Synovial cyst at the intervertebral foramina causing lumbar radiculopathy

Objective: To determine the presence of intraforaminal synovial cysts resulting in nerve root compression. Methods: 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. Results: At surgery there was a cystic mass pressing on the nerve root, and no connection or communication with the dural structures could be found. Conclusion: 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.