Abstract
We propose a novel method, requiring no expensive specialized equipment, to evaluate trunk rotation and upper limb strength. By combining a digital ratchet wrench and foot load measurement device＜s＞,one can simultaneously measure trunk rotation torque and center of gravity (COG) displacement in free-standing patients adopting stances typical of activities of daily living (ADL) including work environments.Preliminary experiments measured 14.9 Nm maximum torque during trunk rotation. Future work aims to quantify the relationships between torque values, trunk rotation, and upper limb strength, to determine metrics for correlations with COG variance.Our main goal is to elucidate the causal relationship between trunk stability and upper limb force exertion. By analyzing features of COG, we aim to determine how the trunk maintains stability during upper limb movements and evidence of the impact of trunk stability on upper limb motor performance.The evaluation method developed in this study is expected to contribute to several fields.Work improvement and injury prevention: By quantitatively clarifying the features of physical load associated with task performance, this research may inform safer work postures and load reduction strategies to enhance work productivity and reduce occupational injury risk.Rehabilitation and training: To inform treatment of patients with chronic lower back pain, athletes, and general training, quantifying trunk rotation and associated upper limb strength and analyzing COG movement patterns can lead to personalized and effective intervention programs. COG trajectory data shows potential for novel rehabilitation training for patients with hemiplegia, Parkinson's disease, pusher syndrome, and unilateral spatial neglect.Through these endeavors, this research aims to establish a robust foundation contributing to diverse fields including sports,rehabilitation, and occupational science.
