The Effect of Asymmetric Dynamic and Static Weight-bearing Force on Bone Mineral Density in Hemiplegic Stroke Patients : Preliminary Study

Im, Sun; Kang, Eugene; Lim, Seong Hoon; Chung, Myung Eun; Lee, Jong In; Ko, Young Jin; Kim, Hye Won

Abstract

OBJECTIVE
To measure the foot force and contact area distribution between the paretic and nonparetic sides during static and dynamic weight-bearing states, and to determine their relationship with BMD (bone mineral density). METHOD: Sixteen stroke patients (mean age=63.5+/-7.46 years) were included and BMDs of bilateral femurs were evaluated. Foot force and total foot contact areas were measured using the F-scan insole system. All values were expressed in ratio of paretic versus nonparetic sides.
RESULTS
The paretic side showed significantly smaller values in BMD, foot force and total contact area than the nonparetic sides (p<0.05). Femoral BMD ratio correlated significantly with dynamic weight bearing force ratio (r=0.58, p<0.05) and time elapsed since stroke as well (r=-0.17, p<0.05), while it did not correlate with either static weight-bearing force ratio (r=0.25, p>0.05), or total contact area ratio during both dynamic and static weight-bearing state (r=0.23, r=0.12, p>0.05). Multiple regression analysis showed that dynamic weight-bearing force ratio and time elapsed since stroke were independently related to BMD ratio (t=3.25, p<0.001 and t=-4.89, p<0.001).
CONCLUSION
The present study showed that foot force differences in the dynamic weight-bearing state significantly correlated to post-stroke BMD while foot contact area in both the static and dynamic weight-bearing state did not correlate to post-stroke BMD.