Surgical Management of Spinal Synovial Cysts: A Series of 23 Patients and Systematic Analysis of the Literature.

Study Design: Retrospective cohort and review of the literature.
Objective: To compare surgical strategies for the management of spinal synovial cysts.
Summary of Background Data: The recent multiplication of retrospective series of patients with spinal synovial cysts has led to a reappraisal of their incidence and clinical significance. Although surgery is considered the treatment of choice, there is still no agreement over which surgical technique should be used.
Methods: We retrospectively reviewed 23 consecutive patients undergoing surgery for a spinal synovial cyst in our department between 2004 and 2010. Surgical procedures were classified into the following 4 categories: cystectomy by an interlaminar approach, hemilaminectomy, laminectomy, or associated with instrumented spinal fusion. Clinical outcome, cyst recurrence, need for subsequent fusion, and perioperative complications were compared between these groups.
Results: Of the patients included in the present cohort, 11 underwent cyst excision by an interlaminar approach, 8 had a hemilaminectomy, 2 had a laminectomy, and 2 underwent instrumented fusion. "Excellent" or "good" clinical outcome on the Macnab modified scale were achieved for 16 patients (69.6%), and there were 2 perioperative complications, 2 cyst recurrences, and 1 secondary fusion. Of the 519 patients reported in the literature, overall clinical outcome was either "excellent" or "good" for 83% of all patients. However, unfavorable outcome was more likely in patients treated with decompression alone (80/396) than decompression with fusion (10/123) (20.2% vs. 8.1%; P=0.003) and cyst recurrence (13/396 vs. 0/123; P=0.028). In contrast, the rate of perioperative complications was significantly higher in the fusion group (23/123) compared with decompression alone (11/396) (18.7% vs. 2.8%; P<0.0001).
Conclusions: In patients with spinal synovial cyst, spinal fusion seems to decrease the risk of unfavorable clinical outcome and cyst recurrence and associated with a considerably higher rate of perioperative complications.