Plantar Myositis Ossificans: A Rare Case Report and Review of the Literature

Abstract

Myositis ossificans (MO) is a benign heterotopic ossification process that most commonly affects large skeletal muscles and typically develops within 2–12 weeks following trauma. Non-traumatic forms and atypical localizations are uncommon and may represent a diagnostic challenge. Plantar involvement is particularly rare and may closely mimic malignant soft tissue tumors.We report a rare case of long-standing plantar myositis ossificans of the heel in a 45-year-old man presenting with a slowly progressive mass evolving over a 12-year period and associated with progressive functional impairment. This case highlights the diagnostic difficulties encountered in atypical presentations of myositis ossificans, the limitations of biopsy in such settings, and the contribution of magnetic resonance imaging to lesion assessment. A focused review of the literature is also provided, with particular emphasis on differential diagnoses, imaging characteristics, and the diagnostic and therapeutic role of complete surgical excision.