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C H A P T E R 30 Pediatric Tibial Fractures Craig P. Eberson

DEFINITION

or high-energy ones, such as seen in car versus pedestrian accidents (direct blow, comminuted fracture). ■ Many injuries fall somewhere along the spectrum. ■ High-energy injuries often are seen with concomitant inju- ries, such as ipsilateral femoral injuries (the so-called floating knee), compartment syndromes, and intra-articular injuries of the proximal or distal tibia. 11 ■ Occasionally, the fracture may be pathologic through an un- derlying bone lesion (eg, nonossifying fibroma, aneurysmal bone cyst, osteomyelitis, osteosarcoma). ■ As in all fractures in young children, child abuse must be suspected if the history is unclear or multiple fractures are present. NATURAL HISTORY ■ Because of the significant remodeling potential in young children, most patients heal without sequelae. ■ Morbidity from associated injuries, however, may be signifi- cant (ie, compartment syndrome), so a thorough evaluation is of paramount importance. ■ General guidelines are available to define acceptable healing alignment (Table 1).

■ Fractures of the tibia are common in children. ■ Severity ranges from nondisplaced “toddler’s” fracture to high-energy open injury. ■ Open growth plates at the ends of the tibia preclude stan- dard adult treatment options such as solid interlocked nails. ■ Many cases can be managed nonoperatively, but orthopae- dists need to maintain familiarity with operative techniques. ■ Relevant anatomy includes muscle compartments (anterior, posterior, superficial, and deep posterior), cross-sectional shape, and growth plates ( FIG 1 ). ■ Neurovascular structures are at risk from direct trauma or compartment syndrome. ■ Understanding the anatomy of the growth plates is crucial when planning fixation techniques.

ANATOMY

PATHOGENESIS

■ The most common injury scenarios are either low-energy in- juries, such as those sustained during sports (twisting injury),

Anterior compartment

Lateral compartment Extensor digitorum longus Extensor hallucis longus Anterior tibial artery and vein Deep peroneal nerve Tibialis anterior

Popliteal artery

Tibia

Deep posterior compartment Tibialis posterior

Anterior tibial artery

Flexor digitorum longus

Peroneus longus Peroneus brevis Superficial peroneal nerve

Flexor hallucis longus Posterior tibial artery and vein

Posterior tibial artery

Fibula

Tibial nerve

Superficial posterior compartment Soleus Gastrocnemius

Adipose tissue

Peroneal artery

A

FIG 1 ● A. Cross-sectional anatomy at the midtibial level. Note the triangular shape of the tibial shaft; this is important when placing external fixator pins. B. Arterial supply of the leg viewed from posteri- orly. The anterior tibial artery penetrates the interosseous membrane proximally and is tethered there, putting it at risk for injury in proximal fractures. C. Proximal tibial physis viewed laterally. It is important to appreciate the continuity of the tubercle and proximal tibial growth plates. Injury to the tubercle growth plate will result in a recurvatum deformity.

C

B

254

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Chapter 30 Pediatric Tibial Fractures

IMAGING AND OTHER DIAGNOSTIC STUDIES ■ Standard anteroposterior (AP) and lateral radiographic views should be obtained. ■ For complex fractures, dedicated knee and ankle films can be helpful to evaluate for extension into the physeal or articular regions. ■ Computed tomography can be helpful to assess these regions if radiographs do not provide sufficient clarity. ■ Contralateral full-length films are helpful for determining length in comminuted fractures. DIFFERENTIAL DIAGNOSIS

Table 1 Acceptable Deformity for Fractures of the Tibia Acceptable Deformity by Patient Age Parameter Under 8 Years 8 Years or Older Valgus 5 degrees 5 degrees Varus 10 degrees 10 degrees Apex anterior/posterior

Angulation Shortening Malrotation

10 degrees 10 mm 5 degrees

5 degrees 5 mm 5 degrees

Adapted from Heinrich SD. Fractures of the shaft of the tibia and fibula. In: Beaty JH, Kasser JR, eds. Rockwood and Wilkins’ Fractures in Children, ed 5. Philadelphia: Lippincott Williams & Wilkins, 2001:1077–1119; Wilkins KE. Principles of fracture remodelling in children. Injury 2005;36(suppl 1):A3–A11.

