When predicting complications associated with displaced physeal fractures of the distal femur, the direction and amount of displacement does not statistically correlate with outcome.
Distal femoral physeal fractures are uncommon but have a high incidence rate of complications. These should, in general, be treated with internal fixation unless the fracture is truly nondisplaced. Repeated reduction attempts should also be avoided, as this can lead to increased physeal damage. Overall, the most common complication is growth arrest. Salter-Harris II fractures, specifically, should be treated with open reduction and internal fixation with lag screws in the metaphysis and crossing of the physis with hardware should be avoided if possible.
Arkader et al. retrospectively reviewed the medical charts and images of 73 patients who sustained a distal femoral physeal fracture. The outcomes they evaluated included growth arrest, leg length discrepency, and angular deformity. The SH classification significantly correlated with the incidence of complications, and there was also a significantly higher incidence rate of complications among displaced fractures. However, the amount and direction of displacement did not correlate with the outcome. The group treated conservatively had a lower incidence rate of complications than did the surgical group, however this was felt to be due to selection bias because the most severe fractures were treated surgically. Among the surgical group, a higher incidence rate of complications occurred when the physis was violated by hardware.
Figure A is a lateral radiograph of the distal femur which shows anterior displacement of the distal femoral epiphysis from the main portion of the femur.
Answer 1,2,3,5: All of these are predictive of outcomes with physeal injury of the distal femur.
Arkader A, Warner WC Jr, Horn BD, Shaw RN, Wells L. Predicting the outcome of physeal fractures of the distal femur. J Pediatr Orthop. 2007 Sep;27(6):703-8.
PMID:17717475 (Link to Abstract)