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Linus A, Tanska P, Nippolainen E, Tiitu V, Töyras J, Korhonen RK, Afara IO, Mononen ME. Site-specific elastic and viscoelastic biomechanical properties of healthy and osteoarthritic human knee joint articular cartilage. J Biomech 2024; 169:112135. [PMID: 38744145 DOI: 10.1016/j.jbiomech.2024.112135] [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: 08/21/2023] [Revised: 04/07/2024] [Accepted: 05/02/2024] [Indexed: 05/16/2024]
Abstract
Articular cartilage exhibits site-specific biomechanical properties. However, no study has comprehensively characterized site-specific cartilage properties from the same knee joints at different stages of osteoarthritis (OA). Cylindrical osteochondral explants (n = 381) were harvested from donor-matched lateral and medial tibia, lateral and medial femur, patella, and trochlea of cadaveric knees (N = 17). Indentation test was used to measure the elastic and viscoelastic mechanical properties of the samples, and Osteoarthritis Research Society International (OARSI) grading system was used to categorize the samples into normal (OARSI 0-1), early OA (OARSI 2-3), and advanced OA (OARSI 4-5) groups. OA-related changes in cartilage mechanical properties were site-specific. In the lateral and medial tibia and trochlea sites, equilibrium, instantaneous and dynamic moduli were higher (p < 0.001) in normal tissue than in early and advanced OA tissue. In lateral and medial femur, equilibrium, instantaneous and dynamic moduli were smaller in advanced OA, but not in early OA, than in normal tissue. The phase difference (0.1-0.25 Hz) between stress and strain was significantly smaller (p < 0.05) in advanced OA than in normal tissue across all sites except medial tibia. Our results indicated that in contrast to femoral and patellar cartilage, equilibrium, instantaneous and dynamic moduli of the tibia and trochlear cartilage decreased in early OA. These may suggest that the tibia and trochlear cartilage degrades faster than the femoral and patellar cartilage. The information is relevant for developing site-specific computational models and engineered cartilage constructs.
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Affiliation(s)
- Awuniji Linus
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland.
| | - Petri Tanska
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Ervin Nippolainen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Virpi Tiitu
- Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
| | - Juha Töyras
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland; Science Service Center, Kuopio University Hospital, Kuopio, Finland; School of Electrical Engineering and Computer Science, The University of Queensland, Brisbane, Australia
| | - Rami K Korhonen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Isaac O Afara
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Mika E Mononen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
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2
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Okada S, Taniguchi M, Yagi M, Motomura Y, Okada S, Nakazato K, Fukumoto Y, Kobayashi M, Kanemitsu K, Ichihashi N. Characteristics of Acute Cartilage Response After Mechanical Loading in Patients with Early-Mild Knee Osteoarthritis. Ann Biomed Eng 2024; 52:1326-1334. [PMID: 38329562 DOI: 10.1007/s10439-024-03456-6] [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: 09/12/2023] [Accepted: 01/17/2024] [Indexed: 02/09/2024]
Abstract
This study determined whether the acute cartilage response, assessed by cartilage thickness and echo intensity, differs between patients with early-mild knee osteoarthritis (OA) and healthy controls. We recruited 56 women aged ≥ 50 years with Kellgren-Lawrence (KL) grade ≤ 2 (age, 70.6 ± 7.4 years; height, 153.7 ± 5.2 cm; weight, 51.9 ± 8.2 kg). Based on KL grades and knee symptoms, the participants were classified into control (KL ≤ 1, asymptomatic, n = 27) and early-mild knee OA groups (KL 1 and symptomatic, KL 2, n = 29). Medial femoral cartilage thickness and echo intensity were assessed using ultrasonographic B-mode images before and after treadmill walking (15 min, 3.3 km/h). To investigate the acute cartilage response, repeated-measures analysis of covariance (groups × time) with adjusted age, external knee moment impulse, steps during treadmill walking, and cartilage thickness at pre-walking was performed. A significant interaction was found at the tibiofemoral joint; after walking, the cartilage thickness was significantly decreased in the early-mild knee OA group compared to the control group (p = 0.002). At the patellofemoral joint, a significant main effect of time was observed, but no interaction was detected (p = 0.802). No changes in cartilage echo intensity at either the tibiofemoral or patellofemoral joints, and no interactions were noted (p = 0.295 and p = 0.063). As acute cartilage response after walking, the thickness of the medial tibiofemoral joint in the early-mild knee OA was significantly reduced than that in the control group. Thus, greater acute deformation after walking might be a feature found in patients with early-mild knee OA.
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Affiliation(s)
- Shogo Okada
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
- Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan
| | - Masashi Taniguchi
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
| | - Masahide Yagi
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Yoshiki Motomura
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
- Kobayashi Orthopaedic Clinic, Kyoto, Japan
| | - Sayaka Okada
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Kaede Nakazato
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Yoshihiro Fukumoto
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
- Faculty of Rehabilitation, Kansai Medical University, Osaka, Japan
| | | | | | - Noriaki Ichihashi
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
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Berni M, Marchiori G, Baleani M, Giavaresi G, Lopomo NF. Biomechanics of the Human Osteochondral Unit: A Systematic Review. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1698. [PMID: 38612211 PMCID: PMC11012636 DOI: 10.3390/ma17071698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 03/17/2024] [Accepted: 03/26/2024] [Indexed: 04/14/2024]
Abstract
The damping system ensured by the osteochondral (OC) unit is essential to deploy the forces generated within load-bearing joints during locomotion, allowing furthermore low-friction sliding motion between bone segments. The OC unit is a multi-layer structure including articular cartilage, as well as subchondral and trabecular bone. The interplay between the OC tissues is essential in maintaining the joint functionality; altered loading patterns can trigger biological processes that could lead to degenerative joint diseases like osteoarthritis. Currently, no effective treatments are available to avoid degeneration beyond tissues' recovery capabilities. A thorough comprehension on the mechanical behaviour of the OC unit is essential to (i) soundly elucidate its overall response to intra-articular loads for developing diagnostic tools capable of detecting non-physiological strain levels, (ii) properly evaluate the efficacy of innovative treatments in restoring physiological strain levels, and (iii) optimize regenerative medicine approaches as potential and less-invasive alternatives to arthroplasty when irreversible damage has occurred. Therefore, the leading aim of this review was to provide an overview of the state-of-the-art-up to 2022-about the mechanical behaviour of the OC unit. A systematic search is performed, according to PRISMA standards, by focusing on studies that experimentally assess the human lower-limb joints' OC tissues. A multi-criteria decision-making method is proposed to quantitatively evaluate eligible studies, in order to highlight only the insights retrieved through sound and robust approaches. This review revealed that studies on human lower limbs are focusing on the knee and articular cartilage, while hip and trabecular bone studies are declining, and the ankle and subchondral bone are poorly investigated. Compression and indentation are the most common experimental techniques studying the mechanical behaviour of the OC tissues, with indentation also being able to provide information at the micro- and nanoscales. While a certain comparability among studies was highlighted, none of the identified testing protocols are currently recognised as standard for any of the OC tissues. The fibril-network-reinforced poro-viscoelastic constitutive model has become common for describing the response of the articular cartilage, while the models describing the mechanical behaviour of mineralised tissues are usually simpler (i.e., linear elastic, elasto-plastic). Most advanced studies have tested and modelled multiple tissues of the same OC unit but have done so individually rather than through integrated approaches. Therefore, efforts should be made in simultaneously evaluating the comprehensive response of the OC unit to intra-articular loads and the interplay between the OC tissues. In this regard, a multidisciplinary approach combining complementary techniques, e.g., full-field imaging, mechanical testing, and computational approaches, should be implemented and validated. Furthermore, the next challenge entails transferring this assessment to a non-invasive approach, allowing its application in vivo, in order to increase its diagnostic and prognostic potential.
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Affiliation(s)
- Matteo Berni
- Laboratorio di Tecnologia Medica, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy; (M.B.); (M.B.)
| | - Gregorio Marchiori
- Scienze e Tecnologie Chirurgiche, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy;
| | - Massimiliano Baleani
- Laboratorio di Tecnologia Medica, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy; (M.B.); (M.B.)
| | - Gianluca Giavaresi
- Scienze e Tecnologie Chirurgiche, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy;
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Orava H, Paakkari P, Jäntti J, Honkanen MKM, Honkanen JTJ, Virén T, Joenathan A, Tanska P, Korhonen RK, Grinstaff MW, Töyräs J, Mäkelä JTA. Triple contrast computed tomography reveals site-specific biomechanical differences in the human knee joint-A proof of concept study. J Orthop Res 2024; 42:415-424. [PMID: 37593815 DOI: 10.1002/jor.25683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/05/2023] [Accepted: 08/14/2023] [Indexed: 08/19/2023]
Abstract
Cartilage and synovial fluid are challenging to observe separately in native computed tomography (CT). We report the use of triple contrast agent (bismuth nanoparticles [BiNPs], CA4+, and gadoteridol) to image and segment cartilage in cadaveric knee joints with a clinical CT scanner. We hypothesize that BiNPs will remain in synovial fluid while the CA4+ and gadoteridol will diffuse into cartilage, allowing (1) segmentation of cartilage, and (2) evaluation of cartilage biomechanical properties based on contrast agent concentrations. To investigate these hypotheses, triple contrast agent was injected into both knee joints of a cadaver (N = 1), imaged with a clinical CT at multiple timepoints during the contrast agent diffusion. Knee joints were extracted, imaged with micro-CT (µCT), and biomechanical properties of the cartilage surface were determined by stress-relaxation mapping. Cartilage was segmented and contrast agent concentrations (CA4+ and gadoteridol) were compared with the biomechanical properties at multiple locations (n = 185). Spearman's correlation between cartilage thickness from clinical CT and reference µCT images verifies successful and reliable segmentation. CA4+ concentration is significantly higher in femoral than in tibial cartilage at 60 min and further timepoints, which corresponds to the higher Young's modulus observed in femoral cartilage. In this pilot study, we show that (1) large BiNPs do not diffuse into cartilage, facilitating straightforward segmentation of human knee joint cartilage in a clinical setting, and (2) CA4+ concentration in cartilage reflects the biomechanical differences between femoral and tibial cartilage. Thus, the triple contrast agent CT shows potential in cartilage morphology and condition estimation in clinical CT.
