US 12,144,774 B2
Spasticity assessment and rehabilitation support system for stroke patients using characteristic vector analysis
Jongho Lee, Ishikawa (JP); and Duk Shin, Shibuya (JP)
Assigned to Seahak Kim, Mukilteo, WA (US)
Filed by Seahak Kim, Mukilteo, WA (US)
Filed on Jan. 18, 2024, as Appl. No. 18/415,941.
Claims priority of provisional application 63/439,791, filed on Jan. 18, 2023.
Prior Publication US 2024/0238145 A1, Jul. 18, 2024
Int. Cl. A61H 1/02 (2006.01); A61B 5/00 (2006.01); A61B 5/11 (2006.01); A61B 5/389 (2021.01)
CPC A61H 1/0285 (2013.01) [A61B 5/1107 (2013.01); A61B 5/1114 (2013.01); A61B 5/389 (2021.01); A61B 5/4842 (2013.01); A61B 5/7225 (2013.01); A61H 2201/1207 (2013.01); A61H 2201/1635 (2013.01); A61H 2201/501 (2013.01); A61H 2201/5043 (2013.01); A61H 2201/5079 (2013.01); A61H 2201/5084 (2013.01); A61H 2230/605 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A system for assessing and rehabilitating spasticity in stroke patients, comprising:
a set of electrodes for recording eight electromyography (EMG) signals from at least four muscles involved in wrist movements;
a motion tracking module for tracking the kinematics of wrist joint motion including wrist angle, angular velocity, and angular acceleration;
a processing unit configured to calculate wrist joint torque based on the kinematics using an equation of motion and to normalize the recorded EMG signals based on a constant joint torque using an isometric contraction task;
a computational module for determining moment arms for each muscle based on the normalized EMG signals and the calculated wrist joint torque using a least squares optimization method;
a characteristic vector calculator for determining a vector indicating the state of spasticity based on the moment arms, wherein the characteristic vector calculator computes the vector using the linear sum of the moment arms of each muscle in both X and Y axes of the wrist movement; and
a motorized wrist system for assisting wrist movements of the stroke patient in a direction opposite to that indicated by the characteristic vector.