Intraspinal synovial cysts: natural history and diagnosis by CT.

Abstract

Synovial cysts rarely have been recognized in the [human] spinal canal. In 1 subsequently proved case, and in 3 other unproved cases presently reported, computed tomography (CT) showed the synovial cyst as an encapsulated cystic structure that was adjacent to a degenerated L4-5 facet joint. Although a synovial cyst may clincally simulate a herniated disk or an intraspinal tumor at myelography, it can be identified reliably by CT, and exploratory laminectomy may be prevented.