What Is the Clinical Relevance of Radiographic Nonunion After Single-Level Lumbar Interbody Arthrodesis in Degenerative Disc Disease?

better improvements in ODI (P<0.001) and NRS back pain Study Design. Meta-analysis of 4 randomized controlled clinical trials (RCTs). Objective. The aim of the study was to determine if patients with degenerative disc disease who achieve radiographic fusion after single-level lumbar interbody arthrodesis have better clinical outcomes than patients with radiographic pseudarthrosis at 12 and 24 months postoperative. Summary of Background Data. The clinical relevance of successful fusion after lumbar arthrodesis with recombinant human bone morphogenetic protein-2 or iliac crest bone autograft has recently been questioned in the literature. Methods. Individual patient-level data of 4 RCTs were obtained from the Yale University Open Data Access Project project and analyzed. Clinical outcomes (Oswestry Disability Index [ODI]; Numeric Rating Scales [NRSs] for back and leg pain) were compared between patients with radiographically confirmed fusion and those with radiographic nonunion 1 and 2 years postoperative. The results of each study were first analyzed separately, and then were pooled by meta-analysis. The GRADE approach was applied to evaluate the level of evidence. Results. A total of 496 patients with clinical and radiographic data at 1and 2-year follow-ups were identified. Of these, 5.5% (95% confidence interval: 3.7; 8.3) had radiographic nonunion which did not require reoperation. Patients with fusion had