Hip muscle power recovery after hip replacement using anterior-based muscle-sparing approach in elderly femoral neck fracture: a prospective study in 40 patients

The early rehabilitation and mobilization after hip arthroplasty (HA) in elderly femoral neck fracture (FNF) patients significantly reduces the postoperative morbidity and mortality. The direct anterior approach (DAA) without the muscle detachment has been shown to improve the early postoperative functional outcomes in coxarthrosis patients. However, the application of DAA on elderly FNF and the most suitable surgical technique have rarely been investigated. This study aimed to report the short-term outcome after our anterior-based muscle-sparing approach (ABMS) in elderly FNF. A prospective study, in 40 elderly unilateral FNF patients who underwent HA with ABMS, was conducted. The primary outcomes were hip flexion and abduction power at each follow-up period. The contralateral muscle power, measured at 3 and 6 months, was used as the control value. The perioperative data and complications were recorded. Thirty-two patients underwent bipolar hemiarthroplasty (BHA), while eight other patients received total hip arthroplasty (THA). The hip abduction power returned to control value at 6 weeks (99.0% 6.1%; 95% CI: 86.1-111.8). The hip flexion power returned to control at 3 months (108.5% 5.6%, 95% CI: 96.8-120.2). No iatrogenic nerve injury was found. The intraoperative femoral fracture (IFF) was found in 7 patients (17.5%), and was significantly related to the early period of learning skill (first 11 cases;