ASTM F1747-96

1.1 This test method covers the procedures for determining the stiffness and strength of external fixator joints under axial loads and bending moments.

1.2 Depending on its design and its use in the overall construct, the joint of an external fixator needs to transmit one or more components of loading (tension, compression, torsion, or bending, or all of these) between the elements it grips (anchorage elements or bridge elements), without either itself or its gripping interface(s) undergoing either permanent deformation or excessive elastic deformation.

1.3 This test method also covers procedures for determining the range of adjustability in degrees of freedom for which the joint's configuration can be adjusted by the user, and procedures for determining the joint's range of motion in degrees of freedom for which motion is permitted if the fixator is unlocked.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.