The upper limb motion deviation index: A new comprehensive index of upper limb motion pathology

Purpose: The aim of the research was to formulate a new index enabling assessment of the overall pathology of the upper limb movement. It defines the difference between the pathological movement and a normal movement pattern. Methods: Methodology of determining the index is based on a mathematical algorithm for calculating the Gait Deviation Index which is based on advanced methods of image comparison. To calculate the ULMDI index, one must divide the analyzed movement into cycles appropriate to the nature of the movement (similarly in gait it is the gait cycle) and then determine kinematic quantities (courses of joint angles). Results: A group of 23 healthy people (10 women: k1–k10 and 13 men: m1–m13) as the reference group and a group of 3 persons with mobility impairments (p1–p3) took part in the research. Time values of the angles of the joints on both upper limbs were registered and then ULMDI indexes were calculated. Conclusions: It has been shown that the developed ULMDI index allows to detect the deviations from the accepted norm in the performance of movements. The results showed that both the description of the motor dysfunction of examined person based on the diagnosis of the physician, a detailed analysis of kinematic waveforms received during the tests and the calculated values provide a coherent picture of the state of a human movement. The index analysis is less time-consuming for the doctor, and the comparison of the results at various stages of therapy gives an objective picture of the rehabilitation progress.