1
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Peifer C, Oláh T, Venkatesan JK, Goebel L, Orth P, Schmitt G, Zurakowski D, Menger MD, Laschke MW, Cucchiarini M, Madry H. Locally Directed Recombinant Adeno- Associated Virus-Mediated IGF-1 Gene Therapy Enhances Osteochondral Repair and Counteracts Early Osteoarthritis In Vivo. Am J Sports Med 2024; 52:1336-1349. [PMID: 38482805 DOI: 10.1177/03635465241235149] [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] [Indexed: 04/04/2024]
Abstract
BACKGROUND Restoration of osteochondral defects is critical, because osteoarthritis (OA) can arise. HYPOTHESIS Overexpression of insulin-like growth factor 1 (IGF-1) via recombinant adeno-associated viral (rAAV) vectors (rAAV-IGF-1) would improve osteochondral repair and reduce parameters of early perifocal OA in sheep after 6 months in vivo. STUDY DESIGN Controlled laboratory study. METHODS Osteochondral defects were created in the femoral trochlea of adult sheep and treated with rAAV-IGF-1 or rAAV-lacZ (control) (24 defects in 6 knees per group). After 6 months in vivo, osteochondral repair and perifocal OA were assessed by well-established macroscopic, histological, and immunohistochemical scoring systems as well as biochemical and micro-computed tomography evaluations. RESULTS Application of rAAV-IGF-1 led to prolonged (6 months) IGF-1 overexpression without adverse effects, maintaining a significantly superior overall cartilage repair, together with significantly improved defect filling, extracellular matrix staining, cellular morphology, and surface architecture compared with rAAV-lacZ. Expression of type II collagen significantly increased and that of type I collagen significantly decreased. Subchondral bone repair and tidemark formation were significantly improved, and subchondral bone plate thickness and subarticular spongiosa mineral density returned to normal. The OA parameters of perifocal structure, cell cloning, and matrix staining were significantly better preserved upon rAAV-IGF-1 compared with rAAV-lacZ. Novel mechanistic associations between parameters of osteochondral repair and OA were identified. CONCLUSION Local rAAV-mediated IGF-1 overexpression enhanced osteochondral repair and ameliorated parameters of perifocal early OA. CLINICAL RELEVANCE IGF-1 gene therapy may be beneficial in repair of focal osteochondral defects and prevention of perifocal OA.
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Affiliation(s)
- Carolin Peifer
- Center of Experimental Orthopaedics, Saarland University, Homburg/Saar, Germany
| | - Tamás Oláh
- Center of Experimental Orthopaedics, Saarland University, Homburg/Saar, Germany
| | | | - Lars Goebel
- Center of Experimental Orthopaedics, Saarland University, Homburg/Saar, Germany
| | - Patrick Orth
- Center of Experimental Orthopaedics, Saarland University, Homburg/Saar, Germany
| | - Gertrud Schmitt
- Center of Experimental Orthopaedics, Saarland University, Homburg/Saar, Germany
| | - David Zurakowski
- Departments of Anesthesia and Surgery, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts, USA
| | - Michael D Menger
- Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar, Germany
| | - Matthias W Laschke
- Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar, Germany
| | - Magali Cucchiarini
- Center of Experimental Orthopaedics, Saarland University, Homburg/Saar, Germany
| | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University, Homburg/Saar, Germany
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2
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Changoor A, Suderman RP, Alshaygy I, Fuhrmann A, Akens MK, Safir O, Grynpas MD, Kuzyk PRT. Irregular porous titanium enhances implant stability and bone ingrowth in an intra-articular ovine model. J Orthop Res 2022; 40:2294-2307. [PMID: 35146795 DOI: 10.1002/jor.25272] [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: 03/31/2021] [Revised: 12/02/2021] [Accepted: 01/16/2022] [Indexed: 02/04/2023]
