Abstract
We report a case of lumbar facet cyst. A 71-year-old woman suffered low back pain and left lower extremity pain. MRI revealed intraspinal cyst around the left facet at L5/S1. Conservative therapy was not effective and resection of the cyst was performed. Histologically the cyst did not contain synovial lining cell, and cystic cavity and myxoid change as in the ganglion cyst were not observed. However, it was diagnosed as synovial cyst arising from the facet joint. A synovial cyst and ganglion cyst was found to arise from the juxta-articular region in the spine. It is not clear whether they are two completely separate entities, because the lining of the synovial cyst is often denuded and a series of discontinuity of ganglion cysts from the facet joint by facet arthrography has not been presented. Both synovial and ganglion cysts share a common pathogenesis, being closely associated with degenerative joint disease and rising from the facet joint.
