The Biomechanics of a Validated Finite Element Model of Stress Shielding in a Novel Hybrid Total Knee Replacement

This study presents a semi-automatic framework to create subject-specific total knee replacement finite element models, which can be used to analyze locomotion patterns and evaluate knee dynamics. In recent years, much scientific attention was attracted to pre-clinical optimization of customized total knee replacement operations through computational modeling to minimize post-operational adverse effects. However, the time-consuming and laborious process of developing a subject-specific finite element model poses an obstacle to the latter. One of this work's main goals is to automate the finite element model development process, which speeds up the proposed framework and makes it viable for practical applications. This pipeline's reliability was ratified by developing and validating a subject-specific total knee replacement model based on the 6th SimTK Grand Challenge data set. The model was validated by analyzing contact pressures on the tibial insert in relation to the patient's gait and analysis of tibial contact forces, which were found to be in accordance with the ones provided by the Grand Challenge data set. Subsequently, a sensitivity analysis was carried out to assess the influence of modeling choices on tibial insert's contact pressures and determine possible uncertainties on the models produced by the framework. Parameters, such as the position of ligament origin points, ligament stiffness, reference strain, and implant-bone alignment were used for the sensitivity study. Notably, it was found that changes in the alignment of the femoral component in reference to the knee bones significantly affect the load distribution at the tibiofemoral joint, with an increase of 206.48% to be observed at contact pressures during 5° internal rotation. Overall, the models produced by this pipeline can be further used to optimize and personalize surgery by evaluating the best surgical parameters in a simulated manner before the actual surgery.

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Using Musculoskeletal Models to Estimate in vivo Total Knee Replacement Kinematics and Loads: Effect of Differences Between Models

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.703508 ◽

2021 ◽

Vol 9 ◽

Author(s):

Cristina Curreli ◽

Francesca Di Puccio ◽

Giorgio Davico ◽

Luca Modenese ◽

Marco Viceconti

Keyword(s):

Finite Element ◽

Knee Joint ◽

Total Knee Replacement ◽

Finite Element Model ◽

Knee Replacement ◽

Element Model ◽

Assessment Process ◽

Grand Challenge ◽

Total Knee

Total knee replacement (TKR) is one of the most performed orthopedic surgeries to treat knee joint diseases in the elderly population. Although the survivorship of knee implants may extend beyond two decades, the poor outcome rate remains considerable. A recent computational approach used to better understand failure modes and improve TKR outcomes is based on the combination of musculoskeletal (MSK) and finite element models. This combined multiscale modeling approach is a promising strategy in the field of computational biomechanics; however, some critical aspects need to be investigated. In particular, the identification and quantification of the uncertainties related to the boundary conditions used as inputs to the finite element model due to a different definition of the MSK model are crucial. Therefore, the aim of this study is to investigate this problem, which is relevant for the model credibility assessment process. Three different generic MSK models available in the OpenSim platform were used to simulate gait, based on the experimental data from the fifth edition of the “Grand Challenge Competitions to Predict in vivo Knee Loads.” The outputs of the MSK analyses were compared in terms of relative kinematics of the knee implant components and joint reaction (JR) forces and moments acting on the tibial insert. Additionally, the estimated knee JRs were compared with those measured by the instrumented knee implant so that the “global goodness of fit” was quantified for each model. Our results indicated that the different kinematic definitions of the knee joint and the muscle model implemented in the different MSK models influenced both the motion and the load history of the artificial joint. This study demonstrates the importance of examining the influence of the model assumptions on the output results and represents the first step for future studies that will investigate how the uncertainties in the MSK models propagate on disease-specific finite element model results.

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Finite element evaluation of the newest ISO testing standard for polyethylene total knee replacement liners

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411918770700 ◽

2018 ◽

Vol 232 (6) ◽

pp. 545-552 ◽

Cited By ~ 8

Author(s):

Steven P Mell ◽

Spencer Fullam ◽

Markus A Wimmer ◽

Hannah J Lundberg

Keyword(s):

Finite Element ◽

Total Knee Replacement ◽

Knee Replacement ◽

External Rotation ◽

Articular Surface ◽

Element Model ◽

International Standards ◽

Wear Testing ◽

Contact Conditions ◽

Total Knee

Current treatment for end-stage osteoarthritis is total knee replacement. Given that the number of total knee replacement surgeries is expected to approach 3.48 million by 2030, understanding long-term failure is important. One of the preclinical tests for total knee replacements is carried out using mechanical wear testing under generic walking conditions. Used for this purpose is the International Standards Organization’s generic walking profile. Recently this standard was updated by reversing the direction of anterior/posterior translation and internal/external rotation. The effects of this change have not been investigated, and therefore, it is unknown if comparisons between wear tests utilizing the old and new version of the standard are valid. In this study, we used a finite element model along with a frictional energy–based wear model to compare the kinematic inputs, contact conditions, and wear from the older and newer versions of the ISO standard. Simulator-tested components were used to validate the computational model. We found that there were no visible similarities in the contact conditions between the old and new versions of the standard. The new version of the standard had a lower wear rate but covered a larger portion of the articular surface. Locations of wear also varied considerably. The results of the study suggest that major differences between the old and new standard exist, and therefore, historical wear results should be compared with caution to newly obtained results.

