Angled orthopaedic fixation devices or hip compression screws are used to treat fractures in the metaphyseal areas of long bones. Loading creates a compression bending load at the angled portion, which must be evaluated for strength and stiffness by researchers when comparing materials and designs.  Surgeons use this information to predict performance Fatigue life over a specific time or loading range. For these reasons, the test fixture must simulate compressive loads experienced by the angled portion of the plate as a result of body weight.

Testing is based on standard ASTM F384 - Standard Specifications and Test Methods for Metallic Angled Orthopedic Fracture Fixation Devices. For static testing, a ramped compression load is applied until the fixation device plastically deforms or a set deflection is reached. The objective is to determine the static bending stiffness of the plate. Four-point bending and fatigue testing, using an ElectroPuls™ Test Instrument is necessary to accurately evaluate the fixation device. The fixture is designed to work with or without a saline bath and can be adapted to suit a variety of specimen sizes and geometries. 

We recommend that you review the standard to fully understand its requirements.

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