Closed Reduction, Osteotomy, and Fibular Graft Are Effective in Treating Pediatric Femoral Neck Pseudarthrosis After Infection

BACKGROUND: When treatment of acute septic arthritis of the hip is delayed, severe sequelae can occur. This may take the form of coxa breva, vara, or valga. Pseudoarthrosis of the femoral neck is a rare complication with only a few studies to guide treatment. QUESTION/PURPOSES: In a small series of patients with pseudarthrosis of the femoral neck after acute septic arthritis, we wanted to determine (1) whether femoral neck union can be achieved using a variety of surgical approaches; (2) whether these patients satisfied criteria outlined by Hunka and Choi, defined as a stable hip, a flexion arc ≥ 70° and no fixed adduction or abduction contractures, fixed flexion deformity not more than 20°, pain relief, and restoration of activities of daily living after surgery; and (3) any treatment-related complications if observed. METHODS: We reviewed the charts of patients who had presented to the orthopaedics outpatient department at Lady Hardinge Medical College and Associated Hospitals with the diagnosis sequelae of septic arthritis of the hip. Between 2003 and 2014, a total of 54 pediatric patients (61 hips) with sequelae of a septic hip had undergone various hip reconstructive procedures. Of these, 16 patients (30%) were diagnosed with pseudarthrosis of the femoral neck and were included in this study. All patients with this diagnosis were treated surgically. In this group, the median age at first contact with our treating team was 48 months (range, 18-96 months). The age of onset of the initial infection was 0.3 months to 84 months (median, 8 months). These 16 patients underwent a total of 24 surgical procedures to achieve union at the pseudoarthrosis site. We performed close reduction, fibula graft, and valgus osteotomy in most of the patients. Wagner's double intertrochantric osteotomy with a fibula graft was done in patients in whom there was a short femoral neck along with pseudoarthrosis. In all patients, the pseudarthrosis site was not exposed. Median followup was 6 years (range, 3-12 years). No patient was lost to followup before 3 years. Union was defined when there was complete radiologic healing at the pseudoarthrosis site. All the patients were clinically evaluated as per Choi's criteria. Parents were also asked about daily activities and pain. Other related complications were also recorded. RESULTS: Fifteen of 16 patients achieved union at the pseudarthrosis site within 6 to 24 months (median, 9 months). Ten patients underwent a single procedure to achieve union, whereas four patients underwent two surgical procedures and two patients underwent three procedures. Fifteen patients achieved Choi's criteria and one patient could not achieve this. While attempting this reconstruction, complications occurred in the form of deep infection and avascular necrosis. CONCLUSIONS: Surgical reconstruction of pseudarthrosis of the femoral neck after pyarthrosis of the hip is difficult, but a successful result may be possible in many patients. Every effort should be made to achieve pseudarthrosis repair while the femoral head remains viable on radiographs. Once union is achieved, clinical function and hip stability improve. At early followup, many patients have adequate ROM with minimal pain, an acceptable limp, and are able to do indoor and outdoor activities without support. Long-term results are unknown, and we caution that treating the sequelae of childhood hip disease is challenging. LEVEL OF EVIDENCE: Level IV, therapeutic study.