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Affiliation(s)
- Heta Orava
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Petri Paakkari
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Jiri Jäntti
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | - Miitu K M Honkanen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
| | | | - Tuomas Virén
- Center of Oncology, Kuopio University Hospital, Kuopio, Finland
| | - Anisha Joenathan
- Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University, Boston, Massachusetts, USA
| | - Petri Tanska
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Rami K Korhonen
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
| | - Mark W Grinstaff
- Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University, Boston, Massachusetts, USA
| | - Juha Töyräs
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Science Service Center, Kuopio University Hospital, Kuopio, Finland
- School of Electrical Engineering and Computer Science, The University of Queensland, Brisbane, Australia
| | - Janne T A Mäkelä
- Department of Technical Physics, University of Eastern Finland, Kuopio, Finland
- Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland
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5
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Ying H, Shen C, Pan R, Li X, Chen Y. Strategy insight: Mechanical properties of biomaterials' influence on hydrogel-mesenchymal stromal cell combination for osteoarthritis therapy. Front Pharmacol 2023; 14:1152612. [PMID: 37153763 PMCID: PMC10154526 DOI: 10.3389/fphar.2023.1152612] [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: 01/28/2023] [Accepted: 04/10/2023] [Indexed: 05/10/2023] Open
Abstract
Osteoarthritis (OA) is a kind of degenerative joint disease usually found in older adults and those who have received meniscal surgery, bringing great suffering to a number of patients worldwide. One of the major pathological features of OA is retrograde changes in the articular cartilage. Mesenchymal stromal cells (MSCs) can differentiate into chondrocytes and promote cartilage regeneration, thus having great potential for the treatment of osteoarthritis. However, improving the therapeutic effect of MSCs in the joint cavity is still an open problem. Hydrogel made of different biomaterials has been recognized as an ideal carrier for MSCs in recent years. This review focuses on the influence of the mechanical properties of hydrogels on the efficacy of MSCs in OA treatment and compares artificial materials with articular cartilage, hoping to provide a reference for further development of modified hydrogels to improve the therapeutic effect of MSCs.
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Affiliation(s)
- Haoli Ying
- Department of Genetics, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
- Department of Genetic and Metabolic Disease, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Genetic and Developmental Disorders, Institute of Genetics, Zhejiang University, Hangzhou, China
| | - Chengchun Shen
- Huzhou Basic and Clinical Translation of Orthopaedics Key Laboratory, Huzhou, China
- Department of Orthopedics, Huzhou Central Hospital, Zhejiang University Huzhou Hospital, Huzhou, China
| | - Ruolang Pan
- Zhejiang Provincial Key Laboratory of Cell-Based Drug and Applied Technology Development, Hangzhou, China
| | - Xiongfeng Li
- Huzhou Basic and Clinical Translation of Orthopaedics Key Laboratory, Huzhou, China
- Department of Orthopedics, Huzhou Central Hospital, Zhejiang University Huzhou Hospital, Huzhou, China
- *Correspondence: Xiongfeng Li, ; Ye Chen,
| | - Ye Chen
- Department of Genetics, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
- Department of Genetic and Metabolic Disease, The Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Genetic and Developmental Disorders, Institute of Genetics, Zhejiang University, Hangzhou, China
- *Correspondence: Xiongfeng Li, ; Ye Chen,
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Gonzalez-Fernandez P, Rodríguez-Nogales C, Jordan O, Allémann E. Combination of mesenchymal stem cells and bioactive molecules in hydrogels for osteoarthritis treatment. Eur J Pharm Biopharm 2022; 172:41-52. [PMID: 35114357 DOI: 10.1016/j.ejpb.2022.01.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 12/13/2021] [Accepted: 01/17/2022] [Indexed: 12/15/2022]
Abstract
Osteoarthritis (OA) is a chronic and inflammatory disease with no effective regenerative treatments to date. The therapeutic potential of mesenchymal stem cells (MSCs) remains to be fully explored. Intra-articular injection of these cells promotes cartilage protection and regeneration by paracrine signaling and differentiation into chondrocytes. However, joints display a harsh avascular environment for these cells upon injection. This phenomenon prompted researchers to develop suitable injectable materials or systems for MSCs to enhance their function and survival. Among them, hydrogels can absorb a large amount of water and maintain their 3D structure but also allow incorporation of bioactive agents or small molecules in their matrix that maximize the action of MSCs. These materials possess advantageous cartilage-like features such as collagen or hyaluronic acid moieties that interact with MSC receptors, thereby promoting cell adhesion. This review provides an up-to-date overview of the progress and opportunities of MSCs entrapped into hydrogels, combined with bioactive/small molecules to improve the therapeutic effects in OA treatment.
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Affiliation(s)
- P Gonzalez-Fernandez
- School of Pharmaceutical Sciences, University of Geneva, Rue Michel-Servet 1, 1211 Geneva, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, Rue Michel-Servet 1, 1211 Geneva 4, Switzerland
| | - C Rodríguez-Nogales
- School of Pharmaceutical Sciences, University of Geneva, Rue Michel-Servet 1, 1211 Geneva, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, Rue Michel-Servet 1, 1211 Geneva 4, Switzerland
| | - O Jordan
- School of Pharmaceutical Sciences, University of Geneva, Rue Michel-Servet 1, 1211 Geneva, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, Rue Michel-Servet 1, 1211 Geneva 4, Switzerland
| | - E Allémann
- School of Pharmaceutical Sciences, University of Geneva, Rue Michel-Servet 1, 1211 Geneva, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, Rue Michel-Servet 1, 1211 Geneva 4, Switzerland.
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7
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Pitta Kruize C, Panahkhahi S, Putra NE, Diaz-Payno P, van Osch G, Zadpoor AA, Mirzaali MJ. Biomimetic Approaches for the Design and Fabrication of Bone-to-Soft Tissue Interfaces. ACS Biomater Sci Eng 2021. [PMID: 34784181 DOI: 10.1021/acsbiomaterials.1c00620] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bone-to-soft tissue interfaces are responsible for transferring loads between tissues with significantly dissimilar material properties. The examples of connective soft tissues are ligaments, tendons, and cartilages. Such natural tissue interfaces have unique microstructural properties and characteristics which avoid the abrupt transitions between two tissues and prevent formation of stress concentration at their connections. Here, we review some of the important characteristics of these natural interfaces. The native bone-to-soft tissue interfaces consist of several hierarchical levels which are formed in a highly specialized anisotropic fashion and are composed of different types of heterogeneously distributed cells. The characteristics of a natural interface can rely on two main design principles, namely by changing the local microarchitectural features (e.g., complex cell arrangements, and introducing interlocking mechanisms at the interfaces through various geometrical designs) and changing the local chemical compositions (e.g., a smooth and gradual transition in the level of mineralization). Implementing such design principles appears to be a promising approach that can be used in the design, reconstruction, and regeneration of engineered biomimetic tissue interfaces. Furthermore, prominent fabrication techniques such as additive manufacturing (AM) including 3D printing and electrospinning can be used to ease these implementation processes. Biomimetic interfaces have several biological applications, for example, to create synthetic scaffolds for osteochondral tissue repair.
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Affiliation(s)
- Carlos Pitta Kruize
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Sara Panahkhahi
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Niko Eka Putra
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Pedro Diaz-Payno
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Gerjo van Osch
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Amir A Zadpoor
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Mohammad J Mirzaali
- Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands
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Elastic, Dynamic Viscoelastic and Model-Derived Fibril-Reinforced Poroelastic Mechanical Properties of Normal and Osteoarthritic Human Femoral Condyle Cartilage. Ann Biomed Eng 2021; 49:2622-2634. [PMID: 34341898 PMCID: PMC8455392 DOI: 10.1007/s10439-021-02838-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 07/15/2021] [Indexed: 12/27/2022]
Abstract
Osteoarthritis (OA) degrades articular cartilage and weakens its function. Modern fibril-reinforced poroelastic (FRPE) computational models can distinguish the mechanical properties of main cartilage constituents, namely collagen, proteoglycans, and fluid, thus, they can precisely characterize the complex mechanical behavior of the tissue. However, these properties are not known for human femoral condyle cartilage. Therefore, we aimed to characterize them from human subjects undergoing knee replacement and from deceased donors without known OA. Multi-step stress-relaxation measurements coupled with sample-specific finite element analyses were conducted to obtain the FRPE material properties. Samples were graded using OARSI scoring to determine the severity of histopathological cartilage degradation. The results suggest that alterations in the FRPE properties are not evident in the moderate stages of cartilage degradation (OARSI 2-3) as compared with normal tissue (OARSI 0-1). Drastic deterioration of the FRPE properties was observed in severely degraded cartilage (OARSI 4). We also found that the FRPE properties of femoral condyle cartilage related to the collagen network (initial fibril-network modulus) and proteoglycan matrix (non-fibrillar matrix modulus) were greater compared to tibial and patellar cartilage in OA. These findings may inform cartilage tissue-engineering efforts and help to improve the accuracy of cartilage representations in computational knee joint models.
