Finite element study of functionally graded porous femoral stems incorporating body‐centered cubic structure

Tarlochan

et al. 2020

J Mater Sci: Mater Med

Self Cite

The current study is proposing a design envelope for porous Ti-6Al-4V alloy femoral stems to survive under fatigue loads. Numerical computational analysis of these stems with a body-centered-cube (BCC) structure is conducted in ABAQUS. Femoral stems without shell and with various outer dense shell thicknesses (0.5, 1.0, 1.5, and 2 mm) and inner cores (porosities of 90, 77, 63, 47, 30, and 18%) are analyzed. A design space (envelope) is derived by using stem stiffnesses close to that of the femur bone, maximum fatigue stresses of 0.3σys in the porous part, and endurance limits of the dense part of the stems. The Soderberg approach is successfully employed to compute the factor of safety Nf > 1.1. Fully porous stems without dense shells are concluded to fail under fatigue load. It is thus safe to use the porous stems with a shell thickness of 1.5 and 2 mm for all porosities (18–90%), 1 mm shell with 18 and 30% porosities, and 0.5 mm shell with 18% porosity. The reduction in stress shielding was achieved by 28%. Porous stems incorporated BCC structures with dense shells and beads were successfully printed.

Section: Introductionmentioning

confidence: 99%

A novel design, analysis and 3D printing of Ti-6Al-4V alloy bio-inspired porous femoral stem

Tarlochan

et al. 2020

J Mater Sci: Mater Med

Self Cite

Front. Bioeng. Biotechnol.

“…Numerous studies have shown that micro-motion between the femoral stem and bone interface is negatively correlated with the stiffness of the femoral stem (Alkhatib et al, 2019b). The main purpose of designing stems with a porous internal structure is to reduce stiffness to avoid stress shielding of the bone, but the reduced stiffness may also cause excessive interface micromotion.…”

Section: Promotion Of Bone Ingrowthmentioning

confidence: 99%

Femoral Stems With Porous Lattice Structures: A Review

Liu

Wang

Zhang

et al. 2021

Cementless femoral stems are prone to stress shielding of the femoral bone, which is caused by a mismatch in stiffness between the femoral stem and femur. This can cause bone resorption and resultant loosening of the implant. It is possible to reduce the stress shielding by using a femoral stem with porous structures and lower stiffness. A porous structure also provides a secondary function of allowing bone ingrowth, thus improving the long-term stability of the prosthesis. Furthermore, due to the advent of additive manufacturing (AM) technology, it is possible to fabricate femoral stems with internal porous lattices. Several review articles have discussed porous structures, mainly focusing on the geometric design, mechanical properties and influence on bone ingrowth. However, the safety and effectiveness of porous femoral stems depend not only on the characteristic of porous structure but also on the macro design of the femoral stem; for example, the distribution of the porous structure, the stem geometric shape, the material, and the manufacturing process. This review focuses on porous femoral stems, including the porous structure, macro geometric design of the stem, performance evaluation, research methods used for designing and evaluating the femoral stems, materials and manufacturing techniques. In addition, this review will evaluate whether porous femoral stems can reduce stress shielding and increase bone ingrowth, in addition to analyzing their shortcomings and related risks and providing ideas for potential design improvements.

“…Sami E. Alkhatib et al of Qatar University, Doha, Qatar investigated by three‐dimensional finite‐element models the use of homogeneous porous (HGP) and functionally graded porous (FGP) stems incorporating body‐centered cubic (BCC) structures as an alternative to the dense stems. Three levels of porosities (20%, 50%, and 80%) were modeled in HGP and FGP stems.…”

Section: Orthopedic Supportmentioning

confidence: 99%

Artificial Organs 2019: A year in review

Malchesky¹

2020

Artificial Organs

In this Editor’s Review, articles published in 2019 are organized by category and summarized. These provide a brief reflection of the research and progress in artificial organs intended to advance and better human life while providing insight for continued application of these technologies and methods. Artificial Organs continues in the original mission of its founders “to foster communications in the field of artificial organs on an international level.” Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. Peer‐reviewed Special Issues this year included contributions from the 14th International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion edited by Dr Akif Undar, and the 26th Congress of the International Society for Mechanical Circulatory Support edited by Dr Minoru Ono and Dr Francesco Moscato. Additionally, important editorials highlighted the need for sustainability in hemodialysis, challenges and opportunities in mechanical circulatory support, progress in artificial pancreas development, historical perspectives on ventilators and dialysis, tissue engineering for cardiac support, and regional updates from India and China. Our Pioneer Series continues to highlight the many researchers who created this field of study. This year we debuted a new series entitled “Recent Progress in Artificial Organs” prepared by Vakhtang Tchantchaleishvili and Elizabeth Maynes of Thomas Jefferson University, Philadelphia, PA, USA. This series highlights recent advances and new developments in the field. We take this time also to express our gratitude to our authors for contributing their work to this journal. We offer our very special thanks to our reviewers who give so generously of their time and expertise to review, critique, and especially provide meaningful suggestions to the author’s work. Without our dedicated expert reviewers, the quality expected from such a journal would not be possible. We also express our special thanks to our Publisher, John Wiley & Sons, for their expert attention and support in the production Artificial Organs. We look forward to reporting further advances in the coming years.