Decompression Alone Versus Interspinous/Interlaminar Device Placement for Degenerative Lumbar Pathologies: Systematic Review and Meta-Analysis

Abstract

Introduction: Interspinous devices (ISDs) and interlaminar devices (ILDs) are marketed as alternatives to conventional surgery for degenerative lumbar conditions; comparisons with decompression alone are limited. The present study reviews the extant literature comparing the cost and effectiveness of ISDs/ILDs with decompression alone.

Methods: Articles comparing decompression alone with ISD/ILD were identified; outcomes of interest included general and disease-specific patient-reported outcomes, perioperative complications, and total treatment costs. Outcomes were analyzed at <6 weeks, 3 months, 6 months, 1 year, 2 years, and last follow-up. Analyses were performed using random effects modeling.

Results: Twenty-nine studies were included in the final analysis. ILD/ISD showed greater leg pain improvement at 3 months (mean difference, -1.43; 95% confidence interval, [-1.78, -1.07]; P < 0.001), 6 months (-0.89; [-1.55, -0.24]; P = 0.008), and 12 months (-0.97; [-1.25, -0.68]; P < 0.001), but not 2 years (P = 0.22) or last follow-up (P = 0.09). Back pain improvement was better after ISD/ILD only at 1 year (-0.87; [-1.62, -0.13]; P = 0.02). Short-Form 36 physical component scores or Zurich Claudication Questionnaire (ZCQ) symptom severity scores did not differ between the groups. ZCQ physical function scores improved more after decompression alone at 6 months (0.35; [0.07, 0.63]; P = 0.01) and 12 months (0.23; [0.00, 0.46]; P = 0.05). Oswestry Disability Index and EuroQoL 5 dimensions scores favored ILD/ISD at all time points except 6 months (P = 0.07). Reoperations (odds ratio, 1.75; [1.23, 2.48]; P = 0.002) and total care costs (standardized mean difference, 1.19; [0.62, 1.77]; P < 0.001) were higher in the ILD/ISD group; complications did not differ significantly between the groups (P = 0.41).

Conclusions: Patient-reported outcomes are similar after decompression alone and ILD/ISD; the observed differences do not reach accepted minimum clinically important difference thresholds. ISD/ILDs have higher associated costs and reoperation rates, suggesting current evidence does not support ILD/ISDs as a cost-effective alternative to decompression alone.

Keywords: Cost-effectiveness; Evidence-based medicine; Interlaminar device; Interspinous device; Lumbar stenosis.