Abstract
Two commercially available porous coatings, Gription and Porocoat, were compared for the first time in a challenging intra-articular, weight-bearing, ovine model. Gription has evolved from Porocoat and has higher porosity, coefficient of friction, and microtextured topography, which are expected to enhance bone ingrowth. Cylindrical implants were press-fit into the weight-bearing regions of ovine femoral condyles and bone ingrowth and fixation strength evaluated 4, 8, and 16 weeks postoperatively. Biomechanical push-out tests were performed on lateral femoral condyles (LFCs) to evaluate the strength of the bone-implant interface. Bone ingrowth was assessed in medial femoral condyles (MFCs) as well as implants retrieved from LFCs following biomechanical testing using backscattered electron microscopy and histology. By 16 weeks, Gription-coated implants exhibited higher force (2455 ± 1362 vs. 1002 ± 1466 N; p = 0.046) and stress (12.60 ± 6.99 vs. 5.14 ± 7.53 MPa; p = 0.046) at failure, and trended towards higher stiffness (11,510 ± 7645 vs. 5010 ± 8374 N/mm; p = 0.061) and modulus of elasticity (591 ± 392 vs. 256 ± 431 MPa; p = 0.061). A strong, positive correlation was detected between bone ingrowth in LFC implants and failure force (r = 0.93, p < 10-13 ). By 16 weeks, bone ingrowth in Gription-coated implants in MFCs was 10.50 ± 6.31% compared to 5.88 ± 2.77% in Porocoat (p = 0.095). Observations of the bone-implant interface, made following push-out testing, showed more bony material consistently adhered to Gription compared to Porocoat at all three time points. Gription provided superior fixation strength and bone ingrowth by 16 weeks.
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Affiliation(s)
- Adele Changoor
- Department of Surgery and Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Lunenfeld Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada
| | - R Peter Suderman
- Department of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Ibrahim Alshaygy
- Division of Orthopaedic Surgery, King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia.,Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Ariel Fuhrmann
- Department of Surgery, University of Toronto, Toronto, Ontario, Canada.,Department of Orthopedic Surgery, Barzilai Medical Centre, Ashkelon, Israel
| | - Margarete K Akens
- Department of Surgery and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.,Techna Institute, University Health Network, Toronto, Ontario, Canada
| | - Oleg Safir
- Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Marc D Grynpas
- Lunenfeld Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada.,Department of Laboratory Medicine & Pathobiology and Department of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Paul R T Kuzyk
- Department of Surgery, University of Toronto, Toronto, Ontario, Canada
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3
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Nordberg RC, Otarola GA, Wang D, Hu JC, Athanasiou KA. Navigating regulatory pathways for translation of biologic cartilage repair products. Sci Transl Med 2022; 14:eabp8163. [PMID: 36001677 PMCID: PMC9918326 DOI: 10.1126/scitranslmed.abp8163] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Long-term clinical repair of articular cartilage remains elusive despite advances in cartilage tissue engineering. Only one cartilage repair therapy classified as a "cellular and gene therapy product" has obtained Food and Drug Administration (FDA) approval within the past decade although more than 200 large animal cartilage repair studies were published. Here, we identify the challenges impeding translation of strategies and technologies for cell-based cartilage repair, such as the disconnect between university funding and regulatory requirements. Understanding the barriers to translation and developing solutions to address them will be critical for advancing cell therapy products for cartilage repair to clinical use.
