Reasons for Failure of Primary Total Hip Arthroplasty Performed Through a Direct Anterior Approach.

The direct anterior approach (DAA) for total hip arthroplasty (THA) is a technique popular among some arthroplasty surgeons. There is currently a paucity of data regarding reasons for failure of THA using the DAA. The authors conducted a retrospective review of prospectively collected data on 56 patients who underwent revision THA at their institution after failing primary THA that was performed through a DAA either at their institution (n=8) or elsewhere (n=48) from January 1, 2010, to June 1, 2017. Patients were grouped by modes of failure and compared using patient characteristics, surgical factors, and radiographic outcomes. Total hip arthroplasties performed through the DAA failed due to infection in 21 (38%) patients, aseptic/mechanical loosening in 14 (25%) patients, intraoperative fracture in 6 (11%) patients, postoperative fracture in 6 (11%) patients, tendinitis or pain of unknown etiology in 3 (5%) patients, metallosis in 3 (5%) patients, instability/dislocation in 2 (4%) patients, and leg length discrepancy in 1 (2%) patient. Patients who underwent revision due to unrecognized intraoperative fracture had a lower body mass index (BMI) and weight than patients who had failure due to postoperative fracture, aseptic loosening, or infection. The 4 most common modes of failure included infection, aseptic loosening, unrecognized intraoperative fracture, and postoperative fracture. Together, these made up 84% of failed DAA THAs. Patients with a lower BMI are more likely to have failure due to intraoperative fractures. Patients with a higher BMI are more likely to have failure due to postoperative fracture, aseptic loosening, or infection. [Orthopedics. 2020;43(4);239-244.].