A new classification system for degenerative spondylolisthesis of the lumbar spine.

ABSTRACT

PURPOSE: There is no consensus for a comprehensive analysis of degenerative spondylolisthesis of the lumbar spine (DSLS). A new classification system for DSLS based on sagittal alignment was proposed. Its clinical relevance was explored. METHODS: Health-related quality-of-life scales (HRQOLs) and clinical parameters were collected SF-12, ODI, and low back and leg pain visual analog scales (BP-VAS, LP-VAS). Radiographic analysis included Meyerding grading and sagittal parameters segmental lordosis (SL), L1-S1 lumbar lordosis (LL), T1-T12 thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), and sagittal vertical axis (SVA). Patients were classified according to three main types-1A preserved LL and SL; 1B preserved LL and reduced SL (≤5°); 2A PI-LL ≥10° without pelvic compensation (PT < 25°); 2B PI-LL ≥10° with pelvic compensation (PT ≥ 25°); type 3 global sagittal malalignment (SVA ≥40 mm). RESULTS: 166 patients (119 F 47 M) suffering from DSLS were included. Mean age was 67.1 ± 11 years. DSLS demographics were, respectively type 1A 73 patients, type 1B 3, type 2A 8, type 2B 22, and type 3 60. Meyerding grading was grade 1 (n = 124); grade 2 (n = 24). Affected levels were L4-L5 (n = 121), L3-L4 (n = 34), L2-L3 (n = 6), and L5-S1 (n = 5). Mean sagittal parameter values were PI 59.3° ± 11.9°; PT 24.3° ± 7.6°; SVA 29.1 ± 42.2 mm; SL 18.2° ± 8.1°. DSLS types were correlated with age, ODI and SF-12 PCS (ρ = 0.34, p < 0.05; ρ = 0.33, p < 0.05; ρ = -0.20, and p = 0.01, respectively). CONCLUSION: This classification was consistent with age and HRQOLs and could be a preoperative assessment tool. Its therapeutic impact has yet to be validated. LEVEL OF EVIDENCE 4.