summary Tillaux Fractures are traumatic ankle injuries in the pediatric population characterized by a Salter-Harris III fracture of the anterolateral distal tibia epiphysis. Diagnosis can be made with plain radiographs of the ankle. CT scan may be required to further characterize the fracture pattern and for surgical planning. Treatment is closed reduction and casting if < 2mm displacement or operative management if > 2mm displacement. Epidemiology Incidence accounts for 3-5% of pediatric ankle fractures demographics more common in girls seen in children nearing skeletal maturity (12-14 years old) typically occur within one year of complete distal tibia physeal closure due to pattern of progression of physeal closure older than triplane fracture age group Etiology Pathophysiology caused by an avulsion of the anterior inferior tibiofibular ligament mechanism of injury results from supination-external rotation injury leads to avulsion of anterolateral tibia at the site of attachment of the anterior inferior tibiofibular ligament lack of coronal plane fracture in the posterior distal tibial metaphysis distinguishes this fracture from a triplane fracture Associated conditions distal fibular fracture (usually SH I or II) ipsilateral tibial shaft fracture Anatomy Physeal considerations distal tibial physis accounts for 35-40% of overall tibial growth and 15-20% of overall lower extremity growth rate of growth is 3-4 mm/year growth continues until 14 years in girls and 16 years in boys closure occurs during an 18 month transitional period Occurs in a predictable pattern: central > anteromedial > posteromedial > lateral Ligaments anterior inferior tibiofibular ligament (AITFL) extends from anterior aspect of lateral distal tibial epiphysis (Chaput tubercle) to the anterior aspect of distal fibula (Wagstaffe tubercle) Presentation Symptoms pain inability to bear weight Physical exam inspection slight swelling focal tenderness at anterolateral joint line deformity is rare marked displacement is prevented by the fibula Imaging Radiographs recommended views AP lateral mortise best view to see tillaux fractures findings SH III fracture of the anterolateral distal tibia epiphysis CT scan indications delineate fracture pattern determine degree of displacement identify intramalleolar or medial fracture variant patterns Treatment Nonoperative closed reduction and casting indications < 2mm displacement following closed reduction (rare) Operative CRPP vs. ORIF indications > 2mm displacement remains after reduction attempt Techniques Closed reduction and casting reduce by internally rotating foot can also attempt by dorsiflexing the pronated foot then internally rotating CT scans sometimes needed to determine residual displacement (confirm < 2mm) long leg cast initially for 3-4 weeks to control rotational component of injury follow early with radiographs to assess for displacement immobilize an additional 2-4 weeks in a short leg cast or walking boot (to initiate ankle ROM) CRPP reduction use k-wire or guidwire as joystick for reduction assess reduction with flouroscopy or arthrogram in OR (if in doubt, open the joint and viusalize) instrumentation K-wire or cunnulated screw over guidwire can be final fixation it is OK to cross physis with fixation as there is little growth remaining outcomes functional outcomes are good with a residual displacement of < 2.5mm ORIF approach anterolateral approach visualize joint line to optimize reduction reduction reduce with internal rotation arthroscopically-assisted reduction has been described indirect reduction with periarticular clamp and percutaneous fixation has also yielded good results instrumentation intraepiphyseal K wires or cannulated screws transphyseal fixation can also be used as most patients are approaching skeletal maturity post-op long leg cast for 3-4 weeks then short leg walking cast for 2 weeks Complications Premature growth arrest rare physeal closure is already occuring decreased risk with anatomic reduction Early arthritis increased risk with articular displacement