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Affiliation(s)
- Rachel C Nordberg
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697 USA
| | - Gaston A Otarola
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697 USA
| | - Dean Wang
- Department of Orthopaedic Surgery, University of California Irvine Medical Center, Orange, CA 92868, USA
| | - Jerry C Hu
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697 USA
| | - Kyriacos A Athanasiou
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697 USA
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4
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Stachel N, Orth P, Zurakowski D, Menger MD, Laschke MW, Cucchiarini M, Madry H. Subchondral Drilling Independent of Drill Hole Number Improves Articular Cartilage Repair and Reduces Subchondral Bone Alterations Compared With Debridement in Adult Sheep. Am J Sports Med 2022; 50:2669-2679. [PMID: 35834876 DOI: 10.1177/03635465221104775] [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] [Indexed: 01/31/2023]
Abstract
BACKGROUND Subchondral drilling is an established marrow stimulation technique for small cartilage defects, but whether drilling is required at all and if the drill hole density affects repair remains unclear. HYPOTHESES Osteochondral repair is improved when the subchondral bone is perforated by a higher number of drill holes per unit area, and drilling is superior to defect debridement alone. STUDY DESIGN Controlled laboratory study. METHODS Rectangular full-thickness chondral defects (4 × 8 mm) were created in the trochlea of adult sheep (N = 16), debrided down to the subchondral bone plate without further treatment as controls (no treatment; n = 7) or treated with either 2 or 6 (n = 7 each) subchondral drill holes (diameter, 1.0 mm; depth, 10.0 mm). Osteochondral repair was assessed at 6 months postoperatively by standardized (semi-)quantitative macroscopic, histological, immunohistochemical, biochemical, and micro-computed tomography analyses. RESULTS Compared with defect debridement alone, histological overall cartilaginous repair tissue quality (P = .025) and the macroscopic aspect of the adjacent cartilage (P≤ .032) were improved after both drilling densities. Only drilling with 6 holes increased type 2 collagen content in the repair tissue compared with controls (P = .038). After debridement, bone mineral density was significantly decreased in the subchondral bone plate (P≤ .015) and the subarticular spongiosa (P≤ .041) compared with both drilling groups. Debridement also significantly increased intralesional osteophyte sectional area compared with drilling (P≤ .034). No other differences in osteochondral repair existed between subchondral drilling with 6 or 2 drill holes. CONCLUSION Subchondral drilling independent of drill hole density significantly improves structural cartilage repair compared with sole defect debridement of full-thickness cartilage defects in sheep after 6 months. Subchondral drilling also leads to a better reconstitution of the subchondral bone compartment below the defects. Simultaneously, drilling reduced the formation of intralesional osteophytes caused by osseous overgrowth compared with debridement. CLINICAL RELEVANCE These results have important clinical implications, as they support subchondral drilling independent of drill hole number but discourage debridement alone for the treatment of small cartilage defects. Clinical studies are warranted to further quantify the effects of subchondral drilling in similar settings.
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Affiliation(s)
- Niklas Stachel
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Patrick Orth
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - David Zurakowski
- Departments of Anesthesia and Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Michael D Menger
- Institute for Clinical and Experimental Surgery, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Matthias W Laschke
- Institute for Clinical and Experimental Surgery, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Magali Cucchiarini
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
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5
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Ribitsch I, Bileck A, Egerbacher M, Gabner S, Mayer RL, Janker L, Gerner C, Jenner F. Fetal Immunomodulatory Environment Following Cartilage Injury-The Key to CARTILAGE Regeneration? Int J Mol Sci 2021; 22:ijms222312969. [PMID: 34884768 PMCID: PMC8657887 DOI: 10.3390/ijms222312969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 11/27/2021] [Accepted: 11/28/2021] [Indexed: 01/15/2023] Open
Abstract
Fetal cartilage fully regenerates following injury, while in adult mammals cartilage injury leads to osteoarthritis (OA). Thus, in this study, we compared the in vivo injury response of fetal and adult ovine articular cartilage histologically and proteomically to identify key factors of fetal regeneration. In addition, we compared the secretome of fetal ovine mesenchymal stem cells (MSCs) in vitro with injured fetal cartilage to identify potential MSC-derived therapeutic factors. Cartilage injury caused massive cellular changes in the synovial membrane, with macrophages dominating the fetal, and neutrophils the adult, synovial cellular infiltrate. Correspondingly, proteomics revealed differential regulation of pro- and anti-inflammatory mediators and growth-factors between adult and fetal joints. Neutrophil-related proteins and acute phase proteins were the two major upregulated protein groups in adult compared to fetal cartilage following injury. In contrast, several immunomodulating proteins and growth factors were expressed significantly higher in the fetus than the adult. Comparison of the in vitro MSCs proteome with the in vivo fetal regenerative signature revealed shared upregulation of 17 proteins, suggesting their therapeutic potential. Biomimicry of the fetal paracrine signature to reprogram macrophages and modulate inflammation could be an important future research direction for developing novel therapeutics.
