Imagama S, Ando K, Kobayashi K, et al. - A prospective cross-sectional cohort was conducted to assess the correlations of PI with lumbar osteophyte formation and disc degeneration, as well as spinal sagittal alignment and geriatric diseases, in middle-aged and elderly people. Researchers prospectively analyzed a sum of 1,002 volunteers (male: 434, female: 568, average age: 63.5) for lumbar osteophyte formation (Nathan class ≥ 2) and disc degeneration (disc score ≥ 3). This study ascertained high (PI > 51, n = 501) and low (PI ≤ 51, n = 501) PI groups. They compared clinical factors, frailty, sarcopenia, and physical quality of life (QOL) between these groups, and risk factors for lumbar osteophyte formation and disc degeneration were distinguished in multivariate logistic regression analysis. The study found that low PI was distinguished as a risk factor for lumbar osteophyte formation and disc degeneration, both of which decrease physical QOL in middle-aged and elderly people.