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Berardo A, Bonaldi L, Stecco C, Fontanella CG. Biomechanical properties of the human superficial fascia: Site-specific variability and anisotropy of abdominal and thoracic regions. J Mech Behav Biomed Mater 2024; 157:106637. [PMID: 38914036 DOI: 10.1016/j.jmbbm.2024.106637] [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: 04/15/2024] [Revised: 05/30/2024] [Accepted: 06/18/2024] [Indexed: 06/26/2024]
Abstract
Superficial fascia is a fibrofatty tissue found throughout the body. Initially described in relation to hernias, it has only recently received attention from the scientific community due to new evidence on its role in force transmission and structural integrity of the body. Considering initial difficulties in its anatomical identification, to date, a characterization of the superficial fascia through mechanical tests is still lacking. The mechanical properties of human superficial fasciae of abdominal and thoracic districts (back) of different subjects (n = 4) were then investigated, focusing on anisotropy and viscoelasticity. Experimental tests were performed on samples taken in two perpendicular directions according to body planes (cranio-caudal and latero-medial axes). Data collected from two different uniaxial tensile protocols, failure (i.e., ultimate tensile strength and strain at break, Young's modulus and toughness) and stress-relaxation (i.e., residual stress), were processed and then grouped for statistical analysis. Failure tests confirmed tissue anisotropy, revealing the stiffer nature of the latero-medial direction compared to the cranio-caudal one, for both the districts (with a ratio of the respective Young's moduli close to 2). Furthermore, the thoracic region exhibited significantly greater strength and resultant Young's modulus compared to the abdomen (with greater results along the latero-medial direction, such as 6.13 ± 3.11 MPa versus 0.85 ± 0.39 MPa and 24.87 ± 15.23 MPa versus 3.19 ± 1.62 MPa, respectively). On the contrary, both regions displayed similar strain at break (varying between 38 and 47%), with no clear dependence from the loading directions. Stress-relaxation tests highlighted the viscous behavior of the superficial fascia, with no significant differences in the stress decay between directions and districts (35-38% of residual stress after 300 s). All these collected results represent the starting point for a more in-depth knowledge of the mechanical characterization of the superficial fascia, which can have direct implications in the design, implementation, and effectiveness of site-specific treatments.
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Affiliation(s)
- Alice Berardo
- Department of Civil, Environmental and Architectural Engineering, University of Padova, 35131, Padova, Italy; Centre for Mechanics of Biological Materials, University of Padova, 35131, Padova, Italy
| | - Lorenza Bonaldi
- Department of Civil, Environmental and Architectural Engineering, University of Padova, 35131, Padova, Italy; Centre for Mechanics of Biological Materials, University of Padova, 35131, Padova, Italy.
| | - Carla Stecco
- Centre for Mechanics of Biological Materials, University of Padova, 35131, Padova, Italy; Department of Neuroscience, Institute of Human Anatomy, University of Padova, 35121, Padova, Italy
| | - Chiara Giulia Fontanella
- Centre for Mechanics of Biological Materials, University of Padova, 35131, Padova, Italy; Department of Industrial Engineering, University of Padova, 35131, Padova, Italy
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Kadiaké T, Lallemant M, Chambert J, Mottet N, Lejeune A, Jacquet E. Towards the biomechanical modelling of the behaviour of ex-vivo porcine perineal tissues. J Biomech 2024; 171:112175. [PMID: 38908107 DOI: 10.1016/j.jbiomech.2024.112175] [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: 01/09/2024] [Revised: 05/03/2024] [Accepted: 05/26/2024] [Indexed: 06/24/2024]
Abstract
The perineum is a layered soft tissue structure with mechanical properties that maintain the integrity of the pelvic floor. During childbirth, the perineum undergoes significant deformation that often results in tears of various degrees of severity. To better understand the mechanisms underlying perineal tears, it is crucial to consider the mechanical properties of the different tissues that make up the perineum. Unfortunately, there is a lack of data on the mechanical properties of the perineum in the literature. The objective of this study is to partly fill these gaps. Hence sow perineums were dissected and the five perineal tissues involved in tears were characterized by uniaxial tension tests: Skin, Vagina, External Anal Sphincter, Internal Anal Sphincter and Anal Mucosa. From our knowledge, this study is the first to investigate all these tissues and to design a testing protocol to characterize their material properties. Six material models were used to fit the experimental data and the correlation between experimental and predicted data was evaluated for comparison. As a result, even if the tissues are of different nature, the best correlation was obtained with the Yeoh and Martins material models for all tissues. Moreover, these preliminary results show the difference in stiffness between the tissues which indicates that they might have different roles in the structure. These obtained results will serve as a basis to design an improved experimental protocol for a more robust structural model of the porcine perineum that can be used for the human perineum to predict perineal tears.
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Affiliation(s)
- Tiguida Kadiaké
- Université de Franche-Comté, CNRS, Institut FEMTO-ST, Besançon, 25000, France
| | - Marine Lallemant
- Université de Franche-Comté, CNRS, Institut FEMTO-ST, Besançon, 25000, France; Service de gynécologie obstétrique, CHU Jean Minjoz, Besançon, 25000, France
| | - Jérôme Chambert
- Université de Franche-Comté, CNRS, Institut FEMTO-ST, Besançon, 25000, France
| | - Nicolas Mottet
- Service de gynécologie obstétrique, CHU Jean Minjoz, Besançon, 25000, France; Université de Franche-Comté, EA4662, laboratoire de Nanomédecine, Besançon, 25000, France
| | - Arnaud Lejeune
- Université de Franche-Comté, CNRS, Institut FEMTO-ST, Besançon, 25000, France
| | - Emmanuelle Jacquet
- Université de Franche-Comté, CNRS, Institut FEMTO-ST, Besançon, 25000, France.
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Tuset L, López-Cano M, Fortuny G, López JM, Herrero J, Puigjaner D. A virtual simulation approach to assess the effect of trocar-site placement and scar characteristics on the abdominal wall biomechanics. Sci Rep 2024; 14:3583. [PMID: 38351278 PMCID: PMC10864383 DOI: 10.1038/s41598-024-54119-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 02/08/2024] [Indexed: 02/16/2024] Open
Abstract
Analyses of registries and medical imaging suggest that laparoscopic surgery may be penalized with a high incidence of trocar-site hernias (TSH). In addition to trocar diameter, the location of the surgical wound (SW) may affect TSH incidence. The intra-abdominal pressure (IAP) exerted on the abdominal wall (AW) might also influence the appearance of TSH. In the present study, we used finite element (FE) simulations to predict the influence of trocar location and SW characteristics (stiffness) on the mechanical behavior of the AW subject to an IAP. Two models of laparoscopy patterns on the AW, with trocars in the 5-12 mm range, were generated. FE simulations for IAP values within the 4 kPa-20 kPa range were carried out using the Code Aster open-source software. Different stiffness levels of the SW tissue were considered. We found that midline-located surgical wounds barely deformed, even though they moved outwards along with the regular LA tissue. Laterally located SWs hardly changed their location but they experienced significant variations in their volume and shape. The amount of deformation of lateral SWs was found to strongly depend on their stiffness. Trocar incisions placed in a LA with non-diastatic dimensions do not compromise its mechanical integrity. The more lateral the trocars are placed, the greater is their deformation, regardless of their size. Thus, to prevent TSH it might be advisable to close lateral trocars with a suture, or even use a prosthetic reinforcement depending on the patient's risk factors (e.g., obesity).
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Affiliation(s)
- Lluís Tuset
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av. Països Catalans 26, Tarragona, Catalunya, Spain
| | - Manuel López-Cano
- Abdominal Wall Surgery Unit, Department of General Surgery, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Gerard Fortuny
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av. Països Catalans 26, Tarragona, Catalunya, Spain
| | - Josep M López
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av. Països Catalans 26, Tarragona, Catalunya, Spain
| | - Joan Herrero
- Departament d'Enginyeria Química, Universitat Rovira i Virgili, Av. Països Catalans 26, Tarragona, Catalunya, Spain
| | - Dolors Puigjaner
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av. Països Catalans 26, Tarragona, Catalunya, Spain.
