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Academic literature on the topic 'Perichondrium; collagen fibers; biomechanical properties'
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Journal articles on the topic "Perichondrium; collagen fibers; biomechanical properties"
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Qin, Ting Wu, Shujiang Zhang, Zhi Ming Yang, Xiang Tao Mo, and Xiu Qun Li. "Mechanical Properties and Related Histological Alterations of Engineered Tendons In Vivo." Key Engineering Materials 288-289 (June 2005): 11–14. http://dx.doi.org/10.4028/www.scientific.net/kem.288-289.11.
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The purpose of this research is to find out the interaction between histological alterations and mechanical properties of engineered tendon implanted in situ. Defects of 0.5cm-1.0cm were made at deep flexor tendons by surgical procedure. Engineered tendons using degradable scaffolds polyglytic acid (PGA) mesh and tendon cells were implanted to repair the defects. Chickens were killed respectively at 2 weeks, 4 weeks, 6 weeks, and 8 weeks after surgery. The implants were taken out for histological examination, biomechanical test, and collagen synthesis assay. The results showed that after surgery the PGA scaffolds degraded fast and took precedence of collagen synthesis. There were not enough amount and maturation of the collagen fibers of the new tendon at 2-8 weeks after surgery. The biomechanical properties of new tendons were less than those of the normal tendon. Therefore, it is necessary to construct engineered tendons with better degradation rate of scaffolds and suitable biomechanical stimulation so that more collagen synthesis and better biomechanical properties of new tendons can be developed early after implantation.
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Uchiyama, Eiichi, Harold B. Kitaoka, Zong-Ping Luo, Joseph P. Grande, Hideji Kura, and Kai-Nan An. "Pathomechanics of Hallux Valgus: Biomechanical and Immunohistochemical Study." Foot & Ankle International 26, no. 9 (2005): 732–38. http://dx.doi.org/10.1177/107110070502600911.
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Background: One factor believed to contribute to the development of hallux valgus is an abnormality in collagen structure and makeup of the medial collateral ligament (MCL) of the first metatarsophalangeal joint (MTPJ). We hypothesized that the mechanical properties of the MCL in feet with hallux valgus are significantly different from those in normal feet and that these differences may be related to alterations in the type or distribution of collagen fibers at the interface between the MCL and the bone. Materials and Methods: Seven normal fresh-frozen cadaver feet were compared to four cadaver feet that had hallux valgus deformities. The MCL mechanical properties, structure of collagen fibers, and content proportion of type I and type III collagen were determined. Results: The load-deformation and stress-strain curves were curvilinear with three regions: laxity, toe, and linear regions. Laxity of the MCL in feet with hallux valgus was significantly larger than that of normal feet ( p = 0.022). Stiffness and tensile modulus in the toe region in feet with hallux valgus were significantly smaller than those in normal feet ( p = 0.004); however, stiffness and tensile modulus in the linear region were not significantly different. The MCL collagen fibrils in the feet with hallux valgus had a more wavy distribution than the fibrils in the normal feet. Conclusions: In general, strong staining for collagen III and to a lesser extent, collagen I was observed at the interface between the MCL and bone in the feet with hallux valgus but not in the normal feet. These results indicate that the abnormal mechanical properties of the MCL in feet with hallux valgus may be related to differences in the organization of collagen I and collagen III fibrils.
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HUANG, HSIAO-YING SHADOW, SIYAO HUANG, COLIN P. FRAZIER, PETER M. PRIM, and OLA HARRYSSON. "DIRECTIONAL BIOMECHANICAL PROPERTIES OF PORCINE SKIN TISSUE." Journal of Mechanics in Medicine and Biology 14, no. 05 (2014): 1450069. http://dx.doi.org/10.1142/s0219519414500699.
