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Three-dimensional kinematic modelling of the human shoulder complex--Part II: Mathematical modelling and solution via
1Mechanical Engineering Department, King Saud University, Riyadh, Saudi Arabia.
Journal of Biomechanical Engineering
|May 1, 1989
Summary
This study quantifies joint sinus cones in the human shoulder complex using a 3D kinematic model. It introduces a "minimum joint motion" criterion to determine joint variables for accurate cone size and orientation, aiding biomechanical analysis.
Area of Science:
- Biomechanics
- Human anatomy
- Kinesiology
Background:
- The human shoulder complex involves intricate joint articulations.
- Understanding the kinematics of the shoulder is crucial for diagnosing and treating injuries.
- Previous models lacked precise quantitative data on individual joint sinus cones.
Purpose of the Study:
- To quantitatively determine individual joint sinus cones for the sternoclavicular, claviscapular, and glenohumeral joints.
- To develop a method for calculating joint variables based on humerus orientation and a minimum joint motion criterion.
- To establish the sizes and orientations of elliptical cones for individual joint sinuses.
Main Methods:
- Utilized a three-dimensional kinematic model of the human shoulder complex.
- Developed a mathematical description of humerus orientation using eight joint variables.
- Applied optimization techniques (Lagrange multipliers and flexible tolerance) with a "minimum joint motion" criterion.
- Employed in-vivo statistical data for upper arm circumductory motion.
Main Results:
- Successfully determined the sizes and orientations of elliptical joint sinus cones for the sternoclavicular, claviscapular, and glenohumeral joints.
- Validated the "minimum joint motion" criterion for solving kinematically redundant systems.
- Optimized joint variables were derived from in-vivo motion data.
Conclusions:
- The study provides a quantitative method for defining shoulder joint sinus cones.
- The findings contribute to a more accurate biomechanical model of the human shoulder.
- Results offer a basis for comparison with cadaveric measurements and clinical applications.
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