In Situ Measurement of Micromotion of Acetabular Cup Subjected to Cyclic Load

This study aims to address these challenges by evaluating the displacement and interfacial damage of acetabular components with auxetic inner structures under cyclic loading conditions. Aseptic loosening of the acetabular cup is one of the primary causes of implant failure in hip replacements. However, assessing the damage behavior of implants in vivo remains a significant challenge, particularly when evaluating implant displacement and interfacial damage. A cantilever device for displacement measurements was designed and calibrated using a laser displacement sensor. The cantilever device successfully measured the displacement of the acetabular cup by monotonic and cyclic loading up to-2.3kN. Both AE sensors and cantilever devices could measure the increasing displacement in both the rotational and embedding directions. Finally, the loosening mechanism of the acetabular cup with an auxetic texture was discussed.