Reverse shoulder joint replacement is an increasingly common surgical intervention. However there are concerns in relation to such joint replacement, while novel designs of reverse shoulder prostheses continue to appear on the market. Many claim to offer improvements over older designs but such assertions are difficult to validate when there is no agreement as to how such implants should be tested in the laboratory - or even if such testing is necessary.
>In order to permit appropriate laboratory testing of all types of reverse shoulder prostheses a unique, multi-station test rig has been designed by Dr Simon Smith and built under the direction of Professor Tom Joyce in the School Of Mechanical and Systems Engineering at Newcastle University, with help from the Thorite.
>The new test rig is capable of applying motion in three axes to test prostheses. Known as the Newcastle Shoulder Wear Simulator, it uses three Thorite-supplied Norgren pneumatic cylinders with integral position encoders to move five prosthetic shoulder joint units simultaneously in the flexion-extension, abduction-adduction (arm raising and lowering) and internal-external rotation axes.
>Axial loading is applied to each artificial shoulder joint using an SMC pneumatic cylinder.