Joint Center Movement Analysis and 3D Motion Modeling of Upper Arm - Comparison of Several Algorithms with the Visual 3-D Program

JOINT CENTER MOVEMENT ANALYSIS AND 3D MOTION MODELING OF UPPER ARM MOVEMENTSCOMPARISON OF SEVERAL ALGORITHMS WITH THE VISUAL 3-D PROGRAM By Leena Joseph, B.E. Biomedical Engineering A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University. Virginia Commonwealth University, 2005 Major Director: Dr. Peter S. Lum Associate Professor, Department of Biomedical Engineering 600 out of every 100,000 people in the United States today suffer from some form of cerebellar disease that causes major abnormalities in the equilibrium and aligned, coordinated movement of the body. Hence it becomes essential to diagnose the extent of the movement and gait disorder and provide required therapy to the patients. Various developments have been made in the designing and application of interactive software system for body positioning. Object oriented design techniques are used in the field of software engineering for interactive geometric representation of system behavior. Motion xiv analysis of the upper and lower extremities of the body could be beneficial in the diagnosis and therapy of numerous orthopedic and neurological ailments. Mathematical models of neuro musculoskeletal dynamics establish a scientific basis for movement analysis. As mentioned above, an interactive geometric representation of the system behavior is an important diagnostic tool in orthopedic therapy. This realistic depiction of the human body with respect to the model is a very effective diagnostic tool for clinicians. There are existing biomechanical modeling tools like Visual 3-D etc, that are used for motion analysis. Visual 3-D was developed by the movement disorders laboratory at NIH. The preferred method is to place markers on the segments and calculate the joint center locations using a rigid-body assumption. However studies have shown that markers on the joint centers are subject to artifact (skin movement). Moreover, very few details are provided on the algorithm used by Visual 3-D, and no "fixes" are provided for marker dropout. This project aims at testing the accuracy of existing biomechanical movement analysis software Visual 3D by calculating the rigid body motion from the spatial coordinates of the markers clusters on the subject's upper extremities. This project tries to emulate their approach in a simple and effective manner and at the same time validate the approach by testing it by three different methods by calculating the elbow and wrist locations during a forward reaching motion of the subject. A mathematical model is developed by determining a relationship between the projections of a particular point in X v two different planes or on a single plane in two different directions [Kinzel, G.L. et. al. 19721. The computer simulations are performed using MATLAB to calculate the lunematical parameters from the co-ordinates of projections of markers placed on the upper extremities of the subject's body. This relation will aid in quantitative motion analysis of the upper extremities in the rehabilitation setting. This can be extended to in-depth gait analysis of the lower extremities too. This type of biomechanical movement analysis allows us to understand the dynamic implications of a particular impairment, such as spasticity or weakness, in a particular muscle group. Chapter