1
|
Zhu Y, Babazadeh-Naseri A, Brake MRW, Akin JE, Li G, Lewis VO, Fregly BJ. Evaluation of finite element modeling methods for predicting compression screw failure in a custom pelvic implant. Front Bioeng Biotechnol 2024; 12:1420870. [PMID: 39234264 PMCID: PMC11372789 DOI: 10.3389/fbioe.2024.1420870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Accepted: 08/05/2024] [Indexed: 09/06/2024] Open
Abstract
Introduction: Three-dimensional (3D)-printed custom pelvic implants have become a clinically viable option for patients undergoing pelvic cancer surgery with resection of the hip joint. However, increased clinical utilization has also necessitated improved implant durability, especially with regard to the compression screws used to secure the implant to remaining pelvic bone. This study evaluated six different finite element (FE) screw modeling methods for predicting compression screw pullout and fatigue failure in a custom pelvic implant secured to bone using nine compression screws. Methods: Three modeling methods (tied constraints (TIE), bolt load with constant force (BL-CF), and bolt load with constant length (BL-CL)) generated screw axial forces using functionality built into Abaqus FE software; while the remaining three modeling methods (isotropic pseudo-thermal field (ISO), orthotropic pseudo-thermal field (ORT), and equal-and-opposite force field (FOR)) generated screw axial forces using iterative physics-based relationships that can be implemented in any FE software. The ability of all six modeling methods to match specified screw pretension forces and predict screw pullout and fatigue failure was evaluated using an FE model of a custom pelvic implant with total hip replacement. The applied hip contact forces in the FE model were estimated at two locations in a gait cycle. For each of the nine screws in the custom implant FE model, likelihood of screw pullout failure was predicted using maximum screw axial force, while likelihood of screw fatigue failure was predicted using maximum von Mises stress. Results: The three iterative physics-based modeling methods and the non-iterative Abaqus BL-CL method produced nearly identical predictions for likelihood of screw pullout and fatigue failure, while the other two built-in Abaqus modeling methods yielded vastly different predictions. However, the Abaqus BL-CL method required the least computation time, largely because an iterative process was not needed to induce specified screw pretension forces. Of the three iterative methods, FOR required the fewest iterations and thus the least computation time. Discussion: These findings suggest that the BL-CL screw modeling method is the best option when Abaqus is used for predicting screw pullout and fatigue failure in custom pelvis prostheses, while the iterative physics-based FOR method is the best option if FE software other than Abaqus is used.
Collapse
Affiliation(s)
- Yuhui Zhu
- Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Ata Babazadeh-Naseri
- Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Matthew R W Brake
- Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - John E Akin
- Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Geng Li
- Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Valerae O Lewis
- Department of Orthopedic Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Benjamin J Fregly
- Department of Mechanical Engineering, Rice University, Houston, TX, United States
| |
Collapse
|
2
|
Stolle J, Harper CM, Voegele KK, Najafi AR, Taheri M, MacBain J, Siegler S. A statistical analysis of human talar shape and bone density distribution. J Orthop Res 2024; 42:1780-1790. [PMID: 38483072 DOI: 10.1002/jor.25835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 02/16/2024] [Accepted: 02/26/2024] [Indexed: 07/04/2024]
Abstract
The shape of the talus, its internal structure, and its mechanical properties are important in determining talar behavior during loading, which may be significant for the design of surgical tools and implants. Although recent studies using statistical shape modeling have described quantitative talar external shape variation, no similar quantitative study exists to describe the density distribution of internal talar structure. The goal of this study is to quantify statistical variation in talar shape and density to benefit the design of talar implants. To this end, weight-bearing computed tomography (CT) scans of the ankle were collected in neutral, bilateral standing posture, and three-dimensional models were generated for each talus. Local density derived from the Hounsfield unit of each CT voxel was extracted. A weighted spherical harmonic analysis was performed to quantify the talar external shape. One hundred and seventy-nine volumes of interest were placed in the same relative position within each talus to quantify the talar density. Additionally, a finite element analysis (FEA) was conducted on a talus with both heterogeneous and homogeneous material properties to observe the effect of these properties on the stress and strain response. Significant differences were found in the talar density in sex and age, as well as in the stress and strain response between homogeneous and heterogeneous FEA. These differences show the importance of considering heterogeneity when examining the load response of tarsal bones.
