Intercarpal kinematics during wrist motion.

Twenty-two fresh cadaver specimens were analyzed using a three-dimensional biplanar roentgenographic kinematic technique to quantitate intercarpal motion. The large number of specimens provided substantial power to dramatically optimize the statistical significance of the measurements. It was confirmed that the bones of the distal carpal row behave as a single, functional unit with little intercarpal motion and are directly linked to movement of the third metacarpal. The scaphoid, lunate, and triquetrum exhibit significant "out of plane" motion, noted mainly in relation to the distal row bones. Measurable differences in the kinematics of the proximal row bones, relative to each other, were repeatedly defined.