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9
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Davis S, Roldo M, Blunn G, Tozzi G, Roncada T. Influence of the Mechanical Environment on the Regeneration of Osteochondral Defects. Front Bioeng Biotechnol 2021; 9:603408. [PMID: 33585430 PMCID: PMC7873466 DOI: 10.3389/fbioe.2021.603408] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 01/04/2021] [Indexed: 12/20/2022] Open
Abstract
Articular cartilage is a highly specialised connective tissue of diarthrodial joints which provides a smooth, lubricated surface for joint articulation and plays a crucial role in the transmission of loads. In vivo cartilage is subjected to mechanical stimuli that are essential for cartilage development and the maintenance of a chondrocytic phenotype. Cartilage damage caused by traumatic injuries, ageing, or degradative diseases leads to impaired loading resistance and progressive degeneration of both the articular cartilage and the underlying subchondral bone. Since the tissue has limited self-repairing capacity due its avascular nature, restoration of its mechanical properties is still a major challenge. Tissue engineering techniques have the potential to heal osteochondral defects using a combination of stem cells, growth factors, and biomaterials that could produce a biomechanically functional tissue, representative of native hyaline cartilage. However, current clinical approaches fail to repair full-thickness defects that include the underlying subchondral bone. Moreover, when tested in vivo, current tissue-engineered grafts show limited capacity to regenerate the damaged tissue due to poor integration with host cartilage and the failure to retain structural integrity after insertion, resulting in reduced mechanical function. The aim of this review is to examine the optimal characteristics of osteochondral scaffolds. Additionally, an overview on the latest biomaterials potentially able to replicate the natural mechanical environment of articular cartilage and their role in maintaining mechanical cues to drive chondrogenesis will be detailed, as well as the overall mechanical performance of grafts engineered using different technologies.
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Affiliation(s)
- Sarah Davis
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Marta Roldo
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Gordon Blunn
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Gianluca Tozzi
- Zeiss Global Centre, School of Mechanical and Design Engineering, University of Portsmouth, Portsmouth, United Kingdom
| | - Tosca Roncada
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, United Kingdom
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10
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Motavalli M, Jones C, Berilla JA, Li M, Schluchter MD, Mansour JM, Welter JF. Apparatus and Method for Rapid Detection of Acoustic Anisotropy in Cartilage. J Med Biol Eng 2020; 40:419-427. [PMID: 32494235 DOI: 10.1007/s40846-020-00518-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Purpose Articular cartilage is known to be mechanically anisotropic. In this paper, the acoustic anisotropy of bovine articular cartilage and the effects of freeze-thaw cycling on acoustic anisotropy were investigated. Methods We developed apparatus and methods that use a magnetic L-shaped sample holder, which allowed minimal handling of a tissue, reduced the number of measurements compared to previous studies, and produced highly reproducible results. Results SOS was greater in the direction perpendicular to the articular surface compared to the direction parallel to the articular surface (N=17, P = 0.00001). Average SOS was 1,758 ± 107 m/s perpendicular to the surface, and 1,617 ± 55 m/s parallel to it. The average percentage difference in SOS between the perpendicular and parallel directions was 8.2% (95% CI: 5.4% to 11%). Freeze-thaw cycling did not have a significant effect on SOS (P>0.4). Conclusion Acoustic measurement of tissue properties is particularly attractive for work in our laboratory since it has the potential for nondestructive characterization of the properties of developing engineered cartilage. Our approach allowed us to observe acoustic anisotropy of articular cartilage rapidly and reproducibly. This property was not significantly affected by freeze-thawing of the tissue samples, making cryopreservation practical for these assays.
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Affiliation(s)
- Mostafa Motavalli
- Department of Biology, Case Western Reserve University, all Cleveland, OH, USA.,Case Center for Multimodal Evaluation of Engineered Cartilage, Case Western Reserve University, all Cleveland, OH, USA
| | | | - Jim A Berilla
- Department of Civil Engineering, Case Western Reserve University, all Cleveland, OH, USA.,Case Center for Multimodal Evaluation of Engineered Cartilage, Case Western Reserve University, all Cleveland, OH, USA
| | - Ming Li
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, all Cleveland, OH, USA.,Case Center for Multimodal Evaluation of Engineered Cartilage, Case Western Reserve University, all Cleveland, OH, USA
| | - Mark D Schluchter
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, all Cleveland, OH, USA.,Case Center for Multimodal Evaluation of Engineered Cartilage, Case Western Reserve University, all Cleveland, OH, USA
| | - Joseph M Mansour
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University all Cleveland, OH, USA.,Case Center for Multimodal Evaluation of Engineered Cartilage, Case Western Reserve University, all Cleveland, OH, USA
| | - Jean F Welter
- Department of Biology, Case Western Reserve University, all Cleveland, OH, USA.,Case Center for Multimodal Evaluation of Engineered Cartilage, Case Western Reserve University, all Cleveland, OH, USA
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11
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Evrard L, Audigié F, Bertoni L, Jacquet S, Denoix JM, Busoni V. Low field magnetic resonance imaging of the equine distal interphalangeal joint: Comparison between weight-bearing and non-weight-bearing conditions. PLoS One 2019; 14:e0211101. [PMID: 30689659 PMCID: PMC6349334 DOI: 10.1371/journal.pone.0211101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 01/08/2019] [Indexed: 11/28/2022] Open
Abstract
This descriptive study aimed to compare the magnetic resonance appearance of the distal interphalangeal joint articular cartilage between standing weight-bearing and non-weight-bearing conditions. Ten forefeet of live horses were scanned in a standing low-field magnetic resonance system (0.27 T). After euthanasia for reasons unrelated to the study, the non-weight-bearing isolated feet were scanned in a vertical positioning reproducing limb orientation in live horses. The same acquisition settings as during the weight-bearing examination were used. Thickness and cross-sectional area of the distal interphalangeal articular cartilage and joint space were measured on tridimensional T1-weighted gradient echo high resolution frontal and sagittal images at predetermined landmarks in both conditions and were compared using a linear mixed-effects model. Frontal images were randomized and submitted to 9 blinded readers with 3 different experience levels for identification of weight-bearing versus non-weight-bearing acquisitions based on cartilage appearance. Weight-bearing limbs had significantly thinner distal interphalangeal cartilage (p = 0.0001) than non-weight-bearing limbs. This change was greater in the distal phalanx cartilage than that of the middle phalanx. Blinded readers correctly identified 83% (range 65 to 95%) of the images as weight-bearing or non-weight-bearing acquisitions, with significantly different results observed among the different readers (p < 0.001) and groups (p < 0.001). These results indicate that distal interphalangeal articular cartilage and particularly cartilage of the distal phalanx thins when weight-bearing compared to the non-weight-bearing standing postmortem conditions and suggest that cartilage abnormalities may be more difficult to identify on weight-bearing standing magnetic resonance imaging.
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Affiliation(s)
- Laurence Evrard
- Department of Clinical Sciences of Companion Animals and Equids, Equine Division, Diagnostic Imaging Section, University of Liège, Liège, Belgium
- * E-mail:
| | - Fabrice Audigié
- Centre d’Imagerie et de Recherche sur les Affections Locomotrices Equines (CIRALE), Unité 957 BPLC, Ecole Nationale Vétérinaire d’Alfort, Normandie Equine Vallée, Goustranville, France
| | - Lélia Bertoni
- Centre d’Imagerie et de Recherche sur les Affections Locomotrices Equines (CIRALE), Unité 957 BPLC, Ecole Nationale Vétérinaire d’Alfort, Normandie Equine Vallée, Goustranville, France
| | - Sandrine Jacquet
- Centre d’Imagerie et de Recherche sur les Affections Locomotrices Equines (CIRALE), Unité 957 BPLC, Ecole Nationale Vétérinaire d’Alfort, Normandie Equine Vallée, Goustranville, France
| | - Jean-Marie Denoix
- Centre d’Imagerie et de Recherche sur les Affections Locomotrices Equines (CIRALE), Unité 957 BPLC, Ecole Nationale Vétérinaire d’Alfort, Normandie Equine Vallée, Goustranville, France
| | - Valeria Busoni
- Department of Clinical Sciences of Companion Animals and Equids, Equine Division, Diagnostic Imaging Section, University of Liège, Liège, Belgium
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12
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Sutter EG, Liu B, Utturkar GM, Widmyer MR, Spritzer CE, Cutcliffe HC, Englander ZA, Goode AP, Garrett WE, DeFrate LE. Effects of Anterior Cruciate Ligament Deficiency on Tibiofemoral Cartilage Thickness and Strains in Response to Hopping. Am J Sports Med 2019; 47:96-103. [PMID: 30365903 PMCID: PMC6559720 DOI: 10.1177/0363546518802225] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Changes in knee kinematics after anterior cruciate ligament (ACL) injury may alter loading of the cartilage and thus affect its homeostasis, potentially leading to the development of posttraumatic osteoarthritis. However, there are limited in vivo data to characterize local changes in cartilage thickness and strain in response to dynamic activity among patients with ACL deficiency. PURPOSE/HYPOTHESIS The purpose was to compare in vivo tibiofemoral cartilage thickness and cartilage strain resulting from dynamic activity between ACL-deficient and intact contralateral knees. It was hypothesized that ACL-deficient knees would show localized reductions in cartilage thickness and elevated cartilage strains. STUDY DESIGN Controlled laboratory study. METHODS Magnetic resonance images were obtained before and after single-legged hopping on injured and uninjured knees among 8 patients with unilateral ACL rupture. Three-dimensional models of the bones and articular surfaces were created from the pre- and postactivity scans. The pre- and postactivity models were registered to each other, and cartilage strain (defined as the normalized difference in cartilage thickness pre- and postactivity) was calculated in regions across the tibial plateau, femoral condyles, and femoral cartilage adjacent to the medial intercondylar notch. These measurements were compared between ACL-deficient and intact knees. Differences in cartilage thickness and strain between knees were tested with multiple analysis of variance models with alpha set at P < .05. RESULTS Compressive strain in the intercondylar notch was elevated in the ACL-deficient knee relative to the uninjured knee. Furthermore, cartilage in the intercondylar notch and adjacent medial tibia was significantly thinner before activity in the ACL-deficient knee versus the intact knee. In these 2 regions, thinning was significantly influenced by time since injury, with patients with more chronic ACL deficiency (>1 year since injury) experiencing greater thinning. CONCLUSION Among patients with ACL deficiency, the medial femoral condyle adjacent to the intercondylar notch in the ACL-deficient knee exhibited elevated cartilage strain and loss of cartilage thickness, particularly with longer time from injury. It is hypothesized that these changes may be related to posttraumatic osteoarthritis development. CLINICAL RELEVANCE This study suggests that altered mechanical loading is related to localized cartilage thinning after ACL injury.
