Metal Medical Bone Screws Axial pullout and Driving Torque, Self-Tapping Testing ASTM F543

ASTM F543 is a testing standard used in the biomedical industry that defines specifications for metallic medical bone screws. Bone screws are used in surgical procedures for securing implants, osteosynthesis devices, and fracture fixation plates to the skeletal system. In normal clinical use, a surgeon applies combined axial and torsional forces to implant a bone screw into the body. Bone screws are designated Class 2 FDA devices, requiring significant testing and analysis  of mechanical properties prior to approval and release.

ASTM F543-17 includes multiple annexes which stipulate the properties related to the functional use of bone screws and the axial torsion forces associated with their use. The standard also includes geometric specifications for the design of these devices. The annexes include both purely torsional as well as biaxial testing for a complete evaluation of these devices. Refer the Following Annex A1 ~A7. 

This specification provides performance considerations and standard test methods for measuring mechanical properties in torsion of metallic bone screws that are implanted into bone. These test methods may also be applicable to other screws besides those whose dimensions and tolerances are specified here. 

The following annexes are included:

Annex A1-Test Method for Determining the Torsional Properties of Metallic Bone Screws.

Annex A2-Test Method for Driving Torque of Medical Bone Screws.

Annex A3-Test Method for Determining the Axial Pullout Load of Medical Bone Screws.

Annex A4-Test Method for Determining the Self-Tapping Performance of Self-Tapping Medical Bone Screws.

Annex A5-Specifications for Type HA and Type HB Metallic Bone Screws.

Annex A6-Specifications for Type HC and Type HD Metallic Bone Screws.

Annex A7-Specifications for Metallic Bone Screw Drive Connections.

This specification is based, in part, upon ISO 5835, ISO 6475, and ISO 9268.

UnitedTest UT1050 series Metal bone screw torsion tester/ rotation torque test equipment can used to execute the ASTM F543 test.