Forty adults with hip osteoarthritis undergoing total hip arthroplasty through the modified Hardinge approach were randomized to receive intraoperative platelet-rich plasma injection (n=19) or placebo saline injection (n=21). The primary outcome of interest was MRI-assessed healing of the gluteus medius and minimus, including tendon tears, atrophy, fatty degeneration, and fluid collections. Secondary outcomes included heterotopic ossification, periprosthetic findings, and postoperative complications. Outcomes were assessed at three and twelve months postoperatively. Overall, the results revealed no significant between-group differences in gluteal tendon tears, atrophy, fatty atrophy, or fluid collections at either time point. PRP did not demonstrate radiological benefit, suggesting no role for its routine use for gluteal muscle healing in Hardinge-approach THA.