Incidence of Revision Surgery After Decompression With vs Without Fusion Among Patients With Degenerative Lumbar Spinal Stenosis

IMPORTANCE: Only limited data derived from large prospective cohort studies exist on the incidence of revision surgery among patients who undergo operations for degenerative lumbar spinal stenosis (DLSS). OBJECTIVE: To assess the cumulative incidence of revision surgery after 2 types of index operations—decompression alone or decompression with fusion—among patients with DLSS. DESIGN, SETTING, AND PARTICIPANTS: This cohort study analyzed data from a multicenter, prospective cohort study, the Lumbar Stenosis Outcome Study, which included patients aged 50 years or older with DLSS at 8 spine surgery and rheumatology units in Switzerland between December 2010 and December 2015. The follow-up period was 3 years. Data for this study were analyzed between October and November 2021. EXPOSURES: All patients underwent either decompression surgery alone or decompression with fusion surgery for DLSS. MAIN OUTCOMES AND MEASURES: The primary outcome was the cumulative incidence of revision operations. Secondary outcomes included changes in the following patient-reported outcome measures: Spinal Stenosis Measure (SSM) symptom severity (higher scores indicate more pain) and physical function (higher scores indicate more disability) subscale scores and the EuroQol Health-Related Quality of Life 5-Dimension 3-Level questionnaire (EQ-5D-3L) summary index score (lower scores indicate worse quality of life). RESULTS: A total of 328 patients (165 [50.3%] men; median age, 73.0 years [IQR, 66.0-78.0 years]) were included in the analysis. Of these, 256 (78.0%) underwent decompression alone and 72 (22.0%) underwent decompression with fusion. The cumulative incidence of revisions after 3 years of follow-up was 11.3% (95% CI, 7.4%-15.1%) for the decompression alone group and 13.9% (95% CI, 5.5%-21.5%) for the fusion group (log-rank P = .60). There was no significant difference in the need for revision between the 2 groups over time (unadjusted absolute risk difference, 2.6% [95% CI, −6.3% to 11.4%]; adjusted absolute risk difference, 3.9% [95% CI, −5.2% to 17.0%]; adjusted hazard ratio, 1.40 [95% CI, 0.63-3.13]). The number of revisions was significantly associated with higher SSM symptom severity scores (β, 0.171; 95% CI, 0.047-0.295; P = .007) and lower EQ-5D-3L summary index scores (β, −0.061; 95% CI, −0.105 to −0.017; P = .007) but not with higher SSM physical function scores (β, 0.068; 95% CI, −0.036 to 0.172; P = .20). The type of index operation was not significantly associated with the corresponding outcomes. CONCLUSIONS AND RELEVANCE: This cohort study showed no significant association between the type of index operation for DLSS—decompression alone or fusion—and the need for revision surgery or the outcomes of pain, disability, and quality of life among patients after 3 years. Number of revision operations was associated with more pain and worse quality of life.