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Affiliation(s)
- Iris Ribitsch
- VETERM, Equine Surgery Unit, Department of Companion Animals and Horses, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;
| | - Andrea Bileck
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria; (A.B.); (R.L.M.); (L.J.)
| | - Monika Egerbacher
- Administrative Unit Veterinary Medicine, UMIT—Private University for Health Sciences, Medical Informatics and Technology GmbH, 6060 Hall in Tirol, Austria;
| | - Simone Gabner
- Histology & Embryology, Department of Pathobiology, University of Veterinary Medicine, 1210 Vienna, Austria;
| | - Rupert L. Mayer
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria; (A.B.); (R.L.M.); (L.J.)
| | - Lukas Janker
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria; (A.B.); (R.L.M.); (L.J.)
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria; (A.B.); (R.L.M.); (L.J.)
- Correspondence: (C.G.); (F.J.)
| | - Florien Jenner
- VETERM, Equine Surgery Unit, Department of Companion Animals and Horses, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;
- Correspondence: (C.G.); (F.J.)
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6
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Lange C, Madry H, Venkatesan JK, Schmitt G, Speicher-Mentges S, Zurakowski D, Menger MD, Laschke MW, Cucchiarini M. rAAV-Mediated sox9 Overexpression Improves the Repair of Osteochondral Defects in a Clinically Relevant Large Animal Model Over Time In Vivo and Reduces Perifocal Osteoarthritic Changes. Am J Sports Med 2021; 49:3696-3707. [PMID: 34643471 DOI: 10.1177/03635465211049414] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Gene transfer of the transcription factor SOX9 with clinically adapted recombinant adeno-associated virus (rAAV) vectors offers a powerful tool to durably enhance the repair process at sites of osteochondral injuries and counteract the development of perifocal osteoarthritis (OA) in the adjacent articular cartilage. PURPOSE To examine the ability of an rAAV sox9 construct to improve the repair of focal osteochondral defects and oppose perifocal OA development over time in a large translational model relative to control gene transfer. STUDY DESIGN Controlled laboratory study. METHODS Standardized osteochondral defects created in the knee joints of adult sheep were treated with rAAV-FLAG-hsox9 relative to control (reporter) rAAV-lacZ gene transfer. Osteochondral repair and degenerative changes in the adjacent cartilage were monitored using macroscopic, histological, immunohistological, and biochemical evaluations after 6 months. The microarchitecture of the subchondral bone was assessed by micro-computed tomography. RESULTS Effective, prolonged sox9 overexpression via rAAV was significantly achieved in the defects after 6 months versus rAAV-lacZ treatment. The application of rAAV-FLAG-hsox9 improved the individual parameters of defect filling, matrix staining, cellular morphology, defect architecture, surface architecture, subchondral bone, and tidemark as well as the overall score of cartilage repair in the defects compared with rAAV-lacZ. The overexpression of sox9 led to higher levels of proteoglycan production, stronger type II collagen deposition, and reduced type I collagen immunoreactivity in the sox9- versus lacZ-treated defects, together with decreased cell densities and DNA content. rAAV-FLAG-hsox9 enhanced semiquantitative histological subchondral bone repair, while the microstructure of the incompletely restored subchondral bone in the sox9 defects was not different from that in the lacZ defects. The articular cartilage adjacent to the sox9-treated defects showed reduced histological signs of perifocal OA changes versus rAAV-lacZ. CONCLUSION rAAV-mediated sox9 gene transfer enhanced osteochondral repair in sheep after 6 months and reduced perifocal OA changes. These results underline the potential of rAAV-FLAG-hsox9 as a therapeutic tool to treat cartilage defects and afford protection against OA. CLINICAL RELEVANCE The delivery of therapeutic rAAV sox9 to sites of focal injuries may offer a novel, convenient tool to enhance the repair of osteochondral defects involving both the articular cartilage and the underlying subchondral bone and provide a protective role by reducing the extent of perifocal OA.
