ABSTRACT Background Chronic expanding hematoma is defined as a progressively enlarging soft tissue mass persisting beyond 1 month, typically resulting from prior trauma or surgical procedures. Although the condition is rare, its occurrence within deep musculature—particularly with bilateral involvement of the gluteus maximus—is exceedingly uncommon. No previously published English‐language reports were identified describing bilateral gluteus maximus hematomas associated with gluteal muscle contracture (GMC). Case Report This report describes a 29‐year‐old male presenting with bilateral chronic expanding hematomas involving the gluteus maximus muscles, accompanied by clinical features consistent with GMC. Conclusion Chronic expanding hematoma should be considered a potential underlying etiology in individuals presenting with GMC, particularly when involving deep gluteal musculature.
Pan et al. (2026) studied this question.