Remodeling in Patients with in Situ Fixation for a Slipped Capital Femoral Epiphysis

Objective: This study has investigated the amount of bone remodeling in patients with a slipped capital femoral epiphysis (SCFE) treated with in situ fixation until closure of the epiphysis and the factors affecting remodeling. Method: Patients who underwent surgery for SCFE between January 2010 and January 2015 were retrospectively screened: Twenty-four male and 7 female patients (mean age 12.6 ± 1.9 years) were included in the study. Gender, age, history, and laterality of trauma, duration of hip pain (acute, chronic, acute on chronic background), and hip radiographs were evaluated. The Southwick and alpha angles were measured, and the factors affecting remodeling were assessed. The statistical analyses were conducted using SPSS 25.0 (IBM Corp., Armonk, NY); 95% confidence levels were calculated and p < 0.05 was considered to indicate statistical significance. Results: The preoperative displacement angles measured on the anteroposterior and lateral radiographs were 15.03° ± 9.1° and 25.93° ± 14.1° and at the last follow-up they were 11.63° ± 8.7° and 21.6° ± 12.1°, respectively. The alpha angles measured on the lateral radiographs preoperatively and at the end of follow-up were 52.33° ± 11.6° and 47.87° ± 11.8°, respectively. Significant remodeling was reflected in the angles measured on the anteroposterior and lateral X-ray images. Greater preoperative displacement angle was associated with less remodeling. Conclusion: Preoperative displacement affects the degree of postoperative remodeling. In patients with severe epiphyseal displacement, open reduction is an option but in situ pinning should be considered in that it is less invasive and more physiological.