Myositis Ossificans Secondary to Lowlying Supracondylar Fracture of the Humerus in a Child: A Case Report

Introduction: Myositis ossificans (MO) is a form of heterotopic ossification that develops within muscles or soft tissues, usually after trauma. It is a benign tumor-like lesion commonly seen in young adults and adolescents, and rarely in children. MO can be classified into two forms: myositis ossificans progressiva (genetic) and myositis ossificans traumatica (acquired). Its exact pathophysiology remains unclear, though trauma is a major contributing factor. Case Presentation: We present a case of a 6-year-old girl who developed MO in her right elbow following a minor trauma caused by a tractor injury. Initial imaging diagnosed a non-displaced supracondylar humerus fracture and she was managed with immobilization. Despite this, she developed persistent pain and stiffness, followed by physiotherapy which worsened her condition. A soft-tissue mass appeared with limited elbow mobility. Radiographic imaging revealed a calcified mass consistent with heterotopic ossification. Due to limited resources and parental refusal, further imaging like MRI was not performed. Conservative management with NSAIDs and rest led to notable improvement over 4 weeks. Discussion: MO is characterized by zonal ossification and typically follows trauma or inappropriate rehabilitation. It commonly affects large skeletal muscles like the quadriceps and brachialis. Diagnosis is often clinical and radiological, with CT being the gold standard. In resource-limited settings, radiography remains a practical alternative. Conclusion: This case underscores the importance of considering MO in cases of post-traumatic stiffness and pain, particularly in children. Conservative treatment can be effective, and physiotherapy should be cautiously approached.