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Vergari C, Persohn S, Rohan PY. The effect of breathing on the in vivo mechanical characterization of linea alba by ultrasound shearwave elastography. Comput Biol Med 2023; 167:107637. [PMID: 37897961 DOI: 10.1016/j.compbiomed.2023.107637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/09/2023] [Accepted: 10/24/2023] [Indexed: 10/30/2023]
Abstract
The most common surgical repair of abdominal wall hernia consists in implanting a mesh to reinforce hernia defects during the healing phase. Ultrasound shearwave elastography (SWE) is a promising non-invasive method to estimate soft tissue mechanical properties at bedside through shear wave speed (SWS) measurement. Combined with conventional ultrasonography, it could help the clinician plan surgery. In this work, a novel protocol is proposed to reliably assess the stiffness of the linea alba, and to evaluate the effect of breathing and of inflating the abdomen on SWS. Fifteen healthy adults were included. SWS was measured in the linea alba, in the longitudinal and transverse direction, during several breathing cycle and during active abdominal inflation. SWS during normal breathing was 2.3 [2.0; 2.5] m/s in longitudinal direction and 2.2 [1.9; 2.7] m/s in the transversal. Inflating the abdomen increased SWS both in longitudinal and transversal direction (3.5 [2.8; 5.8] m/s and 5.2 [3.0; 6.0] m/s, respectively). The novel protocol significantly improved the reproducibility relative to the literature (8% in the longitudinal direction and 14% in the transverse one). Breathing had a mild effect on SWS, and accounting for it only marginally improved the reproducibility. This study proved the feasibility of the method, and its potential clinical interest. Further studies on larger cohort should focus on improving our understanding of the relationship between abdominal wall properties and clinical outcomes, but also provide a cartography of the abdominal wall, beyond the linea alba.
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Affiliation(s)
- Claudio Vergari
- Arts et Métiers Institute of Technology, Institut de Biomécanique Humaine Georges Charpak, Université Sorbonne Paris Nord, Paris, France.
| | - Sylvain Persohn
- Arts et Métiers Institute of Technology, Institut de Biomécanique Humaine Georges Charpak, Université Sorbonne Paris Nord, Paris, France
| | - Pierre-Yves Rohan
- Arts et Métiers Institute of Technology, Institut de Biomécanique Humaine Georges Charpak, Université Sorbonne Paris Nord, Paris, France
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Whitehead-Clarke T, Brown C, Ail G, Mudera V, Smith C, Kureshi A. Characterisation of human posterior rectus sheath reveals mechanical and structural anisotropy. Clin Biomech (Bristol, Avon) 2023; 106:105989. [PMID: 37244136 DOI: 10.1016/j.clinbiomech.2023.105989] [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: 01/04/2023] [Revised: 05/01/2023] [Accepted: 05/10/2023] [Indexed: 05/29/2023]
Abstract
BACKGROUND Our work aims to investigate the mechanical properties of the human posterior rectus sheath in terms of its ultimate tensile stress, stiffness, thickness and anisotropy. It also aims to assess the collagen fibre organisation of the posterior rectus sheath using Second-Harmonic Generation microscopy. METHODS For mechanical analysis, twenty-five fresh-frozen samples of posterior rectus sheath were taken from six different cadaveric donors. They underwent uniaxial tensile stress testing until rupture either in the transverse (n = 15) or longitudinal (n = 10) plane. The thickness of each sample was also recorded using digital callipers. On a separate occasion, ten posterior rectus sheath samples and three anterior rectus sheath samples underwent microscopy and photography to assess collagen fibre organisation. FINDINGS samples had a mean ultimate tensile stress of 7.7 MPa (SD 4.9) in the transverse plane and 1.2 MPa (SD 0.8) in the longitudinal plane (P < 0.01). The same samples had a mean Youngs modulus of 11.1 MPa (SD 5.0) in the transverse plane and 1.7 MPa (SD 1.3) in the longitudinal plane (P < 0.01). The mean thickness of the posterior rectus sheath was 0.51 mm (SD 0.13). Transversely aligned collagen fibres could be identified within the posterior sheath tissue using Second-Harmonic Generation microscopy. INTERPRETATION The posterior rectus sheath displays mechanical and structural anisotropy with greater tensile stress and stiffness in the transverse plane compared to the longitudinal plane. The mean thickness of this layer is around 0.51 mm - consistent with other studies. The tissue is constructed of transversely aligned collagen fibres that are visible using Second-Harmonic Generation microscopy.
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Affiliation(s)
- Thomas Whitehead-Clarke
- Centre for 3D Models of Health and Disease, Division of Surgery and Interventional Science, University College London, UK.
| | | | - Geetika Ail
- Department of Anatomy, Brighton and Sussex Medical School, UK
| | - Vivek Mudera
- Division of Surgery and Interventional Science, University College London, UK
| | - Claire Smith
- Department of Anatomy, Brighton and Sussex Medical School, UK
| | - Alvena Kureshi
- Division of Surgery and Interventional Science, University College London, UK
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Nesbitt DQ, Burruel DE, Henderson BS, Lujan TJ. Finite element modeling of meniscal tears using continuum damage mechanics and digital image correlation. Sci Rep 2023; 13:4039. [PMID: 36899069 PMCID: PMC10006193 DOI: 10.1038/s41598-023-29111-z] [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: 07/25/2022] [Accepted: 01/31/2023] [Indexed: 03/12/2023] Open
Abstract
Meniscal tears are a common, painful, and debilitating knee injury with limited treatment options. Computational models that predict meniscal tears may help advance injury prevention and repair, but first these models must be validated using experimental data. Here we simulated meniscal tears with finite element analysis using continuum damage mechanics (CDM) in a transversely isotropic hyperelastic material. Finite element models were built to recreate the coupon geometry and loading conditions of forty uniaxial tensile experiments of human meniscus that were pulled to failure either parallel or perpendicular to the preferred fiber orientation. Two damage criteria were evaluated for all experiments: von Mises stress and maximum normal Lagrange strain. After we successfully fit all models to experimental force-displacement curves (grip-to-grip), we compared model predicted strains in the tear region at ultimate tensile strength to the strains measured experimentally with digital image correlation (DIC). In general, the damage models underpredicted the strains measured in the tear region, but models using von Mises stress damage criterion had better overall predictions and more accurately simulated experimental tear patterns. For the first time, this study has used DIC to expose strengths and weaknesses of using CDM to model failure behavior in soft fibrous tissue.
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Affiliation(s)
- Derek Q Nesbitt
- Biomedical Engineering Doctoral Program, Boise State University, Boise, ID, USA
| | - Dylan E Burruel
- Department of Mechanical and Biomedical Engineering, Boise State University, 1910 University Drive, Boise, ID, 83725-2085, USA
| | - Bradley S Henderson
- Department of Mechanical and Biomedical Engineering, Boise State University, 1910 University Drive, Boise, ID, 83725-2085, USA
| | - Trevor J Lujan
- Department of Mechanical and Biomedical Engineering, Boise State University, 1910 University Drive, Boise, ID, 83725-2085, USA.
