The Reverse Shoulder Prosthesis (RSP®) was the first reverse shoulder design to successfully incorporate a center of rotation (COR) lateral to the glenoid.
Patients presenting with an irreparable, rotator cuff deficient shoulder joint with severe arthropathy typically show evidence of an upward displacement of the humeral head with respect to the glenoid and a loss of glenohumeral joint space. Unfortunately, the functional outcomes using conventional surgical methods are severely limited and typically fail.
The Reverse® Shoulder Prosthesis is a semiconstrained design concept that reverses the shoulder anatomy by lateralizing the shoulder joint to effectively resist the superior pull of the deltoid muscle and optimize soft tissue balancing.
• Grossly rotator cuff deficient shoulder joint with severe arthopathy;
• A previously failed joint replacement with a grossly rotator cuff deficient shoulder joint;
• Evidence of upward displacement of the humeral head with respect to the glenoid;
• Loss of glenohumeral joint space
• Both lateral offset and peripheral screw type affected the magnitude of baseplate motion.
• Baseplate motion for Delta III components and Reverse® Shoulder Prosthesis components fixed with 5.0mm captured screws were below the 150 μm of motion generally accepted as the threshold for bone ingrowth.
• Stable fixation was achieved for the Reverse Shoulder Shoulder Prosthesis neutral components despite a substantially (69%) greater moment at the baseplate-foam interface compared with the Delta III.