Comorbidity prevalence of degenerative lumbar scoliosis in lumbar spinal stenosis: age-related radiological and symptomatological characteristics in a large sample

Background The aging population with lumbar spinal stenosis (LSS) is leading to a higher prevalence of coexisting conditions, particularly degenerative lumbar scoliosis (DLS). However, large-scale studies on the prevalence of DLS in LSS patients are limited. The surgical management of LSS with DLS is controversial. Berjano’s DSD classification provides a framework based on the relationship between the responsible segment and scoliosis apex. Understanding the distribution of these patterns is an essential step toward elucidating the clinical characteristics of LSS patients with coexisting DLS. Methods DLS was diagnosed according to the definition of a coronal curvature (main lumbar curve) of ≥10°. Patients were classified according to Berjano’s DSD classification. Spearmann correlation tests were conducted to examine the relationships between radiographic parameters and symptom scores in patients with coexisting conditions. Results A total of 443 patients (157 males and 286 females, mean age 65.5 ± 7.5 years, mean Cobb angle 18.0 ± 7.9°) met the criteria for DLS (Cobb angle ≥ 10°), leading to a coexisting prevalence of 26.2%, ranging from 12.0 to 35.6% increasing with age. Patients with Berjano type I, type II, type III, type IVa, and type IVb account for 35.0, 38.8, 13.3, 12.0, and 9.0%, respectively. In patients with LSS and comorbid DLS, VAS LBP and ODI scores were both correlated with sagittal parameters. VAS LBP was significantly correlated with the Cobb angle ( p = 0.001), while ODI scores showed significant correlations with the C7 plumb line to central sacral vertical line (C7PL-CSVL) ( p = 0.038). Meanwhile, significant correlations were observed between sagittal parameters, and the Cobb angle and C7PL-CSVL, respectively. The incidence of sagittal imbalance (SVA > 50 mm) in LSS patients with DLS was 41.1%, which increased with the severity of coronal imbalance. Conclusion The prevalence of DLS in LSS patients is 26.2%, increasing with age. Berjano type II represents the highest proportion (38.8%). Spinal deformity significantly correlates with clinical symptoms, with coronal and sagittal deformities being interrelated.