مرکز منطقه ای اطلاع رساني علوم و فناوري - The effect of slip grade and chronicity on the development of femur avascular necrosis in surgically treate d slipped capital femoral epiphyses

Latin Abstract :

Objectives: We investigated the relationship between the grade and chronicity (acute-chronic) of the slip and the devel¬opment of avascular necrosis (AVN) of the femoral head after surgery for slipped capital femoral epiphysis (SCFE). Methods: The study included 424 hips of 269 patients (174 boys, 95 girls; mean age 12 years) who underwent surgery for SCFE and had a minimum follow-up period of one year. The patients were classified according to the severity and chronicity of the slipping using the Southwick classifica¬tion. The relationship of the slip severity and chronicity with the development of AVN was statistically evaluated. Results: Involvement was unilateral in 114 patients, and bilateral in 155 patients. The mean follow-up period was 32.9 months. The hips were classified as grade I to II in 267 hips (63%), 120 hips (28.3%), and 37 hips (8.7%), respectively. The symptoms were acute in 130 hips (30.7%), and chronic in 294 hips (69.3%). The incidence of AVN was 4.5% (19 hips; 13 in unilateral cases, 6 in bilateral cases). In logistic regression analysis, a strong correlation was found between the grade of the slip and the development of AVN (odds ratio 10.27; p<0.0001). The acute nature of the slip was also correlated with the development of AVN, but this relation was weaker (odds ratio 0.20, p<0.01). Conclusion: A strong correlation is present between the slipping grade and the development of AVN in SCFE, requiring a closer observation of patients having a high grade slipping in terms of AVN risk. The acute nature of the symptoms represents another risk factor for AVN.