Basioccipital bone osteochondroma growing into the foramen magnum

Osteochondroma is a common bone tumor and rarely affects the central nervous system. Although intraspinal osteochondromas are known to cause neurological deficits, intracranial osteochondromas with neurological compromise are very rare.

The authors report an exceptional case of a quadriparetic 73-year-old patient with a basioccipital bone osteochondroma growing into the foramen magnum. The embryology, differential diagnoses, and optimal management strategies are discussed.

Although extremely rare, osteochondromas should be included in the differential diagnoses of tumors within the foramen magnum. For the tumors originating from the basioccipital bone, a simple medial suboccipital approach might suffice, while for ventral tumors, a far lateral transcondylar approach is necessary to avoid any neurovascular complications. Despite potentially catastrophic presenting symptoms, these tumors are pathologically benign and complete excision often results in long-term cure. To the best of our knowledge, this is the first report of an osteochondroma arising from the basiocciput.