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Affiliation(s)
- E. Grant Sutter
- Department of Orthopaedic Surgery, Duke University, Durham,
NC
| | - Betty Liu
- Department of Biomedical Engineering, Duke University,
Durham, NC
| | | | | | | | | | - Zoë A. Englander
- Department of Biomedical Engineering, Duke University,
Durham, NC
| | - Adam P. Goode
- Department of Orthopaedic Surgery, Duke University, Durham,
NC
| | | | - Louis E. DeFrate
- Department of Orthopaedic Surgery, Duke University, Durham,
NC,Department of Biomedical Engineering, Duke University,
Durham, NC,Department of Mechanical Engineering and Materials Science,
Duke University, Durham, NC
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13
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Zevenbergen L, Gsell W, Cai L, Chan DD, Famaey N, Vander Sloten J, Himmelreich U, Neu CP, Jonkers I. Cartilage-on-cartilage contact: effect of compressive loading on tissue deformations and structural integrity of bovine articular cartilage. Osteoarthritis Cartilage 2018; 26:1699-1709. [PMID: 30172835 DOI: 10.1016/j.joca.2018.08.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 08/17/2018] [Accepted: 08/21/2018] [Indexed: 02/09/2023]
Abstract
OBJECTIVE This study aims to characterize the deformations in articular cartilage under compressive loading and link these to changes in the extracellular matrix constituents described by magnetic resonance imaging (MRI) relaxation times in an experimental model mimicking in vivo cartilage-on-cartilage contact. DESIGN Quantitative MRI images, T1, T2 and T1ρ relaxation times, were acquired at 9.4T from bovine femoral osteochondral explants before and immediately after loading. Two-dimensional intra-tissue displacement and strain fields under cyclic compressive loading (350N) were measured using the displacement encoding with stimulated echoes (DENSE) method. Changes in relaxation times in response to loading were evaluated against the deformation fields. RESULTS Deformation fields showed consistent patterns among all specimens, with maximal strains at the articular surface that decrease with tissue depth. Axial and transverse strains were maximal around the center of the contact region, whereas shear strains were minimal around the contact center but increased towards contact edges. A decrease in T2 and T1ρ was observed immediately after loading whereas the opposite was observed for T1. No correlations between cartilage deformation patterns and changes in relaxation times were observed. CONCLUSIONS Displacement encoding combined with relaxometry by MRI can noninvasively monitor the cartilage biomechanical and biochemical properties associated with loading. The deformation fields reveal complex patterns reflecting the depth-dependent mechanical properties, but intra-tissue deformation under compressive loading does not correlate with structural and compositional changes. The compacting effect of cyclic compression on the cartilage tissue was revealed by the change in relaxation time immediately after loading.
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Affiliation(s)
- L Zevenbergen
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.
| | - W Gsell
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.
| | - L Cai
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA.
| | - D D Chan
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA.
| | - N Famaey
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
| | - J Vander Sloten
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
| | - U Himmelreich
- Biomedical MRI, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium.
| | - C P Neu
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA; Department of Mechanical Engineering, University of Colorado Boulder, Colorado, USA.
| | - I Jonkers
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.
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14
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Bernardini G, Leone G, Millucci L, Consumi M, Braconi D, Spiga O, Galderisi S, Marzocchi B, Viti C, Giorgetti G, Lupetti P, Magnani A, Santucci A. Homogentisic acid induces morphological and mechanical aberration of ochronotic cartilage in alkaptonuria. J Cell Physiol 2018; 234:6696-6708. [DOI: 10.1002/jcp.27416] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/21/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Giulia Bernardini
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Gemma Leone
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Lia Millucci
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Marco Consumi
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Daniela Braconi
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Ottavia Spiga
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Silvia Galderisi
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Barbara Marzocchi
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
- UOC Patologia Clinica, Azienda Ospedaliera Universitaria Senese Siena Italy
| | - Cecilia Viti
- Dipartimento di Scienze Fisiche, della Terra e dell'Ambiente Università degli Studi di Siena Siena Italy
| | - Giovanna Giorgetti
- Dipartimento di Scienze Fisiche, della Terra e dell'Ambiente Università degli Studi di Siena Siena Italy
| | - Pietro Lupetti
- Dipartimento di Scienze della Vita Università degli Studi di Siena Siena Italy
| | - Agnese Magnani
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
| | - Annalisa Santucci
- Dipartimento di Biotecnologie, Chimica e Farmacia Università degli Studi di Siena Siena Italy
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15
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Kotelsky A, Woo CW, Delgadillo LF, Richards MS, Buckley MR. An Alternative Method to Characterize the Quasi-Static, Nonlinear Material Properties of Murine Articular Cartilage. J Biomech Eng 2018; 140:2657496. [PMID: 29049670 DOI: 10.1115/1.4038147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Indexed: 11/08/2022]
Abstract
With the onset and progression of osteoarthritis (OA), articular cartilage (AC) mechanical properties are altered. These alterations can serve as an objective measure of tissue degradation. Although the mouse is a common and useful animal model for studying OA, it is extremely challenging to measure the mechanical properties of murine AC due to its small size (thickness < 50 μm). In this study, we developed novel and direct approach to independently quantify two quasi-static mechanical properties of mouse AC: the load-dependent (nonlinear) solid matrix Young's modulus (E) and drained Poisson's ratio (ν). The technique involves confocal microscope-based multiaxial strain mapping of compressed, intact murine AC followed by inverse finite element analysis (iFEA) to determine E and ν. Importantly, this approach yields estimates of E and ν that are independent of the initial guesses used for iterative optimization. As a proof of concept, mechanical properties of AC on the medial femoral condyles of wild-type mice were obtained for both trypsin-treated and control specimens. After proteolytic tissue degradation induced through trypsin treatment, a dramatic decrease in E was observed (compared to controls) at each of the three tested loading conditions. A significant decrease in ν due to trypsin digestion was also detected. These data indicate that the method developed in this study may serve as a valuable tool for comparative studies evaluating factors involved in OA pathogenesis using experimentally induced mouse OA models.
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Affiliation(s)
- Alexander Kotelsky
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
| | - Chandler W Woo
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
| | - Luis F Delgadillo
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
| | - Michael S Richards
- Department of Surgery, School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Avenue, Rm 2.4153, Rochester, NY 14627 e-mail:
| | - Mark R Buckley
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
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16
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Ramirez-Garcia MA, Sloan SR, Nidenberg B, Khalifa YM, Buckley MR. Depth-Dependent Out-of-Plane Young's Modulus of the Human Cornea. Curr Eye Res 2017; 43:595-604. [PMID: 29283675 DOI: 10.1080/02713683.2017.1411951] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Purpose/Aim: Despite their importance in accurate mechanical modeling of the cornea, the depth-dependent material properties of the cornea have only been partially elucidated. In this work, we characterized the depth-dependent out-of-plane Young's modulus of the central and peripheral human cornea with high spatial resolution. MATERIALS AND METHODS Central and peripheral corneal buttons from human donors were subjected to unconfined axial compression followed by stress relaxation for 30 min. Sequences of fluorescent micrographs of full-thickness corneal buttons were acquired throughout the experiment to enable tracking of fluorescently labeled stromal keratocyte nuclei and measurements of depth-dependent infinitesimal strains. The nominal (gross) out-of-plane Young's modulus and drained Poisson's ratio for each whole specimen was computed from the equilibrium stress and overall tissue deformation. The depth-dependent (local) out-of-plane Young's modulus was computed from the equilibrium stress and local tissue strain based on an anisotropic model (transverse isotropy). RESULTS The out-of-plane Young's modulus of the cornea exhibited a strong dependence on in-plane location (peripheral versus central cornea), but not depth. The depth-dependent out-of-plane Young's modulus of central and peripheral specimens ranged between 72.4-102.4 kPa and 38.3-58.9 kPa. The nominal out-of-plane Young's modulus was 87 ± 41.51 kPa and 39.9 ± 15.28 kPa in the central and peripheral cornea, while the drained Poisson's ratio was 0.05 ± 0.02 and 0.07 ± 0.04. CONCLUSIONS The out-of-plane Young's modulus of the cornea is mostly independent of depth, but not in-plane location (i.e. central vs. peripheral). These results may help inform more accurate finite element computer models of the cornea.
