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Yu C, Chen R, Chen J, Wang T, Wang Y, Zhang X, Wang Y, Wu T, Yu T. Enhancing tendon-bone integration and healing with advanced multi-layer nanofiber-reinforced 3D scaffolds for acellular tendon complexes. Mater Today Bio 2024; 26:101099. [PMID: 38840797 PMCID: PMC11152696 DOI: 10.1016/j.mtbio.2024.101099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 05/20/2024] [Accepted: 05/21/2024] [Indexed: 06/07/2024] Open
Abstract
Advancements in tissue engineering are crucial for successfully healing tendon-bone connections, especially in situations like anterior cruciate ligament (ACL) restoration. This study presents a new and innovative three-dimensional scaffold, reinforced with nanofibers, that is specifically intended for acellular tendon complexes. The scaffold consists of a distinct layered arrangement comprising an acellular tendon core, a middle layer of polyurethane/type I collagen (PU/Col I) yarn, and an outside layer of poly (L-lactic acid)/bioactive glass (PLLA/BG) nanofiber membrane. Every layer is designed to fulfill specific yet harmonious purposes. The acellular tendon core is a solid structural base and a favorable environment for tendon cell functions, resulting in considerable tensile strength. The central PU/Col I yarn layer is vital in promoting the tendinogenic differentiation of stem cells derived from tendons and increasing the expression of critical tendinogenic factors. The external PLLA/BG nanofiber membrane fosters the process of bone marrow mesenchymal stem cells differentiating into bone cells and enhances the expression of markers associated with bone formation. Our scaffold's biocompatibility and multi-functional design were confirmed through extensive in vivo evaluations, such as histological staining and biomechanical analyses. These assessments combined showed notable enhancements in ACL repair and healing. This study emphasizes the promise of multi-layered nanofiber scaffolds in orthopedic tissue engineering and also introduces new possibilities for the creation of improved materials for regenerating the tendon-bone interface.
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Affiliation(s)
- Chenghao Yu
- Department of Orthopedic Surgery, Qingdao Municipal Hospital, University of Health and Rehabilitation Sciences, Qingdao, Shandong, 266071, China
- The Affiliated Hospital of Qingdao University, Qingdao Medical College, Qingdao University, Qingdao, Shandong, 266000, China
- Shandong Key Laboratory of Medical and Health Textile Materials, College of Textile & Clothing, Qingdao University, Qingdao, Shandong, 266071, China
- Institute of Neuroregeneration & Neurorehabilitation, Department of Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, 266071, China
| | - Renjie Chen
- Beijing Jishuitan Hospital National Center for Orthopaedics, Beijing, 102208, China
| | - Jinli Chen
- The Affiliated Hospital of Qingdao University, Qingdao Medical College, Qingdao University, Qingdao, Shandong, 266000, China
| | - Tianrui Wang
- The Affiliated Hospital of Qingdao University, Qingdao Medical College, Qingdao University, Qingdao, Shandong, 266000, China
| | - Yawen Wang
- The Affiliated Hospital of Qingdao University, Qingdao Medical College, Qingdao University, Qingdao, Shandong, 266000, China
- Shandong Key Laboratory of Medical and Health Textile Materials, College of Textile & Clothing, Qingdao University, Qingdao, Shandong, 266071, China
- Institute of Neuroregeneration & Neurorehabilitation, Department of Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, 266071, China
| | - Xiaopei Zhang
- The Affiliated Hospital of Qingdao University, Qingdao Medical College, Qingdao University, Qingdao, Shandong, 266000, China
- Shandong Key Laboratory of Medical and Health Textile Materials, College of Textile & Clothing, Qingdao University, Qingdao, Shandong, 266071, China
- Institute of Neuroregeneration & Neurorehabilitation, Department of Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, 266071, China
| | - Yuanfei Wang
- Qingdao Stomatological Hospital Affiliated to Qingdao University, Qingdao, 266001, China
| | - Tong Wu
- The Affiliated Hospital of Qingdao University, Qingdao Medical College, Qingdao University, Qingdao, Shandong, 266000, China
- Shandong Key Laboratory of Medical and Health Textile Materials, College of Textile & Clothing, Qingdao University, Qingdao, Shandong, 266071, China
- Institute of Neuroregeneration & Neurorehabilitation, Department of Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, 266071, China
| | - Tengbo Yu
- Department of Orthopedic Surgery, Qingdao Municipal Hospital, University of Health and Rehabilitation Sciences, Qingdao, Shandong, 266071, China
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Liu N, Jiang J, Liu T, Chen H, Jiang N. Compositional, Structural, and Biomechanical Properties of Three Different Soft Tissue-Hard Tissue Insertions: A Comparative Review. ACS Biomater Sci Eng 2024; 10:2659-2679. [PMID: 38697939 DOI: 10.1021/acsbiomaterials.3c01796] [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] [Indexed: 05/05/2024]
Abstract
Connective tissue attaches to bone across an insertion with spatial gradients in components, microstructure, and biomechanics. Due to regional stress concentrations between two mechanically dissimilar materials, the insertion is vulnerable to mechanical damage during joint movements and difficult to repair completely, which remains a significant clinical challenge. Despite interface stress concentrations, the native insertion physiologically functions as the effective load-transfer device between soft tissue and bone. This review summarizes tendon, ligament, and meniscus insertions cross-sectionally, which is novel in this field. Herein, the similarities and differences between the three kinds of insertions in terms of components, microstructure, and biomechanics are compared in great detail. This review begins with describing the basic components existing in the four zones (original soft tissue, uncalcified fibrocartilage, calcified fibrocartilage, and bone) of each kind of insertion, respectively. It then discusses the microstructure constructed from collagen, glycosaminoglycans (GAGs), minerals and others, which provides key support for the biomechanical properties and affects its physiological functions. Finally, the review continues by describing variations in mechanical properties at the millimeter, micrometer, and nanometer scale, which minimize stress concentrations and control stretch at the insertion. In summary, investigating the contrasts between the three has enlightening significance for future directions of repair strategies of insertion diseases and for bioinspired approaches to effective soft-hard interfaces and other tough and robust materials in medicine and engineering.
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Affiliation(s)
- Nian Liu
- West China School of Stomatology, Sichuan University, Chengdu, Sichuan 610207, China
| | - Jialing Jiang
- West China School of Stomatology, Sichuan University, Chengdu, Sichuan 610207, China
| | - Tiancheng Liu
- West China Hospital, Sichuan University, Chengdu, Sichuan 610207, China
| | - Haozhe Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, China
| | - Nan Jiang
- State Key Laboratory of Oral Diseases, & National Clinical Research Center for Oral Disease, & West China Hospital of Stomatology and the Research Center for Nano Biomaterials, Analytical & Testing Center, Sichuan University, Chengdu, Sichuan 610041, China
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3
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Bianchi E, Ruggeri M, Del Favero E, Pisano R, Artusio F, Ricci C, Vigani B, Ferraretto A, Boselli C, Icaro Cornaglia A, Rossi S, Sandri G. Chondroitin sulfate and caseinophosphopeptides doped polyurethane-based highly porous 3D scaffolds for tendon-to-bone regeneration. Int J Pharm 2024; 652:123822. [PMID: 38242257 DOI: 10.1016/j.ijpharm.2024.123822] [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: 11/14/2023] [Revised: 01/16/2024] [Accepted: 01/16/2024] [Indexed: 01/21/2024]
Abstract
Tendon disorders are common injuries, which can be greatly debilitating as they are often accompanied by great pain and inflammation. Moreover, several problems are also related to the laceration of the tendon-to-bone interface (TBI), a specific region subjected to great mechanical stresses. The techniques used nowadays for the treatment of tendon and TBI injuries often involve surgery. However, one critical aspect of this procedure involves the elevated risk of fail due to the tissues weakening and the postoperative alterations of the normal joint mechanics. Synthetic polymers, such as thermoplastic polyurethane, are of special interest in the tissue engineering field as they allow the production of scaffolds with tunable elastic and mechanical properties, that could guarantee an effective support during the new tissue formation. Based on these premises, the aim of this work was the design and the development of highly porous 3D scaffolds based on thermoplastic polyurethane, and doped with chondroitin sulfate and caseinophosphopeptides, able to mimic the structural, biomechanical, and biochemical functions of the TBI. The obtained scaffolds were characterized by a homogeneous microporous structure, and by a porosity optimal for cell nutrition and migration. They were also characterized by remarkable mechanical properties, reaching values comparable to the ones of the native tendons. The scaffolds promoted the tenocyte adhesion and proliferation when caseinophosphopetides and chondroitin sulfate are present in the 3D structure. In particular, caseinophosphopeptides' optimal concentration for cell proliferation resulted 2.4 mg/mL. Finally, the systems evaluation in vivo demonstrated the scaffolds' safety, since they did not cause any inflammatory effect nor foreign body response, representing interesting platforms for the regeneration of injured TBI.
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Affiliation(s)
- Eleonora Bianchi
- Department of Drug Sciences, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Marco Ruggeri
- Department of Drug Sciences, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Elena Del Favero
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milano, Italy
| | - Roberto Pisano
- Department of Applied Science and Technology (DISAT), Polytechnic of Torino, Torino, Italy
| | - Fiora Artusio
- Department of Applied Science and Technology (DISAT), Polytechnic of Torino, Torino, Italy
| | - Caterina Ricci
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milano, Italy
| | - Barbara Vigani
- Department of Drug Sciences, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Anita Ferraretto
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Mangiagalli 31, Milan, Italy; Laboratory of Experimental Biochemistry & Molecular Biology, IRCCS Istituto Galeazzi-Sant'Ambrogio, Via Cristina Belgioioso 173, 20157 Milan, Italy
| | - Cinzia Boselli
- Department of Drug Sciences, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Antonia Icaro Cornaglia
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, via Forlanini 2, 27100 Pavia, Italy
| | - Silvia Rossi
- Department of Drug Sciences, University of Pavia, via Taramelli 12, 27100 Pavia, Italy
| | - Giuseppina Sandri
- Department of Drug Sciences, University of Pavia, via Taramelli 12, 27100 Pavia, Italy.
