[Radicular syndrome and synovial cyst of the zygapophyseal joints: two case-reports]. / Kyste synovial articulaire postérieur lombaire révélé par un syndrome pluriradiculaire: à propos de deux cas.

INTRODUCTION: Multiradicular nerve root compression, and long lasting radicular syndrome occur very often. They happen particularly on degenerative spine. Huge synovial cyst of the zygapophyseal joints may account for it, expand in the epidural area and cause radicular syndrome. EXEGESIS: Two cases of huge synovial cysts spreading into the spinal channel are reported here. Diagnostic and therapeutic modalities are discussed. On degenerative spine, facet joints osteoarthritis may result in synovial cysts. Physical examination findings are radicular syndrome. CONCLUSION: Huge synovial cysts may result in multiple nerve root compression syndrome, as reported in our two cases. Typically, there's no history of preceding trauma and symptoms appear progressively. Magnetic resonance imaging of the spine shows an intra-spinal round mass with typical signal intensity and capsular formation. Treatment consists either in facet joint steroid injection performed with radiologic guidance or in surgical excision.