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Affiliation(s)
| | - Stephen R Sloan
- a Department of Biomedical Engineering , University of Rochester , Rochester , NY , USA
| | - Bennett Nidenberg
- a Department of Biomedical Engineering , University of Rochester , Rochester , NY , USA
| | - Yousuf M Khalifa
- b Department of Ophthalmology , Emory University , Atlanta , GA , USA
| | - Mark R Buckley
- a Department of Biomedical Engineering , University of Rochester , Rochester , NY , USA
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17
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Associations of three-dimensional T1 rho MR mapping and three-dimensional T2 mapping with macroscopic and histologic grading as a biomarker for early articular degeneration of knee cartilage. Clin Rheumatol 2017; 36:2109-2119. [DOI: 10.1007/s10067-017-3645-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 03/29/2017] [Accepted: 04/18/2017] [Indexed: 12/18/2022]
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18
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Santos S, Maier F, Pierce DM. Anisotropy and inter-condyle heterogeneity of cartilage under large-strain shear. J Biomech 2017; 52:74-82. [DOI: 10.1016/j.jbiomech.2016.12.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 12/11/2016] [Accepted: 12/19/2016] [Indexed: 10/20/2022]
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19
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Henak CR, Ross KA, Bonnevie ED, Fortier LA, Cohen I, Kennedy JG, Bonassar LJ. Human talar and femoral cartilage have distinct mechanical properties near the articular surface. J Biomech 2016; 49:3320-3327. [PMID: 27589932 DOI: 10.1016/j.jbiomech.2016.08.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 08/05/2016] [Accepted: 08/16/2016] [Indexed: 12/16/2022]
Abstract
Talar osteochondral lesions (OCL) frequently occur following injury. Surgical interventions such as femoral condyle allogeneic or autogenic osteochondral transplant (AOT) are often used to treat large talar OCL. Although AOT aims to achieve OCL repair by replacing damaged cartilage with mechanically matched cartilage, the spatially inhomogeneous material behavior of the talar dome and femoral donor sites have not been evaluated or compared. The objective of this study was to characterize the depth-dependent shear properties and friction behavior of human talar and donor-site femoral cartilage. To achieve this objective, depth-dependent shear modulus, depth-dependent energy dissipation and coefficient of friction were measured on osteochondral cores from the femur and talus. Differences between anatomical regions were pronounced near the articular surface, where the femur was softer, dissipated more energy and had a lower coefficient of friction than the talus. Conversely, shear modulus near the osteochondral interface was nearly indistinguishable between anatomical regions. Differences in energy dissipation, shear moduli and friction coefficients have implications for graft survival and host cartilage wear. When the biomechanical variation is combined with known biological variation, these data suggest the use of caution in transplanting cartilage from the femur to the talus. Where alternatives exist in the form of talar allograft, donor-recipient mechanical mismatch can be greatly reduced.
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Affiliation(s)
- Corinne R Henak
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, United States
| | - Keir A Ross
- Hospital for Special Surgery, New York, NY, United States
| | - Edward D Bonnevie
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, United States
| | - Lisa A Fortier
- Department of Clinical Sciences, Cornell University, Ithaca, NY, United States
| | - Itai Cohen
- Department of Physics, Cornell University, Ithaca, NY, United States
| | - John G Kennedy
- Hospital for Special Surgery, New York, NY, United States
| | - Lawrence J Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, United States; Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, United States.
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20
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Lad NK, Liu B, Ganapathy PK, Utturkar GM, Sutter EG, Moorman CT, Garrett WE, Spritzer CE, DeFrate LE. Effect of normal gait on in vivo tibiofemoral cartilage strains. J Biomech 2016; 49:2870-2876. [PMID: 27421206 DOI: 10.1016/j.jbiomech.2016.06.025] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 06/10/2016] [Accepted: 06/23/2016] [Indexed: 11/17/2022]
Abstract
Altered cartilage loading is believed to be associated with osteoarthritis development. However, there are limited data regarding the influence of normal gait, an essential daily loading activity, on cartilage strains. In this study, 8 healthy subjects with no history of knee surgery or injury underwent magnetic resonance imaging of a single knee prior to and following a 20-min walking activity at approximately 1.1m/s. Bone and cartilage surfaces were segmented from these images and compiled into 3-dimensional models of the tibia, femur, and associated cartilage. Thickness changes were measured across a grid of evenly spaced points spanning the models of the articular surfaces. Averaged compartmental strains and local strains were then calculated. Overall compartmental strains after the walking activity were found to be significantly different from zero in all four tibiofemoral compartments, with tibial cartilage strain being significantly larger than femoral cartilage strain. These results provide baseline data regarding the normal tibiofemoral cartilage strain response to gait. Additionally, the technique employed in this study has potential to be used as a "stress test" to understand how factors including age, weight, and injury influence tibiofemoral cartilage strain response, essential information in the development of potential treatment strategies for the prevention of osteoarthritis.
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Affiliation(s)
- Nimit K Lad
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - Betty Liu
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA; Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Pramodh K Ganapathy
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - Gangadhar M Utturkar
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - E Grant Sutter
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - Claude T Moorman
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - William E Garrett
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - Charles E Spritzer
- Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Louis E DeFrate
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA; Department of Biomedical Engineering, Duke University, Durham, NC, USA.
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21
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Olubamiji AD, Izadifar Z, Si JL, Cooper DML, Eames BF, Chen DXB. Modulating mechanical behaviour of 3D-printed cartilage-mimetic PCL scaffolds: influence of molecular weight and pore geometry. Biofabrication 2016; 8:025020. [DOI: 10.1088/1758-5090/8/2/025020] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Camarero-Espinosa S, Rothen-Rutishauser B, Foster EJ, Weder C. Articular cartilage: from formation to tissue engineering. Biomater Sci 2016; 4:734-67. [PMID: 26923076 DOI: 10.1039/c6bm00068a] [Citation(s) in RCA: 180] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Hyaline cartilage is the nonlinear, inhomogeneous, anisotropic, poro-viscoelastic connective tissue that serves as friction-reducing and load-bearing cushion in synovial joints and is vital for mammalian skeletal movements. Due to its avascular nature, low cell density, low proliferative activity and the tendency of chondrocytes to de-differentiate, cartilage cannot regenerate after injury, wear and tear, or degeneration through common diseases such as osteoarthritis. Therefore severe damage usually requires surgical intervention. Current clinical strategies to generate new tissue include debridement, microfracture, autologous chondrocyte transplantation, and mosaicplasty. While articular cartilage was predicted to be one of the first tissues to be successfully engineered, it proved to be challenging to reproduce the complex architecture and biomechanical properties of the native tissue. Despite significant research efforts, only a limited number of studies have evolved up to the clinical trial stage. This review article summarizes the current state of cartilage tissue engineering in the context of relevant biological aspects, such as the formation and growth of hyaline cartilage, its composition, structure and biomechanical properties. Special attention is given to materials development, scaffold designs, fabrication methods, and template-cell interactions, which are of great importance to the structure and functionality of the engineered tissue.
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Affiliation(s)
- Sandra Camarero-Espinosa
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland.
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23
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Amadori S, Torricelli P, Panzavolta S, Parrilli A, Fini M, Bigi A. Highly Porous Gelatin Reinforced 3D Scaffolds for Articular Cartilage Regeneration. Macromol Biosci 2015; 15:941-52. [DOI: 10.1002/mabi.201500014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 03/03/2015] [Indexed: 01/15/2023]
Affiliation(s)
- Sofia Amadori
- Department of Chemistry “G. Ciamician”; University of Bologna; via Selmi 2 40126 Bologna Italy
| | - Paola Torricelli
- Laboratory of Preclinical and Surgical Studies; Research Institute Codivilla Putti - Rizzoli Orthopaedic Institute; via di Barbiano 40126 Bologna Italy
| | - Silvia Panzavolta
- Department of Chemistry “G. Ciamician”; University of Bologna; via Selmi 2 40126 Bologna Italy
| | - Annapaola Parrilli
- Laboratory of Preclinical and Surgical Studies; Research Institute Codivilla Putti - Rizzoli Orthopaedic Institute; via di Barbiano 40126 Bologna Italy
| | - Milena Fini
- Laboratory of Preclinical and Surgical Studies; Research Institute Codivilla Putti - Rizzoli Orthopaedic Institute; via di Barbiano 40126 Bologna Italy
| | - Adriana Bigi
- Department of Chemistry “G. Ciamician”; University of Bologna; via Selmi 2 40126 Bologna Italy
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24
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Sutter EG, Widmyer MR, Utturkar GM, Spritzer CE, Garrett WE, DeFrate LE. In vivo measurement of localized tibiofemoral cartilage strains in response to dynamic activity. Am J Sports Med 2015; 43:370-6. [PMID: 25504809 PMCID: PMC4315145 DOI: 10.1177/0363546514559821] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Altered local mechanical loading may disrupt normal cartilage homeostasis and play a role in the progression of osteoarthritis. Currently, there are limited data quantifying local cartilage strains in response to dynamic activity in normal or injured knees. PURPOSE/HYPOTHESIS To directly measure local tibiofemoral cartilage strains in response to a dynamic hopping activity in normal healthy knees. We hypothesized that local regions of cartilage will exhibit significant compressive strains in response to hopping, while overall compartmental averages may not. STUDY DESIGN Controlled laboratory study. METHODS Both knees of 8 healthy subjects underwent magnetic resonance imaging before and immediately after a dynamic hopping activity. Images were segmented and then used to create 3-dimensional surface models of bone and cartilage. These pre- and postactivity models were then registered using an iterative closest point technique to enable site-specific measurements of cartilage strain (defined as the normalized change in cartilage thickness before and after activity) on the femur and tibia. RESULTS Significant strains were observed in both the medial and lateral tibial cartilage, with each compartment averaging a decrease of 5%. However, these strains varied with location within each compartment, reaching a maximum compressive strain of 8% on the medial plateau and 7% on the lateral plateau. No significant averaged compartmental strains were observed in the medial or lateral femoral cartilage. However, local regions of the medial and lateral femoral cartilage experienced significant compressive strains, reaching maximums of 6% and 3%, respectively. CONCLUSION Local regions of both the femur and tibia experienced significant cartilage strains as a result of dynamic activity. An understanding of changes in cartilage strain distributions may help to elucidate the biomechanical factors contributing to cartilage degeneration after joint injury. CLINICAL RELEVANCE Site-specific measurements of in vivo cartilage strains are important because altered loading is believed to be a factor contributing to the development and progression of osteoarthritis. Specifically, this methodology and data could be used to evaluate the effects of soft tissue injuries (such as ligament or meniscus tears) on cartilage strains in response to dynamic activities of daily living.
