Predominant leg pain is associated with better surgical outcomes in degenerative spondylolisthesis and spinal stenosis: Results from the Spine Patient Outcomes Research Trial (SPORT)

Study Design.: As-treated analysis of the Spine Patient Outcomes Research Trial. Objective.: To compare baseline characteristics and surgical and nonoperative outcomes in degenerative spondylolisthesis (DS) and spinal stenosis (SpS) patients stratified by predominant pain location (i.e., leg vs. back). Summary of Background Data.: Evidence suggests that DS and SpS patients with predominant leg pain may have better surgical outcomes than patients with predominant low back pain (LBP). Methods.: The DS cohort included 591 patients (62% underwent surgery), and the SpS cohort included 615 patients (62% underwent surgery). Patients were classified as leg pain predominant, LBP predominant, or having equal pain according to baseline pain scores. Baseline characteristics were compared between the 3 predominant pain location groups within each diagnostic category, and changes in surgical and nonoperative outcome scores were compared for 2 years. Longitudinal regression models including baseline covariates were used to control for confounders. Results.: Among DS patients at baseline, 34% had predominant leg pain, 26% had predominant LBP, and 40% had equal pain. Similarly, 32% of SpS patients had predominant leg pain, 26% had predominant LBP, and 42% had equal pain. DS and SpS patients with predominant leg pain had baseline scores indicative of less severe symptoms. Leg pain predominant DS and SpS patients treated surgically improved significantly more than LBP predominant patients on all primary outcome measures at 1 and 2 years. Surgical outcomes for the equal pain groups were intermediate to those of the predominant leg pain and LBP groups. The differences in nonoperative outcomes were less consistent. Conclusion.: Predominant leg pain patients improved significantly more with surgery than predominant LBP patients. However, predominant LBP patients still improved significantly more with surgery than with nonoperative treatment.