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Skin is a multilayered composite material and composed principally of the proteins collagen, elastic fibers and fibroblasts. The direction-dependent material properties of skin tissue is important for physiological functions like skin expansion. The current study has developed methods to characterize the directional biomechanical properties of porcine skin tissues as studies have shown that pigs represent a useful animal model due to similarities between porcine and human skin. It is observed that skin tissue has a nonlinear anisotropy biomechanical behavior, where the parameters of material modulus is 378 ± 160 kPa in the preferred-fiber direction and 65.96 ± 40.49 kPa in the cross-fiber direction when stretching above 30% strain equibiaxially. The result from the study provides methods of characterizing biaxial mechanical properties of skin tissue, as the collagen fiber direction appears to be one of the primary determinants of tissue anisotropy.
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Tanaka, Eiji, and Theo van Eijden. "Biomechanical Behavior of the Temporomandibular Joint Disc." Critical Reviews in Oral Biology & Medicine 14, no. 2 (2003): 138–50. http://dx.doi.org/10.1177/154411130301400207.
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The temporomandibular joint (TMJ) disc consists mainly of collagen fibers and proteoglycans constrained in the interstices of the collagen fiber mesh. This construction results in a viscoelastic response of the disc to loading and enables the disc to play an important role as a stress absorber during function. The viscoelastic properties depend on the direction (tension, compression, and shear) and the type of the applied loading (static and dynamic). The compressive elastic modulus of the disc is smaller than its tensile one because the elasticity of the disc is more dependent on the collagen fibers than on the proteoglycans. When dynamic loading occurs, the disc is likely to behave less stiffly than under static loading because of the difference of fluid flow through and out of the disc during loading. In addition, the mechanical properties change as a result of various intrinsic and extrinsic factors in life such as aging, trauma, and pathology. Information about the viscoelastic behavior of the disc is required for its function to be understood and, for instance, for a suitable TMJ replacement device to be constructed. In this review, the biomechanical behavior of the disc in response to different loading conditions is discussed.
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Vega-Estrada, Alfredo, Joaquin Silvestre-Albero, Alejandra E. Rodriguez, et al. "Biocompatibility and Biomechanical Effect of Single Wall Carbon Nanotubes Implanted in the Corneal Stroma: A Proof of Concept Investigation." Journal of Ophthalmology 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/4041767.
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Corneal ectatic disorders are characterized by a progressive weakening of the tissue due to biomechanical alterations of the corneal collagen fibers. Carbon nanostructures, mainly carbon nanotubes (CNTs) and graphene, are nanomaterials that offer extraordinary mechanical properties and are used to increase the rigidity of different materials and biomolecules such as collagen fibers. We conducted an experimental investigation where New Zealand rabbits were treated with a composition of CNTs suspended in balanced saline solution which was applied in the corneal tissue. Biocompatibility of the composition was assessed by means of histopathology analysis and mechanical properties by stress-strain measurements. Histopathology samples stained with blue Alcian showed that there were no fibrous scaring and no alterations in the mucopolysaccharides of the stroma. It also showed that there were no signs of active inflammation. These were confirmed when Masson trichrome staining was performed. Biomechanical evaluation assessed by means of tensile test showed that there is a trend to obtain higher levels of rigidity in those corneas implanted with CNTs, although these changes are not statistically significant (p>0.05). Implanting CNTs is biocompatible and safe procedure for the corneal stroma which can lead to an increase in the rigidity of the collagen fibers.
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CILINGIR, AHMET C. "EFFECTS OF CULTURE PERIODS AND LOADING ON BIOMECHANICAL PROPERTIES OF SHEEP COLLAGEN FASCICLES." Journal of Mechanics in Medicine and Biology 14, no. 06 (2014): 1440010. http://dx.doi.org/10.1142/s0219519414400107.