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Wang C, Zhang X, Wang DM, Yung PSH, Tuan RS, Ker DFE. Optimized design of an enthesis-mimicking suture anchor-tendon hybrid graft for mechanically robust bone-tendon repair. Acta Biomater 2024; 176:277-292. [PMID: 38244656 DOI: 10.1016/j.actbio.2024.01.011] [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: 09/18/2023] [Revised: 11/22/2023] [Accepted: 01/09/2024] [Indexed: 01/22/2024]
Abstract
Repair of functionally graded biological interfaces requires joining dissimilar materials such as hard bone to soft tendon/ligament, with re-injuries/re-tears expected to be minimized by incorporating biomimicking, stress-reducing features within grafts. At bone-tendon interfaces (entheses), stress can be reduced via angled insertion, geometric flaring, mechanical gradation, and interdigitation of tissues. Here, we incorporated enthesis attributes into 3D in silico and physical models of a unique suture anchor-tendon hybrid graft (SATHG) and investigated their effects on stress reduction via finite element analyses (FEA) studies. Over 20 different simulations altering SATHG angulation, flaring, mechanical gradation, and interdigitation identified an optimal design, which included 90° angulation, 25° flaring, and a compliant (ascending then descending) mechanical gradient in SATHG's bone-to-tendon-like transitional region. This design reduced peak stress concentration factor (SCF) by 43.6 % relative to an ascending-only mechanical gradient typically used in hard-to-soft tissue engineering. To verify FEA results, SATHG models were fabricated using a photocrosslinkable bone-tendon-like polyurethane (QHM polymer) for ex vivo tensile assessment. Tensile testing showed that ultimate load (132.9 N), displacement-at-failure (1.78 mm), stiffness (135.4 N/mm), and total work-to-failure (422.1 × 10-3 J) were highest in the optimized design. Furthermore, to assess envisioned usage, SATHG pull-out testing and 6-week in vivo implantation into large, 0.5-cm segmental supraspinatus tendon defects was performed. SATHG pull-out testing showed secure bone attachment while histological assessment such as hematoxylin and eosin (H&E) together with Safranin-O staining showed biocompatibility including enthesis regeneration. This work demonstrates that engineering biomaterials with FEA-optimized, enthesis-like attributes shows potential for enhancing hard-to-soft tissue repair. STATEMENT OF SIGNIFICANCE: Successful repair of hard-to-soft tissue injuries is challenging due to high stress concentrations within bone-tendon/ligament grafts that mechanically compromise repair strength. While stress-reducing gradient biomaterials have been reported, little-to-no attention has focused on other bone-tendon/ligament interface (enthesis) features. To this end, a unique bone-tendon graft (SATHG) was developed by combining two common orthopaedic devices along with biomimetic incorporation of four enthesis-like features to reduce stress and encourage widespread clinician adoption. Notably, utilizing designs based on natural stress dissipation principles such as anchor insertion angle, geometric flaring, and mechanical gradation reduced stress by 43.6 % in silico, which was confirmed ex vivo, while in vivo studies showed SATHG's ability to support native enthesis regeneration. Thus, SATHG shows promise for hard-to-soft tissue repairs.
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Affiliation(s)
- Chenyang Wang
- Institute for Tissue Engineering and Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; School of Biomedical Sciences, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR
| | - Xu Zhang
- Institute for Tissue Engineering and Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; School of Biomedical Sciences, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; Center for Neuromusculoskeletal Restorative Medicine, InnoHK, Hong Kong Science Park, Hong Kong SAR
| | - Dan Michelle Wang
- Institute for Tissue Engineering and Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; School of Biomedical Sciences, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; Ministry of Education Key Laboratory for Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; Center for Neuromusculoskeletal Restorative Medicine, InnoHK, Hong Kong Science Park, Hong Kong SAR; Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Lui Che Woo Clinical Science Building, Prince of Wales Hospital, Hong Kong SAR
| | - Patrick S H Yung
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Lui Che Woo Clinical Science Building, Prince of Wales Hospital, Hong Kong SAR; Center for Neuromusculoskeletal Restorative Medicine, InnoHK, Hong Kong Science Park, Hong Kong SAR; Institute for Tissue Engineering and Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR
| | - Rocky S Tuan
- Institute for Tissue Engineering and Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; School of Biomedical Sciences, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; Center for Neuromusculoskeletal Restorative Medicine, InnoHK, Hong Kong Science Park, Hong Kong SAR; Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Lui Che Woo Clinical Science Building, Prince of Wales Hospital, Hong Kong SAR
| | - Dai Fei Elmer Ker
- Institute for Tissue Engineering and Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; School of Biomedical Sciences, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; Ministry of Education Key Laboratory for Regenerative Medicine, Lo Kwee-Seong Biomedical Sciences Building, Area 39, The Chinese University of Hong Kong, Hong Kong SAR; Center for Neuromusculoskeletal Restorative Medicine, InnoHK, Hong Kong Science Park, Hong Kong SAR; Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Lui Che Woo Clinical Science Building, Prince of Wales Hospital, Hong Kong SAR.
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5
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Nag S, De Bruyker I, Nelson A, Moody M, Fais M, Deymier AC. Acidosis induces significant changes to the murine supraspinatus enthesis organic matrix. Connect Tissue Res 2024; 65:41-52. [PMID: 37962089 DOI: 10.1080/03008207.2023.2275044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 10/13/2023] [Indexed: 11/15/2023]
Abstract
Rotator cuff pathology is a common musculoskeletal condition that disproportionately affects older adults, as well as patients with diabetes mellitus and chronic kidney disease. It is known that increased age and kidney dysfunction have been correlated to acidotic states, which may be related to the increased incidence of rotator cuff injury. In order to investigate the potential relationship between acidosis and rotator cuff composition and mechanics, this study utilizes a 14-day murine model of metabolic acidosis and examines the effects on the supraspinatus tendon-humeral head attachment complex. The elastic matrix in the enthesis exhibited significant changes beginning at day 3 of acidosis exposure. At day 3 and day 7 timepoints, there was a decrease in collagen content seen in both mineralized and unmineralized tissue as well as a decrease in mineral:matrix ratio. There is also evidence of both mineral dissolution and reprecipitation as buffering ions continually promote pH homeostasis. Mechanical properties of the tendon-to-bone attachment were studied; however, no significant changes were elicited in this 14-day model of acidosis. These findings suggest that acidosis can result in significant changes in enthesis composition over the course of 14 days; however, enthesis mechanics may be more structurally mediated rather than affected by compositional changes.
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Affiliation(s)
- Saparja Nag
- School of Medicine, University of Connecticut, Farmington, CT, USA
| | | | - Ashley Nelson
- Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - Mikayla Moody
- Biomedical Engineering, University of Connecticut Health Center, Farmington, CT, USA
| | - Marla Fais
- Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - Alix C Deymier
- Biomedical Engineering, University of Connecticut, Storrs, CT, USA
- Biomedical Engineering, University of Connecticut Health Center, Farmington, CT, USA
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Tits A, Blouin S, Rummler M, Kaux JF, Drion P, van Lenthe GH, Weinkamer R, Hartmann MA, Ruffoni D. Structural and functional heterogeneity of mineralized fibrocartilage at the Achilles tendon-bone insertion. Acta Biomater 2023; 166:409-418. [PMID: 37088163 DOI: 10.1016/j.actbio.2023.04.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 03/30/2023] [Accepted: 04/13/2023] [Indexed: 04/25/2023]
Abstract
A demanding task of the musculoskeletal system is the attachment of tendon to bone at entheses. This region often presents a thin layer of fibrocartilage (FC), mineralized close to the bone and unmineralized close to the tendon. Mineralized FC deserves increased attention, owing to its crucial anchoring task and involvement in enthesis pathologies. Here, we analyzed mineralized FC and subchondral bone at the Achilles tendon-bone insertion of rats. This location features enthesis FC anchoring tendon to bone and sustaining tensile loads, and periosteal FC facilitating bone-tendon sliding with accompanying compressive and shear forces. Using a correlative multimodal investigation, we evaluated potential specificities in mineral content, fiber organization and mechanical properties of enthesis and periosteal FC. Both tissues had a lower degree of mineralization than subchondral bone, yet used the available mineral very efficiently: for the same local mineral content, they had higher stiffness and hardness than bone. We found that enthesis FC was characterized by highly aligned mineralized collagen fibers even far away from the attachment region, whereas periosteal FC had a rich variety of fiber arrangements. Except for an initial steep spatial gradient between unmineralized and mineralized FC, local mechanical properties were surprisingly uniform inside enthesis FC while a modulation in stiffness, independent from mineral content, was observed in periosteal FC. We interpreted these different structure-property relationships as a demonstration of the high versatility of FC, providing high strength at the insertion (to resist tensile loading) and a gradual compliance at the periosteal surface (to resist contact stresses). STATEMENT OF SIGNIFICANCE: Mineralized fibrocartilage (FC) at entheses facilitates the integration of tendon in bone, two strongly dissimilar tissues. We focus on the structure-function relationships of two types of mineralized FC, enthesis and periosteal, which have clearly distinct mechanical demands. By investigating them with multiple high-resolution methods in a correlative manner, we demonstrate differences in fiber architecture and mechanical properties between the two tissues, indicative of their mechanical roles. Our results are relevant both from a medical viewpoint, targeting a clinically relevant location, as well as from a material science perspective, identifying FC as high-performance versatile composite.
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Affiliation(s)
- Alexandra Tits
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Liège, Belgium.
| | - Stéphane Blouin
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Maximilian Rummler
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Jean-François Kaux
- Department of Physical Medicine and Sports Traumatology, University of Liège and University Hospital of Liège, Liège, Belgium
| | - Pierre Drion
- Experimental Surgery unit, GIGA & Credec, University of Liège, Liège, Belgium
| | | | - Richard Weinkamer
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Markus A Hartmann
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Davide Ruffoni
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Liège, Belgium.
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Ji W, Han F, Feng X, Shi L, Ma H, Lu Y, Tao R. Cocktail-like gradient gelatin/hyaluronic acid bioimplant for enhancing tendon-bone healing in fatty-infiltrated rotator cuff injury models. Int J Biol Macromol 2023:125421. [PMID: 37330074 DOI: 10.1016/j.ijbiomac.2023.125421] [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: 01/18/2023] [Revised: 05/28/2023] [Accepted: 06/14/2023] [Indexed: 06/19/2023]
Abstract
The regeneration of enthesis tissue (native tendon-bone interface) at the post-surgically repaired rotator cuff remains a challenge for clinicians, especially with the emergence of degenerative affection such as fatty infiltration that exacerbate poor tendon-bone healing. In this study, we proposed a cocktail-like hydrogel with a four-layer structure (BMSCs+gNC@GH) for enhancing fatty infiltrated tendon-bone healing. As collagen and hyaluronic acid are the main biomacromolecules that constitute the extracellular matrix of enthesis tissue, this hydrogel was composed of UV-curable gelatin/hyaluronic acid (GelMA/HAMA) dual network gel (GH) with nanoclay (NC) and stem cells loaded. The results showed that NC exhibited a cocktail-like gradient distribution in GH, which effectively mimicked the structure of native enthesis and supported the long-term culture and encapsulation of BMSCs. What's more, the gradient variation of NC provided a biological signal for promoting gradient osteogenic differentiation of cells. Based on the in vivo results, BMSCs+gNC@GH effectively promoted fibrocartilage layer regeneration at the tendon-bone interface and inhibited fatty infiltration. Therefore, BMSCs+gNC@GH group exhibited better biomechanical properties. Thus, this cocktail-like implant may be a promising tissue-engineered scaffold for tendon-bone healing, and it provides a new idea for the development of scaffolds with the function of inhibiting degeneration.
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Affiliation(s)
- Wei Ji
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China
| | - Fei Han
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China
| | - Xian Feng
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China
| | - Lei Shi
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China
| | - Hongdong Ma
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China
| | - Yue Lu
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China.
| | - Ran Tao
- Department of Orthopaedics, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China.