Collapse
Affiliation(s)
- Jordan Stolle
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, Pennsylvania, USA
| | - Christine M Harper
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, New Jersey, USA
| | - Kristyn K Voegele
- Department of Geology, Rowan University School of Earth and Environment, Glassboro, New Jersey, USA
| | - Ahmad R Najafi
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, Pennsylvania, USA
| | - Mehrangiz Taheri
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, Pennsylvania, USA
| | - Joshua MacBain
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, Pennsylvania, USA
| | - Sorin Siegler
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, Pennsylvania, USA
| |
Collapse
|
3
|
Zhu Y, Babazadeh-Naseri A, Dunbar NJ, Brake MRW, Zandiyeh P, Li G, Leardini A, Spazzoli B, Fregly BJ. Finite element analysis of screw fixation durability under multiple boundary and loading conditions for a custom pelvic implant. Med Eng Phys 2023; 111:103930. [PMID: 36792235 DOI: 10.1016/j.medengphy.2022.103930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022]
Abstract
Despite showing promising functional outcomes for pelvic reconstruction after sarcoma resection, custom-made pelvic implants continue to exhibit high complication rates due to fixation failures. Patient-specific finite element models have been utilized by researchers to evaluate implant durability. However, the effect of assumed boundary and loading conditions on failure analysis results of fixation screws remains unknown. In this study, the postoperative stress distributions in the fixation screws of a state-of-the-art custom-made pelvic implant were simulated, and the risk of failure was estimated under various combinations of two bone-implant interaction models (tied vs. frictional contact) and four load cases from level-ground walking and stair activities. The study found that the average weighted peak von Mises stress could increase by 22-fold when the bone-implant interactions were modeled with a frictional contact model instead of a tied model, and the likelihood of fatigue and pullout failure for each screw could change dramatically when different combinations of boundary and loading conditions were used. The inclusion of additional boundary and loading conditions led to a more reliable analysis of fixation durability. These findings demonstrated the importance of simulating multiple boundary conditions and load cases for comprehensive implant design evaluation using finite element analysis.
Collapse
Affiliation(s)
- Yuhui Zhu
- Department of Mechanical Engineering, Rice University, Houston, Texas, USA
| | | | - Nicholas J Dunbar
- Department of Mechanical Engineering, Rice University, Houston, Texas, USA
| | - Matthew R W Brake
- Department of Mechanical Engineering, Rice University, Houston, Texas, USA
| | - Payam Zandiyeh
- Department of Orthopedic Surgery, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Geng Li
- Department of Mechanical Engineering, Rice University, Houston, Texas, USA
| | - Alberto Leardini
- Movement Analysis Laboratory, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Benedetta Spazzoli
- Clinica Ortopedica III, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Benjamin J Fregly
- Department of Mechanical Engineering, Rice University, Houston, Texas, USA.
| |
Collapse
|
4
|
Vega MM, Li G, Shourijeh MS, Ao D, Weinschenk RC, Patten C, Font-Llagunes JM, Lewis VO, Fregly BJ. Computational evaluation of psoas muscle influence on walking function following internal hemipelvectomy with reconstruction. Front Bioeng Biotechnol 2022; 10:855870. [PMID: 36246391 PMCID: PMC9559731 DOI: 10.3389/fbioe.2022.855870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 09/01/2022] [Indexed: 11/13/2022] Open
Abstract
An emerging option for internal hemipelvectomy surgery is custom prosthesis reconstruction. This option typically recapitulates the resected pelvic bony anatomy with the goal of maximizing post-surgery walking function while minimizing recovery time. However, the current custom prosthesis design process does not account for the patient's post-surgery prosthesis and bone loading patterns, nor can it predict how different surgical or rehabilitation decisions (e.g., retention or removal of the psoas muscle, strengthening the psoas) will affect prosthesis durability and post-surgery walking function. These factors may contribute to the high observed failure rate for custom pelvic prostheses, discouraging orthopedic oncologists from pursuing this valuable treatment option. One possibility for addressing this problem is to simulate the complex interaction between surgical and rehabilitation decisions, post-surgery walking function, and custom pelvic prosthesis design using patient-specific neuromusculoskeletal models. As a first step toward developing this capability, this study used a personalized neuromusculoskeletal model and direct collocation optimal control to predict the impact of ipsilateral psoas muscle strength on walking function following internal hemipelvectomy with custom prosthesis reconstruction. The influence of the psoas muscle was targeted since retention of this important muscle can be surgically demanding for certain tumors, requiring additional time in the operating room. The post-surgery walking predictions emulated the most common surgical scenario encountered at MD Anderson Cancer Center in Houston. Simulated post-surgery psoas strengths included 0% (removed), 50% (weakened), 100% (maintained), and 150% (strengthened) of the pre-surgery value. However, only the 100% and 150% cases successfully converged to a complete gait cycle. When post-surgery psoas strength was maintained, clinical gait features were predicted, including increased stance width, decreased stride length, and increased lumbar bending towards the operated side. Furthermore, when post-surgery psoas strength was increased, stance width and stride length returned to pre-surgery values. These results suggest that retention and strengthening of the psoas muscle on the operated side may be important for maximizing post-surgery walking function. If future studies can validate this computational approach using post-surgery experimental walking data, the approach may eventually influence surgical, rehabilitation, and custom prosthesis design decisions to meet the unique clinical needs of pelvic sarcoma patients.
