Changes in bone density and geometry of the upper extremities after stroke : a case report

Abstract

Purpose: The purpose of this study was to examine changes in bone density and geometry of the forearm region and motor function of the paretic upper extremity in a person with subacute stroke. Client Description: The participant was a 48-year-old man with right hemiparesis. Intervention: Not applicable. Measures and Outcomes: The assessment of upper-extremity (UE) function and bone imaging took place at 3 months and 12 months after stroke. The participant had moderate motor impairment and severe disuse of the paretic UE 3 months after stroke. During the follow-up period, no substantial change in paretic UE function was observed. At the 12 month follow-up, the areal bone mineral density (aBMD) of the ultradistal and mid-regions of the paretic forearm, as measured by dual-energy X-ray absorptiometry, sustained a significant reduction of 7.9% and 5.9%, respectively. The non-paretic side, in contrast, had a significant 4.0% increase in aBMD of the mid-forearm and a 2.8% increase in aBMD of the total forearm. Significant findings from peripheral quantitative computed tomography were a reduction in total volumetric bone mineral density (-12.1%) and bone strength index (-20.6%) in the radius distal epiphysis on the paretic side and an increase in cortical bone mineral content (2.0%) and bone strength index (7.6%) in the radius diaphysis on the non-paretic side. Implications: After a stroke that resulted in moderate to severe UE impairment, a significant decline in bone mineral density was identified in various skeletal sites in the forearm region as the participant entered the subacute and chronic stages of recovery. The results point to the potential importance of early rehabilitative intervention in preventing unfavourable bone changes in the paretic upper limb among individuals with stroke.