Ossified intramuscular hematoma of the paraspinal muscles: a case report

BACKGROUND: Ossified intramuscular hematomas (OIH) are an exceptionally rare condition that may be mistaken for alternative calcified intramuscular pathologies, such as myositis ossificans. Exceedingly few cases of OIHs have been reported to date, with no cases yet to be reported in the paraspinal muscles. CASE PRESENTATION: Here, we report on a patient who presented with a chronic back pain and swelling in the setting of trauma 15 years prior. Radiographic workup revealed a calcified mass in the erector spinae muscles. The lesion was surgically excised, and histologic examination confirmed the presence of an OIH. The patient did well postoperatively. CONCLUSION: An OIH is a poorly understood pathology. Although benign, these lesions can cause significant morbidity, and surgical excision is a reasonable and safe treatment option. OIHs may be distinguished from related calcified intramuscular pathologies based on key clinical features and distinct histopathology. Clinically, they are characterized by a history of remote trauma and, on histopathology, by compact, mature bone in the setting of an old, organizing hematoma. Despite this, similarities with other calcified intramuscular pathologies persist, and further study is warranted to better understand and classify these lesions.