Tibial Bone Geometry in Chronic Stroke Patients: Influence of Sex, Cardiovascular Health, and Muscle Mass

Abstract

This study aimed to examine the geometry of the tibia in chronic stroke survivors. Fifty-five ambulatory individuals with chronic stroke were included in the study. pQCT was used to obtain a cross-sectional scan of the tibia at the 30% site on both the paretic and nonparetic sides. Leg lean mass was derived from a total body scan using DXA. Each subject was also evaluated for peak oxygen consumption rate, spasticity, and functional mobility. Paired t-tests were used to compare the pQCT parameters between the two sides. Multiple linear regression analysis was used to identify the significant determinants of tibial bone strength index (BSI). In men, marrow cavity area on the paretic side was significantly greater than the nonparetic side (p = 0.011), whereas the total bone area showed no significant side-to-side difference (p = 0.252). In women, total bone area on the paretic side was significantly smaller than the nonparetic side (p = 0.003), whereas the marrow cavity area had no side-to-side difference (p = 0.367). Peak oxygen consumption (r(2) = 0.739, F(5,49) = 22.693, p < 0.001) and paretic leg lean mass (r(2) = 0.802, F(6,48) = 32.475, p < 0.001) remained independently associated with tibial BSI, after controlling for age, sex, body mass index, years since stroke onset, and physical activity level. The geometry of the tibia in stroke patients showed sex-specific side-to-side differences. The results suggested that, whereas endosteal resorption was apparent in men, periosteal resorption was more predominant in women. The results also highlight the potential importance of promoting cardiovascular health and leg muscle mass in enhancing bone geometry in chronic stroke survivors.