A Dual Biomechanical Failure: Exeter Stem and Pubic Rami Insufficiency Fracture, following Hybrid Total Hip Arthroplasty

Abstract

Introduction. Incidence of Exeter stem fracture is extremely uncommon. Pubic rami insufficiency fractures following arthroplasty are also rare. To our knowledge no cases of spontaneous stem failure with previous insufficiency fractures have yet been reported. Case Presentation. This report describes a case of spontaneous fracture through a cemented Exeter stem in a 66-year-old patient who had previously undergone a hybrid total hip replacement and was found to have bifocal pubic rami insufficiency fractures. The patient presented 18-year postprimary surgery with spontaneous fracture of the middle third of the cemented femoral stem and adjacent proximal femur. Conclusion. This report demonstrates a unique case of Exeter stem fracture with previous pelvic insufficiency fractures. The case adds to the rare occurrences of Exeter stem failure in the literature and highlights the risk of potential insufficiency fractures in patients undergoing total hip replacement.

Finite Element Analysis of Proximal Cement Fixation in Total Hip Arthroplasty

“…It was a partially cemented stem, known as a hybrid model, with proximal cementation and cranial press fit. Similar studies describing the performance of proximal fixation referred to the hybrid stem model (Pennington et al, 2013;Samra and Paliobeis, 2015;Valle et al, 2016;Wangen et al, 2017;Zhang et al, 2017;Jonas et al, 2019;Nawfal et al, 2020). In this study, the proposed proximal fixation was applied to the fully cemented implant model.…”