The Influence of Single-level Versus Multilevel Decompression on the Outcome in Multisegmental Lumbar Spinal Stenosis: Analysis of the Lumbar Spinal Outcome Study (LSOS) Data.

STUDY DESIGN: This is prospective multicenter cohort study.

OBJECTIVE: To assess whether patients with confirmed multisegmental lumbar spinal stenosis benefit more from a single-level or a multilevel decompression.

SUMMARY OF BACKGROUND DATA: In multisegmental lumbar spinal stenotic cases, the decision as to how many levels of stenosis need to be operated to achieve the best possible clinical outcome is still unknown and remains a controversy between spine surgeons.

MATERIALS AND METHODS: Patients of the Swiss Lumbar Stenosis Outcome Study (LSOS) with confirmed multisegmental LSS undergoing first-time decompression without fusion were enrolled in this study. The main outcomes of this study were Spinal Stenosis Measure (SSM) symptoms and function over time, measured at baseline, 6, 12, and 24 months follow-up. Further outcomes of interest were changes in SSM, numeric rating scale, feeling thermometer, the EQ-5D-EL, and the Roland and Morris disability questionnaire from baseline to 6, 12, and 24 months.

RESULTS: After 12 months, a total of 141 patients met the inclusion criteria; of these, 33 (23%) underwent a single-level and 108 (77%) a multilevel decompression. Multilevel decompression was associated with a significantly less favorable SSM symptoms and function score, respectively, as compared with single-level decompression. In all further outcomes of interest single-level as well as multilevel patients improved over time.

CONCLUSIONS: Our study showed that in multisegmental stenotic cases a single-level decompression was associated with a significantly more favorable SSM symptoms and function score, respectively, as compared with multilevel decompression. This study provides evidence that in multisegmental stenotic cases a single-level decompression might be sufficient to improve patient's symptoms and function.