Objectives. Cadaveric models of the shoulder evaluate discrete motion segments
using the glenohumeral joint in isolation over a defined trajectory.
The aim of this study was to design, manufacture and validate a
robotic system to accurately create three-dimensional movement of
the upper body and capture it using high-speed motion cameras. Methods. In particular, we intended to use the robotic system to simulate
the normal throwing motion in an intact cadaver. The robotic system
consists of a lower frame (to move the torso) and an upper frame
(to move an arm) using seven actuators. The actuators accurately
reproduced planned trajectories. The marker setup used for motion
capture was able to determine the six degrees of freedom of all
involved joints during the planned motion of the end effector. Results. The testing system demonstrated high precision and accuracy based
on the expected versus observed displacements of individual axes.
The maximum coefficient of variation for displacement of unloaded
axes was less than 0.5% for all axes. The expected and observed
actual displacements had a high level of correlation with coefficients
of determination of 1.0 for all axes. Conclusions. Given that this system can accurately simulate and track simple
and complex motion, there is a new opportunity to study kinematics
of the shoulder under normal and
