There is high quality evidence showing that there is no difference in terms of functionality after decompression alone compared to decompression with fusion in patients with degenerative lumbar spondylolisthesis at two years of follow-up. This is the key takeaway of a systematic review and meta-analysis, published recently in the European Spine Journal by Pravesh Gadjradj (Weill Cornell, Brain and Spine Centre, New York, USA) et al.
The researchers believe that further studies should focus on long-term comparative outcomes, health economic evaluations, and identifying those patients that may benefit more from decompression with fusion instead of decompression alone.
According to Gadjradj et al, while surgical decompression is standard care in the treatment of degenerative spondylolisthesis in patients with symptomatic lumbar spinal stenosis, “there remains controversy over the benefits of adding fusion”. In addition, “the persistent lack of consensus on this matter and the availability of new data warrants a contemporary systematic review and meta-analysis of the literature”.
A range of online databases were systematically searched up to October 2022 for randomised controlled trials (RCTs) and prospective studies comparing outcomes of decompression alone versus decompression with fusion for lumbar spinal stenosis in patients with degenerative spondylolisthesis.
The primary outcome was the Oswestry Disability Index and secondary outcomes included leg and back pain, surgical outcomes, and radiological outcomes. Pooled effect estimates were calculated and presented as mean differences (MD) with their 95% confidence intervals (CI) at two-year follow-up.
Of the 2,403 studies identified, a total of five RCTs and two prospective studies were included. Overall, most studies had a low or unclear risk of selection bias and most studies were focused on low grade degenerative spondylolisthesis. All patient-reported outcomes showed low statistical heterogeneity.
Overall, there was high-quality evidence suggesting no difference in functionality at two years of follow-up (MD −0.31, 95% CI −3.81 to 3.19). Furthermore, there was high-quality evidence of no difference in leg pain (MD −1.79, 95% CI −5.08 to 1.5) or back pain (MD −2.54, 95% CI −6.76 to 1.67) between patients undergoing decompression vs. decompression with fusion.
Pooled surgical outcomes showed less blood loss after decompression only, shorter length of hospital stay, and a similar reoperation rate compared to decompression with fusion.
Speaking to Spinal News International, Gadjradj said: “The added value of fusion in addition to lumbar decompression for degenerative spondylolisthesis has been controversial for a few decades. After publication of two highly cited randomised controlled trials in 2016, this controversy persisted, and no clear consensus could be found among spine surgeons. Fortunately, much novel research has been published on this subject throughout the last years. Therefore, we were interested to see if pooling these data would allow us to make some firmer recommendations for clinical practice.
“Based on the published data, we could not find any evidence for added value of fusion to decompression alone for degenerative spondylolisthesis; patient-reported outcome measures are similar, but risk of complications and costs are higher. So we would recommend spine surgeons to be more conservative in offering concomitant fusion to patients with degenerative spondylolisthesis.”