[Minimally invasive resection of spinal synovial cysts: Technical note]

To present the treatment algorithm, surgical technique, and results of a series of patients with spinal synovial cysts operated with minimally invasive techniques (MIS).

Spinal synovial cysts originate from the dilation and potential rupture of the synovial sheath of a facet joint. Surgical resection is considered the treatment of choice in symptomatic patients. The use of MIS techniques could reduce the disruption of the facet joint involved, reducing the risk of postoperative instability.

We retrospectively evaluated 21 patients with spinal synovial cysts operated by MIS approach and decompression. We analyzed the signs, symptoms, surgical time, hospital stay, evolution, and complications. The visual analog scale (VAS) was used to evaluate pain and the Weiner scale and the modified Macnab criteria to measure the patient's postoperative satisfaction.

A total of 21 patients were surgically treated with MIS technique; 76.2% (n = 16) did not require arthrodesis, the remaining 23.8% (n = 5) were fused. We performed 13 (61.9%) contralateral hemilaminectomies, 7 ipsilateral hemilaminectomies (33.3%), and 1 laminectomy in S1-S2. The average follow-up was 26 months; surgical time was 150.33 ± 63.31 min, with a hospital stay of 2.5 ± 1.78 days. The VAS decreased from 8.3 preoperatively to 2.3 postoperatively. Sixteen patients reported excellent results, four good and one regular in the scale of Macnab. 95.2% of patients perceived that the procedure was very/quite successful according to the Weiner scale.

The minimally invasive approach is a safe and effective procedure for the complete resection of spinal synovial cysts. It provides excellent clinical-functional results by preserving muscles, ligaments, and joint facets.