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8
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Buss DJ, Rechav K, Reznikov N, McKee MD. Mineral tessellation in mouse enthesis fibrocartilage, Achilles tendon, and Hyp calcifying enthesopathy: A shared 3D mineralization pattern. Bone 2023:116818. [PMID: 37295663 DOI: 10.1016/j.bone.2023.116818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/17/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023]
Abstract
The hallmark of enthesis architecture is the 3D compositional and structural gradient encompassing four tissue zones - tendon/ligament, uncalcified fibrocartilage, calcified fibrocartilage and bone. This functional gradient accommodates the large stiffness differential between calcified bone and uncalcified tendon/ligament. Here we analyze in 3D the organization of the mouse Achilles enthesis and mineralizing Achilles tendon in comparison to lamellar bone. We use correlative, multiscale high-resolution volume imaging methods including μCT with submicrometer resolution and FIB-SEM tomography (both with deep learning-based image segmentation), and TEM and SEM imaging, to describe ultrastructural features of physiologic, age-related and aberrant mineral patterning. We applied these approaches to murine wildtype (WT) Achilles enthesis tissues to describe in normal calcifying fibrocartilage a crossfibrillar mineral tessellation pattern similar to that observed in lamellar bone, but with greater variance in mineral tesselle morphology and size. We also examined Achilles enthesis structure in Hyp mice, a murine model for the inherited osteomalacic disease X-linked hypophosphatemia (XLH) with calcifying enthesopathy. In Achilles enthesis fibrocartilage of Hyp mice, we show defective crossfibrillar mineral tessellation similar to that which occurs in Hyp lamellar bone. At the cellular level in fibrocartilage, unlike in bone where enlarged osteocyte mineral lacunae are found as peri-osteocytic lesions, mineral lacunar volumes for fibrochondrocytes did not differ between WT and Hyp mice. While both WT and Hyp aged mice demonstrate Achilles tendon midsubstance ectopic mineralization, a consistently defective mineralization pattern was observed in Hyp mice. Strong immunostaining for osteopontin was observed at all mineralization sites examined in both WT and Hyp mice. Taken together, this new 3D ultrastructural information describes details of common mineralization trajectories for enthesis, tendon and bone, which in Hyp/XLH are defective.
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Affiliation(s)
- Daniel J Buss
- Department of Anatomy and Cell Biology, School of Biomedical Sciences, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Katya Rechav
- Electron Microscopy Unit, Weizmann Institute of Science, Rehovot, Israel
| | - Natalie Reznikov
- Department of Anatomy and Cell Biology, School of Biomedical Sciences, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada; Department of Bioengineering, Faculty of Engineering, McGill University, Montreal, Quebec, Canada; Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Marc D McKee
- Department of Anatomy and Cell Biology, School of Biomedical Sciences, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada; Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, Quebec, Canada.
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9
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Tian B, Zhang M, Kang X. Strategies to promote tendon-bone healing after anterior cruciate ligament reconstruction: Present and future. Front Bioeng Biotechnol 2023; 11:1104214. [PMID: 36994361 PMCID: PMC10040767 DOI: 10.3389/fbioe.2023.1104214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 03/02/2023] [Indexed: 03/16/2023] Open
Abstract
At present, anterior cruciate ligament (ACL) reconstruction still has a high failure rate. Tendon graft and bone tunnel surface angiogenesis and bony ingrowth are the main physiological processes of tendon-bone healing, and also the main reasons for the postoperative efficacy of ACL reconstruction. Poor tendon-bone healing has been also identified as one of the main causes of unsatisfactory treatment outcomes. The physiological process of tendon-bone healing is complicated because the tendon-bone junction requires the organic fusion of the tendon graft with the bone tissue. The failure of the operation is often caused by tendon dislocation or scar healing. Therefore, it is important to study the possible risk factors for tendon-bone healing and strategies to promote it. This review comprehensively analyzed the risk factors contributing to tendon-bone healing failure after ACL reconstruction. Additionally, we discuss the current strategies used to promote tendon-bone healing following ACL reconstruction.
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10
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Baawad A, Jacho D, Hamil T, Yildirim-Ayan E, Kim DS. Polysaccharide-Based Composite Scaffolds for Osteochondral and Enthesis Regeneration. TISSUE ENGINEERING. PART B, REVIEWS 2023; 29:123-140. [PMID: 36181352 DOI: 10.1089/ten.teb.2022.0114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The rotator cuff and Achilles tendons along with the anterior cruciate ligament (ACL) are frequently injured with limited healing capacity. At the soft-hard tissue interface, enthesis is prone to get damaged and its regeneration in osteochondral defects is essential for complete healing. The current clinical techniques used in suturing procedures to reattach tendons to bones need much improvement for the generation of the native interface tissue, that is, enthesis, for patients to regain their full functions. Recently, inspired by the composite native tissue, much effort has been made to fabricate composite scaffolds for enthesis tissue regeneration. This review first focuses on the studies that used composite scaffolds for the regeneration of enthesis. Then, the use of polysaccharides for osteochondral tissue engineering is reviewed and their potential for enthesis regeneration is presented based on their supporting effects on osteogenesis and chondrogenesis. Gellan gum (GG) is selected and reviewed as a promising polysaccharide due to its unique osteogenic and chondrogenic activities that help avoid the inherent weakness of dissimilar materials in composite scaffolds. In addition, original preliminary results showed that GG supports collagen type I production and upregulation of osteogenic marker genes. Impact Statement Enthesis regeneration is essential for complete and functional healing of tendon and ligament tissues. Current suturing techniques to reattach the tendon/ligament to bones have high failure rates. This review highlights the studies on biomimetic scaffolds aimed to regenerate enthesis. In addition, the potential of using polysaccharides to regenerate enthesis is discussed based on their ability to regenerate osteochondral tissues. Gellan gum is presented as a promising biopolymer that can be modified to simultaneously support bone and cartilage regeneration by providing structural continuity for the scaffold.
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Affiliation(s)
- Abdullah Baawad
- Department of Chemical Engineering, University of Toledo, Toledo, Ohio, USA
| | - Diego Jacho
- Department of Bioengineering, University of Toledo, Toledo, Ohio, USA
| | - Taijah Hamil
- Department of Chemical Engineering, University of Toledo, Toledo, Ohio, USA
| | - Eda Yildirim-Ayan
- Department of Bioengineering, University of Toledo, Toledo, Ohio, USA
| | - Dong-Shik Kim
- Department of Chemical Engineering, University of Toledo, Toledo, Ohio, USA
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11
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Zhang H, Ma Y, Wang Y, Niu L, Zou R, Zhang M, Liu H, Genin GM, Li A, Xu F. Rational Design of Soft-Hard Interfaces through Bioinspired Engineering. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2204498. [PMID: 36228093 DOI: 10.1002/smll.202204498] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Soft-hard tissue interfaces in nature present a diversity of hierarchical transitions in composition and structure to address the challenge of stress concentrations that would otherwise arise at their interface. The translation of these into engineered materials holds promise for improved function of biomedical interfaces. Here, soft-hard tissue interfaces found in the body in health and disease, and the application of the diverse, functionally graded, and hierarchical structures that they present to bioinspired engineering materials are reviewed. A range of such bioinspired engineering materials and associated manufacturing technologies that are on the horizon in interfacial tissue engineering, hydrogel bioadhesion at the interfaces, and healthcare and medical devices are described.
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Affiliation(s)
- Hui Zhang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, 710004, P. R. China
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, P. R. China
| | - Yufei Ma
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, P. R. China
| | - Yijie Wang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, 710004, P. R. China
| | - Lin Niu
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, 710004, P. R. China
| | - Rui Zou
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, 710004, P. R. China
| | - Min Zhang
- State Key Laboratory of Military Stomatology, Department of General Dentistry and Emergency, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China
| | - Hao Liu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, P. R. China
| | - Guy M Genin
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, P. R. China
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, St. Louis, MO, 63130, USA
- NSF Science and Technology Center for Engineering MechanoBiology, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Ang Li
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, 710004, P. R. China
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, P. R. China
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12
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Zhang T, Li S, Chen Y, Xiao H, Wang L, Hu J, Xu D, Lu H. Characterize the microstructure change after tendon enthesis injury using synchrotron radiation μCT. J Orthop Res 2022; 40:2678-2687. [PMID: 35076113 DOI: 10.1002/jor.25289] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 01/12/2022] [Accepted: 01/23/2022] [Indexed: 02/04/2023]
Abstract
The microstructure of the bone-tendon interface (BTI) deserves in-depth investigation. In this study, we first aimed to extend the application of synchrotron radiation μCT to characterize the gradient structure of supraspinatus tendon (SST) enthesis, from both tissue morphology to cell distribution. Second, to acquire detailed morphological information of SST enthesis when after injury. Our results showed that in normal enthesis, the phenotype of chondrocyte in BTI was dependent on its distance to subchondral bone. After injury, the fibrocartilage cells were disrupted, as evidenced by reduced lacunae size. Our observation may partly explain the loss of BTI mechanical properties after injury, and we believe the application of synchrotron radiation microcomputed tomography will have promising potential for characterizing the morphology changes in enthesis and for evaluating the therapeutic effects of interventions in preclinical studies.
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Affiliation(s)
- Tao Zhang
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Shengcan Li
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Yang Chen
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Han Xiao
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Linfeng Wang
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Jianzhong Hu
- Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Department of Spine Surgery and Orthopaedics, Xiangya Hospital, Central South University, Changsha, China
| | - Daqi Xu
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Hongbin Lu
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
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13
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Cuff AR, Wiseman ALA, Bishop PJ, Michel KB, Gaignet R, Hutchinson JR. Anatomically grounded estimation of hindlimb muscle sizes in Archosauria. J Anat 2022; 242:289-311. [PMID: 36206401 PMCID: PMC9877486 DOI: 10.1111/joa.13767] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/26/2022] [Accepted: 08/31/2022] [Indexed: 02/01/2023] Open
Abstract
In vertebrates, active movement is driven by muscle forces acting on bones, either directly or through tendinous insertions. There has been much debate over how muscle size and force are reflected by the muscular attachment areas (AAs). Here we investigate the relationship between the physiological cross-sectional area (PCSA), a proxy for the force production of the muscle, and the AA of hindlimb muscles in Nile crocodiles and five bird species. The limbs were held in a fixed position whilst blunt dissection was carried out to isolate the individual muscles. AAs were digitised using a point digitiser, before the muscle was removed from the bone. Muscles were then further dissected and fibre architecture was measured, and PCSA calculated. The raw measures, as well as the ratio of PCSA to AA, were studied and compared for intra-observer error as well as intra- and interspecies differences. We found large variations in the ratio between AAs and PCSA both within and across species, but muscle fascicle lengths are conserved within individual species, whether this was Nile crocodiles or tinamou. Whilst a discriminant analysis was able to separate crocodylian and avian muscle data, the ratios for AA to cross-sectional area for all species and most muscles can be represented by a single equation. The remaining muscles have specific equations to represent their scaling, but equations often have a relatively high success at predicting the ratio of muscle AA to PCSA. We then digitised the muscle AAs of Coelophysis bauri, a dinosaur, to estimate the PCSAs and therefore maximal isometric muscle forces. The results are somewhat consistent with other methods for estimating force production, and suggest that, at least for some archosaurian muscles, that it is possible to use muscle AA to estimate muscle sizes. This method is complementary to other methods such as digital volumetric modelling.
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Affiliation(s)
- Andrew R. Cuff
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK,Human Anatomy Resource CentreUniversity of LiverpoolLiverpoolUK
| | - Ashleigh L. A. Wiseman
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
| | - Peter J. Bishop
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK,Museum of Comparative Zoology and Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeUSA,Geosciences ProgramQueensland MuseumBrisbaneQueenslandAustralia
| | - Krijn B. Michel
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
| | - Raphäelle Gaignet
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
| | - John R. Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
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14
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Wang L, Jiang J, Lin H, Zhu T, Cai J, Su W, Chen J, Xu J, Li Y, Wang J, Zhang K, Zhao J. Advances in Regenerative Sports Medicine Research. Front Bioeng Biotechnol 2022; 10:908751. [PMID: 35646865 PMCID: PMC9136559 DOI: 10.3389/fbioe.2022.908751] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 04/21/2022] [Indexed: 01/08/2023] Open
Abstract
Regenerative sports medicine aims to address sports and aging-related conditions in the locomotor system using techniques that induce tissue regeneration. It also involves the treatment of meniscus and ligament injuries in the knee, Achilles’ tendon ruptures, rotator cuff tears, and cartilage and bone defects in various joints, as well as the regeneration of tendon–bone and cartilage–bone interfaces. There has been considerable progress in this field in recent years, resulting in promising steps toward the development of improved treatments as well as the identification of conundrums that require further targeted research. In this review the regeneration techniques currently considered optimal for each area of regenerative sports medicine have been reviewed and the time required for feasible clinical translation has been assessed. This review also provides insights into the direction of future efforts to minimize the gap between basic research and clinical applications.