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Pillet B, Badel P, Pierrat B. Effects of cryo-preservation on skeletal muscle tissues mechanical behavior under tensile and peeling tests until rupture. J Mech Behav Biomed Mater 2022; 132:105273. [PMID: 35617821 DOI: 10.1016/j.jmbbm.2022.105273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 04/21/2022] [Accepted: 05/13/2022] [Indexed: 11/18/2022]
Abstract
The most common method to study the mechanical behavior of soft tissue is to test animal specimens, which should be prepared as soon as possible after the death to avoid biological deterioration effects such as rigor mortis. Freezing and cryo-preservation could allow extending the time between procurement and implantation. From a mechanical perspective, tissue preservation could influence mechanical testing results. Therefore, this study focuses on the influence of cryo-preserved samples on their mechanical behavior, especially at the rupture. In order to analyze this aspect, two tests were performed on the porcine abdominal wall. A tensile test to study the elastic behavior of samples and the tensile strength until rupture. A peeling test to more finely investigate the cohesion between muscle fibers. No statistical difference could be observed following tensile test. However, peeling tests between cryo-preserved and control samples showed a clear statistical difference with a p-value of 0.0097 for Gp. Indeed, energy release rate was higher for the Cryo-preserve group than the Control group with Gp = 0.36 ± 0.07 N/mm vs 0.26 ± 0.10 N/mm. This difference suggests that the characterization of rupture energies for muscular tissue should be done without having frozen the samples, even with a cryopreservative agent. These results could also indicate that even if the rupture mode is the same between mechanical tests, a different rupture direction could imply different mechanical preservations for soft tissues. This study could help to understand the difficult mechanical preservation of soft tissues, especially on the rupture behavior. Future studies on skeletal muscles will be necessary to compare our results, especially in peeling.
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Affiliation(s)
- Baptiste Pillet
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, Etablissement Francais du Sang, INSERM, U 1059 Sainbiose, Centre CIS, F, 42023, Saint-Etienne, France.
| | - Pierre Badel
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, Etablissement Francais du Sang, INSERM, U 1059 Sainbiose, Centre CIS, F, 42023, Saint-Etienne, France
| | - Baptiste Pierrat
- Mines Saint-Etienne, Univ Lyon, Univ Jean Monnet, Etablissement Francais du Sang, INSERM, U 1059 Sainbiose, Centre CIS, F, 42023, Saint-Etienne, France
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8
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Jourdan A, Rapacchi S, Guye M, Bendahan D, Masson C, Bège T. Dynamic-MRI quantification of abdominal wall motion and deformation during breathing and muscular contraction. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2022; 217:106667. [PMID: 35231757 DOI: 10.1016/j.cmpb.2022.106667] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 01/15/2022] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND AND OBJECTIVE Biomechanical assessment of the abdominal wall represents a major prerequisite for a better understanding of physiological and pathological situations such as hernia, post-delivery recovery, muscle dystrophy or sarcopenia. Such an assessment is challenging and requires muscular deformations quantification which have been very scarcely reported in vivo. In the present study, we intended to characterize abdominal wall deformations in passive and active conditions using dynamic MRI combined to a semiautomatic segmentation procedure. METHODS Dynamic deformations resulting from three complementary exercises i.e. forced breathing, coughing and Valsalva maneuver were mapped in a transversal abdominal plane and so for twenty healthy volunteers. Real-time dynamic MRI series were acquired at a rate of 182 ms per image, then segmented semi-automatically to follow muscles deformation through each exercise. Circumferential and radial strains of each abdominal muscle were computed from the geometrical characteristics' quantification, namely the medial axis length and the thickness. Muscular radial displacement maps were computed using image registration. RESULTS Large variations in circumferential and radial strains were observed for the lateral muscles (LM) but remained low for the rectus abdominis muscles (RA). Contraction phases of each exercise led to LM muscle shortening down to -9.6 ± 5.9% during Valsalva maneuver with a 16.2 ± 9.6% thickness increase. Contraction also led to inward radial displacement of the LM up to 9.9 ± 4.1 mm during coughing. During maximal inhalation, a significant 10.0 ± 6.6% lengthening was quantified for LM while a significant thickness decrease was computed for the whole set of muscles (-14.7 ± 6.6% for LM and -7.3 ± 6.5% for RA). The largest displacement was observed for the medial part of RA (17.9 ± 8.0 mm) whereas the posterior part of LM underwent limited motion (2.8 ± 2.3 mm). Displacement rate and correlation between muscle thickness and medial axis length during each exercise provided insights regarding subject-specific muscle function. CONCLUSIONS Dynamic MRI is a promising tool for the assessment of the abdominal wall motion and deformations. The corresponding metrics which have been continuously recorded during the exercises provided global and regional quantitative information. These metrics offer perspectives for a genuine clinical evaluation tool dedicated to the assessment of abdominal muscles function in both healthy subjects and patients.
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Affiliation(s)
- Arthur Jourdan
- Aix-Marseille Univ, Univ Gustave Eiffel, IFSTTAR, LBA, F-13016 Marseille, France.
| | | | - Maxime Guye
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France; APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France.
| | | | - Catherine Masson
- Aix-Marseille Univ, Univ Gustave Eiffel, IFSTTAR, LBA, F-13016 Marseille, France.
| | - Thierry Bège
- Aix-Marseille Univ, Univ Gustave Eiffel, IFSTTAR, LBA, F-13016 Marseille, France; Department of General Surgery, Aix Marseille Univ, North Hospital, APHM, Marseille, France.
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Kirilova-Doneva M, Pashkouleva D. The effects of age and sex on the elastic mechanical properties of human abdominal fascia. Clin Biomech (Bristol, Avon) 2022; 92:105591. [PMID: 35131681 DOI: 10.1016/j.clinbiomech.2022.105591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 12/19/2021] [Accepted: 01/28/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND The abdominal hernias become more prevalent with age, that can adversely affect life quality. The mechanical properties of abdominal wall layers are supposed to play a significant role in developing of an abdominal hernia.The objective of this study was to determine the mechanical properties of the human abdominal layer - fascia and the effects of age and sex on it for choosing the proper brand of hernia mesh. METHODS 78 samples harvested from 19 fresh cadavers were subjected to uniaxial tension tests and divided into four groups according to age. Group A corresponds to age up to 60 years, Group B to age 61-70 years, Group C to age 71-80 years and Group D to 81-90 years. Median stress-stretch ratio curves with respect to age, sex and direction of loading were obtained. Median values of the maximum tensile stress, stretch at maximum stress and elastic modulus calculated at 5% strain were determined. FINDINGS The abdominal fascia showed large variations between specimens depending on age and sex. The stiffness of the fascia increased with age. There is statistically significant differences between the median curves of male samples (P = 0.008) and female samples (P = 0.019) according to age in the L direction. Statistically significant differences between the values of maximum stress (P = 0.01) and elastic modulus (P = 0.003) from Group C in the L direction and maximum stress (P = 0.03) from Group D in the T direction was established. INTERPRETATION The female samples are stiffer than male samples especially after 80 years.
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Affiliation(s)
- Miglena Kirilova-Doneva
- Faculty of Pharmacy, Medical University-Sofia, Sofia, Bulgaria; Institute of Mechanics, Bulgarian Academy of Sciences, Sofia, Bulgaria.
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A Review on Damage and Rupture Modelling for Soft Tissues. Bioengineering (Basel) 2022; 9:bioengineering9010026. [PMID: 35049735 PMCID: PMC8773318 DOI: 10.3390/bioengineering9010026] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 01/04/2022] [Accepted: 01/05/2022] [Indexed: 11/16/2022] Open
Abstract
Computational modelling of damage and rupture of non-connective and connective soft tissues due to pathological and supra-physiological mechanisms is vital in the fundamental understanding of failures. Recent advancements in soft tissue damage models play an essential role in developing artificial tissues, medical devices/implants, and surgical intervention practices. The current article reviews the recently developed damage models and rupture models that considered the microstructure of the tissues. Earlier review works presented damage and rupture separately, wherein this work reviews both damage and rupture in soft tissues. Wherein the present article provides a detailed review of various models on the damage evolution and tear in soft tissues focusing on key conceptual ideas, advantages, limitations, and challenges. Some key challenges of damage and rupture models are outlined in the article, which helps extend the present damage and rupture models to various soft tissues.
