Chondromyxoid fibroma of the sacrum: A case report and literature review

BACKGROUND: Chondromyxoid fibroma (CMF) is an extremely rare, benign cartilaginous tumor that makes up <0.5% of all bone tumors, typically presenting in the second or third decade of life. CMF of the sacrum is exceedingly rare, with only seven documented cases reported in the neurosurgical literature. CASE DESCRIPTION: We report a case of a 35-year-old female with a 3 month history of lower back pain after sustaining a fall on her sacrum/coccyx presenting with a progressive complaint of localized lower back pain, occasional urinary retention without incontinence, gluteal hypesthesia, and pressure below the gluteal crease. Imaging demonstrated a large, expansile enhancing soft-tissue lesion involving the sacrum, distal to the S2-3 disc space. The tumor was removed with partial sacrectomy for open en bloc resection with partial nerve sparing. The patient was found at 1.5-year follow-up with the improvement of symptoms, no recurrence, and no residual neurologic dysfunction. CONCLUSION: Sacral CMF is a rare clinical entity that may mirror more aggressive sacral pathology, including chordoma, in both clinical presentation and imaging characteristics. A review of the available literature regarding diagnosis, surgical management options, and prognosis for sacral CMF is provided.