summary Pediatric Tibial Shaft Fractures are the third most common long bone fracture in children. Diagnosis can be confirmed with plain radiographs of the tibia. Treatment may be nonoperative or operative depending on the fracture morphology, age of the patient, and associated injuries. Epidemiology Incidence 15% of all pediatric fractures Demographics boys > girls average age of occurrence - 8 years Anatomic location 39% of tibia fractures occur in the mid-diaphysis Etiology Pathophysiology mechanism of injury adolescents most commonly due to pedestrian vs vehicle (50%) direct blow toddlers low energy twisting or falls torsional forces result in a spiral or oblique fracture pattern or a "toddler's fracture" Associated conditions orthopedic manifestations 30% are associated with a fibula fracture second most common fractured bone following nonaccidental trauma Anatomy Osteology tibia triangular shaped bone with apex anteriorly that broadens distally the anteromedial border is subcutaneous tibial flare distally leads to primarily cancellous bone and a thin cortical shell Muscles the anterior and lateral compartment musculature produce valgus deforming forces when both the tibia and fibula are fractured Blood supply posterior tibial a. provides nutrient and periosteal vessels the anterior tibial artery is vulnerable to injury as it passes through the interosseous membrane Biomechanics the fibula bears 6-17% of the weight-bearing load Classification Classification based on fracture location (proximal, midshaft, distal) and pattern Pediatric tibial shaft fracture patterns Incomplete Greenstick fracture of the tibia and/or fibula Complete Complete fracture of the tibia with or without ipsilateral fibula fracture or plastic deformation Tibial spiral fracture (Toddler's Fracture) Nondisplaced spiral or fracture of the tibia with intact fibula in a child under 2.5 years of age Presentation Symptoms pain bruising limping or refusal to bear weight Physical exam inspection warmth, swelling over fracture site palpation tender over fracture site motion pain on ankle dorsiflexion neurovascular always have high suspicion for compartment syndrome Imaging Radiographs recommended views AP and lateral views of the tibia and fibula are required ipsilateral knee and ankle must be evaluated to rule out concomitant injury optional views contralateral films of the uninjured leg findings radiographs may appear normal in toddler's fractures CT indications concern for physeal or intra-articular extension, pathologic lesion distal third tibia fractures may propagate to physis or articular surface MRI indications suspicion for pathologic or stress fracture rule out an occult fracture Bone scan indications rule out an occult fracture Treatment Nonoperative long leg casting indications almost all Toddler's fracture Greenstick fractures followup follow up x-rays in 2 weeks to evaluate for callus in order to confirm the diagnosis in equivocal cases closed reduction and long leg casting indications most traumatic fractures displaced with acceptable reduction 50% translation < 1 cm of shortening < 5-10 degrees of angulation in the sagittal and coronal planes mold cast to decrease likelihood of fracture displacement complete fractures with intact fibula tend to fall into varus complete fractures with fracture fibula tend to fall into valgus and recurvatum followup serial radiographs are performed to monitor for developing deformity serial followup if physeal extension to monitor for growth disturbance early weight bearing as soon as 1 week after cast placement is not only safe but may be beneficial to the child's recovery without negatively impacting healing rates Operative external fixation indications open or closed fractures with extensive soft tissue injury, length unstable fractures, or poly-trauma patients flexible intramedullary nails indications open or closed fractures in skeletally immature patients multiple long bone fractures or floating knee percutaneous pinning indications noncomminuted, unstable oblique fractures may be used with casting rigid intramedullary nailing indications open or closed tibial shaft fractures in patients at or near skeletal maturity plate fixation indications open or closed fractures with physeal or articular extension length unstable fractures nonunions or malunions Techniques Closed reduction and long leg casting conscious sedation or general anesthesia approach extend cast to the groin with the knee flexed to 30 degrees and appropriate molding +/- bivalve depending on swelling specific complications compartment syndrome loss of reduction may be corrected with opening or closing cast wedging External fixation soft tissue if open fracture debride and irrigate prior to placing pins instrumentation 2 half-pins above and below fracture in the tibia specific complications pin tract infection refracture nonunion (~2%) malunion Flexible intramedullary rods bone work drill holes are made in the proximal or distal tibial metaphysis instrumentation flexible rods are introduced into the proximal or distal tibial metaphysis and passed across the fracture site immobilization typically a short period of immobilization and non-weight bearing given flexibility of nails specific complications nonunion (~10%) malunion infection outcomes shorter immobilization compared to casting (3 months) Complications Compartment syndrome incidence less common than adult tibial shaft fractures risk factors open and closed fractures treatment emergent fasciotomies indications similar to adults 3 As: analgesia, anxiety, agitation Leg-length discrepancy risk factors children <10 comminution may lead to overgrowth iatrogenic pin placement may lead to growth arrest or recurvatum from tibial tubercle arrest Angular deformity risk factors complex deformity valgus and apex posterior deformity physeal extension treatment corrective osteotomy indication rotational malunion symptomatic and at risk of joint degeneration Associated physeal injury risk factors open and closed fractures distal fractures treatment reduction and follow-up Delayed union and nonunion incidence 25% in open tibia fractures risk factors increasing age increasing severity of wound treatment determined by type of nonunion hypertrophic: bone grafting and rigid fixation oligotrophic or atrophic: bone grafting and fixation, +/- resection Prognosis Healing 3 to 4 weeks for toddler's fracture 6 to 8 weeks for other tibial fractures