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11
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Mazzinari G, Diaz-Cambronero O, Serpa Neto A, Martínez AC, Rovira L, Argente Navarro MP, Malbrain MLNG, Pelosi P, Gama de Abreu M, Hollmann MW, Schultz MJ. Modeling intra-abdominal volume and respiratory driving pressure during pneumoperitoneum insufflation-a patient-level data meta-analysis. J Appl Physiol (1985) 2020; 130:721-728. [PMID: 33357006 DOI: 10.1152/japplphysiol.00814.2020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
During pneumoperitoneum, intra-abdominal pressure (IAP) is usually kept at 12-14 mmHg. There is no clinical benefit in IAP increments if they do not increase intra-abdominal volume IAV. We aimed to estimate IAV (ΔIAV) and respiratory driving pressure changes (ΔPRS) in relation to changes in IAP (ΔIAP). We carried out a patient-level meta-analysis of 204 adult patients with available data on IAV and ΔPRS during pneumoperitoneum from three trials assessing the effect of IAP on postoperative recovery and airway pressure during laparoscopic surgery under general anesthesia. The primary endpoint was ΔIAV, and the secondary endpoint was ΔPRS. The endpoints' response to ΔIAP was modeled using mixed multivariable Bayesian regression to estimate which mathematical function best fitted it. IAP values on the pressure-volume (PV) curve where the endpoint rate of change according to IAP decreased were identified. Abdomino-thoracic transmission (ATT) rate, that is, the rate ΔPRS change to ΔIAP was also estimated. The best-fitting function was sigmoid logistic and linear for IAV and ΔPRS response, respectively. Increments in IAV reached a plateau at 6.0 [95%CI 5.9-6.2] L. ΔIAV for each ΔIAP decreased at IAP ranging from 9.8 [95%CI 9.7-9.9] to 12.2 [12.0-12.3] mmHg. ATT rate was 0.65 [95%CI 0.62-0.68]. One mmHg of IAP raised ΔPRS 0.88 cmH2O. During pneumoperitoneum, IAP has a nonlinear relationship with IAV and a linear one with ΔPRS. IAP should be set below the point where IAV gains diminish.NEW & NOTEWORTHY We found that intra-abdominal volume changes related to intra-abdominal pressure increase reached a plateau with diminishing gains in commonly used pneumoperitoneum pressure ranges. We also found a linear relationship between intra-abdominal pressure and respiratory driving pressure, a known marker of postoperative pulmonary complications.
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Affiliation(s)
- Guido Mazzinari
- Research Group in Perioperative Medicine, Hospital Universitario y Politécnico la Fe, Valencia, Spain.,Department of Anaesthesiology, Hospital Universitario y Politécnico la Fe, Valencia, Spain
| | - Oscar Diaz-Cambronero
- Research Group in Perioperative Medicine, Hospital Universitario y Politécnico la Fe, Valencia, Spain.,Department of Anaesthesiology, Hospital Universitario y Politécnico la Fe, Valencia, Spain.,Spanish Clinical Research Network (SCReN), SCReN-IIS La Fe, Madrid, Spain
| | - Ary Serpa Neto
- Department of Intensive Care & Laboratory of Experimental Intensive Care and Anesthesiology (LEICA), Amsterdam University Medical Center, location "AMC." Amsterdam, The Netherlands.,Department of Critical Care Medicine, Hospital Israelita Albert Einstein, São Paulo, Brazil.,Pulmonary Division, Cardio-Pulmonary Department, Instituto do Coração, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Antonio Cañada Martínez
- Data Science, Biostatistics and Bioinformatics Unit, Instituto de Investigacion Sanitaria la Fe, Valencia, Spain
| | - Lucas Rovira
- Department of Anaesthesiology, Consorcio Hospital General Universitario, Valencia, Spain
| | - María Pilar Argente Navarro
- Research Group in Perioperative Medicine, Hospital Universitario y Politécnico la Fe, Valencia, Spain.,Department of Anaesthesiology, Hospital Universitario y Politécnico la Fe, Valencia, Spain
| | - Manu L N G Malbrain
- Department of Intensive Care Medicine, University Hospital Brussels (UZB), Brussels, Belgium.,Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,International Fluid Academy, Lovenjoel, Belgium
| | - Paolo Pelosi
- San Martino Policlinico Hospital-IRCCS for Oncology and Neurosciences, Genoa, Italy.,Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
| | - Marcelo Gama de Abreu
- Department of Anesthesiology and Intensive Care Therapy, Pulmonary Engineering Group, Technische Universität Dresden, Dresden, Germany.,Outcomes Research Consortium, Cleveland, Ohio
| | - Markus W Hollmann
- Department of Intensive Care & Laboratory of Experimental Intensive Care and Anesthesiology (LEICA), Amsterdam University Medical Center, location "AMC." Amsterdam, The Netherlands.,Department of Anaesthesiology, Amsterdam University Medical Center, location "AMC," Amsterdam, The Netherlands
| | - Marcus J Schultz
- Department of Intensive Care & Laboratory of Experimental Intensive Care and Anesthesiology (LEICA), Amsterdam University Medical Center, location "AMC." Amsterdam, The Netherlands.,Mahidol Oxford Tropical Medicine Research Unit (MORU), Mahidol University, Bangkok, Thailand.,Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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12
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Kirilova-Doneva M, Pashkouleva D, Stoytchev S. Age-related changes in mechanical properties of human abdominal fascia. Med Biol Eng Comput 2020; 58:1565-1573. [PMID: 32415553 DOI: 10.1007/s11517-020-02172-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/26/2020] [Indexed: 11/29/2022]
Abstract
The purpose of this study is to assess and model age-related changes in the mechanical properties of human fascia. The samples were divided into three age groups: group A-up to 60 years (mean age 52.5 ± 6 years), group B-61-80 years (mean age 70.4 ± 5.2 years), and group C-81-90 years (mean age 83.2 ± 2 years). A uniaxial tensile test was applied to fascia specimens cut perpendicular and parallel to fibers. The secant modulus at 5% strain, the maximum stress, and the stretch at maximum stress were calculated from the stress-stretch ratio curves. The results indicated an increase in the secant modulus with the increased age. The trend is clearer in the longitudinal direction. Considering the strain energy function which accounts the isotropic and non-isotropic response of the fascia where isotropic and anisotropic parts are split, we evaluated which material model is the most suitable to present isotropic mechanical behavior of the tissue. The experimental stress-stretch ratio curves were approximated using Mooney-Rivlin, Yeoh, and neo-Hookean strain energy functions and a good match between theoretical and experimental results was obtained. On the basis of objective function values and normalized mean square root error, we recommend using the Yeoh model to describe the isotropic mechanical behavior of human abdominal fascia. Graphical abstract .
