ASTM F1378 sets specifications and guidelines for the mechanical testing of shoulder prostheses for total or hemiarthroplasty. Shoulder prostheses have a functional design to replace and mimic the function articulated by glenoid and humeral components. This function can significantly improve the quality of life and mobility of patients with shoulder impairments.
Shoulder replacements are not as common as lower extremity replacements, nor do shoulder prosthetics have the same wear test requirements as hip or knee prosthetics. They must adhere to ASTM guidelines that consider the dynamic kinematic biology of shoulder mechanics and how they must endure regular wear to treat severe fractures, joint problems, or arthritis effectively. ASTM F1378 specifies mechanical strength, range of motion, and surface finish requirements for the prosthesis.
Testing includes fatigue assessments, glenoid loosening and glenoid shear, and shoulder constraint evaluations. The unique biomechanics of the shoulder include joint stability, muscle balance, and coordination. Testing prostheses against in vitro elements such as balance, ligamentous restraint, joint geometry, and bone structure is essential to determine a design’s clinical viability.
In order to be considered for approval from the FDA, any prosthetic design must adhere to ASTM standards. F1378 establishes the mechanical properties of the implant in conjunction with supporting bone structure. This specification includes modular prostheses. However, devices intended for custom applications are not covered under ASTM F1378.