Surgical evaluation and management of lumbar synovial cysts: the Mayo Clinic experience

Object. The authors report a retrospective analysis of 194 patients surgica lly treated at their institutions for symptomatic lumbar synovial cysts fro m January 1974 to January 1996. Methods. Patient characteristics including age, sex, symptoms, signs, and p reoperative neuroimaging studies were reviewed. Surgical procedures, compli cations, results, and pathological findings were correlated with preoperati ve assessment. One hundred ninety-four patients were surgically treated for symptomatic lumbar synovial cysts. Eighty percent were diagnosed and treat ed between 1987 and 1996. There were 100 men and 94 women with an average a ge of 66 years (range 28-94 years). The most common symptoms were painful r adiculopathy (85%) and neurogenic single or multiroot claudication (44%). H owever, sensory loss (43%) and motor weakness (27%) were also presenting sy mptoms. Eleven percent of patients had undergone previous lumbar surgery pr ior to being referred to the Mayo Clinic. Preoperative neurological examina tion demonstrated motor weakness (40%), sensory loss (45%), reflex changes (57%), and variants of cauda equina syndrome (13%). In 19% of patients, nor mal neurological status was demonstrated. There was equal left/right-sided laterality, and eight patients presented with bilateral synovial cysts. The most commonly affected level was L4-5 (64%). All patients underwent lamine ctomy and resection of the cyst. Concomitant fusion was performed in Is pat ients in whom clinical evidence of instability had been observed. However, subsequent fusion was required in only four patients who developed symptoma tic spondylolisthesis. Surgery-related complications included cerebrospinal fluid leak (three patients), discitis (one patient), epidural hematoma (on e patient), seroma (sone patient), and deep vein thrombosis (one patient). One patient died 3 days after surgery of cardiac dysrhythmia. Follow-up dat a obtained for at least 6 months postoperatively were available in 147 pati ents. Of these, 134 (91%) reported good relief of their pain and 82% experi enced improvement in their motor deficits. Conclusions. Lumbar synovial cysts are a more common cause of lumbar radicu lar pain than previously thought. Surgical removal of the cyst is a safe an d effective treatment for symptomatic relief in patients with lumbar synovi al cysts. A concomitant fusion procedure may be performed in select cases. In this study, only a few patients developed symptomatic spinal instability requiring a second operation.