Physeal fractures of the distal femur: does a lower threshold for surgery lead to better outcomes?

Distal femur physeal fractures are known to have a high incidence of complications. Our previous reported experience (pre-2007) showed a 40% complication risk, which prompted changes in our approach. The purpose of this study was to evaluate and compare the complication rate and outcome after implementation of these changes. This is a retrospective study of children with distal femur physeal fractures treated at a level 1 pediatric trauma center between 2007 and 2016. Patient demographics, fracture patterns, treatment and outcomes including complications and its risk factors were recorded and analyzed. We compared current results with our previously reported multicenter cohort (n = 73). Patients were male in majority (57/70) with a mean age of 13 +/- 4 years. Fractures were most commonly Salter-Harris Type 2 (49/70) and displaced (59/70) on presentation, although neither characteristic was associated with complications. Most patients (63/70) were treated surgically, and the overall complication incidence was 36% (25/70), including growth arrest in 20 patients. The pre-2007 cohort was statistically significantly younger (P< 0.001) and was more commonly treated nonoperatively (P< 0.001). However, there was no statistically significant difference in complication incidence between studies (36% versus 40%, respectively,P= 0.751). Despite a lower threshold for surgery for distal femur physeal fractures in the past decade, the complication rate is still high and unchanged at 40%, and presenting patients are older. There were no new prognostic factors that showed statistically significant association with subsequent complications; however, patients with high-energy injury mechanisms and greater fracture displacements did have higher complication rates. These results demonstrate the inherent high complication risk for these injuries. Level of Evidence: III.