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Soft tissues (e.g., tendon, skin, cartilage) change their dimensions and properties in response to applied mechanical stress/strain, which is called remodeling. Experimental studies using tissue cultures were performed to understand the biomechanical properties of collagen fascicles under mechanical loads. Collagen fascicles were dissected from sheep Achilles tendons and loaded under 1, 2, and 3 kg for 2, 4, and 6 days under culture. The mechanical properties of collagen fascicles after being loaded into the culture media were determined using tensile tester, and resultant stress–strain curves, tangent modulus, tensile strength, and strain at failure values were compared with those in a non-loaded and non-cultured control group of fascicles. The tangent modulus and tensile strength of the collagen fascicles increased with the increasing remodeling load after two days of culture. However, these values gradually decreased with the increasing culture period compared with the control group. According to the results obtained in this study, the mechanical properties of collagen fascicles were improved by loading at two days of culture, most likely due to the remodeling of collagen fibers. However, after a period of remodeling, local strains on the collagen fibrils increased, and finally, the collagen fibrils broke down, decreasing the mechanical properties of the tissue.
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Brecs, Ivars, Sandra Skuja, Vladimir Kasyanov, et al. "From Biomechanical Properties to Morphological Variations: Exploring the Interplay between Aortic Valve Cuspidity and Ascending Aortic Aneurysm." Journal of Clinical Medicine 13, no. 14 (2024): 4225. http://dx.doi.org/10.3390/jcm13144225.
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Background: This research explores the biomechanical and structural characteristics of ascending thoracic aortic aneurysms (ATAAs), focusing on the differences between bicuspid aortic valve aneurysms (BAV-As) and tricuspid aortic valve aneurysms (TAV-As) with non-dilated aortas to identify specific traits of ATAAs. Methods: Clinical characteristics, laboratory indices, and imaging data from 26 adult patients operated on for aneurysms (BAV-A: n = 12; TAV-A: n = 14) and 13 controls were analyzed. Biomechanical parameters (maximal aortic diameter, strain, and stress) and structural analyses (collagen fiber organization, density, fragmentation, adipocyte deposits, and immune cell infiltration) were assessed. Results: Significant differences in biomechanical parameters were observed. Median maximal strain was 40.0% (control), 63.4% (BAV-A), and 45.3% (TAV-A); median maximal stress was 0.59 MPa (control), 0.78 MPa (BAV-A), and 0.48 MPa (TAV-A). BAV-A showed higher tangential modulus and smaller diameter, with substantial collagen fragmentation (p < 0.001 vs. TAV and controls). TAV-A exhibited increased collagen density (p = 0.025), thickening between media and adventitia layers, and disorganized fibers (p = 0.036). BAV-A patients had elevated adipocyte deposits and immune cell infiltration. Conclusions: This study highlights distinct pathological profiles associated with different valve anatomies. BAV-A is characterized by smaller diameters, higher biomechanical stress, and significant collagen deterioration, underscoring the necessity for tailored clinical strategies for effective management of thoracic aortic aneurysm.
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Cunnane, Eoghan M., Aneesh K. Ramaswamy, Katherine L. Lorentz, David A. Vorp, and Justin S. Weinbaum. "Extracellular Vesicles Derived from Primary Adipose Stromal Cells Induce Elastin and Collagen Deposition by Smooth Muscle Cells within 3D Fibrin Gel Culture." Bioengineering 8, no. 5 (2021): 51. http://dx.doi.org/10.3390/bioengineering8050051.
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Macromolecular components of the vascular extracellular matrix (ECM), particularly elastic fibers and collagen fibers, are critical for the proper physiological function of arteries. When the unique biomechanical combination of these fibers is disrupted, or in the ultimate extreme where fibers are completely lost, arterial disease can emerge. Bioengineers in the realms of vascular tissue engineering and regenerative medicine must therefore ideally consider how to create tissue engineered vascular grafts containing the right balance of these fibers and how to develop regenerative treatments for situations such as an aneurysm where fibers have been lost. Previous work has demonstrated that the primary cells responsible for vascular ECM production during development, arterial smooth muscle cells (SMCs), can be induced to make new elastic fibers when exposed to secreted factors from adipose-derived stromal cells. To further dissect how this signal is transmitted, in this study, the factors were partitioned into extracellular vesicle (EV)-rich and EV-depleted fractions as well as unseparated controls. EVs were validated using electron microscopy, dynamic light scattering, and protein quantification before testing for biological effects on SMCs. In 2D culture, EVs promoted SMC proliferation and migration. After 30 days of 3D fibrin construct culture, EVs promoted SMC transcription of the elastic microfibril gene FBN1 as well as SMC deposition of insoluble elastin and collagen. Uniaxial biomechanical properties of strand fibrin constructs were no different after 30 days of EV treatment versus controls. In summary, it is apparent that some of the positive effects of adipose-derived stromal cells on SMC elastogenesis are mediated by EVs, indicating a potential use for these EVs in a regenerative therapy to restore the biomechanical function of vascular ECM in arterial disease.
