Determining the Failure Potential of Total Hip Arthroplasty in Frontal Motor Vehicle Impacts: An Interdisciplinary Approach

Due to the ever increasing number of total hip arthroplasties performed every year, the loading conditions typically experienced by a patient during the activities of everyday living must be accounted for in both the design and testing of an artificial joint (5). The probability of implant failure must constantly be addressed. Further, knowledge of these loading conditions may be applied to accidental events such as motor vehicle impacts to determine the potential for failure of a total hip arthroplasty during such “abnormal” occurrences. Specifically, when considering loading conditions experienced during a motor vehicle accident, one could determine if the failure of an implant was due to the inadequacy of the implant, the failure of the bone around the implant, or a pre-existing degraded condition in the implant-bone construct. The goal of this presentation is to provide an outline of the types of data and analyses that are necessary to determine the nature of a failed total hip arthroplasty subsequent to a frontal motor vehicle impact. These include data from the patient’s medical records, biomechanical properties of bone, structural and material properties of implant materials, and accident vehicle dynamics. This information may then be consolidated and analyzed in a flowchart fashion to provide a most probable cause of implant failure.