Simple microsurgical extirpation as a method of choice in treating symptomatic spinal facet joint cysts, a retrospective case series.

BACKGROUND: Facet joint cysts (FJCs) are a cause of radiculopathy, back pain, cauda equina syndrome, or claudication. They mostly affect the lumbar spine in the elderly, prevailing in women, and are connected to spinal degeneration and instability. We aimed to evaluate the safety and efficacy of open surgical decompression and cyst excision without a subsequent fusion.

METHODS: We evaluated neurologic symptoms and potential signs of spinal instability on preoperative vs postoperative radiological examination. We performed a histological assessment of the extirpated cysts. Statistical analysis was then performed.

RESULTS: Forty-four patients (out of total 66) were included. Average age was 61.2 years. Female patients prevailed (61.4%). Mean follow-up was 5.3 years. The segment most frequently affected by FJCs was L4/5 (65.9%). Resection of the cyst led to significant relief from neurological symptoms in most cases. Thus, 95.5% of patients reported their postoperative outcome as excellent. Pre-operation, 43.2% and 47.4% patients demonstrated radiographic signs of instability on an MRI scan and signs of spondylolisthesis on a dynamic X-ray scan in the operated segment, respectively, with 54.5% manifesting signs of spondylolisthesis in the same segment on a postoperative dynamic X-ray scan. Despite spondylolisthesis progression, zero patients required reoperation. Histologically, pseudocysts without synovium were more frequent than synovial cysts.

CONCLUSIONS: Simple FJC extirpation is a safe and effective method for resolving radicular symptoms, with excellent long-term outcomes. It does not lead to the development of a clinically significant spondylolisthesis in the operated segment, and thus no supplementary fusion with instrumented stabilisation is required.