In laminectomies for costal osteochondroma causing spinal cord compression, visualization of the extraforaminal part of the tumor is limited. The authors describe using a costotransversectomy to resolve spinal cord compression by a costal osteochondroma invading through the neural foramen. A 21-year-old woman with hereditary multiple exostoses presented with hand numbness and progressive neck and upper back pain. Plain radiographs identified a large lesion of the T2 and T3 pedicles, with encroachment on the T2-3 neural foramen causing similar to 50% spinal canal stenosis. Costotransversectomy was performed to resect the cartilaginous portions of the osteochondroma, debulk the mass, and decompress the spinal canal. A mass of mature bone was left, but no appreciable cartilaginous tumor. At five-year follow-up, the patient had improvement of neck pain, no new neurological deficits. a stable residual mass, and no new osteochondromas, indicating that appropriate surgical management can yield good results and no evidence of recurrence.