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Affiliation(s)
- E Grant Sutter
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Margaret R Widmyer
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
| | - Gangadhar M Utturkar
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Charles E Spritzer
- Department of Radiology, Duke University Medical Center, Durham, North Carolina, USA
| | - William E Garrett
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Louis E DeFrate
- Duke Sports Medicine Center, Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
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25
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Leone G, Volpato MD, Nelli N, Lamponi S, Boanini E, Bigi A, Magnani A. Continuous multilayered composite hydrogel as osteochondral substitute. J Biomed Mater Res A 2014; 103:2521-30. [PMID: 25504681 DOI: 10.1002/jbm.a.35389] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 12/02/2014] [Accepted: 12/08/2014] [Indexed: 01/28/2023]
Abstract
Cartilage is a highly organized avascular soft tissue that assembles from nano-to macro-scale to produce a complex structural network. To mimic cartilage tissue, we developed a stable multilayered composite material, characterized by a tailored gradient of mechanical properties. The optimized procedure implies chemical crosslinking of each layer directly onto the previous one and ensures a drastic reduction of the material discontinuities and brittleness. The multilayered composite was characterized by infrared spectroscopy, differential scanning calorimetry, thermogravimetry, and scanning electron microscopy in order to compare its physico-chemical characteristics with those of cartilage tissue. The rheological behavior of the multilayered composite was similar to that of human cartilage. Finally its cytocompatibility toward chondrocytes and osteoblasts was evaluated.
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Affiliation(s)
- G Leone
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena (INSTM), via Aldo Moro 2, Siena, 53100, Italy
| | - M D Volpato
- Via Fratelli Rosselli, 16-Colle Di Val D'elsa, Siena, Italy
| | - N Nelli
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena (INSTM), via Aldo Moro 2, Siena, 53100, Italy
| | - S Lamponi
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena (INSTM), via Aldo Moro 2, Siena, 53100, Italy
| | - E Boanini
- Department of Chemistry "G. Ciamician,", University of Bologna, via Selmi 2, Bologna, 40126, Italy
| | - A Bigi
- Department of Chemistry "G. Ciamician,", University of Bologna, via Selmi 2, Bologna, 40126, Italy
| | - A Magnani
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena (INSTM), via Aldo Moro 2, Siena, 53100, Italy
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26
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Silverberg JL, Barrett AR, Das M, Petersen PB, Bonassar LJ, Cohen I. Structure-function relations and rigidity percolation in the shear properties of articular cartilage. Biophys J 2014; 107:1721-30. [PMID: 25296326 PMCID: PMC4190603 DOI: 10.1016/j.bpj.2014.08.011] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 08/07/2014] [Accepted: 08/11/2014] [Indexed: 11/18/2022] Open
Abstract
Among mammalian soft tissues, articular cartilage is particularly interesting because it can endure a lifetime of daily mechanical loading despite having minimal regenerative capacity. This remarkable resilience may be due to the depth-dependent mechanical properties, which have been shown to localize strain and energy dissipation. This paradigm proposes that these properties arise from the depth-dependent collagen fiber orientation. Nevertheless, this structure-function relationship has not yet been quantified. Here, we use confocal elastography, quantitative polarized light microscopy, and Fourier-transform infrared imaging to make same-sample measurements of the depth-dependent shear modulus, collagen fiber organization, and extracellular matrix concentration in neonatal bovine articular cartilage. We find weak correlations between the shear modulus |G(∗)| and both the collagen fiber orientation and polarization. We find a much stronger correlation between |G(∗)| and the concentration of collagen fibers. Interestingly, very small changes in collagen volume fraction vc lead to orders-of-magnitude changes in the modulus with |G(∗)| scaling as (vc - v0)(ξ). Such dependencies are observed in the rheology of other biopolymer networks whose structure exhibits rigidity percolation phase transitions. Along these lines, we propose that the collagen network in articular cartilage is near a percolation threshold that gives rise to these large mechanical variations and localization of strain at the tissue's surface.
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Affiliation(s)
| | - Aliyah R Barrett
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York
| | - Moumita Das
- School of Physics & Astronomy, Rochester Institute of Technology, Rochester, New York
| | - Poul B Petersen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York
| | - Lawrence J Bonassar
- Biomedical Engineering, Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York
| | - Itai Cohen
- Physics Department, Cornell University, Ithaca, New York
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27
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Hada S, Kaneko H, Sadatsuki R, Liu L, Futami I, Kinoshita M, Yusup A, Saita Y, Takazawa Y, Ikeda H, Kaneko K, Ishijima M. The degeneration and destruction of femoral articular cartilage shows a greater degree of deterioration than that of the tibial and patellar articular cartilage in early stage knee osteoarthritis: a cross-sectional study. Osteoarthritis Cartilage 2014; 22:1583-9. [PMID: 25278068 DOI: 10.1016/j.joca.2014.07.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 07/20/2014] [Accepted: 07/24/2014] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The aim of the present study was to examine whether the degenerative and morphological changes of articular cartilage in early stage knee osteoarthritis (OA) occurred equally for both femoral- and tibial- or patellar- articular cartilage using magnetic resonance imaging (MRI)-based analyses. DESIGN This cross-sectional study was approved by the ethics committee of our university. Fifty patients with early stage painful knee OA were enrolled. The patients underwent 3.0 T MRI on the affected knee joint. Healthy volunteers who did not show MRI-based OA changes were also recruited as controls (n = 19). The degenerative changes of the articular cartilage were quantified by a T2 mapping analysis, and any structural changes were conducted using Whole Organ Magnetic Resonance Imaging Score (WORMS) technique. RESULTS All patients showed MRI-detected OA morphological changes. The T2 values of femoral condyle (FC) (P < 0.0001) and groove (P = 0.0001) in patients with early stage knee OA were significantly increased in comparison to those in the control, while no significant differences in the T2 values of patellar and tibial plateau (TP) were observed between the patients and the control. The WORMS cartilage and osteophyte scores of the femoral articular cartilage were significantly higher than those in the patellar- (P = 0.001 and P = 0.007, respectively) and tibial- (P = 0.0001 and P < 0.0001, respectively) articular cartilage in the patients with early stage knee OA. CONCLUSIONS The degradation and destruction of the femoral articular cartilage demonstrated a greater degree of deterioration than those of the tibial- and patellar- articular cartilage in patients with early stage knee OA.
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Affiliation(s)
- S Hada
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - H Kaneko
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - R Sadatsuki
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - L Liu
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan; Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - I Futami
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - M Kinoshita
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - A Yusup
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - Y Saita
- Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - Y Takazawa
- Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - H Ikeda
- Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - K Kaneko
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan; Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - M Ishijima
- Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan; Sportology Center, Juntendo University Graduate School of Medicine, Tokyo, Japan.
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28
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Motavalli M, Akkus O, Mansour JM. Depth-dependent shear behavior of bovine articular cartilage: relationship to structure. J Anat 2014; 225:519-26. [PMID: 25146377 DOI: 10.1111/joa.12230] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2014] [Indexed: 11/30/2022] Open
Abstract
The mechanical behavior of bovine articular cartilage in shear was measured and related to its structure through the depth of the tissue. To make these measurements, we designed an apparatus that could apply controlled shear displacement and measure the resulting shear force on cartilage specimens. Shear displacement and shear strain were obtained from confocal images of photobleached lines on fluorescently stained deformed samples. Depth-dependent collagen structure was obtained using compensated polarized light microscopy. Depth-dependent shear behavior and structure of samples from two animals were measured (group A and B). Both animals were 18-24 months old, which is the range in which they are expected reach skeletal maturity. In mature samples (group A), the stiffest region was located beneath the superficial zone, and the most compliant region was found in the radial zone. In contrast, in samples that were in the process of maturing (group B) the most compliant region was located in the superficial zone. Compensated polarized light microscopy suggested that the animal from which the group A samples were obtained was skeletally mature, whereas the animal yielding the group B samples was in the process of maturing. Compensated polarized light microscopy was an important adjunct to the mechanical shear behavior in that it provided a means to reconcile differences in observed shear behavior in mature and immature cartilage. Although samples were harvested from two animals, there were clear differences in structure and shear mechanical behavior. Differences in the depth-dependent shear strain were consistent with previous studies on mature and immature samples and, based on the structural variation between mature and immature articular cartilage, their mechanical behavior differences can be tenable. These results suggest that age, as well as species and anatomic location, need to be considered when reporting mechanical behavior results.
