Effects of elbow immobilization on upper extremity activity

Background: It has been dogma that handedness greatly impacts daily activities. Interruptions in the ability to utilize the dominant arm due to neuromusculoskeletal injuries could negatively impact performance of activities of daily living. Daily activity can be measured using activity monitors. This study aimed to examine how arm dominance impacts function by immobilizing the arms of healthy individuals. Methods: Ten individuals wore four upper extremity activity monitors for three days—one day without immobilization, one day with their dominant arm immobilized, and one day with their non-dominant arm immobilized. Triaxial acceleration data was used to calculate average daily activity and an asymmetry index. Between-condition differences were examined. Findings: During dominant arm immobilization, the dominant forearm had significantly less average daily activity when compared to the no immobilization day (p = .0001) and the non-dominant immobilized day (p < .0001). A similar trend was observed at the non-dominant forearm when the non-dominant arm was immobilized. Immobilization of an arm increased asymmetry index and reliance on the non-immobilized arm. Significant differences in asymmetry index were not observed between the two casted conditions. Interpretation: When an upper extremity was casted, immobilized forearm and upper arm average daily activity was comparable. Dominance did not have an effect on asymmetry index. Immobilization affected asymmetry index compared to no immobilization. This study has demonstrated that regardless of arm immobilized, there will be a reliance on the contralateral limb about twice as much as the immobilized limb. This could prove problematic if the contralateral limb is restricted or injured, limiting independent.