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Affiliation(s)
- Liren Wang
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- Regenerative Sports Medicine and Translational Youth Science and Technology Innovation Workroom, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jia Jiang
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- Regenerative Sports Medicine and Translational Youth Science and Technology Innovation Workroom, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Regenerative Sports Medicine Lab of the Institute of Microsurgery on Extremities, Shanghai Jiao Tong University Affiliated Sixth People’ Hospital, Shanghai, China
| | - Hai Lin
- National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, China
| | - Tonghe Zhu
- School of Chemistry and Chemical Engineering, Shanghai Engineering Research Center of Pharmaceutical Intelligent Equipment, Shanghai Frontiers Science Research Center for Druggability of Cardiovascular Non-Coding RNA, Institute for Frontier Medical Technology, Shanghai University of Engineering Science, Shanghai, China
| | - Jiangyu Cai
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, China
| | - Wei Su
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Jiebo Chen
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Junjie Xu
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Yamin Li
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Jing Wang
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Kai Zhang
- National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, China
- *Correspondence: Kai Zhang, ; Jinzhong Zhao,
| | - Jinzhong Zhao
- Department of Sports Medicine, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- Regenerative Sports Medicine and Translational Youth Science and Technology Innovation Workroom, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Regenerative Sports Medicine Lab of the Institute of Microsurgery on Extremities, Shanghai Jiao Tong University Affiliated Sixth People’ Hospital, Shanghai, China
- *Correspondence: Kai Zhang, ; Jinzhong Zhao,
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15
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Qiu J, Ahn J, Qin D, Thomopoulos S, Xia Y. Biomimetic Scaffolds with a Mineral Gradient and Funnel-Shaped Channels for Spatially Controllable Osteogenesis. Adv Healthc Mater 2022; 11:e2100828. [PMID: 34050610 DOI: 10.1002/adhm.202100828] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/15/2021] [Indexed: 12/14/2022]
Abstract
A facile method is described herein for generating a mineral gradient in a biodegradable polymer scaffold. The gradient is achieved by swelling a composite film made of polycaprolactone (PCL) and hydroxyapatite (HAp) nanoparticles with a PCL solution. During the swelling process, the solvent and PCL polymer chains diffuse into the composite film, generating a gradient in HAp density at their interface. The thickness of the mineral gradient can be tuned by varying the extent of swelling to match the length scale of the natural tendon-to-bone attachment (20-60 µm). When patterned with an array of funnel-shaped channels, the mineral gradient presents stem cells with spatial gradations in both biochemical cues (e.g., osteoinductivity and conductivity associated with the HAp nanoparticles) and mechanical cues (e.g., substrate stiffness) to stimulate their differentiation into a graded distribution of cell phenotypes. This new class of biomimetic scaffolds holds great promise for facilitating the regeneration of the injured tendon-to-bone attachment by stimulating the formation of a functionally graded interface.
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Affiliation(s)
- Jichuan Qiu
- The Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University Atlanta GA 30332 USA
| | - Jaewan Ahn
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA 30332 USA
| | - Dong Qin
- School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA 30332 USA
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery Department of Biomedical Engineering Columbia University New York NY 10032 USA
| | - Younan Xia
- The Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University Atlanta GA 30332 USA
- School of Chemistry and Biochemistry School of Chemical and Biomolecular Engineering Georgia Institute of Technology Atlanta GA 30332 USA
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16
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Abstract
Tendons are collagen-rich musculoskeletal tissues that possess the mechanical strength needed to transfer forces between muscles and bones. The mechanical development and function of tendons are impacted by collagen crosslinks. However, there is a limited understanding of how collagen crosslinking is regulated in tendon during development and aging. Therefore, the objective of the present review was to highlight potential regulators of enzymatic and non-enzymatic collagen crosslinking and how they impact tendon function. The main collagen crosslinking enzymes include lysyl oxidase (LOX) and the lysyl oxidase-like isoforms (LOXL), whereas non-enzymatic crosslinking is mainly mediated by the formation of advanced glycation end products (AGEs). Regulators of the LOX and LOXL enzymes may include mechanical stimuli, mechanotransducive cell signaling pathways, sex hormones, transforming growth factor (TGF)β family, hypoxia, and interactions with intracellular or extracellular proteins. AGE accumulation in tendon is due to diabetic conditions and aging, and can be mediated by diet and mechanical stimuli. The formation of these enzymatic and non-enzymatic collagen crosslinks plays a major role in tendon biomechanics and in the mechanisms of force transfer. A more complete understanding of how enzymatic and non-enzymatic collagen crosslinking is regulated in tendon will better inform tissue engineering and regenerative therapies aimed at restoring the mechanical function of damaged tendons.
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Affiliation(s)
- A.J. Ellingson
- Chemical and Biological Engineering, University of Idaho, Moscow, ID, USA
| | - N.M. Pancheri
- Chemical and Biological Engineering, University of Idaho, Moscow, ID, USA
| | - N.R. Schiele
- Chemical and Biological Engineering, University of Idaho, Moscow, ID, USA,Address for correspondence: Nathan R. Schiele, Chemical and Biological Engineering, University of Idaho, 875 Perimeter Dr. MS 0904, Moscow, ID, USA. Telephone number: 208 8859063
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17
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Golman M, Abraham AC, Kurtaliaj I, Marshall BP, Hu YJ, Schwartz AG, Guo XE, Birman V, Thurner PJ, Genin GM, Thomopoulos S. Toughening mechanisms for the attachment of architectured materials: The mechanics of the tendon enthesis. SCIENCE ADVANCES 2021; 7:eabi5584. [PMID: 34826240 PMCID: PMC8626067 DOI: 10.1126/sciadv.abi5584] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 10/06/2021] [Indexed: 05/09/2023]
Abstract
Architectured materials offer tailored mechanical properties but are limited in engineering applications due to challenges in maintaining toughness across their attachments. The enthesis connects tendon and bone, two vastly different architectured materials, and exhibits toughness across a wide range of loadings. Understanding the mechanisms by which this is achieved could inform the development of engineered attachments. Integrating experiments, simulations, and previously unexplored imaging that enabled simultaneous observation of mineralized and unmineralized tissues, we identified putative mechanisms of enthesis toughening in a mouse model and then manipulated these mechanisms via in vivo control of mineralization and architecture. Imaging uncovered a fibrous architecture within the enthesis that controls trade-offs between strength and toughness. In vivo models of pathology revealed architectural adaptations that optimize these trade-offs through cross-scale mechanisms including nanoscale protein denaturation, milliscale load-sharing, and macroscale energy absorption. Results suggest strategies for optimizing architecture for tough bimaterial attachments in medicine and engineering.
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Affiliation(s)
- Mikhail Golman
- Department of Orthopedic Surgery, Columbia University, New York, NY 10032, USA
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
| | - Adam C. Abraham
- Department of Orthopedic Surgery, Columbia University, New York, NY 10032, USA
| | - Iden Kurtaliaj
- Department of Orthopedic Surgery, Columbia University, New York, NY 10032, USA
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
| | - Brittany P. Marshall
- Department of Orthopedic Surgery, Columbia University, New York, NY 10032, USA
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
| | - Yizhong Jenny Hu
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
| | - Andrea G. Schwartz
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University, St. Louis, MO 63130, USA
| | - X. Edward Guo
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
| | - Victor Birman
- Missouri University of Science and Technology, Rolla, MO 65409, USA
| | - Philipp J. Thurner
- Institute of Lightweight Design and Structural Biomechanics, Vienna University of Technology, Vienna, Austria
| | - Guy M. Genin
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University, St. Louis, MO 63130, USA
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Columbia University, New York, NY 10032, USA
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
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18
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Tits A, Plougonven E, Blouin S, Hartmann MA, Kaux JF, Drion P, Fernandez J, van Lenthe GH, Ruffoni D. Local anisotropy in mineralized fibrocartilage and subchondral bone beneath the tendon-bone interface. Sci Rep 2021; 11:16534. [PMID: 34400706 PMCID: PMC8367976 DOI: 10.1038/s41598-021-95917-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 08/02/2021] [Indexed: 12/19/2022] Open
Abstract
The enthesis allows the insertion of tendon into bone thanks to several remarkable strategies. This complex and clinically relevant location often features a thin layer of fibrocartilage sandwiched between tendon and bone to cope with a highly heterogeneous mechanical environment. The main purpose of this study was to investigate whether mineralized fibrocartilage and bone close to the enthesis show distinctive three-dimensional microstructural features, possibly to enable load transfer from tendon to bone. As a model, the Achilles tendon-calcaneus bone system of adult rats was investigated with histology, backscattered electron imaging and micro-computed tomography. The microstructural porosity of bone and mineralized fibrocartilage in different locations including enthesis fibrocartilage, periosteal fibrocartilage and bone away from the enthesis was characterized. We showed that calcaneus bone presents a dedicated protrusion of low porosity where the tendon inserts. A spatially resolved analysis of the trabecular network suggests that such protrusion may promote force flow from the tendon to the plantar ligament, while partially relieving the trabecular bone from such a task. Focusing on the tuberosity, highly specific microstructural aspects were highlighted. Firstly, the interface between mineralized and unmineralized fibrocartilage showed the highest roughness at the tuberosity, possibly to increase failure resistance of a region carrying large stresses. Secondly, fibrochondrocyte lacunae inside mineralized fibrocartilage, in analogy with osteocyte lacunae in bone, had a predominant alignment at the enthesis and a rather random organization away from it. Finally, the network of subchondral channels inside the tuberosity was highly anisotropic when compared to contiguous regions. This dual anisotropy of subchondral channels and cell lacunae at the insertion may reflect the alignment of the underlying collagen network. Our findings suggest that the microstructure of fibrocartilage may be linked with the loading environment. Future studies should characterize those microstructural aspects in aged and or diseased conditions to elucidate the poorly understood role of bone and fibrocartilage in enthesis-related pathologies.
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Affiliation(s)
- Alexandra Tits
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Quartier Polytech 1, Allée de la Découverte 9, 4000, Liège, Belgium
| | - Erwan Plougonven
- Chemical Engineering Department, University of Liège, Liège, Belgium
| | - Stéphane Blouin
- Ludwig Boltzmann Institute of Osteology, Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Markus A Hartmann
- Ludwig Boltzmann Institute of Osteology, Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Jean-François Kaux
- Department of Physical Medicine and Sports Traumatology, University of Liège and University Hospital of Liège, Liège, Belgium
| | - Pierre Drion
- Experimental Surgery Unit, GIGA and Credec, University of Liege, Liege, Belgium
| | - Justin Fernandez
- Auckland Bioengineering Institute and Department of Engineering Science, University of Auckland, Auckland, New Zealand
| | | | - Davide Ruffoni
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Quartier Polytech 1, Allée de la Découverte 9, 4000, Liège, Belgium.
