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RESEARCH ARTICLE
Integrated 3D printing of cementless CoCrMo femoral condyles optimizes trabecular surfaces and material performance
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1 Suzhou Microport Orthorecon Co., Ltd., Suzhou, Jiangsu,
China
2 School of Health Science and Engineering, University of Shanghai for Science & Technology, Shanghai,
China
3 Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA,
United States of America
4 Miracle Point Global LLC, Irvine, CA,
United States of America
†These authors contributed equally to this work.
IJB, 025380389 https://doi.org/10.36922/IJB025380389
Received: 19 September 2025 | Accepted: 3 November 2025 | Published online: 11 November 2025
(This article belongs to the Special Issue 3D-Printed Biomedical Devices)
© 2025 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract
Conventional cementless femoral condyles in artificial knee systems are commonly manufactured by casting followed by a surface treatment using plasma spraying or metallic sintering. However, both techniques suffer from weak coating-substrate interfaces that contribute to early loosening and higher revision rates. To overcome this limitation, we employed integrated 3D printing (I3P), an additive manufacturing strategy based on laser powder bed fusion, to fabricate monolithic cobalt-chromium-molybdenum femoral condyles with trabecular-inspired porous architectures. Compared with cast-sintered counterparts, I3P substrates exhibited refined microstructures and superior mechanical performance after hot isostatic pressing, reaching a yield strength of 637.33 MPa, ultimate tensile strength of 1140.00 MPa, and elongation of 27.33%. The I3P femoral condyles also showed enhanced fatigue resistance, withstanding 10 million cycles under a 3000 N load, and demonstrated improved wear behavior against ultrahigh-molecular-weight polyethylene liners. Furthermore, the trabecular-inspired lattice achieved stronger integration with the substrate than sintered coatings, with tensile and shear strengths of 56.09 and 49.97 MPa, respectively. Together, these findings establish I3P as a robust manufacturing strategy that integrates substrate and surface in a single step, enabling the production of durable, osteointegrative femoral condyles with significant potential to improve implant longevity and clinical outcomes in knee joint reconstruction.
Graphical abstract
Keywords
Additive manufacturing
Cementless femoral condyles
Cobalt-chromium-molybdenum alloys
Fatigue and wear resistance
Integrated 3D printing
Osteointegration
Total knee arthroplasty
Trabecular surface architecture
Funding
All materials, products, equipment, and funding for this study were provided by Suzhou Microport Orthorecon Co., Ltd.
Conflict of interest
J.W., Z.Z., T.Y., and W.W. are employees of Suzhou Microport Orthorecon, a subsidiary of MicroPort Orthopedics which produces and markets the commercial EVOLUTION femoral condyle implant examined in this study. B.Y.C. is an employee of MicroPort at the time of publication of this work.
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