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The Effect of Micro Grooving on Goat Total Knee Replacement: A Finite Element Study

10.1115/1.0004448v ◽

2021 ◽

Author(s):

Morshed Khandaker ◽

Onur Can Kalay ◽

Fatih Karpat ◽

Amgad Haleem ◽

Wendy Williams ◽

...

Keyword(s):

Finite Element ◽

Total Knee Replacement ◽

Knee Replacement ◽

Finite Element Study ◽

Micro Grooving ◽

Total Knee ◽

Element Study

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Development of a Tibial Slider to Evaluate and Validate a Finite Element Model for Friction in Total Knee Implants

10.1115/imece2000-2550 ◽

2000 ◽

Author(s):

Michael D. Nowak ◽

Kenneth Shaw ◽

Courtland Lewis

Keyword(s):

United States ◽

Finite Element ◽

Knee Replacement ◽

Severe Pain ◽

Element Model ◽

The United States ◽

Loss Of Function ◽

Articular Surfaces ◽

Joint Disorder ◽

Total Knee

Abstract More than 200,000 people in the United States annually undergo knee replacement as a means of diminishing pain and stiffness and restoring mobility, and the number is expected to increase with further advancements in joint replacement procedures [Duke, 1999]. Total knee replacement is performed on people with severe degenerative joint disorder such as osteoarthritis in which the articular surfaces of the knee deteriorate, leading to severe pain, limitation or loss of function and/or deformity of the joint.

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A subject-specific finite element musculoskeletal framework for mechanics analysis of a total knee replacement

Journal of Biomechanics ◽

10.1016/j.jbiomech.2018.07.008 ◽

2018 ◽

Vol 77 ◽

pp. 146-154 ◽

Cited By ~ 16

Author(s):

Liming Shu ◽

Ko Yamamoto ◽

Jiang Yao ◽

Prabhav Saraswat ◽

Yao Liu ◽

...

Keyword(s):

Finite Element ◽

Total Knee Replacement ◽

Knee Replacement ◽

Subject Specific ◽

Mechanics Analysis ◽

Total Knee

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The Effect of Micro Grooving on Goat Total Knee Replacement: A Finite Element Study

Volume 5: Biomedical and Biotechnology ◽

10.1115/imece2020-24136 ◽

2020 ◽

Author(s):

Morshed Khandaker ◽

Onur Can Kalay ◽

Fatih Karpat ◽

Amgad Haleem ◽

Wendy Williams ◽

...

Keyword(s):

Finite Element ◽

Total Knee Replacement ◽

Knee Replacement ◽

Joint Replacement ◽

Mechanical Performance ◽

The United States ◽

Cement Interface ◽

Bonding Failure ◽

Total Knee ◽

Joint Prostheses

Abstract A method to improve the mechanical fixation of a total knee replacement (TKR) implant is clinically important and is the purpose of this study. More than one million joint replacement procedures are performed in people each year in the United States, and experts predict the number to increase six-fold by the year 2030. Whether cemented or uncemented, joint prostheses may destabilize over time and necessitate revision. Approximately 40,000 hip arthroplasty surgeries have to be revised each year and the rate is expected to increase by approximately 140% (and by 600% for total knee replacement) over the next 25 years. In veterinary surgery, joint replacement has a long history and the phenomenon of surgical revision is also well recognized. For the betterment of both people and animals, improving the longevity of arthroplasty devices is of the utmost clinical importance, and towards that end, several strategies are under investigation. One approach that we explore in the present research is to improve the biomechanical performance of cemented implant systems by altering the implant surface architecture in a way that facilitates its cement bonding capacity. Beginning with the Charnley system, early femoral stems were polished smooth, but a number of subsequent designs have featured a roughened surface — created with bead or grit blasting — to improve cement bonding. Failure at the implant-cement interface remains an issue with these newer designs, leading us to explore in this present research an alternate, novel approach to surface alteration — specifically, laser microgrooving. This study used various microgrooves architectures that is feasible using a laser micromachining process on a tibia tray (TT) for the goat TKR. Developing the laser microgrooving (LM) procedure, we hypothesized feasibility in producing parallel microgrooves of precise dimensions and spacing on both flat and round metallic surfaces. We further hypothesized that laser microgrooving would increase surface area and roughness of the cement interface of test metallic implants and that such would translate into an improved acute mechanical performance as assessed in vitro under both static and cyclic loads. The objective was to develop a computational model to determine the effect of LIM on the tibial tray to the mechanical stimuli distributions from implant to bone using the finite element method. This study designed goat TT 3D solid model from a computer topography (CT) images, out of which three different laser microgrooves were engraved on TT sample by varying depth, height and space between two adjacent grooves. The simulation test results concluded that microgrooves acchitecures positively influence microstrain behavior around the implant/bone interfaces. There is a higher amount of strain observed for microgroove implant/bone samples compared to non-groove implant/bone samples. Thus, the laser-induced microgrooves have the potential to be used clinically in TKR components.

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