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19
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Tits A, Ruffoni D. Joining soft tissues to bone: Insights from modeling and simulations. Bone Rep 2021; 14:100742. [PMID: 34150954 PMCID: PMC8190669 DOI: 10.1016/j.bonr.2020.100742] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/14/2020] [Accepted: 12/18/2020] [Indexed: 01/16/2023] Open
Abstract
Entheses are complex multi-tissue regions of the musculoskeletal system serving the challenging task of connecting highly dissimilar materials such as the compliant tendon to the much stiffer bone, over a very small region. The first aim of this review is to highlight mathematical and computational models that have been developed to investigate the many attachment strategies present at entheses at different length scales. Entheses are also relevant in the medical context due to the high prevalence of orthopedic injuries requiring the reattachment of tendons or ligaments to bone, which are associated with a rather poor long-term clinical outcome. The second aim of the review is to report on the computational works analyzing the whole tendon to bone complex as well as targeting orthopedic relevant issues. Modeling approaches have provided important insights on anchoring mechanisms and surgical repair strategies, that would not have been revealed with experiments alone. We intend to demonstrate the necessity of including, in future models, an enriched description of enthesis biomechanical behavior in order to unravel additional mechanical cues underlying the development, the functioning and the maintaining of such a complex biological interface as well as to enhance the development of novel biomimetic adhesive, attachment procedures or tissue engineered implants.
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Affiliation(s)
- Alexandra Tits
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Liège, Belgium
| | - Davide Ruffoni
- Mechanics of Biological and Bioinspired Materials Laboratory, Department of Aerospace and Mechanical Engineering, University of Liège, Liège, Belgium
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20
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Yang R, Li G, Zhuang C, Yu P, Ye T, Zhang Y, Shang P, Huang J, Cai M, Wang L, Cui W, Deng L. Gradient bimetallic ion-based hydrogels for tissue microstructure reconstruction of tendon-to-bone insertion. SCIENCE ADVANCES 2021; 7:eabg3816. [PMID: 34162547 PMCID: PMC8221628 DOI: 10.1126/sciadv.abg3816] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 04/29/2021] [Indexed: 05/11/2023]
Abstract
Although gradients play an essential role in guiding the function of tissues, achieving synchronous regeneration of gradient tissue injuries remains a challenge. Here, a gradient bimetallic (Cu and Zn) ion-based hydrogel was first constructed via the one-step coordinative crosslinking of sulfhydryl groups with copper and zinc ions for the microstructure reconstruction of the tendon-to-bone insertion. In this bimetallic hydrogel system, zinc and copper ions could not only act as crosslinkers but also provide strong antibacterial effects and induce regenerative capacity in vitro. The capability of hydrogels in simultaneously promoting tenogenesis and osteogenesis was further verified in a rat rotator cuff tear model. It was found that the Cu/Zn gradient layer could induce considerable collagen and fibrocartilage arrangement and ingrowth at the tendon-to-bone interface. Overall, the gradient bimetallic ion-based hydrogel ensures accessibility and provides opportunities to regenerate inhomogeneous tissue with physiological complexity or interface tissue.
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Affiliation(s)
- Renhao Yang
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Gen Li
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Chengyu Zhuang
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Pei Yu
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Tingjun Ye
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Yin Zhang
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Peiyang Shang
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Jingjing Huang
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China
| | - Ming Cai
- Department of Orthopaedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301 Middle Yanchang Road, Shanghai 200072, P. R. China
| | - Lei Wang
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China.
| | - Wenguo Cui
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China.
| | - Lianfu Deng
- Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China.
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21
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Zhu C, Qiu J, Thomopoulos S, Xia Y. Augmenting Tendon-to-Bone Repair with Functionally Graded Scaffolds. Adv Healthc Mater 2021; 10:e2002269. [PMID: 33694312 PMCID: PMC8102396 DOI: 10.1002/adhm.202002269] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 02/24/2021] [Indexed: 12/14/2022]
Abstract
Tendon-to-bone repair often fails because the functionally graded attachment is not regenerated during the healing process. Biomimetic scaffolds that recapitulate the unique features of the native tendon-to-bone attachment hold great promise for enhancing the healing process. Among various types of scaffolds that are developed and evaluated for tendon-to-bone repair, those with gradations (in either a stratified or a continuous fashion) in composition, structure, mechanical properties, and cell phenotype have gained the most attention. In this progress report, the recent efforts in the rational design and fabrication of functionally graded scaffolds based upon electrospun nanofiber mats and inverse opal structures, as well as the evaluation of their applications in augmenting tendon-to-bone repair, are reviewed. This report concludes with perspectives on the necessary future steps for clinical translation of the scaffolds.
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Affiliation(s)
- Chunlei Zhu
- Key Laboratory of Functional Polymer Materials of Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Jichuan Qiu
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Columbia University, New York, NY, 10032, USA
- Department of Biomedical Engineering, Columbia University, New York, NY, 10027, USA
| | - Younan Xia
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
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22
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Chen B, Liang Y, Zhang J, Bai L, Xu M, Han Q, Han X, Xiu J, Li M, Zhou X, Guo B, Yin Z. Synergistic enhancement of tendon-to-bone healing via anti-inflammatory and pro-differentiation effects caused by sustained release of Mg 2+/curcumin from injectable self-healing hydrogels. Am J Cancer Res 2021; 11:5911-5925. [PMID: 33897889 PMCID: PMC8058719 DOI: 10.7150/thno.56266] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 03/18/2021] [Indexed: 12/18/2022] Open
Abstract
Poor healing response after rotator cuff reconstruction is multifactorial, with the inflammatory microenvironment and deficiency of stem cell differentiation factors at the lesion site being most relevant. However, there is a lack of effective tissue engineering strategies that can simultaneously exert anti-inflammatory and pro-differentiation effects to promote rotator cuff healing. Methods: In this study, we synthesized and characterized a novel active drug delivery vector that successfully overcame the challenge of simultaneous high-efficiency loading and controlled release of Mg2+ and curcumin. The anti-inflammatory and pro-differentiation effects of the composite hydrogel were evaluated in vitro and in vivo. Moreover, healing of the rotator cuff tendon-to-bone interface was studied by histology, immunofluorescence, and biomechanical tests. Results: The composite hydrogel exhibited excellent biocompatibility and injectability, good adhesiveness, and rapid self-healing. The released curcumin showed obvious anti-inflammatory and antioxidation effects, which protected stem cells and tendon matrix. Furthermore, released Mg2+ promoted stem cell aggregation and chondrogenesis. Moreover, biomechanical tests and histological results of a rat rotator cuff tear model at 8 weeks after surgery indicated that the composite hydrogel significantly enhanced tendon-to-bone healing. Conclusions: The composite hydrogel mediated sustained in situ release of curcumin and Mg2+ to effectively promote rotator cuff tendon-to-bone healing via anti-inflammatory and pro-differentiation effects. Therefore, this composite hydrogel offers significant promise for rotator cuff repair.
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23
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Karakostis FA, Harvati K. New horizons in reconstructing past human behavior: Introducing the "Tübingen University Validated Entheses-based Reconstruction of Activity" method. Evol Anthropol 2021; 30:185-198. [PMID: 33764627 DOI: 10.1002/evan.21892] [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] [Received: 05/17/2020] [Revised: 09/28/2020] [Accepted: 03/03/2021] [Indexed: 02/05/2023]
Abstract
An accurate reconstruction of habitual activities in past populations and extinct hominin species is a paramount goal of paleoanthropological research, as it can elucidate the evolution of human behavior and the relationship between culture and biology. Variation in muscle attachment (entheseal) morphology has been considered an indicator of habitual activity, and many attempts have been made to use it for this purpose. However, its interpretation remains equivocal due to methodological shortcomings and a paucity of supportive experimental data. Through a series of studies, we have introduced a novel and precise methodology that focuses on reconstructing muscle synergies based on three-dimensional and multivariate analyses among entheses. This approach was validated using uniquely documented anthropological samples, experimental animal studies, histological observations, and geometric morphometrics. Here, we detail, synthesize, and critically discuss the findings of these studies, which overall point to the great potential of entheses in elucidating aspects of past human behavior.
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Affiliation(s)
- Fotios Alexandros Karakostis
- DFG (Deutsche Forschungsgemeinschaft) Center for Advanced Studies "Words, Bones, Genes, Tools," Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Katerina Harvati
- DFG (Deutsche Forschungsgemeinschaft) Center for Advanced Studies "Words, Bones, Genes, Tools," Eberhard Karls University of Tübingen, Tübingen, Germany.,Paleoanthropology, Senckenberg Centre for Human Evolution and Palaeoenvironment, Institute of Archaeological Sciences, University of Tübingen, Tübingen, Germany
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24
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Lim TK, Dorthé E, Williams A, D'Lima DD. Nanofiber Scaffolds by Electrospinning for Rotator Cuff Tissue Engineering. Chonnam Med J 2021; 57:13-26. [PMID: 33537215 PMCID: PMC7840345 DOI: 10.4068/cmj.2021.57.1.13] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/11/2022] Open
Abstract
Rotator cuff tears continue to be at risk of retear or failure to heal after surgical repair, despite the use of various surgical techniques, which stimulate development of novel scaffolding strategies. They should be able to address the known causes of failure after the conventional rotator cuff repair: (1) failure to reproduce the normal tendon healing process, (2) resultant failure to reproduce four zones of the enthesis, and (3) failure to attain sufficient mechanical strength after repair. Nanofiber scaffolds are suited for this application because they can be engineered to mimic the ultrastructure and properties of the native rotator cuff tendon. Among various methods for tissue-engineered nanofibers, electrospinning has recently been highlighted in the rotator cuff field. Electrospinning can create fibrous and porous structures that resemble natural tendon's extracellular matrix. Other advantages include the ability to create relatively large surface-to-volume ratios, the ability to control fiber size from the micro to the nano scale, and the flexibility of material choices. In this review, we will discuss the anatomical and mechanical features of the rotator cuff tendon, their potential impacts on improper healing after repair, and the current knowledge of the use of electrospinning for rotator cuff tissue engineering.
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Affiliation(s)
- Tae Kang Lim
- Department of Orthopaedic Surgery, Nowon Eulji Medical Center, Eulji University School of Medicine, Seoul, Korea.,Shiley Center for Orthopedic Research & Education at Scripps Clinic, CA, USA.,Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
| | - Erik Dorthé
- Shiley Center for Orthopedic Research & Education at Scripps Clinic, CA, USA.,Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
| | - Austin Williams
- Shiley Center for Orthopedic Research & Education at Scripps Clinic, CA, USA.,Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
| | - Darryl D D'Lima
- Shiley Center for Orthopedic Research & Education at Scripps Clinic, CA, USA.,Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
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25
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Siadat SM, Zamboulis DE, Thorpe CT, Ruberti JW, Connizzo BK. Tendon Extracellular Matrix Assembly, Maintenance and Dysregulation Throughout Life. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1348:45-103. [PMID: 34807415 DOI: 10.1007/978-3-030-80614-9_3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In his Lissner Award medal lecture in 2000, Stephen Cowin asked the question: "How is a tissue built?" It is not a new question, but it remains as relevant today as it did when it was asked 20 years ago. In fact, research on the organization and development of tissue structure has been a primary focus of tendon and ligament research for over two centuries. The tendon extracellular matrix (ECM) is critical to overall tissue function; it gives the tissue its unique mechanical properties, exhibiting complex non-linear responses, viscoelasticity and flow mechanisms, excellent energy storage and fatigue resistance. This matrix also creates a unique microenvironment for resident cells, allowing cells to maintain their phenotype and translate mechanical and chemical signals into biological responses. Importantly, this architecture is constantly remodeled by local cell populations in response to changing biochemical (systemic and local disease or injury) and mechanical (exercise, disuse, and overuse) stimuli. Here, we review the current understanding of matrix remodeling throughout life, focusing on formation and assembly during the postnatal period, maintenance and homeostasis during adulthood, and changes to homeostasis in natural aging. We also discuss advances in model systems and novel tools for studying collagen and non-collagenous matrix remodeling throughout life, and finally conclude by identifying key questions that have yet to be answered.