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Affiliation(s)
- Miglena Kirilova-Doneva
- Faculty of Pharmacy, Medical University of Sofia, 2 Dunav Str., 1000, Sofia, Bulgaria. .,Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 4, Sofia, Bulgaria.
| | - Dessislava Pashkouleva
- Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 4, Sofia, Bulgaria
| | - Stoyan Stoytchev
- Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 4, Sofia, Bulgaria
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13
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Tuset L, Fortuny G, Herrero J, Puigjaner D, López JM. Implementation of a new constitutive model for abdominal muscles. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2019; 179:104988. [PMID: 31443865 DOI: 10.1016/j.cmpb.2019.104988] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/02/2019] [Accepted: 07/15/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE Abdominal hernia repair is one of the most often performed surgical procedures worldwide. Numerical simulations of the abdominal wall mechanics can be a valuable tool to devise actions aimed at preventing hernia formation. A first step towards this goal is the development of consistent constitutive models for the tissues that form the human abdominal wall. In this study we propose, for each of the tissues involved, a new formulation of the so-called transversely isotropic hyperelastic model (TIHM). METHODS We propose a new TIHM for the human abdominal wall tissues and we present a systemic view of the methodology that we have implemented in the present study. First we consider the mathematical background of the TIHM. The novelty of our formulation is that both the isotropic and the fiber contributions to the strain energy function are characterized exclusively by polynomial convex functions of certain invariant quantities. Then, we provide a detailed description on how the constitutive model is implemented into an open source finite element (FE) software. In our approach we use the specific interface provided by the MFront software to incorporate our TIHM formulation into the Code Aster FE solver. For each of the tissues considered, the values of the TIHM constants are adjusted by means of a numerical simulation of previous experimental data from tensile tests. RESULTS We studied the following abdominal wall tissues: linea alba, rectus sheath, external oblique muscle, internal oblique muscle, transversus abdominis muscle and rectus abdominis muscle. Our formulation closely reproduces tensile test data for each tissue in the corresponding FE numerical simulation. CONCLUSIONS The new TIHM formulation is suitable for a future numerical investigation of the abdominal wall, which will in turn help us to assess the best zone to practice a colostomy. The methodology implemented in the present study can be easily extended in the future to develop and implement a TIHM for active muscles and/or a different type of constitutive model which might be suitable to characterize other tissues of biomedical interest.
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Affiliation(s)
- Lluís Tuset
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av Països Catalans 26, Tarragona, Catalunya, Spain.
| | - Gerard Fortuny
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av Països Catalans 26, Tarragona, Catalunya, Spain.
| | - Joan Herrero
- Departament d'Enginyeria Química, Universitat Rovira i Virgili, Av Països Catalans 26, Tarragona, Catalunya, Spain.
| | - Dolors Puigjaner
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av Països Catalans 26, Tarragona, Catalunya, Spain.
| | - Josep M López
- Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, Av Països Catalans 26, Tarragona, Catalunya, Spain.
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14
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Todros S, de Cesare N, Pianigiani S, Concheri G, Savio G, Natali AN, Pavan PG. 3D surface imaging of abdominal wall muscular contraction. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2019; 175:103-109. [PMID: 31104699 DOI: 10.1016/j.cmpb.2019.04.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 04/10/2019] [Accepted: 04/11/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND AND OBJECTIVE The biomechanical analysis of the abdominal wall should take into account muscle activation and related phenomena, such as intra-abdominal pressure variation and abdomen surface deformation. The geometry of abdominal surface and its deformation during contraction have not been extensively characterized, while represent a key issue to be investigated. METHODS In this work, the antero-lateral abdominal wall surface of ten healthy volunteers in supine position is acquired via laser scanning in relaxed conditions and during abdominal muscles contraction, repeating each acquisition six times. The average relaxed and contracted abdominal surfaces are compared for each subject and displacements measured. RESULTS Muscular activation induces raising in the region adjacent to linea alba along the posterior-anterior direction and a simultaneous lowering along lateral-medial direction of the abdominal wall sides. Displacements reach a maximum value of 12.5 mm for the involved subjects. The coefficient of variation associated to the abdomen surface measurements in the same configuration (relaxed or contracted) is below 0.75%. Non-parametric Mann-Whitney U test highlights that the differences between relaxed and contracted abdominal wall surfaces are significant (p < 0.01). CONCLUSIONS Laser scanning is an accurate and reliable method to evaluate surface changes on the abdominal wall during muscular contraction. The results of this experimental activity can be useful to validate numerical models aimed at describing abdominal wall biomechanics.
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Affiliation(s)
- Silvia Todros
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
| | - Niccolò de Cesare
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy.
| | - Silvia Pianigiani
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
| | - Gianmaria Concheri
- Department of Civil, Environmental and Architectural Engineering, Laboratory of Design Tools and Methods in Industrial Engineering, University of Padova, Padova, Italy
| | - Gianpaolo Savio
- Department of Civil, Environmental and Architectural Engineering, Laboratory of Design Tools and Methods in Industrial Engineering, University of Padova, Padova, Italy
| | - Arturo N Natali
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
| | - Piero G Pavan
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
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15
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Pavan PG, Todros S, Pachera P, Pianigiani S, Natali AN. The effects of the muscular contraction on the abdominal biomechanics: a numerical investigation. Comput Methods Biomech Biomed Engin 2019; 22:139-148. [DOI: 10.1080/10255842.2018.1540695] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Piero G. Pavan
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, via Venezia 1, I–35131 Padova, Italy
| | - Silvia Todros
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, via Venezia 1, I–35131 Padova, Italy
| | - Paola Pachera
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, via Venezia 1, I–35131 Padova, Italy
| | - Silvia Pianigiani
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, via Venezia 1, I–35131 Padova, Italy
| | - Arturo N. Natali
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, via Venezia 1, I–35131 Padova, Italy
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16
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Astruc L, De Meulaere M, Witz JF, Nováček V, Turquier F, Hoc T, Brieu M. Characterization of the anisotropic mechanical behavior of human abdominal wall connective tissues. J Mech Behav Biomed Mater 2018; 82:45-50. [PMID: 29567529 DOI: 10.1016/j.jmbbm.2018.03.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 03/05/2018] [Accepted: 03/09/2018] [Indexed: 11/30/2022]
Abstract
Abdominal wall sheathing tissues are commonly involved in hernia formation. However, there is very limited work studying mechanics of all tissues from the same donor which prevents a complete understanding of the abdominal wall behavior and the differences in these tissues. The aim of this study was to investigate the differences between the mechanical properties of the linea alba and the anterior and posterior rectus sheaths from a macroscopic point of view. Eight full-thickness human anterior abdominal walls of both genders were collected and longitudinal and transverse samples were harvested from the three sheathing connective tissues. The total of 398 uniaxial tensile tests was conducted and the mechanical characteristics of the behavior (tangent rigidities for small and large deformations) were determined. Statistical comparisons highlighted heterogeneity and non-linearity in behavior of the three tissues under both small and large deformations. High anisotropy was observed under small and large deformations with higher stress in the transverse direction. Variabilities in the mechanical properties of the linea alba according to the gender and location were also identified. Finally, data dispersion correlated with microstructure revealed that macroscopic characterization is not sufficient to fully describe behavior. Microstructure consideration is needed. These results provide a better understanding of the mechanical behavior of the abdominal wall sheathing tissues as well as the directions for microstructure-based constitutive model.
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Affiliation(s)
- Laure Astruc
- Univ. Lille, CNRS, Centrale Lille, FRE 2016 - LaMcube - Laboratoire de mécanique multiphysique multiéchelle, F-59000 Lille, France.
| | - Maurice De Meulaere
- Laboratoire d'Anatomie, CHRU de Lille, 1 Place de Verdun, 59045 Lille, France
| | - Jean-François Witz
- Univ. Lille, CNRS, Centrale Lille, FRE 2016 - LaMcube - Laboratoire de mécanique multiphysique multiéchelle, F-59000 Lille, France
| | - Vit Nováček
- Medtronic, Sofradim Production, 116 avenue du Formans, 01600 Trévoux, France
| | - Frédéric Turquier
- Medtronic, Sofradim Production, 116 avenue du Formans, 01600 Trévoux, France
| | - Thierry Hoc
- LTDS, UMR CNRS 5513, Université de Lyon, École Centrale de Lyon, 36 av Guy de Collongue, 69134 Écully Cedex, France
| | - Mathias Brieu
- Univ. Lille, CNRS, Centrale Lille, FRE 2016 - LaMcube - Laboratoire de mécanique multiphysique multiéchelle, F-59000 Lille, France
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17
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Ramo N, Shetye SS, Puttlitz CM. Damage Accumulation Modeling and Rate Dependency of Spinal Dura Mater. ACTA ACUST UNITED AC 2017; 1:0110061-110068. [DOI: 10.1115/1.4038261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/17/2017] [Indexed: 11/08/2022]
Abstract
As the strongest of the meningeal tissues, the spinal dura mater plays an important role in the overall behavior of the spinal cord-meningeal complex (SCM). It follows that the accumulation of damage affects the dura mater's ability to protect the cord from excessive mechanical loads. Unfortunately, current computational investigations of spinal cord injury (SCI) etiology typically do not include postyield behavior. Therefore, a more detailed description of the material behavior of the spinal dura mater, including characterization of damage accumulation, is required to comprehensively study SCI. Continuum mechanics-based viscoelastic damage theories have been previously applied to other biological tissues; however, the current work is the first to report damage accumulation modeling in a tissue of the SCM complex. Longitudinal (i.e., cranial-to-caudal long-axis) samples of ovine cervical dura mater were tensioned-to-failure at one of three strain rates (quasi-static, 0.05/s, and 0.3/s). The resulting stress–strain data were fit to a hyperelastic continuum damage model to characterize the strain-rate-dependent subfailure and failure behavior. The results show that the damage behavior of the fibrous and matrix components of the dura mater are strain-rate dependent, with distinct behaviors when exposed to strain rates above that experienced during normal voluntary neck motion suggesting the possible existence of a protective mechanism.
