Does Simultaneous Fusion of Preexisting Spinal Canal Stenosis Adjacent to Lumbar Degenerative Spondylolisthesis Achieve a Better Clinical Outcome? A Retrospective Study with More than 5-year Follow-Up.

BACKGROUND:  In this study, we investigate the effect of simultaneous fusion of preexisting adjacent spinal canal stenosis on the outcome of patients with lumbar spondylolisthesis.

METHODS:  Patients with lumbar spondylolisthesis who underwent transforaminal lumbar interbody fusion (TLIF) from August 2013 to March 2016 were included. The inclusion criteria were the following: single-level spondylolisthesis (L4 or L5) and mild to moderate spinal stenosis at cranial adjacent segment of the spondylolisthesis segment before operation. According to whether the adjacent stenotic segment was included in the scope of surgery, the patients were divided into two groups: group A, only the spondylolisthesis was treated with single-level TLIF, and the adjacent stenosis was not treated with any surgery; In group B, TLIF were performed in the spondylolisthesis segment and the adjacent stenotic level; no spinal stenosis was found in other levels. The patients were followed up for more than 5 years. The general information before operation, visual analog scale (VAS) scores of low back pain and leg pain, and Oswestry disability index (ODI) scores before operation and at the last follow-up were recorded.

RESULTS:  A total of 23 patients were included in group A, and 24 patients were included in group B. There was no significant difference between the two groups in gender distribution, age, course of disease, level of slippage, length of stay, degree of spondylolisthesis, stenotic grade of adjacent segment, and intervertebral disk degeneration grade ( p > 0.05). The blood loss during surgery in group B was significantly higher than that in group A ( p < 0.05). The operation time of group B was longer than that of group A, but the difference was not statistically significant ( p  = 0.245). There was no significant difference in preoperative VAS and ODI scores between the two groups. At the last follow-up, the VAS scores of low back pain in the two groups were almost the same. However, the VAS scores of leg pain and ODI scores in group B were slightly higher than those in group A at the last follow-up, but the difference was not statistically significant ( p > 0.05). If relatives and friends have the similar disease, all the patients of group A and 87.5% of patients in group B would recommend that type of surgery. The satisfaction of group A (100%) was higher than that of group B (79.17%), but the difference was not statistically significant ( p  = 0.068).

CONCLUSIONS:  For single-level lumbar spondylolisthesis with mild to moderate spinal stenosis in adjacent segment before operation, decompression and fusion on the level of spondylolisthesis only is a safe, less invasive, and economical surgical option, with good long-term clinical efficacy and high satisfaction rates.