■ Isolated tibial fracture ■ Floating knee ■ Pathologic fracture ■ Intra-articular or intraphyseal injury ■ Compartment syndrome ■ Child abuse NONOPERATIVE MANAGEMENT

PATIENT HISTORY AND PHYSICAL FINDINGS ■ The history should include mechanism of injury, anteced- ent pain, neurologic symptoms, and other areas of pain (eg, femur, abdominal pain, headache). ■ A high-energy injury should also prompt a full trauma workup using standard Advanced Trauma Life Support protocols. ■ The physical examination should focus on assessing initial displacement and skin condition (ie, open injury) as well as swelling of the compartments. ■ The limb should be splinted, in the case of gross deformity, before obtaining films using a material that permits high- quality radiographs. ■ A thorough neurovascular examination is needed to assess for vascular injury or compartment syndrome. 1 ■ Pulses should be palpated or obtained with Doppler assistance. ■ Sensation in the deep and superficial peroneal nerve and tibial nerve distributions should be assessed as well as motor function (toe flexors–extensors). ■ Pain with passive motion of the toes may represent an evolving compartment syndrome. More specifically, increasing pain, or pain out of proportion to the in- jury, is often the first early warning sign and should be taken seriously. Splitting or removal of casting material should be performed if any question exists. In young children, anxiety and fearfulness may be the presenting feature. ■ Compartment pressure measurements should be obtained in cases of concern ( FIG 1A ). ■ Compartment syndrome is signaled by tense swelling of the compartment, pain with gentle squeezing of the com- partment, pain with passive extension–flexion of toes, and paresthesias in involved nerve distributions. Loss of pulse is a late finding. ● Patients with any of these signs should be considered at risk. ■ A low threshold should be present for measuring compart- ment pressures and performing fasciotomy as needed. ■ Vigilance is required to prevent permanent sequelae due to missed compartment syndrome.

■ Most tibial fractures can be managed with closed reduction and cast immobilization in an above-the-knee cast. ■ The cast should be molded to the anatomy of the tibia. ■ A supracondylar “squeeze” mold above the knee and 15 to 20 degrees of knee flexion can prevent cast slippage. ■ To truly avoidweight bearing, however, the cast must be flexed at least 70 to 80 degrees (if appropriate for a specific fracture). ■ In cases of acute fracture, the cast can be univalved or bivalved to allow for swelling. It can then be overwrapped before initiating weight bearing. ■ Weekly radiographs are obtained for the first 3 weeks, with the cast being wedged or changed as needed for loss of alignment. ■ Weight bearing is dictated by patient comfort. ■ The cast is changed to a short-leg or patellar-bearing cast after 4 to 6 weeks, and immobilization is continued until healing is complete. ■ Surgical management is required for inability to maintain satisfactory alignment (see Table 1). SURGICAL MANAGEMENT ■ Indications for surgical treatment of tibial fractures in chil- dren include open injuries, compartment syndrome, multiple injuries, and fractures for which closed treatment fails. ■ Treatment in mature adolescents is the same as for adults with reamed, locked intramedullary nails. ■ Younger children’s open physes require techniques that avoid the proximal and distal tibia, such as external fixation, plate fixation, and elastic intramedullary nailing. ■ Traditionally, external fixation was used primarily for frac- tures with significant comminution or soft tissue injury, where intramedullary fixation was considered impractical. However, recent work challenges this paradigm for surgeons experienced with elastic nailing. 12 ■ Rapid stabilization of the multiply injured child is often accomplished using external fixation as well. 4,7,9,13 ■ Plate fixation is a helpful technique for fractures not ame- nable to elastic nail fixation. ■ It is particularly helpful in patients who present with late loss of reduction and require an open approach to remove callus and align the fracture.