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Affiliation(s)
- Cliff Lange
- Center of Experimental Orthopaedics, Saarland University Medical Center, Homburg, Germany
| | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University Medical Center, Homburg, Germany
| | - Jagadeesh K Venkatesan
- Center of Experimental Orthopaedics, Saarland University Medical Center, Homburg, Germany
| | - Gertrud Schmitt
- Center of Experimental Orthopaedics, Saarland University Medical Center, Homburg, Germany
| | | | - David Zurakowski
- Departments of Anesthesia and Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Michael D Menger
- Institute for Clinical and Experimental Surgery, Saarland University, Homburg, Germany
| | - Matthias W Laschke
- Institute for Clinical and Experimental Surgery, Saarland University, Homburg, Germany
| | - Magali Cucchiarini
- Center of Experimental Orthopaedics, Saarland University Medical Center, Homburg, Germany
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7
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van Hugten PPW, Jeuken RM, Roth AK, Seeldrayers S, Emans PJ. An optimized medial parapatellar approach to the goat medial femoral condyle. Animal Model Exp Med 2021; 4:54-58. [PMID: 33738437 PMCID: PMC7954842 DOI: 10.1002/ame2.12150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 12/16/2020] [Indexed: 11/12/2022] Open
Abstract
Goats or sheep are the preferred animal model for the preclinical evaluation of cartilage repair techniques due to the similarity of the goat stifle joint to the human knee. The medial femoral condyle of the stifle joint is the preferred site for the assessment of articular cartilage repair, as this is the primary location for this type of lesion in the human knee. Proper surgical exposure of the medial femoral condyle is paramount to obtain reproducible results without surgical error. When applying the standard human medial arthrotomy technique on the goat stifle joint, there are some key aspects to consider in order to prevent destabilization of the extensor apparatus and subsequent postoperative patellar dislocations with associated animal discomfort. This paper describes a modified surgical technique to approach the medial femoral condyle of the caprine stifle joint. The modified technique led to satisfactory exposure without postoperative incidence of patellar luxations and no long-term adverse effects on the joint.
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Affiliation(s)
- Pieter P. W. van Hugten
- Laboratory for Experimental OrthopedicsDepartment of Orthopedic SurgeryMaastricht University Medical CenterMaastrichtThe Netherlands
| | - Ralph M. Jeuken
- Laboratory for Experimental OrthopedicsDepartment of Orthopedic SurgeryMaastricht University Medical CenterMaastrichtThe Netherlands
| | - Alex K. Roth
- Laboratory for Experimental OrthopedicsDepartment of Orthopedic SurgeryMaastricht University Medical CenterMaastrichtThe Netherlands
| | - Saskia Seeldrayers
- Laboratory Animal FacilityMaastricht UniversityMaastrichtThe Netherlands
| | - Peter J. Emans
- Laboratory for Experimental OrthopedicsDepartment of Orthopedic SurgeryMaastricht University Medical CenterMaastrichtThe Netherlands
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8
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Morscheid YP, Venkatesan JK, Schmitt G, Orth P, Zurakowski D, Speicher-Mentges S, Menger MD, Laschke MW, Cucchiarini M, Madry H. rAAV-Mediated Human FGF-2 Gene Therapy Enhances Osteochondral Repair in a Clinically Relevant Large Animal Model Over Time In Vivo. Am J Sports Med 2021; 49:958-969. [PMID: 33606561 DOI: 10.1177/0363546521988941] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Osteochondral defects, if left untreated, do not heal and can potentially progress toward osteoarthritis. Direct gene transfer of basic fibroblast growth factor 2 (FGF-2) with the clinically adapted recombinant adeno-associated viral (rAAV) vectors is a powerful tool to durably activate osteochondral repair processes. PURPOSE To examine the ability of an rAAV-FGF-2 construct to target the healing processes of focal osteochondral injury over time in a large translational model in vivo versus a control gene transfer condition. STUDY DESIGN Controlled laboratory study. METHODS Standardized osteochondral defects created in the knee joints of adult sheep were treated with an rAAV human FGF-2 (hFGF-2) vector by direct administration into the defect relative to control (reporter) rAAV-lacZ gene transfer. Osteochondral repair was monitored using macroscopic, histological, immunohistological, and biochemical methods and by micro-computed tomography after 6 months. RESULTS Effective, localized prolonged FGF-2 overexpression was achieved for 6 months in vivo relative to the control condition without undesirable leakage of the vectors outside the defects. Such rAAV-mediated hFGF-2 overexpression significantly increased the individual histological parameter "percentage of new subchondral bone" versus lacZ treatment, reflected in a volume of mineralized bone per unit volume of the subchondral bone plate that was equal to a normal osteochondral unit. Also, rAAV-FGF-2 significantly improved the individual histological parameters "defect filling,""matrix staining," and "cellular morphology" and the overall cartilage repair score versus the lacZ treatment and led to significantly higher cell densities and significantly higher type II collagen deposition versus lacZ treatment. Likewise, rAAV-FGF-2 significantly decreased type I collagen expression within the cartilaginous repair tissue. CONCLUSION The current work shows the potential of direct rAAV-mediated FGF-2 gene therapy to enhance osteochondral repair in a large, clinically relevant animal model over time in vivo. CLINICAL RELEVANCE Delivery of therapeutic (hFGF-2) rAAV vectors in sites of focal injury may offer novel, convenient tools to enhance osteochondral repair in the near future.
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Affiliation(s)
- Yannik P Morscheid
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Jagadeesh K Venkatesan
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Gertrud Schmitt
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Patrick Orth
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - David Zurakowski
- Department of Anesthesiology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Susanne Speicher-Mentges
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Michael D Menger
- Institute for Clinical and Experimental Surgery, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Matthias W Laschke
- Institute for Clinical and Experimental Surgery, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Magali Cucchiarini
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
| | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University Medical Center and Saarland University, Homburg/Saar, Germany
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9
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Oláh T, Cai X, Michaelis JC, Madry H. Comparative anatomy and morphology of the knee in translational models for articular cartilage disorders. Part I: Large animals. Ann Anat 2021; 235:151680. [PMID: 33548412 DOI: 10.1016/j.aanat.2021.151680] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/08/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND The human knee is a complex joint, and affected by a variety of articular cartilage disorders. Large animal models are critical to model the complex disease mechanisms affecting a functional joint. Species-dependent differences highly affect the results of a pre-clinical study and need to be considered, necessitating specific knowledge not only of macroscopic and microscopic anatomical and pathological aspects, but also characteristics of their individual gait and joint movements. METHODS Literature search in Pubmed. RESULTS AND DISCUSSION This narrative review summarizes the most relevant anatomical structural and functional characteristics of the knee (stifle) joints of the major translational large animal species, comprising dogs, (mini)pigs, sheep, goats, and horses in comparison with humans. Specific characteristics of each species, including kinematical gait parameters are provided. Considering these multifactorial dimensions will allow to select the appropriate model for answering the research questions in a clinically relevant fashion.
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Affiliation(s)
- Tamás Oláh
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany
| | - Xiaoyu Cai
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany
| | | | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany; Department of Orthopaedic Surgery, Saarland University Medical Center, Homburg, Germany.
