Comparison of Decompression With and Without Fusion for Patients With Synovial Facet Cysts.

STUDY

DESIGN

This is a retrospective study.

OBJECTIVE

To compare (1) recurrence of radiculopathy and (2) back pain after decompression with and without fusion for patients with a symptomatic synovial cyst.

BACKGROUND

Previous work described favorable outcomes following cyst excision with and without fusion. Because of the association of facet cysts with spinal instability it is hypothesized that a decompression with fusion will lead to better outcomes. However, previous studies present contradicting results.

METHODS

We included 314 consecutive patients that underwent operative treatment for a facet cyst between 2003 and 2013 at 2 tertiary spine referral centers: 224 (71%) underwent decompression without fusion (35% spondylolisthesis), 90 (29%) underwent decompression with fusion (63% spondylolisthesis). Baseline data were compared between the groups. Bivariate log-rank analysis was used to compare outcomes between groups, followed by multivariable Cox regression analysis accounting for differences in baseline characteristics.

RESULTS

Patients undergoing decompression with fusion presented with a higher incidence of back pain (P=0.004) and spondylolisthesis (P<0.001), had more often bilateral decompressions (P<0.001), more facetectomies (P<0.001), and more levels of decompression (P=0.004) than those who underwent decompression alone. We found a difference in recurrence of radiculopathy (no fusion: 25% vs. fusion: 9.4%, P=0.029) in bivariate analysis. However, this difference did not hold when accounting for confounders (hazard ratio, 0.50, 95% confidence interval, 0.19-1.31, P=0.16). There was no difference in recurrence of back pain in bivariate (no fusion: 29% vs. fusion: 22%, P=0.51) and multivariable analysis (hazard ratio 0.51, 95% confidence interval, 0.23-1.14, P=0.10).

CONCLUSIONS

We found, with the numbers evaluated, no difference in recurrence of radiculopathy or back pain between patients undergoing decompression with or without fusion after accounting for confounders. The decision for fusion should be considered in light of the extent of decompression and the existence of other pathology.

LEVEL OF EVIDENCE: Level III-therapeutic study.