257

Chapter 30 Pediatric Tibial Fractures

T E C H N I Q U E S

TECH FIG 1 ● A. External fixation in a patient with a compart- ment syndrome. Arrows mark the proximal and distal growth plates. The proximal pins start fairly distally to avoid the tubercle physis. B. In this patient, an external fixator was used for a grade 2 open fracture treated with delayed closure. The patient also had a degloving injury requiring a flap and skin graft over the medial ankle. The frame was extended to the first metatarsal to immobi- lize the foot during healing. Although somewhat bulky, the “double stack” configuration of the frame allows for easy dynamization.

A

B

■ Plate Fixation ■ Treatment is essentially the same as for adult injuries, but several points bear emphasis. ■ It is helpful to make the incision slightly laterally over the anterior compartment so it will not lie directly over a medially placed plate ( TECH FIG 2A ). ■ The fracture is reduced using standard techniques. Care should be taken to avoid unnecessary stripping of the fracture. ■ I prefer to make an incision over the fracture large enough to reduce the fragments but not the entire length of the plate. ■ The plate can be slid under the skin, over the periosteum, and the screws placed through stab incisions, as for percu- taneous plating in adults ( TECH FIG 2B ). ■ For larger children, many adult fracture systems include precon- toured 3.5-mm plates for the distal tibia. ■ For smaller children, a small fragment plate may be con- toured to fit appropriately. ■ It is important to avoid injury to the perichondral ring at the distal extent of the plate. ■ If the plate is applied on the medial side of the tibia, as it often is for fractures with valgus angulation, it will usually need to be removed after healing due to prominence. ■ If applied laterally, I usually make a longer incision because per- cutaneously placed screws will traverse the anterior compart- ment and potentially injure the neurovascular bundle. I prefer open placement in this case. ■ The wound is closed using standard techniques. A posterior splint is applied to protect the soft tissues.

Lag screw Plate

Stab incisions for screws

A B TECH FIG 2 ● A. Incision for open reduction and internal fixation is made laterally over the anterior compartment, and the skin can then be mobilized to gain access to the fracture site. It is important not to incise the skin directly over the proposed location of the plate. B. Medial view of internally fixed tibia. A lag screw compresses the fragment, and the plate stops short of the physis. The skin incision is centered over the fracture to allow an accurate reduction, but the proximal and distal screws can be placed percutaneously through a medially applied plate. It is helpful to make one stab incision for every two holes, centered between them.

258

Operative Techniques in Pediatric Orthopaedic Surgery

■ Elastic Intramedullary Nail Fixation ■ The surgeon begins by selecting the proper nail size. Usually, nails should be 0.4 times the diameter of the tibial isthmus. ■ The nails are contoured so that there is a C shape with its apex at the fracture site. This will cause cortical contact at the apex, yielding three-point fixation (proximal, cortical at fracture level, and distal). ■ By contouring rods of equal diameter symmetrically, the elastic- ity of the nails resists deformation of the fracture, as opposed to reamed nailing, where the fracture is statically supported by the strength of the nail. Preparation for Nail Insertion ■ The nails are inserted in the tibial metaphysis. ■ The proper starting point is at least 1 cm distal to the proxi- mal tibial physis and 2 cm posterior to the tibial tubercle physis ( TECH FIG 3A,B ). ■ The relevant landmarks should be identified fluoroscopically and marked on the skin (physis, tubercle, starting points) before pro- ceeding ( TECH FIG 3B ). ■ The incision should be 1 to 1.5 cm long, with its most distal extent roughly 1 cm proximal to the physis. ■ This will allow an oblique passage of the nail at the correct proximal to distal angle. ■ A small hemostat is used to carefully spread through the tissue down to bone, and a drill sleeve and drill are placed on the bone. The drill should be 1 to 1.5 mm larger than the diameter of the nail.

