Direct Anterior Approach for Total Hip Arthroplasty in the Elderly with Femoral Neck Fractures: Comparison with Conventional Posterolateral Approach

Background: The aim of this study was to determine if it was feasible and safe to perform total hip arthroplasty (THA) using the direct anterior approach (DAA) when compared with the conventional posterolateral approach (PA) in patients with femoral neck fractures. The time required to start walking was investigated to identify advantages of the muscle-sparing approach. Safety of the approach was judged based on the incidence and nature of all complications. Methods: We retrospectively reviewed 67 THA cases due to femoral neck fractures from October 2015 to January 2019. The PA was used in 31 cases, and the DAA was used in 36 cases. The average operative time and amount of bleeding were evaluated. Cup inclination, anteversion, and leg length discrepancy (LLD) were also measured on radiographs. The time to start walking and complications (e.g., intraoperative fracture, infection, and dislocation) were recorded. Results: The mean operative time was 84.35 +/- 13.95 minutes in PA group and 99.22 +/- 20.33 minutes in DAA group (p = 0.010). But after experiencing 20 cases using the DAA, there was no statistically significant difference in the operative time between the groups. The mean volume of bleeding was 428.73 +/- 207.26 mL in the PA group and 482.47 +/- 150.14 mL in the DAA group. There was no difference in the acetabular cup position between two groups. Ambulation was started at 3.94 days after surgery on average in the PA group and 3.14 days in the DAA group, showing a statistically significant difference. Intraoperative fracture and infection were not observed in either group. The incidence of LLD was 1 in each group. The dislocation rate was 3.2% (1 case) in the PA group and 5.5% (2 cases) in the DAA group. Conclusions: Although the DAA for THA was similar to the PA in terms of operative time, volume of bleeding, and complications, the DAA showed a great advantage in early rehabilitation as a muscle-sparing procedure in the elderly with femoral neck fractures.