Novel elemental grading system for radiographic lumbar spondylosis in a population based-cohort study of a Japanese mountain village.

Abstract

Lumbar radiography is a primary screening tool for lumbar spondylosis (LS). Kellgren-Lawrence (KL) classification is widely used to evaluate LS; however, it cannot individually evaluate each radiographic feature. The purpose of this study was to 1) evaluate radiographic LS using a novel elemental grading system and 2) investigate the relationship between the grades of radiographic LS and low back pain (LBP) in a population-based cohort study. A total of 260 (75 men, 185 women; mean age, 71.5 ± 8.7 years) participants were included in this study. Participants were divided into two groups according to the presence of LBP (LBP- and LBP+ groups). Radiographic features, including osteophyte (OP), disc height narrowing (DHN), vertebral sclerosis (VS), and spondylolisthesis (SL), were classified between grades of 0-2 grades according to the extent of radiographic changes. The sum of grades at each intervertebral level was designated as the intervertebral grade (IG). Intra- and inter-observer reliability (kappa coefficient) of OP, DHN, VS, and SL were 0.82-0.92. OP, DHN, VS, and IG grades were significantly higher in the LBP+ group than in the LBP- group. There were no significant differences in KL grades between the LBP- and LBP+ groups. Logistic regression analysis demonstrated that VS grade was a significant independent factor associated with LBP. The novel elemental grading system of LS would reflect LBP more accurately than the KL classification by individually evaluating each radiographic feature.