■ After checking the position of the drill tip with fluoroscopy ( TECH FIG 3C ), a starting hole is drilled along the proposed path of the nail ( TECH FIG 3D ). ■ Care is taken not to drill across the tibia out the opposite cortex. ■ Alternatively, an awl can be used by hand to create this opening in the cortex. Nail Pattern and Placement ■ Multiple nail patterns have been described, 6 but the standard is one medial and one lateral nail ( TECH FIG 4A,B ). ■ Alternately, if soft tissue compromise precludes the use of an entry site, the first nail is bent into a C shape, with the second bent into an S shape. The apex of the more distal curve in the nail should be at the fracture site. ■ The first nail is contoured into a C shape. It should be placed on the tibia and a fluoroscopic image obtained ( TECH FIG 4C,D ). ■ A gentle bend is placed in the nail, centered at the fracture. ■ The nail is placed up to the fracture site under fluoroscopic guid- ance. Initially, it is helpful to direct the bend posteriorly, as in the passage of a guidewire for a standard reamed nail, but it is important to rotate the bend into the proper plane to prevent a recurvatum deformity ( TECH FIG 4E,F ). ■ The second nail is placed in the same fashion. Fracture Reduction and Fixation ■ The fracture is then manually reduced. ■ It is rarely necessary to open the fracture to obtain a reduc- tion, as the fracture can be easily manipulated.

T E C H N I Q U E S

2 cm

1 cm

A

B

C

TECH FIG 3 ● A. The proper starting point for nail insertion lies at least 1 cm distal to the proximal tibial growth plate and 2 cm posterior to the tubercle physis. B. Patient undergoing elastic intra- medullary nailing of the tibia. Marked on the skin are the proximal growth plate and proposed entry sites as well as the fracture. The incision is made proximal to the line of the physis, and an oblique angle matching the final path of the nail is dissected with a he- mostat down to the bone. C. After confirming the entry site radio- graphically, a drill is used through a guide to open the cortex 1 to 2 mm larger than the nail diameter. D. The drill starts perpendicular to the bone and is advanced distally. Care is taken not to drill into a previously placed nail or through the far cortex.

D

259

Chapter 30 Pediatric Tibial Fractures

T E C H N I Q U E S

A

B

D

E

F

TECH FIG 4 ● A,B. Potential patterns of nail insertion. The standard pattern ( A ) entails one medial and one lateral nail. Alternately, both nails are inserted from the same side to avoid com- promised skin ( B ). In the tibia, the former technique is far easier. C. The nail is placed on the skin, with the tip at the proposed final location, as confirmed radiographically. D. The nail is marked at the fracture site and bent to place the apex at that location. E. When starting a nail, it is helpful to rotate the nail so that the tip points anteriorly, bouncing off the posterior cortex. F. The nail is then turned so that the bend in the nail lies in the coronal plane.

C

■ Cutting the Nails and Wound Closure ■ The nails are then cut, pulling them away from the bone without exceeding the elastic modulus of the nail, so they lie against the bone after they are cut, with about 2 cm of the nail extending out of the bone to facilitate later. ■ Alternately, the nails can be withdrawn a few centi- meters, cut short, and then impacted back down the ■ The bent tip of the nail can be used to assist in reduction as well. ■ To pass the nails across the fracture, it is helpful to consider the initial deformity of the fracture. ■ For example, if the fracture tends to lie in valgus, it may be helpful to pass the medial nail first to apply a varus force. The second nail is then directed across the frac- ture site.

tibia, again leaving 2 cm of exposed nail beyond the entry site. ■ This step is important because if the nails are left too long or are bent out away from the bone, they can cause symptoms from nail prominence before fracture healing. This is especially true medially, where the rod is subcutaneous ( TECH FIG 5 ). ■ The incisions are closed with subcuticular suture, and a posterior splint is applied to allow tissue healing. ■ Care should be taken to stop the nails short of the distal physis and to avoid distraction at the fracture site. ■ When passing the nails, it is often helpful to pass them both to the level of the fracture and sequentially crossing the fracture site. ■ In oblique fractures, the first nail will deform the fracture and make passing the second nail difficult if the first nail is passed all the way down initially. ■ In simple fractures, the order of passage is less important.

