What factors predict the best outcomes for older patients operated on for grade I degenerative lumbar spondylolisthesis? A machine learning analysis from the Quality Outcomes Database

The authors' analysis of older (≥ 65 years old) patients undergoing surgery for grade I spondylolisthesis revealed two distinct clusters: one with optimal and the other with suboptimal outcomes. The addition of fusion to a procedure was associated with superior outcomes, as patients who received fusion had a 70% increase in the odds of reaching an optimal outcome. Age was not significantly associated with outcome, implying that there is no clear cutoff for surgical eligibility in older patients. These findings may inform decision-making between decompression alone versus decompression with fusion in older patients.