ISB recommendation on definitions of joint coordinate systems of various joints for the reporting of human joint motion-Part II: shoulder, elbow, wrist and hand

Biomechanical models of the musculoskeletal system are frequently used to study neuromuscular control and simulate surgical procedures. To be broadly applicable, a model must be accessible to users, provide accurate representations of muscles and joints, and capture important interactions between joints. We have developed a model of the upper extremity that includes 15 degrees of freedom representing the shoulder, elbow, forearm, wrist, thumb, and index finger, and 50 muscle compartments crossing these joints. The kinematics of each joint and the force-generating parameters for each muscle were derived from experimental data. The model estimates the muscle-tendon lengths and moment arms for each of the muscles over a wide range of postures. Given a pattern of muscle activations, the model also estimates muscle forces and joint moments. The moment arms and maximum moment-generating capacity of each muscle group (e.g., elbow flexors) were compared to experimental data to assess the accuracy of the model. These comparisons showed that moment arms and joint moments estimated using the model captured important features of upper extremity geometry and mechanics. The model also revealed coupling between joints, such as increased passive finger flexion moment with wrist extension. The computer model is available to researchers at http://nmbl.stanford.edu.

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A model of the upper extremity for simulating musculoskeletal surgery and analyzing neuromuscular control

Human movement analysis using stereophotogrammetry. Part 1: theoretical background.

The mechanism underlying gender disparity in anterior cruciate ligament injury risk is likely multifactorial in nature. Several theories have been proposed to explain the mechanisms underlying the gender difference in anterior cruciate ligament injury rates. These theories include the intrinsic variables of anatomical, hormonal, neuromuscular, and biomechanical differences between genders and extrinsic variables. Identification of both extrinsic and intrinsic risk factors associated with the anterior cruciate ligament injury mechanism may provide direction for targeted prophylactic treatment to high-risk individuals.

Ge Wu

Papers

ISB recommendation on definitions of joint coordinate systems of various joints for the reporting of human joint motion-Part II: shoulder, elbow, wrist and hand

ISB recommendation on definitions of joint coordinate system of various joints for the reporting of human joint motion—part I: ankle, hip, and spine

ISB recommendation on definitions of joint coordinate system of various joints for the reporting of human joint motion, I: ankle, hip, and spine

Distinguishing fall activities from normal activities by velocity characteristics.