Shoulder prostheses tensile testing

Case study

Shoulder joint prosthesis testing fixtures close-up montage

Shoulder prosthesis testing system installation

Solution

Software-controlled twin-column test stand
Custom fixture to support and orient the shoulder joint

Benefits

Bespoke solution to meet the exact anatomy and movement
Repeatable test procedure
Cyclic testing thoroughly evaluates the design functionality and durability

I am very pleased with both the service from Mecmesin and the MultiTest 10-x test system and would recommend it for testing many of the aspects of soft tissue repair in orthopaedics. The MultiTest 10-x is easy-to-use and ideal for this application, of testing the fixation of bones and tendons around a prosthesis inserted for fracture of the shoulder.

Mr Keith Borowsky, Orthopaedic Surgeon
University of Brighton Medical School

Requirement

Mr Keith Borowsky, an eminent orthopaedic surgeon at the University of Brighton Medical School is developing a new orthopaedic prosthesis for shoulder reconstruction. Shoulder prostheses are used to replace shoulders fractured in falls in the elderly, and occasionally following high-energy motor vehicle collisions or by direct violent trauma. They can also be applied in other situations where shoulder replacement is required e.g. arthritic patients.

The prostheses need to be tested to ensure that they attach correctly to the surrounding bones and tendons, reliably replicating the anatomical structure of a shoulder. This research will ensure that patients retain a good degree of strength and mobility in their replacement shoulder joints.

Solution

Mr Borowsky is using a MultiTest 10-x twin-column, console-controlled force testing system to replicate patient’s mobility and movement over a period of time. During the test the prosthesis is attached to a cadaver and the MultiTest 10-x is used to pull the prosthesis repair site at a constant rate of tension, in the line of pull of normal muscles. The cyclic testing feature is used for this application, to exercise the prosthesis between different load limits for 999 times. The results from these cyclic tests give a measurable indication of the strength of the different shoulder replacement prostheses.

Mecmesin’s Emperor™ Lite data acquisition software is then used to store and manage the test data. The MultiTest 10-x combined with Emperor™ Lite has provided the University of Brighton Medical School with a cost-effective solution to their application in comparison with other materials testers on the market.