helpful to
control angulation or translation. For stable transverse or short,
oblique, tibial fractures, the use of the dynamic slot at the proximal
end of the nail allows for impaction of the fracture. If comminution or
a spiral component is found in conjunction with the fracture, the nail
should be statically locked.

We prefer the freehand technique of distal screw
insertion because none of the external guides is consistently helpful.
For length-stable fractures in the middle to the proximal half of the
tibia, only a single distal screw is necessary, whereas in distal
fractures, two or three screws should be used with or without blocking
screws. A medial-to-lateral screw and an anterior-to-posterior screw
can be used, but if using the latter, the surgeon must pay close
attention to both the anterior tibial tendon and posterior vascular
structures.

The nail should be externally rotated 10 degrees to
allow targeting on a flat surface. Via the freehand technique, the
first step is targeting of the skin incision. The image intensifier is
lined up with the nail and tilted and rotated until a perfectly round
hole is visualized. An image intensifier that can magnify the hole
twice its normal size is the best choice. Also, the C-arm head should
be moved away from the tibia to increase the working space and aid in
magnification of the hole. The sharp point of the trocar-tipped pin is
placed on the skin until it is centered in the hole (Fig. 29.30).
A 1-cm stab wound is made directly over the hole on the medial aspect
of the tibia. Because the saphenous vein is very close to the targeted
area, laceration is possible. The sharp point guide is again placed on
the bone until it is centered in the hole (Fig. 29.31). It is brought into the longitudinal axis and checked with fluoroscopy to ensure that it is centered in all planes (Fig. 29.32); a halo should be evident around the guide (Fig. 29.33).
The sharp point is then passed into the tibia with a mallet and then
removed. The drill bit is then placed freehand through the hole and
through the nail. The AP view is checked, and the lateral tibia is
drilled and measured for placement of the screw. The screw should be 5
mm longer than the measurement so it will be easier to remove if it
breaks (Fig. 29.34). The screw should protrude
through the cortex; if the screw is not prominent, then it will be very
difficult to retrieve if breakage occurs (Fig. 29.35).
A lateral radiograph should be checked again to be absolutely certain
the screw is in the nail and that it has not moved anteriorly or
posteriorly (Fig. 29.36).

A long-acting local anesthetic is injected into all the
wounds. The wounds are then irrigated and closed. If necessary, the
patient is checked for increased compartmental pressure. Most grade I
and II open wounds and some grade IIIA fractures are closed primarily,
while

contaminated
IIIA fractures are left open and closed after a delay. Grade IIIB
fractures are scheduled for return to the operating room for repeated
debridements and early flap coverage.

Delayed union and nonunion of the tibia are common
complications of intramedullary nailing. A nonoptimal outcome is
related to the poor soft-tissue envelope around the tibia, which is
further compromised by the injury. Implant failure is common. Therefore
careful postoperative monitoring is important, and further surgical
procedures are expected in comminuted high-energy fractures.

Dynamization is an excellent choice of treatment for
stable-pattern fractures that are slow to heal at 2 or 3 months and
will not be excessively shortened or rotated. If callus is not evident
at 2 to 3 months in this group, then removal of screws at the end of
the nail farthest from the fracture is beneficial. Bone grafting is
used in patients with a skeletal defect. This treatment is most
effective when delayed: a 6 to 8 week interval appears to be
appropriate. Because these are unstable fractures and will shorten, a
static nail should be left in place.

Exchange nailing also is used for slow-healing stable
fractures. It is ideal for patients who were initially stabilized with
small-diameter nails and screws. Two to 3 months after injury, when the
soft tissues are well healed, a larger nail is placed; the fracture
pattern will dictate whether it is to be statically locked.

Screw failure occurs in 10% to 40% of statically locked
tibial nails. Weaker screws include those with small diameters and
those made of titanium. If screw failure occurs in a stable fracture
pattern, then surgery is not required, and the fracture will usually
heal. In unstable fracture patterns, including distal fractures, screw
breakage is frequently a precursor to a nonunion. In these patients,
the broken screws should be removed, and larger nails should be
inserted with larger screws in either a static or dynamic mode.

Nail breakage occurs in 3% to 5% of fractures, generally
after 4 to 6 months. Broken nails should be exchanged. For cannulated
nails with a large diameter, a hook can be used for removal. For
small-diameter cannulated nails, a bulb-tip guide with a smooth guide
rod alongside it can be used to remove the distal fragment. Removal of
the distal fragment is extremely difficult when solid nails are
employed, and we advise against using them.

Infection after nailing may be subclassified as acute or
chronic. In acute infections found within a week of surgery,
debridement and drainage is the treatment of choice. The nail can be
left in place, and for 6 weeks parenteral antibiotics are used. If the
infection resolves, the nail is left in place, and the patient is
followed until healing. If healing is slow, a posterolateral bone graft
may be necessary.

A chronic infection may indicate a possible segmental
sequestrum. In these patients, the nail and a segment of tibia must be
removed to eradicate the infection. These patients are then placed in
external fixators and require cancellous bone grafting for small
defects and segmental transport for large defects. Intravenous
antibiotics are necessary and should be administered for at least 6
weeks.

Compartment syndromes can be difficult to diagnose. They
generally occur within the first 24 to 48 hours after injury but can be
seen as late as 5 days following fracture. Frequent physical
examinations in an awake patient constitute the most reliable
diagnostic

technique,
and pressure measurements in the comatose or uncooperative patient are
the safest diagnostic techniques. Multiple pressure measurements are
particularly beneficial to determine a trend. In institutions with
frequent monitoring capabilities, the compartment pressure can increase
to within 30 mm Hg of diastolic pressure before a compartment release
is done. In situations in which monitoring is not optimal at night or
on the weekends, release of compartment at lower pressure and with
suggestive signs is advised. A four compartment fasciotomy can be
performed through either a single lateral incision or a lateral and
posteromedial incision. The posteromedial incision is the best choice
for distal injuries.