Effectiveness and safety of interspinous spacer versus decompressive surgery for lumbar spinal stenosis: A meta-analysis of randomized controlled trials

STUDY DESIGN: A meta-analysis of randomized controlled trials. OBJECTIVE: Our meta-analysis was conducted to investigate whether interspinous spacer (IS) results in better performance for patients with lumbar spinal stenosis (LSS) when compared with decompressive surgery (DS). BACKGROUND DATA: DS and IS are common surgeries for the treatment of LSS. However, controversy remains as to whether the IS is superior to DS. METHODS: We comprehensively searched PubMed, EMBASE, and Cochrane Central Register of Controlled Trials for prospective randomized controlled trials that compared IS versus DS for LSS. The retrieved results were last updated on July 30, 2023. RESULTS: Eight studies involving 852 individuals were included in the meta-analysis. The pooled data indicated that IS was superior to DS considering shorter operation time (P = .003), lower dural violation rate (P = .002), better Zurich Claudication Questionnaire Physical function score (P = .03), and smaller foraminal height decrease (P = .004), but inferior to DS considering the higher rate of reoperation (P < .0001). There was no significant difference between the 2 groups regarding hospital stay (P = .26), blood loss (P = .23), spinous process fracture (P = .09), disc height decrease (P = .87), VAS leg pain score (P = .43), VAS back pain score (P = .26), Oswestry Disability Index score (P = .08), and Zurich Claudication Questionnaire symptom severity (P = .50). CONCLUSIONS: In summary, we considered that IS had similar effects with DS in hospital stay, blood loss, spinous process fracture, disc height decrease, VAS score, Oswestry Disability Index score, and Zurich Claudication Questionnaire Symptom severity, and was better in some indices such as operation time, dural violation, Zurich Claudication Questionnaire Physical function, and foraminal height decrease than DS. However, due to the higher rate of reoperation in the IS group, we considered that both IS and DS were acceptable strategies for treating LSS. As a novel technique, further well-designed studies with longer-term follow-up are needed to evaluate the effectiveness and safety of IS.