A New Approach to Assess Quality of Motion in Functional Task of Upper Limb in Duchenne Muscular Dystrophy

Featured Application The findings described in this paper could be treated as recommendations in a physical therapy program for DMD patients that focus on defining conditions along with the weight (light or heavy) that could give better muscle response in rehabilitation of DMD patients. (1) Background: This study presents a new method for the motion quantitative analysis of Duchenne muscular dystrophy patients (DMD) performing functional tasks in clinical conditions. (2) Methods: An experimental study was designed to define how different levels of external mass (light and heavy) influence the performance of the upper limbs of a tested DMD and reference subject (RS) during horizontal movements (level of the waist) under natural conditions (NC) and passive manipulator conditions (PMC); the kinematic data and muscle activity of four chosen superficial muscles (EMG) were recorded. (3) Results: A piecewise linear multi-regression analysis revealed high statistically significant results (R-2 >= 0.75) between the tested muscle activities and kinematic data in the tested DMD patient and RS. These results were used to define whether the neural control of the four tested muscles (processed EMG data) was correlated more with the displacement of the wrist joint or the center of mass of the tested upper limb while performing functional tests with a given external weight in a horizontal plane under NC or PMC. (4) Conclusions: The proposed approach can be used to estimate the contributions of the tested muscles to patients' motion performance and define whether this contribution is correlated with the kinematics or dynamics of the tested arm.

Automated summary

This study presents a new method for motion quantitative analysis in DMD patients. The results show that different levels of external mass influence the performance of upper limb movements and are statistically significant.