Introduction This study aimed to examine the effects of body mass index (BMI) on functional recovery after total hip arthroplasty (THA).

Materials and methods This prospective case-control study included 269 patients who underwent primary THA. Participants were categorized into normal weight, overweight, and obese groups based on the World Health Organization criteria. Recovery outcomes were assessed across BMI groups using gait measurements and the Japanese Orthopaedic Association (JOA) hip scores.

Results Patients with obesity exhibited slower recovery in walking speed and stride length at 6 months and 1 year than did their less-obese counterparts. At 1 year post-surgery, the JOA hip scores showed no significant differences among the BMI groups, thereby indicating similar satisfaction levels despite initial functional recovery differences.

Conclusions Although patients with obesity faced early recovery challenges, particularly regarding gait, satisfaction with THA outcomes was comparable across all BMI groups at 1 year. These findings highlight the need for personalized management and rehabilitation strategies for optimizing THA outcomes for patients with obesity.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This study was approved by the Medical Ethics Committee of Kanazawa University, Japan (Approval No. 3669, approved on December 11, 2015).

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