Percutaneous Endoscopic Lumbar Surgery via the Transfacet Approach for Lumbar Synovial Cyst

Background There are currently no high-quality studies on the optimal therapeutic approach for juxtafacet cyst, as treatment guidelines have not been developed. Herein, a novel technique in which we used an endoscopic transfacet approach to treat a patient with symptomatic lumbar synovial cyst is presented. Case Description An 87-year-old man presented with severe dull pain in the right anterior thigh. Lumbar magnetic resonance imaging revealed disc extrusion over the central canal zone at the L2–L3 and L4–L5 levels and an ovoid lesion with a hyperintense center plus a hypointense rim on the T2-weighted image. The lesion was located over the medial side of the right juxtafacet region at the L2–L3 level, causing thecal sac compression. After the operation, the visual analog pain scale improved with a value of 0–1/10, and straight leg raise test was negative. Microscopically, cystic fibrous tissue with focal myxoid degeneration, fibrin exudate, and scant synovial-like lining was observed. These findings were consistent with clinical synovial cyst. Three months later, lumbar magnetic resonance imaging was performed, and no evidence of cyst was disclosed. Lumbar computed tomography revealed the upper part of left L2–L3 facet joint was removed. The patient did not report any radicular pain during the 6-month follow-up period. Conclusions Percutaneous endoscopic lumbar surgery could be a new option for the management of lumbar synovial cysts, especially when general anesthesia is not appropriate for the patient.