How screw connections influence the primary stability of acetabular cups under consideration of different bone models

Gafar Adam Ahmed; Linda Auge; Jessica Loke; Carlos Alfonso Fonseca Ulloa; Christian Fölsch; Markus Rickert; Bernd Alexander Ishaque; Alexander Jahnke

doi:10.1016/j.jor.2020.05.020

How screw connections influence the primary stability of acetabular cups under consideration of different bone models

J Orthop. 2020 Jun 6:21:302-308. doi: 10.1016/j.jor.2020.05.020. eCollection 2020 Sep-Oct.

Authors

Gafar Adam Ahmed^{1

2}, Linda Auge¹, Jessica Loke¹, Carlos Alfonso Fonseca Ulloa¹, Christian Fölsch^{1

2}, Markus Rickert^{1

2}, Bernd Alexander Ishaque^{1

2}, Alexander Jahnke¹

Affiliations

¹ Laboratory for Biomechanics, Justus Liebig University Giessen, Klinikstrasse 29, 35392, Giessen, Germany.
² Department of Orthopaedics and Orthopaedic Surgery, University Hospital Giessen and Marburg (UKGM), Klinikstrasse 33, 35392, Giessen, Germany.

Abstract

Introduction: Good osteointegration of implants requires sufficient primary stability. Aim of this study was to examine the influence of screw fixation on the primary stability of press-fit cups.

Methods: Two press-fit acetabular cups were tested with regard to the influence and number of screws and their primary stability.

Results: For the relatively thin-walled Allofit®-S cup, an influence of the number of screws on the different forms of movement could be demonstrated.

Conclusions: We see a clear influence of the cup wall thickness on the elastic deformability and accordingly on the primary stability of the examined cups.

Keywords: Cementless; Cup component; Hip endoprosthetics; Primary stability; Screw connection.