TECH FIG 5 ● Instead of cutting the nail under the skin, it can be withdrawn, cut at skin level ( A ), and tamped in to prevent irritation ( B ).

B

A

260

Operative Techniques in Pediatric Orthopaedic Surgery

PEARLS AND PITFALLS

Compartment syndrome

■ A high index of suspicion is required. ■ The surgeon must maintain vigilance throughout the postoperative period for late development. ■ Increasing pain and anxiety are the first signs of pediatric compartment syndrome. ■ Rigid frames may lead to delayed union. ■ Care should be taken to use appropriately sized pins and to dynamize early. ■ Fluoroscopic guidance is used to avoid growth plates. ■ Incisions should be carefully chosen to avoid compromised skin. ■ Low-profile plates may help avoid irritation from the plate before fracture healing. ■ Fractures that are very distal or proximal, or highly comminuted, should be treated by other techniques. ■ Proper nail contouring and size selection are important to maintain stability of the fracture. ■ The nails should be the same diameter to provide balanced fixation ( FIG 4A ). ■ Nails should be passed carefully to avoid the “creeping vine” effect. ■ If the nails spiral around each other, the elastic recoil, and thus the stability of the technique, will be lost ( FIG 4B ).

External fixation

Plate fixation

Elastic intramedullary

■ Care should be taken to avoid physeal injury. ■ Nails should be cut short to avoid irritation.

FIG 4 ● Potential pitfalls in nail placement. A. The nails are of differing diameter, inducing a valgus moment that needs to be controlled in a cast. Note the incidental nonossifying fibroma. B. “Spiraling nails.” The elasticity afforded by three-point fixation is lost, making the construct less stable.

A

B

POSTOPERATIVE CARE

■ In general, prolonged stiffness is unusual in pediatric patients. ■ It is better to overimmobilize in questionable cases to avoid malalignment and regain motion later with aggres- sive physiotherapy. ■ Removal of symptomatic hardware (ie, nails or plate) should be delayed until fracture healing and remodeling are complete. ■ I prefer to remove elastic nails electively in all patients 6 to 12 months after injury, as the nails will become com- pletely intramedullary with significant continued growth, thus making late removal extremely difficult. ■ Ideally, plate removal is delayed for a year, after remodel- ing is complete. ■ Most tibial fractures in childrenwill heal uneventfully, although healing difficulties can occur, especially in older patients. 5,10 ■ Slongo 15 noted that most complications seen in his series were a result of improperly applied technique, particularly residual distraction at the fracture site, leading to a “pseud- arthrosis model” even in children. ■ Bar-On and associates 2 noted increased callus formation and shorter time to union in the elastic intramedullary nailing group versus external fixation (7 weeks compared with 10) in a femur model.

■ For patients treated with external fixation, a splint is used for 7 to 10 days to allow the tissues to recover. ■ For stable fractures, progressive weight bearing is initiated in reliable patients. ■ Unstable or comminuted fractures require waiting until visible callus is present before weight bearing. ■ Depending on fracture stability, dynamization of the fix- ator is initiated early, after sufficient callus is seen. The frame is removed in the office or the operating room after healing is noted radiographically. ■ Most patients benefit from short-term support with a bivalved cast after removal. ■ Patients treated with plate fixation begin a progressive weight-bearing program, with immobilization discontinued after sufficient radiographic healing is present, usually by 6 weeks. ■ Patients treated with elastic intramedullary fixation are usu- ally splinted for 7 to 10 days, followed by progressive weight bearing. The plan is modified based on fracture stability, soft tissue injury, and patient reliability. ■ Patients with substantial (over 50%) cortical contact may begin weight bearing as tolerated after soft tissue healing has occurred.

