Functional and radiological outcome after delayed fixation of femoral neck fractures in pediatric patients

BACKGROUND: Complications that develop after femoral neck fracture in children—especially osteonecrosis—have been retrospectively attributed to inadvertent delayed fixation and fracture type. Prospective evaluation of results after delayed fixation of femoral neck fractures in children beyond the first 24 h is not reported in the literature and requires evaluation to increase our understanding of the procedure and improve fixation methods. Also, the role of capsular decompression in initial management needs to be elucidated. MATERIALS AND METHODS: Radiological and functional evaluation was done for delayed fixation (>24 h) of displaced fractures in the femoral neck in 21 children (21 hips) treated over 11 years. Mean patient age was 11.8 (median 12, range 5–15) years. Extraphyseal fixation was done using partially threaded cannulated cancellous screws after closed or open reduction. Patients were allowed full weight bearing after 12–18 weeks. Results were assessed on the basis of modified Ratliff criteria. Patients were followed for a mean of 81 (range 66–129) months. RESULTS: All fractures united at a mean duration of 12 (range 10.6–14) weeks. Three (14.3%) patients had osteonecrosis of the hip, which was significantly related to poor outcome (r = 0.495; P = 0.022). There was a significant correlation (r = 0.52) between development of osteonecrosis and delayed fracture fixation of >10 days (P = 0.016) and open reduction (P = 0.016). CONCLUSIONS: Outcome following temporal delay in fracture fixation of the femoral neck is primarily affected by osteonecrosis of the femoral head, whereas restriction of movements, shortening, and premature physeal closure has no significant influence. Osteonecrosis is primarily linked to delay and open reduction, whereas fracture type, age, and sex seem insignificant factors. Capsular decompression does not seem to affect the outcome in delayed presentations and may hinder definitive treatment.