In vitro simulation of physiologic human shoulder motion

We present initial performance metrics of a robotic system for in vitro simulation of 3D physiologic human shoulder motion. Scapular and humeral positions and orientations in the cadaver were driven by 3D human shoulder motions acquired using a biplane fluoroscopy system. An industrial robot base allowed dynamic 3D orientation of the scapula and active muscle tensioning applied to the humerus provided articulation of the humerus to achieve prescribed glenohumeral joint angles. This system will allow laboratory simulation of motions from healthy, pathologic, and surgically altered populations using native cadaver anatomy and specimens after arthroplasty or soft tissue repair.