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Affiliation(s)
- Mostafa Motavalli
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH, USA
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29
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Motavalli M, Whitney GA, Dennis JE, Mansour JM. Investigating a continuous shear strain function for depth-dependent properties of native and tissue engineering cartilage using pixel-size data. J Mech Behav Biomed Mater 2013; 28:62-70. [PMID: 23973614 DOI: 10.1016/j.jmbbm.2013.07.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/18/2013] [Accepted: 07/24/2013] [Indexed: 11/26/2022]
Abstract
A previously developed novel imaging technique for determining the depth dependent properties of cartilage in simple shear is implemented. Shear displacement is determined from images of deformed lines photobleached on a sample, and shear strain is obtained from the derivative of the displacement. We investigated the feasibility of an alternative systematic approach to numerical differentiation for computing the shear strain that is based on fitting a continuous function to the shear displacement. Three models for a continuous shear displacement function are evaluated: polynomials, cubic splines, and non-parametric locally weighted scatter plot curves. Four independent approaches are then applied to identify the best-fit model and the accuracy of the first derivative. One approach is based on the Akaiki Information Criteria, and the Bayesian Information Criteria. The second is based on a method developed to smooth and differentiate digitized data from human motion. The third method is based on photobleaching a predefined circular area with a specific radius. Finally, we integrate the shear strain and compare it with the total shear deflection of the sample measured experimentally. Results show that 6th and 7th order polynomials are the best models for the shear displacement and its first derivative. In addition, failure of tissue-engineered cartilage, consistent with previous results, demonstrates the qualitative value of this imaging approach.
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Affiliation(s)
- Mostafa Motavalli
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH, USA.
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30
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Leone G, Bidini A, Lamponi S, Magnani A. States of water, surface and rheological characterisation of a new biohydrogel as articular cartilage substitute. POLYM ADVAN TECHNOL 2013. [DOI: 10.1002/pat.3150] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Gemma Leone
- Department of Biotechnology, Chemistry and Pharmacy; University of Siena; Via Aldo Moro 2 53100 Siena Italy and INSTM
| | | | - Stefania Lamponi
- Department of Biotechnology, Chemistry and Pharmacy; University of Siena; Via Aldo Moro 2 53100 Siena Italy and INSTM
| | - Agnese Magnani
- Department of Biotechnology, Chemistry and Pharmacy; University of Siena; Via Aldo Moro 2 53100 Siena Italy and INSTM
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31
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Silverberg JL, Dillavou S, Bonassar L, Cohen I. Anatomic variation of depth-dependent mechanical properties in neonatal bovine articular cartilage. J Orthop Res 2013; 31:686-91. [PMID: 23280608 DOI: 10.1002/jor.22303] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 12/04/2012] [Indexed: 02/04/2023]
Abstract
Articular cartilage has well known depth-dependent structure and has recently been shown to have similarly non-uniform depth-dependent mechanical properties. Here, we study anatomic variation of the depth-dependent shear modulus and energy dissipation rate in neonatal bovine knees. The regions we specifically focus on are the patellofemoral groove, trochlea, femoral condyle, and tibial plateau. In every sample, we find a highly compliant region within the first 500 µm of tissue measured from the articular surface, where the local shear modulus is reduced by up to two orders of magnitude. Comparing measurements taken from different anatomic sites, we find statistically significant differences localized within the first 50 µm. Histological images reveal these anatomic variations are associated with differences in collagen density and fiber organization.
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Affiliation(s)
- Jesse L Silverberg
- Department of Physics, Cornell University, C10 Clark Hall, Ithaca, NY 14853-2501, USA.
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32
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Furumatsu T, Matsumoto E, Kanazawa T, Fujii M, Lu Z, Kajiki R, Ozaki T. Tensile strain increases expression of CCN2 and COL2A1 by activating TGF-β-Smad2/3 pathway in chondrocytic cells. J Biomech 2013; 46:1508-15. [PMID: 23631855 DOI: 10.1016/j.jbiomech.2013.03.028] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 03/23/2013] [Accepted: 03/30/2013] [Indexed: 10/26/2022]
Abstract
Physiologic mechanical stress stimulates expression of chondrogenic genes, such as multifunctional growth factor CYR61/CTGF/NOV (CCN) 2 and α1(II) collagen (COL2A1), and maintains cartilage homeostasis. In our previous studies, cyclic tensile strain (CTS) induces nuclear translocation of transforming growth factor (TGF)-β receptor-regulated Smad2/3 and the master chondrogenic transcription factor Sry-type HMG box (SOX) 9. However, the precise mechanism of stretch-mediated Smad activation remains unclear in transcriptional regulation of CCN2 and COL2A1. Here we hypothesized that CTS may induce TGF-β1 release and stimulate Smad-dependent chondrogenic gene expression in human chondrocytic SW1353 cells. Uni-axial CTS (0.5Hz, 5% strain) stimulated gene expression of CCN2 and COL2A1 in SW1353 cells, and induced TGF-β1 secretion. CCN2 synthesis and nuclear translocalization of Smad2/3 and SOX9 were stimulated by CTS. In addition, CTS increased the complex formation between phosphorylated Smad2/3 and SOX9. The CCN2 promoter activity was cooperatively enhanced by CTS and Smad3 in luciferase reporter assay. Chromatin immunoprecipitation revealed that CTS increased Smad2/3 interaction with the CCN2 promoter and the COL2A1 enhancer. Our results suggest that CTS epigenetically stimulates CCN2 transcription via TGF-β1 release associated with Smad2/3 activation and enhances COL2A1 expression through the complex formation between SOX9 and Smad2/3.
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Affiliation(s)
- Takayuki Furumatsu
- Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8558, Japan.
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33
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Dowling EP, Ronan W, McGarry JP. Computational investigation of in situ chondrocyte deformation and actin cytoskeleton remodelling under physiological loading. Acta Biomater 2013; 9:5943-55. [PMID: 23271042 DOI: 10.1016/j.actbio.2012.12.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 12/14/2012] [Accepted: 12/17/2012] [Indexed: 12/22/2022]
Abstract
Previous experimental studies have determined local strain fields for both healthy and degenerate cartilage tissue during mechanical loading. However, the biomechanical response of chondrocytes in situ, in particular the response of the actin cytoskeleton to physiological loading conditions, is poorly understood. In the current study a three-dimensional (3-D) representative volume element (RVE) for cartilage tissue is created, comprising a chondrocyte surrounded by a pericellular matrix and embedded in an extracellular matrix. A 3-D active modelling framework incorporating actin cytoskeleton remodelling and contractility is implemented to predict the biomechanical behaviour of chondrocytes. Physiological and abnormal strain fields, based on the experimental study of Wong and Sah (J. Orthop. Res. 2010; 28: 1554-1561), are applied to the RVE. Simulations demonstrate that the presence of a focal defect significantly affects cellular deformation, increases the stress experienced by the nucleus, and alters the distribution of the actin cytoskeleton. It is demonstrated that during dynamic loading cyclic tension reduction in the cytoplasm causes continuous dissociation of the actin cytoskeleton. In contrast, during static loading significant changes in cytoplasm tension are not predicted and hence the rate of dissociation of the actin cytoskeleton is reduced. It is demonstrated that chondrocyte behaviour is affected by the stiffness of the pericellular matrix, and also by the anisotropy of the extracellular matrix. The findings of the current study are of particular importance in understanding the biomechanics underlying experimental observations such as actin cytoskeleton dissociation during the dynamic loading of chondrocytes.
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Affiliation(s)
- Enda P Dowling
- Mechanical and Biomedical Engineering, National University of Ireland-Galway, Galway, Ireland
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34
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Diurnal variations in articular cartilage thickness and strain in the human knee. J Biomech 2012; 46:541-7. [PMID: 23102493 DOI: 10.1016/j.jbiomech.2012.09.013] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 09/26/2012] [Accepted: 09/28/2012] [Indexed: 11/21/2022]
Abstract
Due to the biphasic viscoelastic nature of cartilage, joint loading may result in deformations that require times on the order of hours to fully recover. Thus, cartilaginous tissues may exhibit cumulative strain over the course of each day. The goal of this study was to assess the magnitude and spatial distribution of strain in the articular cartilage of the knee with daily activity. Magnetic resonance (MR) images of 10 asymptomatic subjects (six males and four females) with mean age of 29 years were obtained at 8:00 AM and 4:00 PM on the same day using a 3T magnet. These images were used to create 3D models of the femur, tibia, and patella from which cartilage thickness distributions were quantified. Cartilage thickness generally decreased from AM to PM in all areas except the patellofemoral groove and was associated with significant compressive strains in the medial condyle and tibial plateau. From AM to PM, cartilage of the medial tibial plateau exhibited a compressive strain of -5.1±1.0% (mean±SEM) averaged over all locations, while strains in the lateral plateau were slightly lower (-3.1±0.6%). Femoral cartilage showed an average strain of -1.9±0.6%. The findings of this study show that human knee cartilage undergoes diurnal changes in strain that vary with site in the joint. Since abnormal joint loading can be detrimental to cartilage homeostasis, these data provide a baseline for future studies investigating the effects of altered biomechanics on diurnal cartilage strains and cartilage physiology.
