Spinal synovial cysts: clinical and therapeutic considerations.

Objective: Synovial cysts are an important differential diagnosis in lumbar radiculopathy.

Patients and methods: From 2000 to 2005, we treated 32 patients (22 female, 10 male) suffering from lumbar radiculopathy due to spinal synovial cysts. The mean age was 64 years (range 42-84). The clinical mix of cases at admission was: 10 patients with radiculating pain accompanied by sensory disturbances, 8 with neurogenic claudication, 7 with muscular weakness, 6 with radicular pain, and one with back pain only. The anatomical distribution was 10 cases at the L5/S1 level, 16 cases at L4/5, 5 cases at L3/4, and one case at L1/2. The average period from the first onset of symptoms to treatment was 9 months. Twenty-five cases were treated via a (limited) laminotomy only and 7 via hemilaminectomy. The cases were evaluated clinically at routine follow-up.

Results: After a follow-up of between six months and three years, 15 patients were free of complaints, 13 had improved markedly, while 3 had considerable remaining complaints. One patient developed an instability requiring spinal fusion. We observed a local recurrence at the same site in one patient and three cases of synovial cysts on the contralateral joint at the same spinal level.

Conclusion: The operative removal of a spinal synovial cyst is beneficial in terms of treatment of the nerve root compression. In the majority of cases, a (limited) laminotomy is sufficient as an approach.