Work

Central adiposity is associated with the severity and multiligamentous involvement of ossification of the posterior longitudinal ligament

Year: 2026

Type: article

Abstract: Ossification of the posterior longitudinal ligament (OPLL) is increasingly recognized as a metabolic ossification phenotype characterized by obesity-related abnormalities, particularly visceral adiposity. Although visceral fat has been implicated in the development of OPLL, its relationship with ossification severity and multiligamentous involvement remains unclear. This study aimed to examine whether anthropometric indices reflecting central adiposity show consistent associations with the burden of spinal ligament ossification. We retrospectively analyzed 252 individuals, including 163 patients with OPLL and 89 controls. Anthropometric indices-BMI and body roundness index (BRI)-were evaluated alongside CT-based measurements of visceral and subcutaneous fat areas. Ossification severity was quantified using a validated CT-based ossification index encompassing OPLL, ossification of the ligamentum flavum (OLF), ossification of the anterior longitudinal ligament (OALL), and ossification of the supra/interspinous ligaments (OSIL). Logistic regression, spline modeling, and sex-stratified analyses were performed. Patients with OPLL, particularly those with diffuse-type disease, exhibited significantly greater visceral adiposity and higher BMI and BRI values than controls. Both BMI and BRI were associated with the presence of diffuse OPLL, whereas their associations with localized OPLL were weaker. Nonlinear analyses showed that BMI was associated with ossification severity mainly within the lower BMI range, whereas BRI demonstrated generally linear associations across multiple ligamentous sites. These patterns were more evident in females. These findings suggest that anthropometric indices reflecting central adiposity may provide complementary information when evaluating the extent of spinal ligament ossification. While CT-derived visceral fat remains the direct measure of abdominal adiposity, indices, such as BRI, may offer additional context for understanding metabolic features associated with ossification burden in OPLL.

Source: JBMR Plus

DOI: 10.1093/jbmrpl/ziag165