Benedikt Schliemann1, Robert Seifert2, Christina Theisen2, Dominic Gehweiler3, Dirk Wähnert2, Martin Schulze2, Michael J Raschke2, Andre Weimann4. 1. Department of Trauma, Hand and Reconstructive Surgery, University Hospital Münster, Albert-Schweitzer-Campus 1, building W1, 48149, Münster, Germany. benedikt.schliemann@ukmuenster.de. 2. Department of Trauma, Hand and Reconstructive Surgery, University Hospital Münster, Albert-Schweitzer-Campus 1, building W1, 48149, Münster, Germany. 3. AO Research Institute Davos, Clavadelerstrasse 8, 7270, Davos, Switzerland. 4. OCP-Münster, Schaumburgstraße 1, 48145, Münster, Germany.
Abstract
INTRODUCTION: The high rigidity of metal implants may be a cause of failure after fixation of proximal humerus fractures. Carbon fiber-reinforced polyetheretherketone (PEEK) plates with a modulus similar to human cortical bone may help to overcome this problem. The present study assesses the biomechanical behavior of a PEEK plate compared with a titanium locking plate. MATERIALS AND METHODS: Unstable two- and three-part fractures were simulated in 12 pairs of cadaveric humeri and were fixed with either a PEEK or a titanium locking plate using a pairwise comparison. With an optical motion capture system, the stiffness, failure load, plate bending, and the relative motion at the bone-implant interface and at the fracture site were evaluated. RESULTS: The mean load to failure for two- and three-part fracture fixations was, respectively, 191 N (range 102-356 N) and 142 N (range 102-169 N) in the PEEK plate group compared with 286 N (range 191-395 N) and 258 N (range 155-366 N) in the titanium locking plate group. The PEEK plate showed significantly more bending in both the two- and three-part fractures (p < 0.05), an increased relative motion at the bone-implant interface and lower stiffness values (p < 0.05). CONCLUSION: In this biomechanical study on unstable proximal humerus fractures, fixation with a PEEK plate showed lower fixation strength and increased motion at the bone-implant interface compared with a titanium locking plate.
INTRODUCTION: The high rigidity of metal implants may be a cause of failure after fixation of proximal humerus fractures. Carbon fiber-reinforced polyetheretherketone (PEEK) plates with a modulus similar to human cortical bone may help to overcome this problem. The present study assesses the biomechanical behavior of a PEEK plate compared with a titanium locking plate. MATERIALS AND METHODS: Unstable two- and three-part fractures were simulated in 12 pairs of cadaveric humeri and were fixed with either a PEEK or a titanium locking plate using a pairwise comparison. With an optical motion capture system, the stiffness, failure load, plate bending, and the relative motion at the bone-implant interface and at the fracture site were evaluated. RESULTS: The mean load to failure for two- and three-part fracture fixations was, respectively, 191 N (range 102-356 N) and 142 N (range 102-169 N) in the PEEK plate group compared with 286 N (range 191-395 N) and 258 N (range 155-366 N) in the titanium locking plate group. The PEEK plate showed significantly more bending in both the two- and three-part fractures (p < 0.05), an increased relative motion at the bone-implant interface and lower stiffness values (p < 0.05). CONCLUSION: In this biomechanical study on unstable proximal humerus fractures, fixation with a PEEK plate showed lower fixation strength and increased motion at the bone-implant interface compared with a titanium locking plate.
Authors: Rony-Orijit Dey Hazra; Karol Szewczyk; Alexander Ellwein; Robert Blach; Gunnar Jensen; Andreas Kühnapfel; Helmut Lill; Mara Warnhoff Journal: Eur J Orthop Surg Traumatol Date: 2022-05-27
Authors: Y P Acklin; I Zderic; J A Inzana; S Grechenig; R Schwyn; R G Richards; B Gueorguiev Journal: Bone Joint Res Date: 2018-07-07 Impact factor: 5.853
Authors: Rony-Orijit Dey Hazra; Johanna Illner; Karol Szewczyk; Mara Warnhoff; Alexander Ellwein; Robert Maximillian Blach; Helmut Lill; Gunnar Jensen Journal: J Clin Med Date: 2022-01-14 Impact factor: 4.241