Femoral Neck Bone Mineral Density Change Is Associated with Shift in Standing Weight in Hemiparetic Stroke Patients

Abstract

The aim of this study was to explore the association between the proportion of body weight bearing of the paretic leg and the rate of femoral neck bone mineral density loss in acute first-ever stroke patients. Patients were divided into those bearing less weight (<50%) on the paretic leg (n = 11) and those bearing more weight (≥50%) on the paretic leg (n = 11). The change in bone mineral density (grams per square centimeter per year) was calculated from the initial and follow-up dual-energy x-ray absorptiometry (≥6 mos). The proportion of body weight bearing was calculated from the body weight bearing of each leg, which was measured with the patient standing on a tilt table. Compared with the patients bearing more weight on the paretic leg, the patients bearing less weight on the paretic leg had faster reduction in femoral neck bone mineral density. The proportion of body weight bearing was associated with the change in bone mineral density in the paretic (adjusted r = 51.0%, P < 0.001) and nonparetic (adjusted r = 32.4%, P < 0.005) legs. The stroke patients with proportion of body weight bearing of less than 50% on the paretic leg experienced faster bone loss and compromised bone density in the femoral neck. The proportion of body weight bearing may be useful to estimate the change in bone mineral density in paretic legs within the first year after stroke.