Osteochondroma - cervical spine

An irregularly shaped ossific mass extends off of the left of C5/C6 both anteriorly and posterior to the vertebral bodies on this side, and appears to involve and enlarge the left intervertebral foramen. The left side of the C5 and C6 vertebral bodies are well defined but remodeled, accommodating the adjacent mass. The margins of the mass are well circumscribed, and the mass does not distort the contour of the tracheal air shadow.

An ossific mass arises from the inferior aspect of the left C5 articular pillar which also has a large non-mineralized soft-tissue component. This lesion creates large, well-defined and well–corticated pressure erosions of the adjacent C5 and C6 vertebral bodies and pedicles on the left. It also involves the left C5 transverse process but does not significantly distort its contour, however it severely distorts the contour of the C6 transverse process, transverse foramen, and articular pillar on the left. The left C5/C6 and C6/C7 intervertebral foramen appear completely occluded by the mass. At the level of C5 the mass extends into the epidural space and narrows the transverse diameter of the central canal to approximately 11 mm.

The lesion is heterogenous in signal intensity, but is predominantly mildly T2 hyperintense compared to muscle, and does not enhance with contrast. The mass causes significant mass effect on the spinal cord at the level of C5 and C6, deviating the thecal sac and cord to the right, obliterating surrounding CSF signal. No associated cord or bone edema signal changes are observed. The left vertebral artery courses anterior and medial to the lesion, with moderate compressive narrowing at the level of the C5/C6 disc space, but maintains normal intraluminal signal flow void cephalad to the mass.

The mass is not metabolically active.

Successful core biopsy.