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10
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Wang D, Cubberly M, Brown WE, Kwon H, Hu JC, Athanasiou KA. Diagnostic Arthroscopy of the Minipig Stifle (Knee) for Translational Large Animal Research. Arthrosc Tech 2021; 10:e297-e301. [PMID: 33680759 PMCID: PMC7917015 DOI: 10.1016/j.eats.2020.10.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 10/08/2020] [Indexed: 02/03/2023] Open
Abstract
To gain regulatory approval for the clinical use of knee biologics and devices in humans, translational large-animal studies are typically required. Animal models that permit second-look arthroscopy are valuable because they allow for longitudinal assessment of the treated tissue without needing to sacrifice the animal. The minipig is an ideal preclinical animal model for the investigation of therapies for the knee, in part because arthroscopy can be performed in its stifle (knee) joint with the use of standard surgical equipment used in humans. The purpose of this Technical Note is to describe a reproducible technique for diagnostic arthroscopy of the minipig stifle (knee) joint.
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Affiliation(s)
- Dean Wang
- Department of Orthopaedic Surgery, University of California Irvine, Irvine, California, U.S.A.,Address correspondence to Dean Wang, M.D., Department of Orthopaedic Surgery, UCI Health, 101 The City Dr S, Pav III, Orange, CA 92868, U.S.A.
| | - Mark Cubberly
- Department of Orthopaedic Surgery, University of California Irvine, Irvine, California, U.S.A
| | - Wendy E. Brown
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, U.S.A
| | - Heenam Kwon
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, U.S.A
| | - Jerry C. Hu
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, U.S.A
| | - Kyriacos A. Athanasiou
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, U.S.A
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11
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Systematic Postoperative Assessment of a Minimally-Invasive Sheep Model for the Treatment of Osteochondral Defects. Life (Basel) 2020; 10:life10120332. [PMID: 33297497 PMCID: PMC7762399 DOI: 10.3390/life10120332] [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: 11/09/2020] [Revised: 12/01/2020] [Accepted: 12/04/2020] [Indexed: 11/26/2022] Open
Abstract
To assess the clinical course of a sheep stifle joint model for osteochondral (OC) defects, medial femoral condyles (MFC) were exposed without patella luxation using medial parapatellar skin (3–4 cm) and deep incisions (2–3 cm). Two defects (7 mm diameter; 10 mm depth; OC punch) were left empty or refilled with osteochondral autologous transplantation cylinders (OATS) and explanted after six weeks. Incision-to-suture time, anesthesia time, and postoperative wound or impairment scores were compared to those in sham-operated animals. Implant performance was assessed by X-ray, micro-computed tomography, histology, and immunohistology (collagens 1, 2; aggrecan). There were no surgery-related infections or patellar luxations. Operation, anesthesia, and time to complete stand were short (0.5, 1.4, and 1.5 h, respectively). The wound trauma score was low (0.4 of maximally 4; day 7). Empty-defect and OATS animals reached an impairment score of 0 significantly later than sham animals (7.4 and 4.0 days, respectively, versus 1.5 days). Empty defects showed incomplete healing and dedifferentiation/heterotopic differentiation; OATS-filled defects displayed advanced bone healing with remaining cartilage gaps and orthotopic expression of bone and cartilage markers. Minimally-invasive, medial parapatellar surgery of OC defects on the sheep MFC allows rapid and low-trauma recovery and appears well-suited for implant testing.