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35
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McLeod MA, Wilusz RE, Guilak F. Depth-dependent anisotropy of the micromechanical properties of the extracellular and pericellular matrices of articular cartilage evaluated via atomic force microscopy. J Biomech 2012; 46:586-92. [PMID: 23062866 DOI: 10.1016/j.jbiomech.2012.09.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 08/21/2012] [Accepted: 09/07/2012] [Indexed: 01/30/2023]
Abstract
The extracellular matrix (ECM) of articular cartilage is structurally and mechanically inhomogeneous and anisotropic, exhibiting variations in composition, collagen fiber architecture, and pericellular matrix (PCM) morphology among the different zones (superficial, middle, and deep). Joint loading exposes chondrocytes to a complex biomechanical environment, as the microscale mechanical environment of the chondrocyte depends on the relative properties of its PCM and local ECM. ECM anisotropy and chondrocyte deformation are influenced by the split-line direction, the preferred collagen fiber orientation parallel to the articular surface. While previous studies have demonstrated that cartilage macroscale properties vary with depth and the direction of loading relative to the split-line direction, the potential anisotropic behavior of the ECM and PCM at the microscale has yet to be examined. The goal of this study was to characterize the depth and directional dependence of the microscale biomechanical properties of porcine cartilage ECM and PCM in situ. Cartilage was cryosectioned to generate samples oriented parallel and perpendicular to the split-line direction and normal to the articular surface. Atomic force microscopy (AFM)-based stiffness mapping was utilized to measure ECM and PCM microscale elastic properties in all three directions within each zone. Distinct anisotropy in ECM elastic moduli was observed in the superficial and deep zones, while the middle zone exhibited subtle anisotropy. PCM elastic moduli exhibited zonal uniformity with depth and directional dependence when pooled across the zones. These findings provide new evidence for mechanical inhomogeneity and anisotropy at the microscale in articular cartilage.
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Affiliation(s)
- Morgan A McLeod
- Departments of Orthopaedic Surgery and Biomedical Engineering, Duke University, Durham, NC, USA
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36
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Dowling EP, Ronan W, Ofek G, Deshpande VS, McMeeking RM, Athanasiou KA, McGarry JP. The effect of remodelling and contractility of the actin cytoskeleton on the shear resistance of single cells: a computational and experimental investigation. J R Soc Interface 2012; 9:3469-79. [PMID: 22809850 DOI: 10.1098/rsif.2012.0428] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The biomechanisms that govern the response of chondrocytes to mechanical stimuli are poorly understood. In this study, a series of in vitro tests are performed, in which single chondrocytes are subjected to shear deformation by a horizontally moving probe. Dramatically different probe force-indentation curves are obtained for untreated cells and for cells in which the actin cytoskeleton has been disrupted. Untreated cells exhibit a rapid increase in force upon probe contact followed by yielding behaviour. Cells in which the contractile actin cytoskeleton was removed exhibit a linear force-indentation response. In order to investigate the mechanisms underlying this behaviour, a three-dimensional active modelling framework incorporating stress fibre (SF) remodelling and contractility is used to simulate the in vitro tests. Simulations reveal that the characteristic force-indentation curve observed for untreated chondrocytes occurs as a result of two factors: (i) yielding of SFs due to stretching of the cytoplasm near the probe and (ii) dissociation of SFs due to reduced cytoplasm tension at the front of the cell. In contrast, a passive hyperelastic model predicts a linear force-indentation curve similar to that observed for cells in which the actin cytoskeleton has been disrupted. This combined modelling-experimental study offers a novel insight into the role of the active contractility and remodelling of the actin cytoskeleton in the response of chondrocytes to mechanical loading.
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Affiliation(s)
- Enda P Dowling
- Mechanical and Biomedical Engineering, National University of Ireland, University Road, Galway, Republic of Ireland
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37
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O’Connell GD, Lima EG, Bian L, Chahine NO, Albro MB, Cook JL, Ateshian GA, Hung CT. Toward engineering a biological joint replacement. J Knee Surg 2012; 25:187-96. [PMID: 23057137 PMCID: PMC3700804 DOI: 10.1055/s-0032-1319783] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Osteoarthritis is a major cause of disability and pain for patients in the United States. Treatments for this degenerative disease represent a significant challenge considering the poor regenerative capacity of adult articular cartilage. Tissue-engineering techniques have advanced over the last two decades such that cartilage-like tissue can be cultivated in the laboratory for implantation. Even so, major challenges remain for creating fully functional tissue. This review article overviews some of these challenges, including overcoming limitations in nutrient supply to cartilage, improving in vitro collagen production, improving integration of engineered cartilage with native tissue, and exploring the potential for engineering full articular surface replacements.
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Affiliation(s)
| | - Eric G. Lima
- Department of Mechanical Engineering, Cooper Union, New York
| | - Liming Bian
- Department of Mechanical & Automation Engineering, Biomedical Engineering Programme, The Chinese University of Hong Kong, Hong Kong
| | - Nadeen O. Chahine
- Department of Bioengineering, The Feinstein Institute for Medical Research, Manhasset, New York
| | - Michael B. Albro
- Department of Mechanical Engineering, Columbia University, New York
| | - James L. Cook
- Comparative Orthopaedic Laboratory, University of Missouri, Columbia, Missouri
| | | | - Clark T. Hung
- Department of Biomedical Engineering, Columbia University, New York
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Halloran JP, Sibole S, van Donkelaar CC, van Turnhout MC, Oomens CWJ, Weiss JA, Guilak F, Erdemir A. Multiscale mechanics of articular cartilage: potentials and challenges of coupling musculoskeletal, joint, and microscale computational models. Ann Biomed Eng 2012; 40:2456-74. [PMID: 22648577 DOI: 10.1007/s10439-012-0598-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 05/16/2012] [Indexed: 11/27/2022]
Abstract
Articular cartilage experiences significant mechanical loads during daily activities. Healthy cartilage provides the capacity for load bearing and regulates the mechanobiological processes for tissue development, maintenance, and repair. Experimental studies at multiple scales have provided a fundamental understanding of macroscopic mechanical function, evaluation of the micromechanical environment of chondrocytes, and the foundations for mechanobiological response. In addition, computational models of cartilage have offered a concise description of experimental data at many spatial levels under healthy and diseased conditions, and have served to generate hypotheses for the mechanical and biological function. Further, modeling and simulation provides a platform for predictive risk assessment, management of dysfunction, as well as a means to relate multiple spatial scales. Simulation-based investigation of cartilage comes with many challenges including both the computational burden and often insufficient availability of data for model development and validation. This review outlines recent modeling and simulation approaches to understand cartilage function from a mechanical systems perspective, and illustrates pathways to associate mechanics with biological function. Computational representations at single scales are provided from the body down to the microstructure, along with attempts to explore multiscale mechanisms of load sharing that dictate the mechanical environment of the cartilage and chondrocytes.
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Affiliation(s)
- J P Halloran
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
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Winalski CS, Rajiah P. The evolution of articular cartilage imaging and its impact on clinical practice. Skeletal Radiol 2011; 40:1197-222. [PMID: 21847750 DOI: 10.1007/s00256-011-1226-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 06/27/2011] [Indexed: 02/02/2023]
Abstract
Over the past four decades, articular cartilage imaging has developed rapidly. Imaging now plays a critical role not only in clinical practice and therapeutic decisions but also in the basic research probing our understanding of cartilage physiology and biomechanics.
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Affiliation(s)
- Carl S Winalski
- Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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Wong BL, Kim SHC, Antonacci JM, McIlwraith CW, Sah RL. Cartilage shear dynamics during tibio-femoral articulation: effect of acute joint injury and tribosupplementation on synovial fluid lubrication. Osteoarthritis Cartilage 2010; 18:464-71. [PMID: 20004636 PMCID: PMC2905237 DOI: 10.1016/j.joca.2009.11.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Revised: 11/06/2009] [Accepted: 11/13/2009] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the effects of acute injury and tribosupplementation by hyaluronan (HA) on synovial fluid (SF) modulation of cartilage shear during tibio-femoral articulation. METHODS Human osteochondral blocks from the lateral femoral condyle (LFC) and tibial plateau (LTP) were apposed, compressed 13%, and subjected to sliding under video microscopy. Tests were conducted with equine SF from normal joints (NL-SF), SF from acutely injured joints (AI-SF), and AI-SF to which HA was added (AI-SF+HA). Local and overall shear strain (E(xz)) and the lateral displacement (Deltax) at which E(xz) reached 50% of peak values (Deltax(1/2)) were determined. RESULTS During articulation, LFC and LTP cartilage E(xz) increased with Deltax and peaked when surfaces slid, with peak E(xz) being maintained during sliding. With AI-SF as lubricant, surface and overall Deltax(1/2) were approximately 40% and approximately 20% higher, respectively, than values with NL-SF and AI-SF+HA as lubricant. Also, peak E(xz) was markedly higher with AI-SF as lubricant than with NL-SF as lubricant, both near the surface (approximately 80%) and overall (50-200%). Following HA supplementation to AI-SF, E(xz) was reduced from values with AI-SF alone by 30-50% near the surface and 20-30% overall. Magnitudes of surface and overall E(xz) were markedly (approximately 50 to 80%) higher in LTP cartilage than LFC cartilage for all lubricants. CONCLUSION Acute injury impairs SF function, elevating cartilage E(xz) markedly during tibio-femoral articulation; such elevated E(xz) may contribute to post-injury associated cartilage degeneration. Since HA partially restores the function of AI-SF, as indicated by E(xz), tribosupplements may be beneficial in modulating normal cartilage homeostasis.
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Affiliation(s)
- Benjamin L. Wong
- Department of Bioengineering, University of California-San Diego, La Jolla, CA
| | | | | | - C. Wayne McIlwraith
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO
| | - Robert L. Sah
- Department of Bioengineering, University of California-San Diego, La Jolla, CA
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