Effect of Wrist and Inter-phalangeal Thumb Movement on Zone II Flexor Pollicis Longus Tendon Tension in a Human Cadaver Model

[...]the within-specimen variance component was only 9 to 23% of the total variance at a given angle. Thumb inter-phalangeal (IP) and wrist joint positions were measured with a three-dimensional optical motion analysis system FPL forces in Zone II were measured during (1) passive IP thumb motion while the wrist was held at 30° flexion, 30° and 60° extension, 20° radial deviation and 40° ulnar deviation, (2) synergistic wrist motion, and (3) induced active IP flexion with the wrist and carpal-metacarpal (CMC) joints in a neutral position.