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Affiliation(s)
- Nicole Ramo
- School of Biomedical Engineering, Colorado State University, 1376 Campus Delivery, Fort Collins, CO 80523-1376
| | - Snehal S. Shetye
- Department of Mechanical Engineering, Colorado State University, 1374 Campus Delivery, Fort Collins, CO 80523-1374
| | - Christian M. Puttlitz
- School of Biomedical Engineering, Department of Mechanical Engineering, Department of Clinical Sciences, Colorado State University, 1374 Campus Delivery, Fort Collins, CO 80523-1374
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18
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Deeken CR, Lake SP. Mechanical properties of the abdominal wall and biomaterials utilized for hernia repair. J Mech Behav Biomed Mater 2017; 74:411-427. [DOI: 10.1016/j.jmbbm.2017.05.008] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/26/2017] [Accepted: 05/04/2017] [Indexed: 12/29/2022]
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19
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Kahan LG, Lake SP, McAllister JM, Tan WH, Yu J, Thompson D, Brunt LM, Blatnik JA. Combined in vivo and ex vivo analysis of mesh mechanics in a porcine hernia model. Surg Endosc 2017; 32:820-830. [DOI: 10.1007/s00464-017-5749-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/14/2017] [Indexed: 12/29/2022]
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20
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Towards the mechanical characterization of abdominal wall by inverse analysis. J Mech Behav Biomed Mater 2017; 66:127-137. [DOI: 10.1016/j.jmbbm.2016.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/24/2016] [Accepted: 11/01/2016] [Indexed: 12/31/2022]
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21
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Comellas E, Gasser TC, Bellomo FJ, Oller S. A homeostatic-driven turnover remodelling constitutive model for healing in soft tissues. J R Soc Interface 2016; 13:rsif.2015.1081. [PMID: 27009177 DOI: 10.1098/rsif.2015.1081] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 03/01/2016] [Indexed: 01/08/2023] Open
Abstract
Remodelling of soft biological tissue is characterized by interacting biochemical and biomechanical events, which change the tissue's microstructure, and, consequently, its macroscopic mechanical properties. Remodelling is a well-defined stage of the healing process, and aims at recovering or repairing the injured extracellular matrix. Like other physiological processes, remodelling is thought to be driven by homeostasis, i.e. it tends to re-establish the properties of the uninjured tissue. However, homeostasis may never be reached, such that remodelling may also appear as a continuous pathological transformation of diseased tissues during aneurysm expansion, for example. A simple constitutive model for soft biological tissues that regards remodelling as homeostatic-driven turnover is developed. Specifically, the recoverable effective tissue damage, whose rate is the sum of a mechanical damage rate and a healing rate, serves as a scalar internal thermodynamic variable. In order to integrate the biochemical and biomechanical aspects of remodelling, the healing rate is, on the one hand, driven by mechanical stimuli, but, on the other hand, subjected to simple metabolic constraints. The proposed model is formulated in accordance with continuum damage mechanics within an open-system thermodynamics framework. The numerical implementation in an in-house finite-element code is described, particularized for Ogden hyperelasticity. Numerical examples illustrate the basic constitutive characteristics of the model and demonstrate its potential in representing aspects of remodelling of soft tissues. Simulation results are verified for their plausibility, but also validated against reported experimental data.
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Affiliation(s)
- Ester Comellas
- International Center for Numerical Methods in Engineering (CIMNE), Campus Nord UPC, Building C1, c/Gran Capita s/n, 08034 Barcelona, Spain Department of Strength of Materials and Structural Engineering, ETSECCPB, Universitat Politcnica de Catalunya, Barcelona Tech (UPC), Campus Nord, Building C1, c/Jordi Girona 1-3, 08034 Barcelona, Spain
| | - T Christian Gasser
- Department of Solid Mechanics, School of Engineering Sciences, KTH Royal Institute of Technology, Teknikringen 8, 100 44 Stockholm, Sweden
| | - Facundo J Bellomo
- INIQUI (CONICET), Faculty of Engineering, National University of Salta, Av. Bolivia 5150, 4400 Salta, Argentina
| | - Sergio Oller
- International Center for Numerical Methods in Engineering (CIMNE), Campus Nord UPC, Building C1, c/Gran Capita s/n, 08034 Barcelona, Spain Department of Strength of Materials and Structural Engineering, ETSECCPB, Universitat Politcnica de Catalunya, Barcelona Tech (UPC), Campus Nord, Building C1, c/Jordi Girona 1-3, 08034 Barcelona, Spain
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22
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Li W, Luo X. An Invariant-Based Damage Model for Human and Animal Skins. Ann Biomed Eng 2016; 44:3109-3122. [PMID: 27066788 PMCID: PMC5042997 DOI: 10.1007/s10439-016-1603-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/31/2016] [Indexed: 11/29/2022]
Abstract
Constitutive modelling of skins that account for damage effects is important to provide insight for various clinical applications, such as skin trauma and injury, artificial skin design, skin aging, disease diagnosis, surgery, as well as comparative studies of skin biomechanics between species. In this study, a new damage model for human and animal skins is proposed for the first time. The model is nonlinear, anisotropic, invariant-based, and is based on the Gasser-Ogden-Holzapfel constitutive law initially developed for arteries. Taking account of the mean collagen fibre orientation and its dispersion, the new model can describe a wide range of skins with damage. The model is first tested on the uniaxial test data of human skin and then applied to nine groups of uniaxial test data for the human, swine, rabbit, bovine and rhino skins. The material parameters can be inversely estimated based on uniaxial tests using the optimization method in MATLAB with a root mean square error ranged between 2.15% and 12.18%. A sensitivity study confirms that the fibre orientation dispersion and the mean fibre angle are among the most important factors that influence the behaviour of the damage model. In addition, these two parameters can only be reliably estimated if some histological information is provided. We also found that depending on the location of skins, the tissue damage may be brittle controlled by the fibre breaking limit (i.e., when the fibre stretch is greater than 1.13-1.32, depending on the species), or ductile (due to both the fibre and the matrix damages). The brittle damages seem to occur mostly in the back, and the ductile damages are seen from samples taken from the belly. The proposed constitutive model may be applied to various clinical applications that require knowledge of the mechanical response of human and animal skins.
