Decompression with instrumented fusion is the most commonly recommended surgical procedure for treating the symptoms of isthmic spondylolisthesis. A less intrusive traditional method, consisting solely of decompression, has also been recorded. In this study, the authors examined the clinical outcomes of decompression alone with decompression combined with instrumented fusion in patients with isthmic spondylolisthesis.
Decompression alone (n = 43) or decompression with instrumented fusion (n = 41) were given to 84 patients with lumbar radiculopathy due to low-grade isthmic spondylolisthesis. The primary outcome measures were the Roland Disability Questionnaire (RDQ) scores, distinct visual analog scales (VASs) for back and leg pain, and patient reports of felt improvement at 12-week (p = 0.32, 95% CI −4.02 to 1.34) and 2-year follow-ups (10.3, 95% CI 3.9–8.2, vs 6.0, 95% CI 8.2–12.4; p = 0.006, 95% CI −7.3 to −1.3). An additional outcome measure was the proportion of reoperations. The researchers used a repeated-measures ANOVA with the intention-to-treat concept. On a 100-mm VAS scale, back pain decreased more in the fusion group (difference: −18.3 mm, CI −32.1 to −4.4, p = 0.01), and a higher percentage of patients said recovery was “excellent” (44% vs 74%, p = 0.01). At the 2-year follow-up, the decompression group had a 47% chance of reoperation while the fusion group had a 13% chance (p< 0.001).
Decompression combined with instrumented fusion produced similar short-term results, much better long-term outcomes, and fewer reoperations in patients with isthmic spondylolisthesis than decompression alone. Decompression with instrumented fusion is a superior surgical method that should be considered first for isthmic spondylolisthesis but not for degenerative spondylolisthesis, which has a distinct etiology.