Relationship of sagittal spinal alignment with low back pain and physical performance in the general population

Studies have suggested a relationship between sagittal spinal malalignment and low back pain (LBP). The current study investigated the relationship of spinal alignment with LBP and physical performance in 1491 individuals who attended the second follow-up visit of the Wakayama Spine Study. The sagittal vertical axis at C7 (C7 SVA) was measured by a spine surgeon. The occurrence of LBP within one month, pain intensity, Oswestry Disability Index (ODI), and physical performance (grip strength, 6-m walking time, chair stand test, one-leg standing test) were also evaluated. LBP in the previous month was determined using ODI, and indicators of physical performance were measured. The mean C7 SVA was 11.0 ± 42.7 mm and was significantly greater in older participants (p < 0.001). LBP was more prevalent in participants with a greater C7 SVA (< 40 mm, 35.7%; 40–95 mm, 47.3%; ≥ 95 mm, 59.4%; p < 0.001) and those with a higher ODI score (10.0%, 17.5%, and 29.4%, respectively; p < 0.001). Physical performance significantly decreased in participants with a greater C7 SVA (p < 0.001). Multiple linear regression analysis revealed that LBP and physical performance were significantly associated with C7 SVA (p < 0.001). Thus, sagittal spinal malalignment may lead to LBP and decreased physical performance.