New Failure Mechanism of Acetabular Constrained Liner: A Case Report.

Implant dislocation following total hip arthroplasty, particularly revision arthroplasty, remains a common postoperative complication. Constrained acetabular liners provide surgeons with an implant option that provides resistance to dislocation forces. These added forces, however, are transmitted to the implant materials and to the bone\endash implant interface, resulting in unique failure mechanisms. This case report presents two cases highlighting a previously unreported mechanism of failure of the Depuy Pinnacle ES constrained liner encountered during intraoperative implantation of the components (Journal of Surgical Orthopaedic Advances 28(1):68-73, 2019).