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Affiliation(s)
| | - Danae E Zamboulis
- Institute of Life Course and Medical Sciences, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK
| | - Chavaunne T Thorpe
- Comparative Biomedical Sciences, The Royal Veterinary College, University of London, London, UK
| | - Jeffrey W Ruberti
- Department of Bioengineering, Northeastern University, Boston, MA, USA
| | - Brianne K Connizzo
- Department of Biomedical Engineering, Boston University, Boston, MA, USA.
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26
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Brassey CA, Behnsen J, Gardiner JD. Postcopulatory sexual selection and the evolution of shape complexity in the carnivoran baculum. Proc Biol Sci 2020; 287:20201883. [PMID: 33049172 PMCID: PMC7657853 DOI: 10.1098/rspb.2020.1883] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The baculum is an enigmatic bone within the mammalian glans penis, and the driving forces behind its often bizarre shape have captivated evolutionary biologists for over a century. Hypotheses for the function of the baculum include aiding in intromission, stimulating females and assisting with prolonged mating. Previous attempts to test these hypotheses have focused on the gross size of the baculum and have failed to reach a consensus. We conducted three-dimensional imaging and apply a new method to quantify three-dimensional shape complexity in the carnivoran baculum. We show that socially monogamous species are evolving towards complex-shaped bacula, whereas group-living species are evolving towards simple bacula. Overall three-dimensional baculum shape complexity is not related to relative testes mass, but tip complexity is higher in induced ovulators and species engaging in prolonged copulation. Our study provides evidence of postcopulatory sexual selection pressures driving three-dimensional shape complexity in the carnivore baculum.
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Affiliation(s)
- Charlotte A Brassey
- Department of Natural Sciences, Manchester Metropolitan University, M1 5GD, UK
| | - Julia Behnsen
- Manchester X-ray Imaging Facility, University of Manchester, M13 9PL, UK
| | - James D Gardiner
- Institute of Ageing and Chronic Disease, University of Liverpool, L7 8TX, UK
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27
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Liu Y, Schwartz AG, Hong Y, Peng X, Xu F, Thomopoulos S, Genin GM. Correction of bias in the estimation of cell volume fraction from histology sections. J Biomech 2020; 104:109705. [PMID: 32247525 DOI: 10.1016/j.jbiomech.2020.109705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 01/10/2020] [Accepted: 02/20/2020] [Indexed: 10/24/2022]
Abstract
Accurate determination of the fraction of a tissue's volume occupied by cells is critical for studying tissue development, pathology, and biomechanics. For example, homogenization methods that predict the function and responses of tissues based upon the properties of the tissue's constituents require estimates of cell volume fractions. A common way to estimate cellular volume fraction is to image cells in thin, planar histologic sections, and then invoke either the Delesse or the Glagolev principle to estimate the volume fraction from the measured area fraction. The Delesse principle relies upon the observation that for randomly aligned, identical features, the expected value of the observed area fraction of a phase equals the volume fraction of that phase, and the Glagolev principle relies on a similar observation for random rather than planar sampling. These methods are rigorous for analysis of a polished, opaque rock sections and for histologic sections that are thin compared to the characteristic length scale of the cells. However, when histologic slices cannot be cut sufficiently thin, a bias will be introduced. Although this bias - known as the Holmes effect in petrography - has been resolved for opaque spheres in a transparent matrix, it has not been addressed for histologic sections presenting the opposite problem, namely transparent cells in an opaque matrix. In this note, we present a scheme for correcting the bias in volume fraction estimates for transparent components in a relatively opaque matrix.
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Affiliation(s)
- Yanxin Liu
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, United States
| | - Andrea G Schwartz
- Department of Orthopaedic Surgery, Washington University School of Medicine, United States
| | - Yuan Hong
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, United States; NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, United States; Bioinspired Engineering and Biomechanics Center, School of Life Sciences and Technology, Xi'an Jiaotong University, China
| | - Xiangjun Peng
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, United States; NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, United States; Bioinspired Engineering and Biomechanics Center, School of Life Sciences and Technology, Xi'an Jiaotong University, China
| | - Feng Xu
- Bioinspired Engineering and Biomechanics Center, School of Life Sciences and Technology, Xi'an Jiaotong University, China
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Department of Biomedical Engineering, Columbia University, United States
| | - Guy M Genin
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, United States; NSF Science and Technology Center for Engineering Mechanobiology, Washington University in St. Louis, United States; Bioinspired Engineering and Biomechanics Center, School of Life Sciences and Technology, Xi'an Jiaotong University, China.
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28
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Tarafder S, Brito JA, Minhas S, Effiong L, Thomopoulos S, Lee CH. In situ tissue engineering of the tendon-to-bone interface by endogenous stem/progenitor cells. Biofabrication 2019; 12:015008. [PMID: 31561236 PMCID: PMC6904927 DOI: 10.1088/1758-5090/ab48ca] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The long-term success of surgical repair of rotator cuff tears is largely dependent on restoration of a functional tendon-to-bone interface. We implemented micro-precise spatiotemporal delivery of growth factors in three-dimensional printed scaffolds for integrative regeneration of a fibrocartilaginous tendon-to-bone interface. Sustained and spatially controlled release of tenogenic, chondrogenic and osteogenic growth factors was achieved using microsphere-based delivery carriers embedded in thin membrane-like scaffolds. In vitro, the scaffolds embedded with spatiotemporal delivery of growth factors successfully guided regional differentiation of mesenchymal progenitor cells, forming multiphase tissues with tendon-like, cartilage-like and bone-like regions. In vivo, when implanted at the interface between the supraspinatus tendon and the humeral head in a rat rotator cuff repair model, these scaffolds promoted recruitment of endogenous tendon progenitor cells followed by integrative healing of tendon and bone via re-formation of strong fibrocartilaginous interfaces. Our findings demonstrate the potential of in situ tissue engineering of tendon-to-bone interfaces by endogenous progenitor cells. The in situ tissue engineering approach shows translational potential for improving outcomes after rotator cuff repair.
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Affiliation(s)
- Solaiman Tarafder
- Regenerative Engineering Laboratory, Columbia University Medical Center, 630 W. 168th Street, VC12-230, NY 10032, New York
| | - John A Brito
- Regenerative Engineering Laboratory, Columbia University Medical Center, 630 W. 168th Street, VC12-230, NY 10032, New York
| | - Sumeet Minhas
- Regenerative Engineering Laboratory, Columbia University Medical Center, 630 W. 168th Street, VC12-230, NY 10032, New York
| | - Linda Effiong
- Department of Orthopedic Surgery, Columbia University Medical Center, 650 W. 168th Street, BB14-1408, NY 10032, New York
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Columbia University Medical Center, 650 W. 168th Street, BB14-1408, NY 10032, New York
- Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace, NY 10027, New York
| | - Chang H Lee
- Regenerative Engineering Laboratory, Columbia University Medical Center, 630 W. 168th Street, VC12-230, NY 10032, New York
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29
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Boys AJ, Kunitake JA, Henak CR, Cohen I, Estroff LA, Bonassar LJ. Understanding the Stiff-to-Compliant Transition of the Meniscal Attachments by Spatial Correlation of Composition, Structure, and Mechanics. ACS APPLIED MATERIALS & INTERFACES 2019; 11:26559-26570. [PMID: 31267742 PMCID: PMC6680087 DOI: 10.1021/acsami.9b03595] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Recently, the scientific community has shown considerable interest in engineering tissues with organized compositional and structural gradients to mimic hard-to-soft tissue interfaces. This effort is hindered by an incomplete understanding of the construction of native tissue interfaces. In this work, we combined Raman microscopy and confocal elastography to map compositional, structural, and mechanical features across the stiff-to-compliant interface of the attachments of the meniscus in the knee. This study provides new insight into the methods by which biology mediates multiple orders of magnitude changes in stiffness over tens of microns. We identified how the nano- to mesoscale architecture mediates complex microscale transitional regions across the interface: two regions defined by chemical composition, five distinguished by structural features, and three mechanically distinct regions. We identified three major components that lead to a robust interface between a soft tissue and bone: mobile collagen fiber units, a continuous interfacial region, and a local stiffness gradient. This tissue architecture allows for large displacements of collagen fibers in the attachments, enabling meniscal movement without localizing strains to the soft tissue-to-bone interface. The interplay of these regions reveals a method relying on hierarchical structuring across multiple length scales to minimize stress concentrators between highly dissimilar materials. These insights inspire new design strategies for synthetic soft tissue-to-bone attachments and biomimetic material interfaces.
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Affiliation(s)
- Alexander J. Boys
- Department of Materials Science & Engineering, Cornell University, Ithaca, NY 14853
| | | | - Corinne R. Henak
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
| | - Itai Cohen
- Department of Physics, Cornell University, Ithaca, NY 14853
| | - Lara A. Estroff
- Department of Materials Science & Engineering, Cornell University, Ithaca, NY 14853
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853
| | - Lawrence J. Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
- Sibley School of Mechanical Engineering, Cornell University, Ithaca, NY 14853
- Corresponding Author:
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30
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Boys AJ, Zhou H, Harrod JB, McCorry MC, Estroff LA, Bonassar LJ. Top-down Fabrication of Spatially Controlled Mineral-Gradient Scaffolds for Interfacial Tissue Engineering. ACS Biomater Sci Eng 2019; 5:2988-2997. [PMID: 31211246 DOI: 10.1021/acsbiomaterials.9b00176] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Materials engineering can generally be divided into "bottom-up" and "top-down" approaches, where current state-of-the-art methodologies are bottom-up, relying on the advent of atomic-scale technologies. Applying bottom-up approaches to biological tissues is challenging due to the inherent complexity of these systems. Top-down methodologies provide many advantages over bottom-up approaches for biological tissues, given that some of the complexity is already built into the system. Here, we generate interfacial scaffolds by the spatially controlled removal of mineral content from trabecular bone using a chelating solution. We controlled the degree and location of the mineral interface, producing scaffolds that support cell growth, while maintaining the hierarchical structure of these tissues. We characterized the structural and compositional gradients across the scaffold using X-ray diffraction, microcomputed tomography (μCT), and Raman microscopy, revealing the presence of mineral gradients on the scale of 20 - 40 μm. Using these data, we generated a model showing the dependence of mineral removal as function of time in the chelating solution and initial bone morphology, specifically trabecular density. These scaffolds will be useful for interfacial tissue engineering, with application in the fields of orthopedics, developmental biology, and cancer metastasis to bone.
