Ossification of the posterior longitudinal ligament mimicking cord compression from a dorsal disc protrusion: a...

A patient with focal anterior compression of the dorsal cord at the level of the D6/7 disc was mistakenly diagnosed as a dorsal disc protrusion on the basis of CT myelography. The CT scanning had been confined to axial views at the level of the cord compression. A transthoracic exploration failed to reveal a disc protrusion and the correct diagnosis, ossification of the posterior longitudinal ligament, was only revealed by a subsequent sagittal CT scan. This case emphasizes the dangers of relying on limited axial imaging in diagnosing a spinal lesion.