Does the anterior approach for total hip arthroplasty better restore stair climbing gait mechanics?

While total hip arthroplasty (THA) provides pain relief and restores mobility, gait anomalies persist even years after surgery. A muscle sparing surgical approach could result in better postoperative gait mechanics. Our purpose was to compare both the anterior muscle sparing approach and the direct lateral approach (LAT) to a matched control group by using three-dimensional motion analysis while performing stair ascent and descent tasks. Lower-limb kinematics and kinetics were recorded for 20 patients that had an anterior approach (ANT), 20 that had a LAT, and 20 age- and weight-matched control participants. Patients were assessed on average 10 months after surgery. Compared to the control group, during stair ascent, the anterior group had reduced peak hip extension, peak hip flexion moment, and peak hip power. The lateral group had reduced peak hip abduction, hip frontal plane range of motion, and peak hip internal rotation. In stair descent, the anterior group had reduced peak hip flexion, peak hip abduction moment and internal rotation, as well as peak hip power. The lateral group had reduced peak hip flexion, peak knee extension moment, and peak hip power. Therefore, gait anomalies persist after THA for both approaches, which could be due to other factors such as preoperative gait adaptations.