The effects of decreased physical activity to bone mineral density in hemiparetic stroke patients

Choi, Eun Kyoung

Abstract

BACKGROUND: Hemiparesis caused by stroke decreases muscle force and body weight loading in paralyzed extremities and results in a decrease in physical activity. Thus, decreased physical activity can be an important determinant of bone loss and the risk of bone fracture in hemiparetic stroke patients. The aim of this study was to investigate any difference between the paretic and non-paretic limb's bone mineral density (BMD) and evaluate the relationship between several clinical variables and the BMD of paretic limbs.
METHODS
Seventy-four hemiparetic patients (45 males, 29 females, mean age 55.7 years) were enrolled. The BMD of radius, femur and spine was measured using dual energy X-ray absorptiometry.
RESULTS
The BMD of paretic limbs was significantly lower compared with non-paretic side at the radius as well as the femur (p<0.05). Decrease rate (%) of the BMD was not significantly different between the paretic radius and the femur. In addition, decrease rate (%) of BMD in the paretic limbs well correlated with duration of hemiparesis and physical ability (p<0.05).
CONCLUSIONS
This study provides evidence that the BMD is affected by physical activity, and lack of mobility and weight-bearing after stroke are an important factor for the greater bone loss in the paretic limbs. Therefore, study looking for medical program for diagnosis and preventing the bone loss early after stroke should be established.