Salvage of Failed Femoral Neck Fracture Fixation with Conversion Total Hip Arthroplasty Using the Direct Anterior Approach

PURPOSE: Failed femoral neck fracture (FNF) fixation with in situ pinning presents a surgical challenge. Osteoporotic bone, retained hardware, and a typically elderly population magnify the risks of surgery. Here, outcomes of conversion total hip arthroplasty (THA) using two separate incisions in these high-risk patients were examined. MATERIALS AND METHODS: Medical records for 42 patients with a prior history of FNF fixation who underwent conversion THA with hardware removal between 2009 and 2019 were retrospectively reviewed. Surgery was performed by a single surgeon at a single institution. All patients underwent hardware removal followed by direct anterior approach (DAA) THA using two separate incisions. Clinical outcomes, radiographic findings, and perioperative morbidity and mortality are reported. RESULTS: Clinically, there were no postoperative dislocations, periprosthetic fractures, or infections at follow-up. After a mean follow-up of 4 years, the mean hip disability and osteoarthritis outcome score, junior (HOOS, Jr) was 91. Radiographically, the mean postoperative cup abduction was 44 degrees and the mean cup anteversion was 21 degrees with an improvement in preoperative leg length discrepancy. Perioperative complications included one case of immediate foot drop and two readmissions for medical issues. One patient died one month after conversion THA. CONCLUSION: Salvage of failed FNF treatment may be managed with conversion THA and DAA with a separate incision for hardware removal. Preservation of posterior soft tissues using a DAA and intraoperative fluoroscopy may mitigate well-known complications related to fracture and dislocation. While favorable clinical outcomes are possible, salvage surgery is still not without substantial surgical and medical risks.