Prognostic factors associated with the surgical indication for lumbar spinal stenosis patients less responsive to conservative treatments: An investigator-initiated observational cohort study.

BACKGROUND: A few cohort studies have determined which patients with lumbar spinal stenosis are likely to need surgery because of the deterioration of symptoms. However, there are still insufficient data regarding the management of lumbar spinal stenosis due to lack of prognostic factors associated with the need for surgery. The purpose of this study was to identify the prognostic factors associated with the need for surgical treatment in patients with lumbar spinal stenosis.

METHODS: Patients with lumbar spinal stenosis from our hospital and related facilities were enrolled. Eligibility criteria were as follows: age 50-85 years and the patient's conditions met the definition of lumbar spinal stenosis; the presence of neurogenic intermittent claudication caused by numbness and/or pain in the lower limbs; and magnetic resonance imaging-confirmed symptomatic LSS. We followed 274 patients (151 men; mean age, 71 ± 7.4 years) for 3 years to identify prognostic factors. We used a multivariate logistic regression model to investigate the association between the indication for surgical treatment (within 3 years) and age, sex, complications, depression, illness duration, the presence of cauda equina symptoms, and the presence of degenerative spondylolisthesis/scoliosis.

RESULTS: In the survey conducted 3 years after treatment, 185 patients responded (follow-up rate 67.5%). In 82 patients, surgery was performed during the follow-up period. The multivariate logistic regression model showed that the presence of cauda equina symptoms and the presence of degenerative spondylolisthesis/scoliosis were significantly associated with the indication for surgical treatment within 3 years.

CONCLUSIONS: This study showed that the presence of cauda equina symptoms and degenerative spondylolisthesis/scoliosis were prognostic factors associated with the indication for surgery in patients with lumbar spinal stenosis.