Costal Osteochondroma

STUDY DESIGN: Report of a rare cause of spinal cord compression: costal osteochondroma. OBJECTIVE: To describe a very rare cause of spinal cord compression, costal osteochondroma, which was present in a 16-year-old girl with a history of hereditary multiple exostoses. SUMMARY OF BACKGROUND DATA: Only four cases of expansion of costal osteochondroma into the spinal canal through an intervertebral foramen have been reported previously. METHODS AND RESULTS: The origin of the osteochondroma at the head of the right 12th rib, the invasion of the spinal canal through the right T12-L1 intervertebral foramen, and the compression of the spinal cord were shown on computed tomography and magnetic resonance imaging. The exact extent of the osteochondroma, particularly the cartilage cap, was delineated accurately by magnetic resonance imaging. Complete excision followed by full recovery occurred 19 months after surgery. CONCLUSION: Magnetic resonance imaging is the preferred method of investigation in cases of osteochondroma related to spine, because it allows for better pre-operative planning and helps to prevent incomplete excision of the tumor.