Standard materials for middle clavicle implants are limited to Titanium and Stainless Steel; their high Young’s Modulus promotes stress shielding, which causes complications such as malunion or implant failure. This study investigates alternative materials, Cobalt Chromium, Polyether ether ketone (PEEK), Magnesium, and Polylactic Acid (PLA), along with the standard materials, to understand their stress distributions, assess the likelihood of stress shielding, and evaluate their viability through the use of ANSYS 2025 R1 Finite Element Analysis (FEA). The materials are tested with four plate variations: Superior Plate, Anteroinferior Plate, Thin Dual Plate, and Thick Dual Plate, subjected to a simultaneous load of 100 N compressive, 100 N bending, and 1 Nm torsional, and were compared according to their maximum von Mises Stresses in plate, bone, and fracture line. High Young’s Modulus materials (Titanium, Stainless Steel, and Cobalt Chromium) had maximum von Mises plate stresses ranging from 200 to 265 MPa. In contrast, lower Young’s Modulus materials (Magnesium, PEEK, and PLA) showed maximum von Mises stresses of only around 115 to 170 MPa. PLA showed insufficient material strength, with bone stresses being around 30 MPa greater than plate stresses. PEEK showed viability but failed in material strength for the superior plate variation, as its maximum von Mises Stress of 168.13 MPa exceeded the yield strength of 125 MPa. Magnesium showed the best results, with bone and plate stresses near each other, and passed all viability criteria, demonstrating good material strength and a low risk of stress shielding. The results reinforce the use of Titanium and Stainless Steel as standards, show the viability of Cobalt Chromium for patients needing increased stability but with risks of stress shielding, demonstrate Magnesium for bioabsorbability and low stress shielding risk, suggest PEEK for low load applications, and reveal that PLA has insufficient strength. The study provides a comprehensive comparison of different materials with various variations, which provides a foundation for future studies to analyze material behavior.
Reyes et al. (Thu,) studied this question.