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Wang, X. D., S. J. Cui, Y. Liu, et al. "Deterioration of Mechanical Properties of Discs in Chronically Inflamed TMJ." Journal of Dental Research 93, no. 11 (2014): 1170–76. http://dx.doi.org/10.1177/0022034514552825.
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Temporomandibular joint (TMJ) discs frequently undergo degenerative changes in arthritis. However, the biomechanical properties of pathogenic discs remain to be explored. In this study, we evaluated the effects of chronic inflammation on the biomechanical properties of TMJ discs in rats. Chronic inflammation of TMJs was induced by double intra-articular injections of complete Freund’s adjuvant for 5 weeks, and biomechanical properties and ultrastructure of the discs were examined by mechanical testing, scanning electron microscopy, and transmission electron microscopy. The instantaneous compressive moduli of the anterior and posterior bands of discs in inflamed TMJs were decreased significantly compared with those in the control group. The instantaneous tensile moduli of the discs of inflamed TMJs also showed significant decreases in both the anterior-posterior and mesial-lateral directions. The relaxation moduli of the discs of inflamed TMJs showed nearly the same tendency as the instantaneous moduli. The surfaces of the discs of inflamed TMJs became rough and porous due to the loss of the superficial gel-like stratum, with many collagen fibers exposed and degradation of the sub-superficial collagen fibrils. Our results suggested that chronic inflammation of TMJ could lead to deterioration of mechanical properties and alteration of disc ultrastructure, which might contribute to TMJ disc displacement.
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Wullkopf, Lena, Ann-Katrine V. West, Natascha Leijnse, et al. "Cancer cells’ ability to mechanically adjust to extracellular matrix stiffness correlates with their invasive potential." Molecular Biology of the Cell 29, no. 20 (2018): 2378–85. http://dx.doi.org/10.1091/mbc.e18-05-0319.
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Increased tissue stiffness is a classic characteristic of solid tumors. One of the major contributing factors is increased density of collagen fibers in the extracellular matrix (ECM). Here, we investigate how cancer cells biomechanically interact with and respond to the stiffness of the ECM. Probing the adaptability of cancer cells to altered ECM stiffness using optical tweezers–based microrheology and deformability cytometry, we find that only malignant cancer cells have the ability to adjust to collagen matrices of different densities. Employing microrheology on the biologically relevant spheroid invasion assay, we can furthermore demonstrate that, even within a cluster of cells of similar origin, there are differences in the intracellular biomechanical properties dependent on the cells’ invasive behavior. We reveal a consistent increase of viscosity in cancer cells leading the invasion into the collagen matrices in comparison with cancer cells following in the stalk or remaining in the center of the spheroid. We hypothesize that this differential viscoelasticity might facilitate spheroid tip invasion through a dense matrix. These findings highlight the importance of the biomechanical interplay between cells and their microenvironment for tumor progression.
Conference papers on the topic "Perichondrium; collagen fibers; biomechanical properties"
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Murphy, Colm, Denis Kelliher, and John Davenport. "A Nonlinear Finite Element Inverse Approach to Characterize the Material Properties of Tracheal Cartilage: Preliminary Study." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19538.
