Factors influencing the development of avascular necrosis in non-operative treatment of the acute slipped capital femoral epiphysis

INTRODUCTION: The acute slipped capital femoral epiphysis can result in development of avascular necrosis of the femoral head which is very difficult condition to treat. Orthopedic surgeon can influence the development of avascular necrosis. OBJECTIVE: The main objective in our study was to identify factors influencing the development of avascular necrosis in nonoperative treated patients for the acute slipped capital femoral epiphysis. METHOD: A total of 53 patients and 59 hips treated for the acute slipped capital femoral epiphysis at the Institute for Orthopedic Surgery,Banjica" between 1968-2004 were studied. Necessary data were obtained from the accurate medical records. RESULTS: Avascular necrosis of the femoral head was diagnosed in 8 patients (13.56%). Six of them (75%) were treated by manipulative reduction in general anesthesia and spica cast immobilization. Fischer test, used for statistical data processing, found significant difference between two non-operative methods of treatment (p = 0.0008). CONCLUSION: Higher-degree epihyseal displacement as well as complete separation of the physis and metaphysis were found to be the risk factors of avascular necrosis. Every manipulation with the affected hip was also associated with higher percentage of avascular necrosis of the femoral head.