Collapse
Affiliation(s)
- Marleny M. Vega
- Rice Computational Neuromechanics Lab, Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Geng Li
- Rice Computational Neuromechanics Lab, Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Mohammad S. Shourijeh
- Rice Computational Neuromechanics Lab, Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Di Ao
- Rice Computational Neuromechanics Lab, Department of Mechanical Engineering, Rice University, Houston, TX, United States
| | - Robert C. Weinschenk
- Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Carolynn Patten
- Biomechanics, Rehabilitation, and Integrative Neuroscience (BRaIN) Lab, UC Davis School of Medicine, Sacramento, CA, United States
- UC Davis Center for Neuroengineering and Medicine, University of California, Davis, CA, United States
- VA Northern California Health Care System, Martinez, CA, United States
| | - Josep M. Font-Llagunes
- Biomechanical Engineering Lab, Department of Mechanical Engineering and Research Centre for Biomedical Engineering, Universitat Politècnica de Catalunya, Barcelona, Spain
- Health Technologies and Innovation, Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Spain
| | - Valerae O. Lewis
- Department of Orthopaedic Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Benjamin J. Fregly
- Rice Computational Neuromechanics Lab, Department of Mechanical Engineering, Rice University, Houston, TX, United States
| |
Collapse
|
5
|
Henyš P, Vořechovský M, Stebel J, Kuchař M, Exner P. From computed tomography to finite element space: A unified bone material mapping strategy. Clin Biomech (Bristol, Avon) 2022; 97:105704. [PMID: 35849946 DOI: 10.1016/j.clinbiomech.2022.105704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 03/23/2022] [Accepted: 06/07/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND The spatially varying mechanical properties in finite element models of bone are most often derived from bone density data obtained via quantitative computed tomography. The key step is to accurately and efficiently map the density given in voxels to the finite element mesh. METHODS The density projection is first formulated in least-squares terms and then discretized using a continuous and discontinuous variant of the finite element method. Both discretization variants are compared with the nodal and element approaches known from the literature. FINDINGS In terms of accuracy in the L2 norm, energy distance and efficiency, the discontinuous zero-order variant appears to be the most advantageous. The proposed variant sufficiently preserves the spectrum of density at the edges, while keeping computational cost low. INTERPRETATION The continuous finite element method is analogous to the nodal formulation in the literature, while the discontinuous finite element method is analogous to the element formulation. The two variants differ in terms of implementation, computational cost and ability to preserve the density spectrum. These differences cannot be described and measured by known indirect methods from the literature.
Collapse
Affiliation(s)
- Petr Henyš
- Institute of New Technologies and Applied Informatics, Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 1402/2, 46117 Liberec, Czech Republic
| | - Miroslav Vořechovský
- Institute of Structural Mechanics, Faculty of Civil Engineering, Brno University of Technology, Veveří 331/95, 60200 Brno, Czech Republic
| | - Jan Stebel
- Institute of New Technologies and Applied Informatics, Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 1402/2, 46117 Liberec, Czech Republic
| | - Michal Kuchař
- Department of Anatomy, Faculty of Medicine in Hradec Králové, Charles University, Šimkova 870, 50003, Hradec Králové, Czech Republic
| | - Pavel Exner
- Institute of New Technologies and Applied Informatics, Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 1402/2, 46117 Liberec, Czech Republic.
| |
Collapse
|