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Affiliation(s)
- Wenguang Li
- School of Engineering, University of Glasgow, Glasgow, G12 8QQ, UK.
| | - Xiaoyu Luo
- School of Mathematics and Statistics, University of Glasgow, Glasgow, G12 8QW, UK
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23
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Prostheses size dependency of the mechanical response of the herniated human abdomen. Hernia 2016; 20:839-848. [DOI: 10.1007/s10029-016-1525-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 07/29/2016] [Indexed: 10/21/2022]
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24
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Tran D, Podwojewski F, Beillas P, Ottenio M, Voirin D, Turquier F, Mitton D. Abdominal wall muscle elasticity and abdomen local stiffness on healthy volunteers during various physiological activities. J Mech Behav Biomed Mater 2016; 60:451-459. [DOI: 10.1016/j.jmbbm.2016.03.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 02/19/2016] [Accepted: 03/03/2016] [Indexed: 10/22/2022]
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25
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Abstract
Damage to soft tissues in the human body has been investigated for applications in healthcare, sports, and biomedical engineering. This paper reviews and classifies damage models for soft tissues to summarize achievements, identify new directions, and facilitate finite element analysis. The main ideas of damage modeling methods are illustrated and interpreted. A few key issues related to damage models, such as experimental data curve-fitting, computational effort, connection between damage and fractures/cracks, damage model applications, and fracture/crack extension simulation, are discussed. Several new challenges in the field are identified and outlined. This review can be useful for developing more advanced damage models and extending damage modeling methods to a variety of soft tissues.
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Affiliation(s)
- Wenguang Li
- School of Engineering, University of Glasgow, Glasgow, G12 8QQ UK
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26
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A numerical investigation of the healthy abdominal wall structures. J Biomech 2016; 49:1818-1823. [PMID: 27133659 DOI: 10.1016/j.jbiomech.2016.04.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 04/15/2016] [Accepted: 04/18/2016] [Indexed: 10/21/2022]
Abstract
The present work aims to assess, via numerical modeling, the global passive mechanical behavior of the healthy abdominal wall under the action of pressures that characterize different daily tasks and physiological functions. The evaluation of a normal range of intra-abdominal pressure (IAP) during activities of daily living is fundamental because pressure alterations can cause several adverse effects. At this purpose, a finite element model is developed from literature histomorphometric data and from diagnostic images of Computed Tomography (CT), detailing the different anatomical regions. Numerical simulations cover an IAP up to the physiological limit of 171 (0.0223MPa) mmHg reached while jumping. Numerical results are in agreement with evidences on physiological abdomens when evaluating the local deformations along the craniocaudal direction, the transversal load forces in different regions and the increase of the abdominal area at a IAP of 12mmHg. The developed model can be upgraded for the investigation of the abdominal hernia repair and the assessment of prostheses mechanical compatibility, correlating stiffness and tensile strength of the abdominal tissues with those of surgical meshes.
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27
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Todros S, Pavan PG, Pachera P, Natali AN. Synthetic surgical meshes used in abdominal wall surgery: Part II-Biomechanical aspects. J Biomed Mater Res B Appl Biomater 2015; 105:892-903. [PMID: 26687728 DOI: 10.1002/jbm.b.33584] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 10/26/2015] [Accepted: 11/18/2015] [Indexed: 01/29/2023]
Abstract
This work reports the second part of a review on synthetic surgical meshes used for abdominal hernia repair. While material and structural characteristics, together with mesh-tissue interaction, were considered in a previous article (Part I), biomechanical behavior is described here in more detail. The role of the prosthesis is to strengthen the impaired abdominal wall, mimicking autologous tissue without reducing its compliance. Consequently, mesh mechanical properties play a crucial role in a successful surgical repair. The main available techniques for mechanical testing, such as uniaxial and biaxial tensile testing, ball burst, suture retention strength, and tear resistance testing, are described in depth. Among these methods, the biaxial tensile test is the one that can more faithfully reproduce the physiological loading condition. An outline of the most significant results documented in the literature is reported, showing the variety of data on mesh mechanical properties. Synthetic surgical meshes generally follow a non-linear stress-strain behavior, with mechanical characteristics dependant on test direction due to mesh anisotropy. Ex-vivo tests revealed an increased stiffness in mesh explants due to the gradual ingrowth of the host tissue after implant. In general, the absence of standardization in test methods and terminology makes it difficult to compare results from different studies. Numerical models of the abdominal wall interacting with surgical meshes were also discussed representing a potential tool for the selection of suitable prostheses. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 892-903, 2017.
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Affiliation(s)
- S Todros
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
| | - P G Pavan
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
| | - P Pachera
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
| | - A N Natali
- Department of Industrial Engineering, Centre for Mechanics of Biological Materials, University of Padova, Padova, Italy
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Simón-Allué R, Montiel J, Bellón J, Calvo B. Developing a new methodology to characterize in vivo the passive mechanical behavior of abdominal wall on an animal model. J Mech Behav Biomed Mater 2015. [DOI: 10.1016/j.jmbbm.2015.06.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Acosta Santamaría V, Siret O, Badel P, Guerin G, Novacek V, Turquier F, Avril S. Material model calibration from planar tension tests on porcine linea alba. J Mech Behav Biomed Mater 2015; 43:26-34. [DOI: 10.1016/j.jmbbm.2014.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 11/30/2014] [Accepted: 12/04/2014] [Indexed: 11/24/2022]
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Podwojewski F, Otténio M, Beillas P, Guérin G, Turquier F, Mitton D. Mechanical response of human abdominal walls ex vivo: Effect of an incisional hernia and a mesh repair. J Mech Behav Biomed Mater 2014; 38:126-33. [DOI: 10.1016/j.jmbbm.2014.07.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 06/26/2014] [Accepted: 07/01/2014] [Indexed: 11/15/2022]
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García A, Martínez MA, Peña E. Determination and modeling of the inelasticity over the length of the porcine carotid artery. J Biomech Eng 2014; 135:31004. [PMID: 24231815 DOI: 10.1115/1.4023371] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 01/10/2013] [Indexed: 11/08/2022]
Abstract
The study of the mechanical properties of swine carotids has clinical relevance because it is important for the appropriate design of intravascular devices in the animal trial phases. The inelastic properties of porcine carotid tissue were investigated. Experimental uniaxial cyclic tests were performed along the longitudinal and circumferential directions of vessels. The work focused on the determination, comparison, and constitutive modeling of the softening properties and residual stretch set of the swine carotid artery over long stretches and stress levels in both proximal and distal regions. It was observed that the residual strain depends on the maximum stretch in the previous load cycle. The strain was higher for distal than for proximal samples and for circumferential than for longitudinal samples. In addition, a pseudoelastic model was used to reproduce the residual stretch and softening behavior of the carotid artery. The model presented a good approximation of the experimental data. The results demonstrate that the final results in animal trial studies could be affected by the location studied along the length of the porcine carotid.
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Deeken CR, Thompson DM, Castile RM, Lake SP. Biaxial analysis of synthetic scaffolds for hernia repair demonstrates variability in mechanical anisotropy, non-linearity and hysteresis. J Mech Behav Biomed Mater 2014; 38:6-16. [PMID: 24997427 DOI: 10.1016/j.jmbbm.2014.06.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 05/28/2014] [Accepted: 06/05/2014] [Indexed: 01/05/2023]
Abstract
BACKGROUND Over the past 60 years, the soft tissue repair market has grown to include over 50 types of hernia repair materials. Surgeons typically implant these materials in the orientation that provides maximum overlap of the mesh over the defect, with little regard for mechanical properties of the mesh material. If the characteristics of the meshes were better understood, an appropriate material could be identified for each patient, and meshes could be placed to optimize integration with neighboring tissue and avoid the mechanical mis-match that can lead to impaired graft fixation. The purpose of this study was to fully characterize and compare the mechanical properties of thirteen types of hernia repair materials via planar biaxial tensile testing. METHODS Equibiaxial (i.e., equal simultaneous loading in both directions) and strip biaxial (i.e., loading in one direction with the other direction held fixed) tests were utilized as physiologically relevant loading regimes. After applying a 0.1N pre-load on each arm, samples were subjected to equibiaxial cyclic loading using a triangular waveform to 2.5mm displacement on each arm at 0.1Hz for 10 cycles. Samples were then subjected to two strip biaxial tests (using the same cyclic loading protocol), where extension was applied along a single axis with the other axis held fixed. RESULTS The thirteen evaluated mesh types exhibited a wide range of mechanical properties. Some were nearly isotropic (C-QUR™, DUALMESH(®), PHYSIOMESH™, and PROCEED(®)), while others were highly anisotropic (Ventralight™ ST, Bard™ Mesh, and Bard™ Soft Mesh). Some displayed nearly linear behavior (Bard™ Mesh), while others were non-linear with a long toe region followed by a sharp rise in tension (INFINIT(®)). These materials are currently utilized in clinical settings as if they are uniform and interchangeable, and clearly this is not the case. The mechanical properties most advantageous for successful hernia repairs are currently only vaguely described in the clinical literature. The characteristics of the human abdominal wall must be extensively characterized to provide a thorough understanding of the tissue being reinforced/replaced by these meshes. A better understanding of these mechanical differences would enable matching of patient characteristics to a specific mesh with the properties best suited to that particular repair.
