Synovial cyst at the intervertebral foramina causing lumbar radiculopathy.

Abstract

To determine the presence of intraforaminal synovial cysts resulting in nerve root compression. A 26 year old man presenting with left leg pain was admitted. He had no motor, sensory, or reflex changes. Magnetic resonance imaging (MRI) and MRI-myelography showed an intra and extra foraminal, extradural, cystic lesion at L4 vertebra on the left side. At surgery there was a cystic mass pressing on the nerve root, and no connection or communication with the dural structures could be found. Synovial cysts are uncommon extradural degenerative lesions. Intraspinal synovial cysts occur most often at the L4-5 level, but they have been reported in all areas of the spine except the intraforaminal region and the sacrum.