Prevalence and outcomes of bowel dysfunction in surgically treated patients with lumbar spinal stenosis

BACKGROUND AND AIMS: Lumbar spinal stenosis is primarily associated with back pain and lower limb symptoms, whereas cauda equina symptoms, such as bowel dysfunction, that is, defecation difficulties and/or incontinence, are less frequently recognized. The prevalence of bowel dysfunction in patients with lumbar spinal stenosis and the impact of surgical treatment on these symptoms remain unclear. The aim of this study was to investigate the prevalence of bowel dysfunction in patients with lumbar spinal stenosis and whether spinal surgery alleviates these symptoms. METHODS: A retrospective survey was sent to all patients who underwent surgical treatment for lumbar spinal stenosis at Tampere University Hospital in 2023. Bowel dysfunction symptoms were assessed using a questionnaire addressing both baseline and postoperative status. Baseline characteristics, operative details, and prospectively collected patient-reported outcome measures were obtained from the medical records and hospital databases. RESULTS: Of the 338 patients who underwent surgery, 154 (46%) completed the survey and were included in the analysis. Preoperative bowel dysfunction was reported in 57 (37%) patients. Among them, 19 (33%) patients experienced postoperative improvement, including complete resolution in 14 (25%) cases. Conversely, 21 (14%) patients reported postoperative worsening, including 13 (8%) patients with new-onset symptoms. Acute surgery was independently associated with postoperative deterioration (odds ratio = 4.9, 95% confidence interval = 1.4-16.7, p = 0.012). Overall, 43 (28%) patients reported bowel dysfunction both preoperatively and postoperatively. CONCLUSIONS: Bowel dysfunction is common and may be under-recognized in patients with lumbar spinal stenosis. Although approximately one-third of patients improved after decompressive spine surgery, 14% reported worsening of symptoms. This suggests that routine assessment of bowel symptoms may be relevant in lumbar spinal stenosis patients.