[en] OBJECT: A consecutive series of 28 "operated" juxtafacet cysts is reported. We emphasize the clinical and radiological aspects leading to diagnosis. We also discuss the results of the surgical treatment. MATERIAL AND METHODS: Medical information and radiological studies involving 28 patients were analyzed. Each patient has been operated on by decompressive laminectomy and resection of the cyst. The diagnosis was always confirmed by a pathological examination. The cyst most frequently occurred at the L4-L5 level (n = 18), and seldom at the L5-S1 (n - 6) or L3-L4 (n - 4) levels. RESULTS: The differential diagnosis from other pathological causes responsible for a radicular compression could not be done by physical examination. Spine X-rays or myelogram were nonspecific. Computed Tomography or CT-myelography could help in the diagnosis but MR imaging was the most sensitive. In our series, the respective sensitivities of these techniques are 56, 42 and 77%. The preoperative diagnosis was correct in 18 patients (64%). The cyst was sometimes adherent to the underlying dura, then significantly increasing the risk of dural tear and spinal fluid leak, especially when located at L3-L4 level. Surgical ablation lead to a complete recovery or an important improvement in 26 patients. CONCLUSIONS: The diagnosis of the juxtafacet cyst of the lumbar spine is better achieved by MRI. Surgery is the gold standard treatment, safe and long-term effective. When a total cyst removal with an internal facetectomy are performed, recurrence is exceptional.