Outcome of Percutaneous Lumbar Synovial Cyst Rupture in Patients with Lumbar Radiculopathy.

BACKGROUND: Lumbar synovial cysts can result from spondylosis of facet joints. These cysts can encroach on adjacent nerve roots, causing symptoms of radiculopathy. Currently the only definitive treatment for these symptoms is surgery, which may involve laminectomy or laminotomy, with or without spinal fusion. Surgery has been reported to successfully relieve radicular pain in 83.5% of patients by Zhenbo et al. Little information is available concerning the efficacy and outcome of percutaneous fluoroscopic synovial cyst rupture for treatment of facet joint synovial cysts.

OBJECTIVE: The goal of this investigation was to assess the efficacy of fluoroscopically guided lumbar synovial cyst rupture, in particular for its relief of radicular symptoms and its potential to reduce the need for surgical intervention.

STUDY DESIGN: Retrospective evaluation of a case series.

SETTING: University hospital and urban public health care system.

METHODS: With approval from the Institutional Review Board of Case Western Reserve University/ MetroHealth Medical Center, we reviewed the medical charts of patients with lumbar radiculopathy who underwent percutaneous lumbar synovial cyst rupture. The 30 patients in the cohort were treated by one pain specialist between 2006 and 2013. These patients were diagnosed with moderate to severe lower back pain, radiculopathy, and ranged in age from 42 to 80 years. Patients were followed up for a minimum of 6 months and up to 24 months. Pre- and post-procedure pain assessments were reviewed by clinical chart review. In addition post-procedure pain assessments and duration of pain relief were obtained with telephone interviews. Pain had been reported by the patients using a numeric rating scale of 0 - 10 (0 = no pain; 10 = worst possible pain). Charts were reviewed to determine if surgery was eventually performed to correct radicular symptoms.

RESULTS: More than 6 months of pain relief was achieved in 14/30 patients (46%) and between one and 6 months of pain relief was achieved in 7/30 patients (23.3%). Nine patients (30.0%) had recurrence of the synovial cyst requiring repeat rupture and 6 patients (20.0%) required surgical intervention for cyst removal. A Wilcoxon signed-rank test demonstrated that the difference in numeric pain rating scale scores before and after the procedure was statistically significant (P < 0.0001). The average pain reduction was 71.2%. No complications were reported.

LIMITATIONS: The results are limited by the retrospective nature of the data collection and the lack of detailed information regarding patients' functional improvement.

CONCLUSIONS: Rupture of percutaneous lumbar synovial cysts in patients with lumbar radiculopathy was associated with immediate relief of radicular symptoms. In 80% of the patients, synovial cyst rupture eliminated the need for surgical interventions over the measured term. This minimally invasive procedure helps relieve pain in a subset of a patient population associated with these characteristics and is useful for management of this condition. Cyst expansion and failure to rupture with possible neuronal compression are the potential complications of this procedure. This complication did not occur in the study population.

KEY WORDS: Fluoroscopically guided lumbar synovial cyst rupture, lumbar synovial cyst, lumbar zygapophyseal joint cyst, nonsurgical intervention, radiculopathy, spondylosis.