OUTCOMES

261

Chapter 30 Pediatric Tibial Fractures

■ Myers and coworkers 12 reported a significant complication rate in high-energy tibial fractures treated with external fixa- tion, including delayed union, malunion, leg length discrep- ancies, and pin tract infections. ■ Kubiak and colleagues 8 reported 2 delayed unions, 2 mal- unions, and 3 nonunions in a series of 15 patients man- aged with external fixation, although these appear to have occurred in open injuries. ■ They reported higher functional scores in their patients treated with elastic intramedullary nailing compared to external fixation. ■ Operative techniques usually require additional procedures for removal of pins or prominent nails or plates. ■ Obviously, operative complications do not occur in nonop- eratively treated patients. Knowledge of proper indications is crucial to maximize outcomes.

3. DeLong WG Jr, Born CT, Marcelli E, et al. Ender nail fixation in long bone fractures: experience in a level I trauma center. J Trauma 1989;29:571–576. 4. Furlan D, Pogorelic´ Z, Biocˇic´ M, et al. Elastic stable intramedullary nailing for pediatric long bone fractures: experience with 175 frac- tures. Scand J Surg 2011;100(3):208–215. 5. Gicquel P, Giacomelli M, Basic B, et al. Problems of operative and non-operative and healing in tibial fractures. Injury 2005;36(suppl 1): A44–A50. 6. Goodwin RC, Gaynor T, Mahar A, et al. Intramedullary flexible nail fixation of unstable tibial diaphyseal fractures. J Pediatr Orthop 2005;25:570–576. 7. Hunter JB. The principles of elastic stable intramedullary nailing in children. Injury 2005;36(suppl 1):A21–A24. 8. Kubiak EN, Egol KA, Scher D, et al. Operative treatment of tibial fractures in children: are elastic stable intramedullary nails an im- provement over external fixation? J Bone Joint Surg Am 2005;87(8): 1761–1768. 9. Lascombes P, Huber H, Fay R, et al. Flexible intramedullary nailing in children: nail to medullary canal diameters optimal ratio. J Pediatr Orthop 2013;33(4):403–408. 10. Lascombes P, Nespola A, Poircuitte JM, et al. Early complications with flexible intramedullary nailing in childhood fracture: 100 cases managed with precurved tip and shaft nails. Orthop Traumatol Surg Res 2012;98(4):369–375. 11. Moulton SL. Early management of the child with multiple injuries. Clin Orthop Relat Res 2000;(376):6–14. 12. Myers SH, Speigel D, Flynn JM. External fixation of high-energy tibia fractures. J Pediatr Orthop 2007;27:537–539. 13. Norman D, Peskin B, Ehrenraich A, et al. The use of external fixators in the immobilization of pediatric fractures. Arch Orthop Trauma Surg 2002;122:379–382. 14. O’Brien T, Weisman DS, Ronchetti P, et al. Flexible titanium nailing for the treatment of unstable pediatric tibial fracture. J Pediatr Orthop 2004;24:601–609. 15. Slongo T. Complications and failures of the ESIN technique. Injury 2005;36:A78–A85.

COMPLICATIONS

■ Malunion ■ Delayed union ■ Leg length discrepancy ■ Compartment syndrome ■ Symptomatic hardware ■ Infection

REFERENCES 1. Bae DS, Kadiyala RK, Waters PM. Acute compartment syndrome in children: contemporary diagnosis, treatment, and outcome. J Pediatr Orthop 2001;21:680–688. 2. Bar-On E, Sagiv S, Porat S. External fixation or flexible intramedul- lary nailing for femoral shaft fractures in children. A prospective, ran- domised study. J Bone Joint Surg Br 1997;79(6):975–978.

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