A prospective randomised comparison of earlier function after total hip arthroplasty with a mini posterior approach or supercapsular percutaneously-assisted total hip approach: a gait analysis study

Background: The supercapsular percutaneously-assisted total hip (SuperPATH) approach is a muscle sparing surgical technique for total hip arthroplasty (THA). The literature reports good clinical and functional results of the SuperPATH technique in the short term. We aimed to compare early outcomes and gait analysis of THA using the mini posterior approach (MPA) and supercapsular percutaneously-assisted total hip (SuperPATH) approach. Methods: 44 patients who underwent THA, were randomly allocated to either MPA or SuperPATH. The data were then collected prospectively (preoperatively and postoperatively at 6 weeks). Plain anteroposterior radiographs of the pelvis and instrumental gait analysis were obtained. The visual analogue scale (VAS), Harris Hip Score (HHS) and Hip disability and Osteoarthritis Outcome Scores (HOOS) were used to assess functional and clinical outcomes. Results: No significant difference was found in patients' surgical outcomes. Patients in the SuperPATH group had less pain according to the VAS score at follow-up than the MPA group (p < 0.01). There was also a significant improvement in HHS and HOOS scores for all patients (p < 0.001) with the SuperPATH group showing superior changes. The comparison of mean differences in gait velocity between preoperative and 6 weeks postoperative result, revealed improvement in the SuperPATH group over the MPA group (p = 0.06). Limping was more persistent in the MPA group. Kinematic parameters demonstrated improved hip joint excursion slightly higher in the MPA group. There was no significant improvement in kinetic and kinematic parameters at different walking moments for all patients at 6 weeks compared to preoperative gait patterns. Conclusions: SuperPATH and MPA both show excellent results. This study reveals that the SuperPATH technique was associated with lower postoperative pain levels, and higher physical function and quality of life. Improved functional outcomes allowed earlier postoperative rehabilitation and faster recovery. Specific improvement in gait patterns were identified with nonsignificant differences between the 2 approaches at 6 weeks follow-up.