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Tracheal cartilage is a form of hyaline cartilage. Mature hyaline cartilage is classified by miniature aggregations of chondrocytes implanted in an amorphous matrix of ground substance reinforced by collagen fibres designated as collagen type II. The adjacent layer, the perichondrium, consists of collagen fibers and spindle-shaped cells which are similar to fibroblasts. It has been determined that collagen is a nonlinear material[1], and consequently, tracheal cartilage is also nonlinear. Previous research on tracheal cartilage has treated the material as both linear and nonlinear[2].
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Huang, Hsiao-Ying Shadow, Siyao Huang, Taylor Gettys, Peter M. Prim, and Ola L. Harrysson. "A Biomechanical Study of Directional Mechanical Properties of Porcine Skin Tissues." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63829.
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Skin is a multilayered composite material and composed principally of the proteins collagen, elastic fibers, and fibroblasts. The direction-dependent material properties of skin tissue is important for physiological functions like skin expansion. The current study has developed methods to characterize the directional biomechanical properties of porcine skin tissues. It is observed that skin tissue has a nonlinear anisotropy biomechanical behavior, where the parameters of material stiffness is 378 ±160 kPa in the preferred-fiber direction and 65.96±40.49 kPa in the cross-fiber direction when stretching above 30% strain equibiaxially. The results from the current study will help optimize functional skin stretching for patients requiring large surface area skin grafts and reconstructions due to burns or other injuries.
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Huang, Hsiao-Ying Shadow, Brittany N. Balhouse, and Siyao Huang. "A Biomechanical and Biochemical Synergy Study of Heart Valve Tissue." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-87997.
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The function of heart valves is to allow blood to flow through the heart smoothly and to prevent retrograde flow of blood. Previous studies have shown that the mechanical properties of heart valve tissues, microstructures of extracellular matrix, and collagen concentrations are the keys to the healthy heart valves and, therefore, are crucial to the development of viable tissue-engineered heart valve replacements. Therefore, this study investigates the relationship between these factors in native porcine aortic and pulmonary valves and provides insights to the healthy heart valves. Heart valve leaflets are prepared for biaxial stretching to obtain mechanical properties. The average collagen concentrations of heart valve leaflets are determined via an assay kit. The results indicate that aortic valves are stiffer than pulmonary valves macroscopically and stiffness varies more in the circumferential direction for the aortic valve than it does for the pulmonary valve. Microscopically, it is due to collagen fibers in aortic valves are more in alignment than ones in pulmonary valves, which are more randomly in direction. Collagen assay results show that collagen concentrations are higher in the edges of pulmonary valves than in aortic valves. The results also suggest the duration of extraction may have significant affects on the concentration results. This work provides quantified stress and strain environment within heart valve tissues to help further studies on how to treat heart valve disease and create more viable heart valve replacements.
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Connizzo, Brianne K., Kenneth W. Liechty, and Louis J. Soslowsky. "Altered Mechanical Properties and Fiber Re-Alignment in Diabetic Mouse Supraspinatus and Achilles Tendons." In ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80129.
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Tendons function to transfer load, maintain alignment and permit motion in joints. To perform these functions, tendons have complex mechanical behavior which is modulated by the tissue’s structure and composition, such as the collagen fibers and surrounding extracellular matrix. When these matrix proteins are altered, the mechanical properties are also altered, which could potentially lead to reduced loading and healing capacity. Diabetes is a metabolic disease which, among other co-morbidities, has been associated with Achilles tendon disorganization and tendinopathy, as well as increased overall joint stiffness in humans [1]. We have recently reported that the skin from the Db/Db diabetic mouse, a model of Type II Diabetes, as well as the skin from human diabetics, have impaired biomechanical properties compared to non-diabetic skin as the result of altered extracellular matrix composition. [2]. However, the mechanical properties of tendons from these animals have never been studied and could serve as a unique model of altered collagen structure as well as provide further understanding to the cause of tendinous injuries in the diabetic population. Therefore, the objective of this study is to measure the tensile mechanical properties and collagen fiber re-alignment in the db/db mouse model compared to non-diabetic controls. We hypothesize that tendon stiffness and modulus will be increased in the db/db group in the insertion site and midsubstance, and that db/db tendons will re-align earlier and faster during the testing protocol.
