Salter-Harris II Ankle Fractures in Children: Does Fracture Pattern Matter?

OBJECTIVES: To determine the correlation of Salter-Harris II fracture patterns with premature physeal closure (PPC) and resultant angular deformity of the ankle. DESIGN: Retrospective review. SETTING: Cincinnati Children's Hospital Medical Center (outpatient level of care). PATIENTS/PARTICIPANTS: We searched the digital ankle radiographs taken at our institution from 2001 to 2010, identifying all skeletally immature patients with confirmed ankle fractures. INTERVENTION: Fracture patterns were subclassified according to the Dias-Tachdjian classification system. Only patients with a minimum of 6 months of follow-up were included. MAIN OUTCOME MEASURES: Rates of PPC, initial operative interventions, subsequent surgical interventions, and final angular deformities of the ankle in the coronal plane were recorded and considered significant if more than 10 degrees. RESULTS: One hundred forty-one patients met our criteria. Fifty-two pronation-external rotation (PER) injuries, 35 supination-external rotation (SER) injuries, and 54 supination-plantar flexion (SPF) injuries were included. Of the PER injuries, 15 (28.8%) PPCs occurred with 6 patients having a resultant angular deformity of the ankle of at least 10 degrees at latest follow-up. Thirteen (24.1%) of the SPF patients went on to PPC with no resultant angular deformities. Of the SER injuries, 4 (11.4%) went on to PPC also with no patients having resultant angular deformities. The PER group had a statistically significantly higher rate of resultant angular deformity (P = 0.021). CONCLUSIONS: Salter-Harris II fractures of the ankle are common in children, with fracture pattern directly related to PPC and the chance for angular deformity. PER injuries are more likely to have a PPC associated with an angular deformity compared with SER and supination-plantar flexion injuries. The odds ratio of having an angular deformity with PER injuries compared with SER and SPF injuries is 25. SIGNIFICANCE: Fracture pattern of the ankle is related to growth disturbance, which must be taken into consideration when treating these injuries and addressed with the patient and family. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.