Acute sciatica and progressive neurological deficit secondary to facet synovial cysts: A report of two cases.

OBJECTIVE To describe two patients with lumbar facet synovial cysts causing sciatica and progressive neurological deficit. CLINICAL FEATURES A 52-year-old female with bilateral sciatica and a neurological deficit that progressed to a foot drop; and a 54-year-old female with worsening sciatica and progressive calf weakness were seen at a major tertiary care centre. Diagnostic imaging studies revealed the presence of spinal nerve root impingement by large facet synovial cysts. INTERVENTIONS AND OUTCOMES Activity modification, gabapentinoid and non-steroidal anti-inflammatory medications were unsuccessful in ameliorating either patient's symptoms. One patient had been receiving ongoing lumbar chiropractic spinal manipulative therapy despite the onset of a progressive neurological deficit. Both patients eventually required surgery to remove the cyst and decompress the affected spinal nerve roots. CONCLUSION Patients with acute sciatica who develop a progressive neurological deficit while under care, require prompt referral for axial imaging and surgical consultation. Primary care spine clinicians need to be aware of lumbar facet synovial cysts as a possible cause of acute sciatica and the associated increased risk of the patient developing a progressive neurological deficit.