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Affiliation(s)
- Corey R Deeken
- Department of Surgery, Section of Minimally Invasive Surgery, Washington University in St. Louis, St. Louis, MO, USA
| | - Dominic M Thompson
- Department of Surgery, Section of Minimally Invasive Surgery, Washington University in St. Louis, St. Louis, MO, USA
| | - Ryan M Castile
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Spencer P Lake
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, St. Louis, MO, USA.
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Lyons M, Winter DC, Simms CK. Mechanical characterisation of porcine rectus sheath under uniaxial and biaxial tension. J Biomech 2014; 47:1876-84. [DOI: 10.1016/j.jbiomech.2014.03.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 02/12/2014] [Accepted: 03/01/2014] [Indexed: 12/11/2022]
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Trajkovski A, Omerović S, Hribernik M, Prebil I. Failure Properties and Damage of Cervical Spine Ligaments, Experiments and Modeling. J Biomech Eng 2014; 136:031002. [DOI: 10.1115/1.4026424] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 01/06/2014] [Indexed: 11/08/2022]
Abstract
Cervical spine ligaments have an important role in providing spinal cord stability and restricting excessive movements. Therefore, it is of great importance to study the mechanical properties and model the response of these ligaments. The aim of this study is to characterize the aging effects on the failure properties and model the damage of three cervical spine ligaments: the anterior and the posterior longitudinal ligament and the ligamentum flavum. A total of 46 samples of human cadaveric ligaments removed within 24–48 h after death have been tested. Uniaxial tension tests along the fiber direction were performed in physiological conditions. The results showed that aging decreased the failure properties of all three ligaments (failure load, failure elongation). Furthermore, the reported nonlinear response of cervical ligaments has been modeled with a combination of the previously reported hyperelastic and damage model. The model predicted a nonlinear response and damage region. The model fittings are in agreement with the experimental data and the quality of agreement is represented with the values of the coefficient of determination close to 1.
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Affiliation(s)
- Ana Trajkovski
- Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva cesta 6, Ljubljana 1000, Slovenia e-mail:
| | - Senad Omerović
- Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva cesta 6, Ljubljana 1000, Slovenia e-mail:
| | - Marija Hribernik
- Medical Faculty, University of Ljubljana, Vrazov trg 2, Ljubljana 1000, Slovenia e-mail:
| | - Ivan Prebil
- Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva cesta 6, Ljubljana 1000, Slovenia e-mail:
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Tomaszewska A, Lubowiecka I, Szymczak C, Smietański M, Meronk B, Kłosowski P, Bury K. Physical and mathematical modelling of implant-fascia system in order to improve laparoscopic repair of ventral hernia. Clin Biomech (Bristol, Avon) 2013; 28:743-51. [PMID: 23890712 DOI: 10.1016/j.clinbiomech.2013.06.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 06/18/2013] [Accepted: 06/19/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND This paper describes an investigation of biomechanical behaviour of hernia repair, which is focused on the selection of safe linking of certain type of implant with fascia in laparoscopic operation. The strength of various fixations of the implant to the fascia is analysed. METHODS The research is based on experimental observations of operated hernia model behaviour during a dynamic impulse load corresponding to post-operative cough. Fifty seven different types of models of implanted mesh are considered. Five types of implants and five types of connectors are used. Mechanical properties of the implants as well as limit tearing forces of joints are identified in uni-axial tensile tests. Mathematical model of implanted mesh based on finite element method is proposed. The identified mechanical properties of the materials are applied and the model is calibrated using quantities measured during experiments. FINDINGS The presented results point at trans-abdominal sutures and ProTacks (connectors) and at DynaMesh (implant) as the most reliable materials used in ventral hernia operation, in the tested materials group. Desired properties of implants seem to be: elastic properties similar to the properties of tissues and high local strength, as fixation have a local character. The proposed mathematical model can be applied to simulate real behaviour of an implant with appropriate accuracy and to estimate the number of tacks for the implantation of hernia meshes. INTERPRETATION The presented results may help in the deeper understanding of the fascia-mesh system behaviour, and thus may lead to improve the fixation methods.
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Affiliation(s)
- A Tomaszewska
- Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, Department of Structural Mechanics and Bridge Structures, Narutowicza 11/12, 80-233 Gdańsk, Poland.
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Hernández-Gascón B, Peña E, Grasa J, Pascual G, Bellón JM, Calvo B. Mechanical Response of the Herniated Human Abdomen to the Placement of Different Prostheses. J Biomech Eng 2013; 135:51004. [DOI: 10.1115/1.4023703] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 02/19/2013] [Indexed: 01/02/2023]
Abstract
This paper describes a method designed to model the repaired herniated human abdomen just after surgery and examine its static mechanical response to the maximum intra-abdominal pressure provoked by a physiological movement (standing cough). The model is based on the real geometry of the human abdomen bearing a large incisional hernia with several anatomical structures differentiated by MRI. To analyze the outcome of hernia repair, the surgical procedure was simulated by modeling a prosthesis placed over the hernia. Three surgical meshes with different mechanical properties were considered: an isotropic heavy-weight mesh (Surgipro®), a slightly anisotropic light-weight mesh (Optilene®), and a highly anisotropic medium-weight mesh (Infinit®). Our findings confirm that anisotropic implants need to be positioned such that the most compliant axis of the mesh coincides with the craneo-caudal direction of the body.
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Affiliation(s)
| | | | - Jorge Grasa
- Associate Professor e-mail: Aragón Institute of Engineering Research (I3A), University of Zaragoza, CIBER-BBN, Centro de Investigación en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza 50018, Spain
| | - Gemma Pascual
- Associate Professor Faculty of Medicine, Department of Medical Specialities, University of Alcalá, CIBER-BBN, Centro de Investigación en Red en Bioingeniería, Biomateriales y Nanomedicina, Alcalá 28871, Spain e-mail:
| | - Juan M. Bellón
- Professor Faculty of Medicine, Department of Surgery, University of Alcalá, CIBER-BBN, Centro de Investigación en Red en Bioingeniería, Biomateriales y Nanomedicina, Alcalá 28871, Spain e-mail:
| | - Begoña Calvo
- Professor Aragón Institute of Engineering Research (I3A), University of Zaragoza, CIBER-BBN, Centro de Investigación en Red en Bioingeniería, Biomateriales y Nanomedicina, Zaragoza 50018, Spain e-mail:
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Effect of two loading rates on the elasticity of the human anterior rectus sheath. J Mech Behav Biomed Mater 2013; 20:1-5. [DOI: 10.1016/j.jmbbm.2012.12.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 12/10/2012] [Indexed: 11/23/2022]
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Hernández-Gascón B, Mena A, Peña E, Pascual G, Bellón JM, Calvo B. Understanding the Passive Mechanical Behavior of the Human Abdominal Wall. Ann Biomed Eng 2012; 41:433-44. [DOI: 10.1007/s10439-012-0672-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 09/29/2012] [Indexed: 02/05/2023]
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