Effectiveness of decompression alone versus decompression plus fusion for lumbar spinal stenosis: a systematic review and meta-analysis

The debate on efficacy of fusion added to decompression for lumbar spinal stenosis (LSS) is ongoing. No meta-analysis has compared the effectiveness of decompression versus decompression plus fusion in treating patients with LSS. A literature search was performed in the Web of Science, PubMed, Embase, and Springer databases from 1970 to 2016. Relevant references were selected and the included studies were manually reviewed. We included trials evaluating decompression surgery compared to decompression plus fusion surgery in treating patients with LSS. The primary outcomes analyzed were back pain, leg pain, Oswestry Disability Index scores (ODI), the quality-of-life EuroQol-5 Dimensions (EQ-5D), duration of operation, intraoperative blood loss, length of hospital stay, major complications, walking ability, number of reoperation, and finally clinically excellent and good rates. Data analysis was conducted using the Review Manager 5.2 software. Fifteen studies involving 17,785 patients with LSS were included. The overall effect mean difference (MD) (95% CI) in the differences between pre- and post-operative back pain, leg pain, operative time, intraoperative blood loss, and length of stay were 0.04 (-0.36, 0.44), 0.69 (-0.38, 1.76), -2.04 (-3.12, -0.96), -3.96 (-6.64, -1.27) and -4.21 (-10.03, 1.62) (z = 0.18, 1.26, 3.71, 2.89 and 1.41, respectively; P = 0.86, 0.55, 0.0002, 0.004 and 0.16, respectively) in random effects models. The overall effect MD (95% CI) in ODI, EQ-5D, and walking ability were 0.43 (-1.15, 2.00), 0.01 (-0.01, 0.03) and 0.04 (-0.49, 0.57) (z = 0.52, 1.16 and 0.15, respectively; P = 0.59, 0.24 and 0.88, respectively) in fixed effects models. The overall effect odds ratio (OR) (95% CI) of major complications, number of reoperations, and clinically excellent and good rates between the two groups were 0.70 (0.60, 0.81), 1.04 (0.90, 1.19) and 0.31 (0.06, 1.59) (z = 4.63, 0.53 and 1.40, respectively; P < 0.00001, 0.60 and 0.16, respectively). Our study reveals no difference in the effectiveness between the two surgical techniques. The additional fusion in the management of LSS yielded no clinical improvements over decompression alone within a 2-year follow-up period. But fusion resulted in a longer duration of operation, more blood loss, and a higher risk of complications. Therefore, the appropriate surgical protocol for LSS should be discussed further.