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Affiliation(s)
- Alexander J Boys
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY
| | - Hao Zhou
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY
| | - Jordan B Harrod
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY
| | | | - Lara A Estroff
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY.,Kavli Institute for Nanoscale Science at Cornell, Cornell University, Ithaca, NY
| | - Lawrence J Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY.,Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY
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Deymier AC, Schwartz AG, Cai Z, Daulton TL, Pasteris JD, Genin GM, Thomopoulos S. The multiscale structural and mechanical effects of mouse supraspinatus muscle unloading on the mature enthesis. Acta Biomater 2019; 83:302-313. [PMID: 30342287 DOI: 10.1016/j.actbio.2018.10.024] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 10/04/2018] [Accepted: 10/15/2018] [Indexed: 12/17/2022]
Abstract
The musculoskeletal system is sensitive to its loading environment; this is of particular concern under conditions such as disuse, paralysis, and extended-duration space flight. Although structural and mechanical changes to tendon and bone following paralysis and disuse are well understood, there is a pressing need to understand how this unloading affects the bone-tendon interface (enthesis); the location most prone to tears and injury. We therefore elucidated these effects of unloading in the entheses of adult mice shoulders that were paralyzed for 21 days by treatment with botulinum toxin A. Unloading significantly increased the extent of mechanical failure and was associated with structural changes across hierarchical scales. At the millimeter scale, unloading caused bone loss. At the micrometer scale, unloading decreased bioapatite crystal size and crystallographic alignment in the enthesis. At the nanometer scale, unloading induced compositional changes that stiffened the bioapatite/collagen composite tissue. Mathematical modeling and mechanical testing indicated that these factors combined to increase local elevations of stress while decreasing the ability of the tissue to absorb energy prior to failure, thereby increasing injury risk. These first observations of the multiscale effects of unloading on the adult enthesis provide new insight into the hierarchical features of structure and composition that endow the enthesis with increased resistance to failure. STATEMENT OF SIGNIFICANCE: The musculoskeletal system is sensitive to its loading environment; this is of particular concern under conditions such as disuse, paralysis, and extended-duration space flight. Although changes to tendon and bone following paralysis are understood, there is a pressing need to clarify how unloading affects the bone-tendon interface (enthesis), which is the location most prone to tears and injury. We elucidated the effects of enthesis unloading in adult mice shoulders showing, for the first time, that unloading significantly increased the risk and extent of mechanical failure and was associated with structural changes across hierarchical scales. These observations provide new insight into the hierarchical features of structure and composition that endow the enthesis with resilience. This knowledge can be used to develop more targeted treatments to improve mobility and function.
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Affiliation(s)
- Alix C Deymier
- Department of Biomedical Engineering, University of Connecticut, Farmington, CT, USA.
| | - Andrea G Schwartz
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, USA.
| | - Zhounghou Cai
- Advanced Photon Source, Argonne National Lab, Argonne, IL, USA.
| | - Tyrone L Daulton
- Department of Physics, Washington University, St. Louis, MO, USA; Institute of Materials Science and Engineering, Washington University, St. Louis, MO, USA.
| | - Jill D Pasteris
- Department of Earth and Planetary Science, Washington University, St. Louis, MO, USA.
| | - Guy M Genin
- Department of Mechanical Engineering and Materials Science, Washington University, St. Louis, MO, USA.
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Columbia University, New York, NY, USA; Department of Biomedical Engineering, Columbia University, New York, NY, USA.
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Karakostis FA, Vlachodimitropoulos D, Piagkou M, Scherf H, Harvati K, Moraitis K. Is Bone Elevation in Hand Muscle Attachments Associated with Biomechanical Stress? A Histological Approach to an Anthropological Question. Anat Rec (Hoboken) 2018; 302:1093-1103. [DOI: 10.1002/ar.23984] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 06/09/2018] [Accepted: 06/18/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Fotios Alexandros Karakostis
- Paleoanthropology, Senckenberg Centre for Human Evolution and Paleoenvironment; University of Tübingen; Tübingen Germany
| | - Dimitrios Vlachodimitropoulos
- Department of Forensic Medicine and Toxicology, School of Medicine; National and Kapodistrian University of Athens; Athens Greece
| | - Maria Piagkou
- Department of Anatomy, School of Medicine; National and Kapodistrian University of Athens; Athens Greece
| | - Heike Scherf
- Paleoanthropology, Senckenberg Centre for Human Evolution and Paleoenvironment; University of Tübingen; Tübingen Germany
| | - Katerina Harvati
- Paleoanthropology, Senckenberg Centre for Human Evolution and Paleoenvironment; University of Tübingen; Tübingen Germany
- DFG Centre for Advanced Studies “Words, Bones, Genes, Tools: Tracking linguistic, cultural and biological trajectories of the human past”; University of Tübingen; Tübingen Germany
| | - Konstantinos Moraitis
- Department of Forensic Medicine and Toxicology, School of Medicine; National and Kapodistrian University of Athens; Athens Greece
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Karakostis FA, Hotz G, Tourloukis V, Harvati K. Evidence for precision grasping in Neandertal daily activities. SCIENCE ADVANCES 2018; 4:eaat2369. [PMID: 30263956 PMCID: PMC6157967 DOI: 10.1126/sciadv.aat2369] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 08/10/2018] [Indexed: 06/08/2023]
Abstract
Neandertal manual activities, as previously reconstructed from their robust hand skeletons, are thought to involve systematic power grasping rather than precise hand movements. However, this interpretation is at odds with increasing archeological evidence for sophisticated cultural behavior. We reevaluate the manipulative behaviors of Neandertals and early modern humans using a historical reference sample with extensive genealogical and lifelong occupational documentation, in combination with a new and precise three-dimensional multivariate analysis of hand muscle attachments. Results show that Neandertal muscle marking patterns overlap exclusively with documented lifelong precision workers, reflecting systematic precision grasping consistent with the use of their associated cultural remains. Our findings challenge the established interpretation of Neandertal behavior and establish a solid link between biological and cultural remains in the fossil record.
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Affiliation(s)
- Fotios Alexandros Karakostis
- Paleoanthropology, Senckenberg Centre for Human Evolution and Palaeoenvironment, Department of Geosciences, University of Tübingen, Tübingen 72070, Germany
| | - Gerhard Hotz
- Anthropological Collection, Natural History Museum of Basel, Basel 4051, Switzerland
- Integrative Prehistory and Archaeological Science, University of Basel, Basel 4055, Switzerland
| | - Vangelis Tourloukis
- Paleoanthropology, Senckenberg Centre for Human Evolution and Palaeoenvironment, Department of Geosciences, University of Tübingen, Tübingen 72070, Germany
- DFG (Deutsche Forschungsgemeinschaft) Center for Advanced Studies “Words, Bones, Genes, Tools,” Eberhard Karls University of Tübingen, Rümelinstrasse 23, D-72070 Tübingen, Germany
| | - Katerina Harvati
- Paleoanthropology, Senckenberg Centre for Human Evolution and Palaeoenvironment, Department of Geosciences, University of Tübingen, Tübingen 72070, Germany
- DFG (Deutsche Forschungsgemeinschaft) Center for Advanced Studies “Words, Bones, Genes, Tools,” Eberhard Karls University of Tübingen, Rümelinstrasse 23, D-72070 Tübingen, Germany
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Derwin KA, Galatz LM, Ratcliffe A, Thomopoulos S. Enthesis Repair: Challenges and Opportunities for Effective Tendon-to-Bone Healing. J Bone Joint Surg Am 2018; 100:e109. [PMID: 30106830 PMCID: PMC6133216 DOI: 10.2106/jbjs.18.00200] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
On May 22, 2017, the National Institutes of Health (NIH)/National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) hosted a roundtable on "Innovative Treatments for Enthesis Repair." A summary of the roundtable discussion, as well as a list of the extramural participants, can be found at https://www.niams.nih.gov/about/meetings-events/roundtables/roundtable-innovative-treatments-enthesis-repair. This paper reviews the challenges and opportunities for developing effective treatment strategies for enthesis repair that were identified at the roundtable discussion.
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Affiliation(s)
- Kathleen A. Derwin
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio,E-mail address for K.A. Derwin:
| | - Leesa M. Galatz
- Department of Orthopedic Surgery, Icahn School of Medicine at Mount Sinai, New York, NY
| | | | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Department of Biomedical Engineering, Columbia University, New York, NY
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35
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Locke RC, Peloquin JM, Lemmon EA, Szostek A, Elliott DM, Killian ML. Strain Distribution of Intact Rat Rotator Cuff Tendon-to-Bone Attachments and Attachments With Defects. J Biomech Eng 2018; 139:2657103. [PMID: 28979985 DOI: 10.1115/1.4038111] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Indexed: 12/28/2022]
Abstract
This study aimed to experimentally track the tissue-scale strains of the tendon-bone attachment with and without a localized defect. We hypothesized that attachments with a localized defect would develop strain concentrations and would be weaker than intact attachments. Uniaxial tensile tests and digital image correlation were performed on rat infraspinatus tendon-to-bone attachments with defects (defect group) and without defects (intact group). Biomechanical properties were calculated, and tissue-scale strain distributions were quantified for superior and inferior fibrous and calcified regions. At the macroscale, the defect group exhibited reduced stiffness (31.3±3.7 N/mm), reduced ultimate load (24.7±3.8 N), and reduced area under the curve at ultimate stress (3.7±1.5 J/m2) compared to intact attachments (42.4±4.3 N/mm, 39.3±3.7 N, and 5.6±1.4 J/m2, respectively). Transverse strain increased with increasing axial load in the fibrous region of the defect group but did not change for the intact group. Shear strain of the superior fibrous region was significantly higher in the defect group compared to intact group near yield load. This work experimentally identified that attachments may resist failure by distributing strain across the interface and that strain concentrations develop near attachment defects. By establishing the tissue-scale deformation patterns of the attachment, we gained insight into the micromechanical behavior of this interfacial tissue and bolstered our understanding of the deformation mechanisms associated with its ability to resist failure.
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Affiliation(s)
- Ryan C Locke
- Department of Biomedical Engineering, University of Delaware, 5 Innovation Way, Newark, DE 19716 e-mail:
| | - John M Peloquin
- Department of Biomedical Engineering, University of Delaware, 161 Colburn Lab 150 Academy Street, Newark, DE 19716 e-mail:
| | - Elisabeth A Lemmon
- Departments of Animal and Food Sciences and Biomedical Engineering, University of Delaware, 5 Innovation Way, Newark, DE 19716 e-mail:
| | - Adrianna Szostek
- Departments of Animal and Food Sciences and Biomedical Engineering, University of Delaware, 5 Innovation Way, Newark, DE 19716 e-mail:
| | - Dawn M Elliott
- Mem. ASME Department of Biomedical Engineering, University of Delaware, 161 Colburn Lab 150 Academy Street, Newark, DE 19716 e-mail:
| | - Megan L Killian
- Mem. ASME Department of Biomedical Engineering, University of Delaware, 5 Innovation Way, Newark, DE 19716 e-mail:
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Zhu C, Pongkitwitoon S, Qiu J, Thomopoulos S, Xia Y. Design and Fabrication of a Hierarchically Structured Scaffold for Tendon-to-Bone Repair. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1707306. [PMID: 29534316 PMCID: PMC6130203 DOI: 10.1002/adma.201707306] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/19/2018] [Indexed: 05/25/2023]
Abstract
A hierarchically structured scaffold is designed and fabricated for facilitating tendon-to-bone repair. The scaffold is composed of three regions with distinct functions: (i) an array of channels to guide the in-growth of cells and aligned deposition of collagen fibers, as well as integration of the scaffold with the tendon side, (ii) a region with a gradient in mineral composition to facilitate stress transfer between tendon and bone, and (iii) a mineralized inverse opal region to promote the integration of the scaffold with the underlying bone. Cell culture experiments confirm that adipose-derived stromal cells are able to infiltrate and proliferate through the entire thickness of the scaffold without compromised cell viability. The seeded stem cells exhibit directed differentiation into tenocytes and osteoblasts along the mineral gradient as a response to the gradient in Young's modulus. This novel scaffold holds great promise to promote the formation of a functional tendon-to-bone attachment by offering a structurally and compositionally appropriate microenvironment for healing.
