Safe and accurate: learning the direct anterior total hip arthroplasty

Wear, instability, leg length, and muscle recovery are the major obstacles in total hip arthroplasty (THA). The direct anterior approach with fluoroscopic assistance has been proposed to address all four of these issues. The goal of this study was to assess the learning curve, safety, and accuracy of direct anterior THA. A retrospective review was completed on a single surgeon's initial consecutive series of 300 THAs performed via a direct anterior approach. Cases were grouped based on chronologic order (1-100, 101-200, 201-300). Operative time, fluoroscopy time, estimated blood loss, radiographic leg length discrepancy (LLD), radiographic cup abduction angle, and complications were recorded. Data were analyzed using an analysis of variance. Postoperatively, all patients were managed without dislocation precautions. The average age for the cohort was 58.9 years, and the average BMI was 29. All groups were similar with respect to age and BMI. Direct anterior THA demonstrated significant reductions inoperative and fluoroscopy after the first 100 cases. Mean surgery time was 132.8 minutes for group 1, 109.9 for group 2, and 106.1 for group 3 (P<.001). Mean fluoroscopy time was 32.1 seconds for group 1, 14.5 for group 2, and 14.5 for group 3 (P<.001). There was one dislocation in group 3 and three intraoperative calcar fractures in the first 100 cases. There were no infections. Direct anterior THA demonstrated a reduction in operative time and fluoroscopy time after the initial 100 cases. Calcar fracture did not occur after the first 62 cases. Cup abduction angle, dislocation rate, and LLD were excellent in all groups.