Does the wait for lumbar degenerative spinal stenosis surgery have a detrimental effect on patient outcomes? A prospective observational study

Background: Waits for elective spine surgery are common in Canada. We examined whether a prolonged wait for surgery for lumbar degenerative spinal stenosis was detrimental to outcome. Methods: In this prospective observational study, we enrolled 166 consecutive patients referred to our centre for treatment of lumbar degenerative spinal stenosis between 2006 and 2010. Outcome measures were assessed at referral, preoperatively and until 24 months postoperatively. Primary outcome measures were the physical and mental component summary scores of the 36-Item ShortForm Health Survey and the Oswestry Disability Index. Secondary outcome measures included the symptom severity scale of the Zurich Claudication Questionnaire, a numeric rating scale for back and leg pain, and patient satisfaction with treatment. Wait time was defined as the time from referral to surgery. Results: The follow-up rate at 2 years was 85%. The median wait time was 349 days. All health-related quality of life measures deteriorated during the waiting period, but there was no significant correlation between wait time and magnitude of the change in outcome measure. At 6 months postoperatively, the Pearson correlation was significantly positive between wait time and change in disability (r = 0.223), Zurich Claudication Questionnaire score (r = 0.2) and leg pain score (r = 0.221). At 12 months, the correlation remained significant for change in disability (r = 0.205) and was significant for change in mental well-being (r = –0.224). At 12 months, patients with a shorter wait (≤ 12 months) showed greater improvement in mental well-being (mean difference in change [and 95% confidence interval (CI)] 5.7 [1.4– 9.9]) and decrease in disability (–9.3 [95% CI –15.1 to –3.6]) and leg pain (–1.6 [95% CI –3.0 to –0.3]). There were no statistically significant differences in outcome or patient satisfaction with treatment between those with shorter and longer waits at 24 months. Interpretation: Patients awaiting spinal surgery experienced deterioration in health-related quality of life irrespective of the length of wait time. However, longer waits were associated with a delay in recovery during the first year after surgery.