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Affiliation(s)
- Chunlei Zhu
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA
| | | | - Jichuan Qiu
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA
| | - Stavros Thomopoulos
- Department of Orthopaedic Surgery, Columbia University, New York, NY, 10032, USA
- Department of Biomedical Engineering, Columbia University, New York, NY, 10027, USA
| | - Younan Xia
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA
- School of Chemistry and Biochemistry, School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
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37
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Karakostis FA, Hotz G, Scherf H, Wahl J, Harvati K. A repeatable geometric morphometric approach to the analysis of hand entheseal three-dimensional form. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:246-260. [DOI: 10.1002/ajpa.23421] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 11/29/2017] [Accepted: 01/12/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Fotios Alexandros Karakostis
- Paleoanthropology, Senckenberg Centre for Human Evolution and Paleoenvironment; University of Tübingen; Tübingen 72070 Germany
| | - Gerhard Hotz
- Anthropology section; Natural History Museum of Basel; Basel 4021 Switzerland
| | - Heike Scherf
- Paleoanthropology, Senckenberg Centre for Human Evolution and Paleoenvironment; University of Tübingen; Tübingen 72070 Germany
| | - Joachim Wahl
- Paleoanthropology, Senckenberg Centre for Human Evolution and Paleoenvironment; University of Tübingen; Tübingen 72070 Germany
- Osteology, State Office for Cultural Heritage Management Baden-Wu¨rttemberg; Konstanz 78467 Germany
| | - Katerina Harvati
- Paleoanthropology, Senckenberg Centre for Human Evolution and Paleoenvironment; University of Tübingen; Tübingen 72070 Germany
- DFG Centre for Advanced Studies “Words, Bones, Genes, Tools: Tracking linguistic, cultural and biological trajectories of the human past”; Institute of Archaeological Sciences, University of Tübingen; Tübingen 72070 Germany
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38
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Boys AJ, McCorry MC, Rodeo S, Bonassar LJ, Estroff LA. Next Generation Tissue Engineering of Orthopedic Soft Tissue-to-Bone Interfaces. MRS COMMUNICATIONS 2017; 7:289-308. [PMID: 29333332 PMCID: PMC5761353 DOI: 10.1557/mrc.2017.91] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 08/28/2017] [Indexed: 05/17/2023]
Abstract
Soft tissue-to-bone interfaces are complex structures that consist of gradients of extracellular matrix materials, cell phenotypes, and biochemical signals. These interfaces, called entheses for ligaments, tendons, and the meniscus, are crucial to joint function, transferring mechanical loads and stabilizing orthopedic joints. When injuries occur to connected soft tissue, the enthesis must be re-established to restore function, but due to structural complexity, repair has proven challenging. Tissue engineering offers a promising solution for regenerating these tissues. This prospective review discusses methodologies for tissue engineering the enthesis, outlined in three key design inputs: materials processing methods, cellular contributions, and biochemical factors.
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Affiliation(s)
- Alexander J Boys
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY
| | | | - Scott Rodeo
- Orthopedic Surgery, Hospital for Special Surgery, New York, NY
- Sports Medicine and Shoulder Service, Hospital for Special Surgery, New York, NY
- Tissue Engineering, Regeneration, and Repair Program, Hospital for Special Surgery, New York, NY
- Orthopedic Surgery, Weill Medical College of Cornell University, Cornell University, New York, NY
- New York Giants, East Rutherford, NJ
- Department of Orthopedic Surgery, Hospital for Special Surgery, New York, NY
| | - Lawrence J Bonassar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY
| | - Lara A Estroff
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY
- Kavli Institute at Cornell, Cornell University, Ithaca, NY
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39
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Deymier AC, An Y, Boyle JJ, Schwartz AG, Birman V, Genin GM, Thomopoulos S, Barber AH. Micro-mechanical properties of the tendon-to-bone attachment. Acta Biomater 2017; 56:25-35. [PMID: 28088669 DOI: 10.1016/j.actbio.2017.01.037] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 12/14/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
The tendon-to-bone attachment (enthesis) is a complex hierarchical tissue that connects stiff bone to compliant tendon. The attachment site at the micrometer scale exhibits gradients in mineral content and collagen orientation, which likely act to minimize stress concentrations. The physiological micromechanics of the attachment thus define resultant performance, but difficulties in sample preparation and mechanical testing at this scale have restricted understanding of structure-mechanical function. Here, microscale beams from entheses of wild type mice and mice with mineral defects were prepared using cryo-focused ion beam milling and pulled to failure using a modified atomic force microscopy system. Micromechanical behavior of tendon-to-bone structures, including elastic modulus, strength, resilience, and toughness, were obtained. Results demonstrated considerably higher mechanical performance at the micrometer length scale compared to the millimeter tissue length scale, describing enthesis material properties without the influence of higher order structural effects such as defects. Micromechanical investigation revealed a decrease in strength in entheses with mineral defects. To further examine structure-mechanical function relationships, local deformation behavior along the tendon-to-bone attachment was determined using local image correlation. A high compliance zone near the mineralized gradient of the attachment was clearly identified and highlighted the lack of correlation between mineral distribution and strain on the low-mineral end of the attachment. This compliant region is proposed to act as an energy absorbing component, limiting catastrophic failure within the tendon-to-bone attachment through higher local deformation. This understanding of tendon-to-bone micromechanics demonstrates the critical role of micrometer scale features in the mechanics of the tissue. STATEMENT OF SIGNIFICANCE The tendon-to-bone attachment (enthesis) is a complex hierarchical tissue with features at a numerous scales that dissipate stress concentrations between compliant tendon and stiff bone. At the micrometer scale, the enthesis exhibits gradients in collagen and mineral composition and organization. However, the physiological mechanics of the enthesis at this scale remained unknown due to difficulty in preparing and testing micrometer scale samples. This study is the first to measure the tensile mechanical properties of the enthesis at the micrometer scale. Results demonstrated considerably enhanced mechanical performance at the micrometer length scale compared to the millimeter tissue length scale and identified a high-compliance zone near the mineralized gradient of the attachment. This understanding of tendon-to-bone micromechanics demonstrates the critical role of micrometer scale features in the mechanics of the tissue.
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Rossetti L, Kuntz LA, Kunold E, Schock J, Müller KW, Grabmayr H, Stolberg-Stolberg J, Pfeiffer F, Sieber SA, Burgkart R, Bausch AR. The microstructure and micromechanics of the tendon-bone insertion. NATURE MATERIALS 2017; 16:664-670. [PMID: 28250445 DOI: 10.1038/nmat4863] [Citation(s) in RCA: 172] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 01/17/2017] [Indexed: 05/28/2023]
Abstract
The exceptional mechanical properties of the load-bearing connection of tendon to bone rely on an intricate interplay of its biomolecular composition, microstructure and micromechanics. Here we identify that the Achilles tendon-bone insertion is characterized by an interface region of ∼500 μm with a distinct fibre organization and biomolecular composition. Within this region, we identify a heterogeneous mechanical response by micromechanical testing coupled with multiscale confocal microscopy. This leads to localized strains that can be larger than the remotely applied strain. The subset of fibres that sustain the majority of loading in the interface area changes with the angle of force application. Proteomic analysis detects enrichment of 22 proteins in the interfacial region that are predominantly involved in cartilage and skeletal development as well as proteoglycan metabolism. The presented mechanisms mark a guideline for further biomimetic strategies to rationally design hard-soft interfaces.
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Affiliation(s)
- L Rossetti
- Lehrstuhl für Zellbiophysik, Technische Universität München, D-85748 Garching, Germany
| | - L A Kuntz
- Lehrstuhl für Zellbiophysik, Technische Universität München, D-85748 Garching, Germany
- Klinik für Orthopädie und Sportorthopädie, Klinikum rechts der Isar, Technische Universität München, D-81675 München, Germany
| | - E Kunold
- Center for Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, D-85747 Garching, Germany
| | - J Schock
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, D-85748 Garching, Germany
| | - K W Müller
- Institute for Computational Mechanics, Technische Universität München, D-85748 Garching, Germany
- Structural and Applied Mechanics Group, Computational Engineering Division, Lawrence Livermore National Laboratory, 7000 East Ave, Livermore, California 94550, USA
| | - H Grabmayr
- Lehrstuhl für Zellbiophysik, Technische Universität München, D-85748 Garching, Germany
- Department of Physics and Center for Nanoscience, Ludwig Maximilian University, D-80539 Munich, Germany
| | - J Stolberg-Stolberg
- Klinik für Orthopädie und Sportorthopädie, Klinikum rechts der Isar, Technische Universität München, D-81675 München, Germany
- University Hospital Münster, Department of Trauma-, Hand- and Reconstructive Surgery, Albert-Schweitzer-Campus 1, Building W1, D-48149 Münster, Germany
| | - F Pfeiffer
- Lehrstuhl für Biomedizinische Physik, Physik-Department &Institut für Medizintechnik, Technische Universität München, D-85748 Garching, Germany
- Institut für diagnostische und interventionelle Radiologie, Klinikum rechts der Isar, Technische Universität München, D-81675 München, Germany
| | - S A Sieber
- Center for Integrated Protein Science (CIPSM), Department of Chemistry, Technische Universität München, D-85747 Garching, Germany
| | - R Burgkart
- Klinik für Orthopädie und Sportorthopädie, Klinikum rechts der Isar, Technische Universität München, D-81675 München, Germany
| | - A R Bausch
- Lehrstuhl für Zellbiophysik, Technische Universität München, D-85748 Garching, Germany
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Genin GM, Thomopoulos S. The tendon-to-bone attachment: Unification through disarray. NATURE MATERIALS 2017; 16:607-608. [PMID: 28541313 PMCID: PMC5575797 DOI: 10.1038/nmat4906] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
High-resolution imaging, composition analysis and mechanical testing reveal a disordered transitional material within the Achilles tendon-to-bone attachment, structured as a fibrous network to enable force transfer and maximize structural integrity.
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Affiliation(s)
- Guy M Genin
- Bioinspired Engineering and Biomechanics Center (BEBC), the Key Laboratory of Biomedical Information Engineering, Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China, and the Department of Mechanical Engineering and Materials Science, School of Engineering and Applied Science, and the Department of Neurological Surgery at Washington University in St Louis, Missouri 63130, USA
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, and the Department of Biomedical Engineering at Columbia University, New York 10032, USA
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42
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The concentration of stress at the rotator cuff tendon-to-bone attachment site is conserved across species. J Mech Behav Biomed Mater 2016; 62:24-32. [PMID: 27161959 DOI: 10.1016/j.jmbbm.2016.04.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Revised: 04/13/2016] [Accepted: 04/15/2016] [Indexed: 01/03/2023]
Abstract
The tendon-to-bone attachment site integrates two distinct tissues via a gradual transition in composition, mechanical properties, and structure. Outcomes of surgical repair are poor, in part because surgical repair does not recreate the natural attachment, and in part because the mechanical features that are most critical to mechanical and physiological functions have not been identified. We employed allometric analysis to resolve a paradox about how the architecture of the rotator cuff contributes to load transfer: whereas published data suggest that the mean muscle stresses expected at the tendon-to-bone attachment are conserved across species, data also show that the relative dimensions of key anatomical features vary dramatically, suggesting that the amplification of stresses at the interface between tendon and bone should also vary widely. However, a mechanical model that enabled a sensitivity analysis revealed that the degree of stress concentration was in fact highly conserved across species: the factors that most affected stress amplification were most highly conserved across species, while those that had a lower effect showed broad variation across a range of relative insensitivity. Results highlight how micromechanical factors can influence structure-function relationships and cross-species scaling over several orders of magnitude in animal size, and provide guidance on physiological features to emphasize in surgical and tissue engineered repair of the rotator cuff.
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