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Komolafe, Oluseeni A., and Todd C. Doehring. "Nonlinear Elastic Behavior of Achilles Tendon at the Fascicle Scale." In ASME 2007 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2007. http://dx.doi.org/10.1115/sbc2007-176880.
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Parallel collagen fibers such as ligaments and tendons are composed of fiber bundles, or fascicles, enclosed in a sheath of reticular membrane. In the Achilles tendon, these fascicles can be long, extending from the gastro-soleus unit to the calcaneal insertion site (Fig. 1). Although the overall functional behavior of the whole tendon is well established[1], there is little information detailing properties of individual fascicles or their interactions. Knowledge of the structural and biomechanical properties at the “mesostructural” scale (i.e. fascicle-scale) is critical to understanding tissue pathologies; in particular the processes involved in injury and healing, and the development of improved computational models and functional tissue engineered constructs.
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Hatami-Marbini, Hamed, and Peter M. Pinsky. "Electrostatic Contribution of the Proteoglycans to the In-Plane Shear and Compressive Stiffness of Corneal Stroma." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19191.
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The extracellular matrix (ECM) is a fibrous structure embedded in an aqueous gel. The mechanical and electrostatic interactions of the ECM constituents, i.e. collagen fibers and proteoglycans (PGs), define the structure and mechanical response of connective tissues (CTs) such as cornea and articular cartilage. Proteoglycans are complex macromolecules consisting of linear chains of repeating gylcosaminoglycans (GAGs) which are covalently attached to a core protein. PGs can be as simple as decorin with a single GAG side chain or as complex as aggrecan with many GAGs. Decorin is the simplest small leucine-rich PG and is the main PG inside the corneal stroma. It has an arch shape and links non-covalently at its concave surface to the collagen fibrils. It has been shown that while collagen fibers inside the extracellular matrix resist the tensile forces, the negatively charged glycosaminoglycans and their interaction with water give compressive stiffness to the tissue. The role of PGs in biomechanical properties of the connective tissues has mainly been studied in order to explore the behavior of articular cartilage [1], which is a CT with large and highly negatively charged PGs, aggrecans. In order to explain the role of PGs in this tissue, it is commonly assumed that their contribution to the CT elasticity is because of both the repulsive forces between negatively charged GAGs and GAG interactions with free mobile charges in the ionic bath. The electrostatic contribution to the shear and compressive stiffness of cartilage is modeled by approximating GAGs as charged rods [1]. The Poisson-Boltzmann equation is used to compute the change in electrical potential and mobile ion distributions which are caused by the macroscopic deformation.
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Prantil, Ryan K., Tracy A. Mondello, Suk H. Yu, Khurram Pervaiz, Savio L.-Y. Woo, and Zong-Ming Li. "Stiffness of the Transverse Carpal Ligament Under the Influence of Collagenase." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53284.
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Forming the palmar roof of the carpal tunnel, the transverse carpal ligament (TCL) continues to be the surgical target for carpal tunnel release which aims to relieve the symptoms of patients with carpal tunnel syndrome. However, the surgical procedures may cause several biomechanical and anatomical problems for the carpal tunnel [1]. Therefore, an alternative, aimed at preserving the TCL, might alleviate patients’ post-operative complications. Using a geometrical model, Li et al. showed that the cross-sectional area of the carpal tunnel can be effectively increased by TCL elongation [2]. Theoretically, stiffness reduction could facilitate a ligament’s capability to elongate. Past studies have shown that the utilization of the collagenase enzyme altered the mechanical properties of a soft tissue [3, 4]. It also has been used to treat Dupuytren’s Contracture [5] because collagenase breaks the peptide bonds within collagen fibers [6]. The usage of collagenase could effectively reduce the stiffness of the TCL allowing for the ligament to elongate and for the median nerve to decompress. Thus, the purpose of our study is to determine the effect of collagenase on the stiffness of the TCL. We hypothesize that the stiffness of the ligament will progressively decrease due to the enzymatic effect of collagenase.