Lockjaw secondary to skull base osteochondroma: CT findings.

Osteochondromas arising from the long bones, pelvis, or scapulae are common. However, osteochondromas originating from the base of the skull are extremely unusual. Although these tumors are histologically benign, intracranial extension and their close proximity to the cranial nerves may require complex surgery. We present a case in which CT clearly delineated an osteochondroma arising from the base of the skull. The tumor had created a fusion with the ipsilateral coronoid process of the mandible, thus causing lockjaw.