Incomplete resection of lumbar synovial cysts – Evaluating the risk of recurrence

Synovial cysts are generally located in the lumbar spine adjacent to facet joints. Most studies recommend surgical resection. Adhesions of the lumbar synovial cyst to the dura are common and can result in dural tears with subsequent CSF fistula or nerve injury. The recurrence rate after incomplete resection of lumbar synovial cysts is unclear. For this purpose, we report on our experience of 148 patients who underwent synovial cyst resection from 2000 to 2011.

We reviewed records of patients who underwent microsurgical resection of symptomatic lumbar synovial cysts between 2000 and 2011 with a minimum one-year follow-up to identify cases with incomplete synovial cyst resection. Patient and surgical reports were retrospectively evaluated regarding extent of cyst resection, dural tears and surgery-related complications. Patients were asked to complete questionnaires regarding their clinical outcome and to report on further lumbar operations.

We identified 148 patients with lumbar synovial cysts who were surgically treated in our department. In 8 patients (5.4%), the synovial cysts were not resected completely due to dural adhesions and high risk for dural tears. Sufficient decompression was achieved in all patients. Seven of these patients were pleased with the results of the operation and would undergo surgery again. The remaining patient suffered from a facet joint syndrome, which was successfully treated conservatively, without evidence of a recurrent synovial cyst in the MRI.

Only in case of severe adhesions to the dura complete resection was not enforced to avoid dural tears. In none of the 8 patients symptomatic recurrence of synovial cysts occurred. Aware of the limited numbers, we suggest rather leaving remnants of an attached synovial cyst behind after a sufficient decompression than risking dural tears and surgery-related complications. This trial is registered with DRKS00006133.