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12
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Flynn C, Hurtig M, Lamoure E, Cummins E, Roati V, Lowerison M, Jeong SY, Oh W, Zur Linden A. Modeling and Staging of Osteoarthritis Progression Using Serial CT Imaging and Arthroscopy. Cartilage 2020; 11:338-347. [PMID: 30079757 PMCID: PMC7298601 DOI: 10.1177/1947603518789997] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE The objective of this study was to describe in life methods by which osteoarthritis can be staged in order to time therapeutic interventions that are relevant to osteoarthritis (OA) clinical trials. METHODS Twenty-two sheep underwent arthroscopic meniscal destabilization to induce OA. Serial computed tomography (CT) imaging and arthroscopy were used to monitor osteoarthritis progression at 3-month intervals over 9 months. Eleven sheep received 1 intra-articular injection of hyaluronate 3 months after OA induction and another group of 11 received saline. A linear mixed model was used to define the trajectory of shape change in the medial joint compartment. Ordinal logistic regression was used to investigate the association between morphological changes and sclerosis. RESULTS Three months after meniscal destabilization there were early bipolar chondral lesions in the medial compartment of the knee, as well as osteophytes and bone remodeling. Superficial fissures and cartilage cracks progressed to discrete areas of cartilage thinning and fibrillation on the medial tibial plateau by 6 months that became cartilage erosions by nine months. A linear mixed effect model demonstrated significant change in medial compartment length and width with over time (P < 0.05) for both groups. A significant association between severity of sclerosis and medial compartment morphology was also observed. CONCLUSIONS The induction of osteoarthritic lesions with meniscal release model can be followed using noninvasive and minimally invasive procedures allowing for real-time decisions about redosing therapies, or other changes such as extending trial timelines without sacrificing animals to conduct assessments.
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Affiliation(s)
- Candace Flynn
- Department of Clinical Studies, Ontario
Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Mark Hurtig
- Department of Clinical Studies, Ontario
Veterinary College, University of Guelph, Guelph, Ontario, Canada,Mark Hurtig, Comparative Orthopaedic
Research, Department of Clinical Studies, Ontario Veterinary College, University
of Guelph, 50 McGilvray Street, Guelph, Ontario, N1G 2W1, Canada.
| | - Emma Lamoure
- Department of Clinical Studies, Ontario
Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Erin Cummins
- Department of Clinical Studies, Ontario
Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Valeria Roati
- Department of Clinical Studies, Ontario
Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Mark Lowerison
- Clinical Research Unit, University of
Calgary, Calgary, Alberta, Canada
| | | | - Wonil Oh
- MEDIPOST Co., Ltd., Seoul, Republic of
Korea
| | - Alex Zur Linden
- Department of Clinical Studies, Ontario
Veterinary College, University of Guelph, Guelph, Ontario, Canada
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13
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Small-Diameter Subchondral Drilling Improves DNA and Proteoglycan Content of the Cartilaginous Repair Tissue in a Large Animal Model of a Full-Thickness Chondral Defect. J Clin Med 2020; 9:jcm9061903. [PMID: 32570841 PMCID: PMC7356183 DOI: 10.3390/jcm9061903] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 06/16/2020] [Indexed: 01/02/2023] Open
Abstract
This study quantified changes in the DNA content and extracellular matrix composition of both the cartilaginous repair tissue and the adjacent cartilage in a large animal model of a chondral defect treated by subchondral drilling. Content of DNA, proteoglycans, and Type II and Type I collagen, as well as their different ratios were assessed at 6 months in vivo after treatment of full-thickness cartilage defects in the femoral trochlea of adult sheep with six subchondral drill holes, each of either 1.0 mm or 1.8 mm in diameter by biochemical analyses of the repair tissue and the adjacent cartilage and compared with the original cartilage. Only subchondral drilling which were 1.0 mm in diameter significantly increased both DNA and proteoglycan content of the repair tissue compared to the original cartilage. DNA content correlated with the proteoglycan and Type II collagen content within the repair tissue. Significantly higher amounts of Type I collagen within the repair tissue and significantly increased DNA, proteoglycan, and Type I collagen content in the adjacent cartilage were identified. These translational data support the use of small-diameter bone-cutting devices for marrow stimulation. Signs of early degeneration were present within the cartilaginous repair tissue and the adjacent cartilage.
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14
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Friedman JM, Sennett ML, Bonadio MB, Orji KO, Neuwirth AL, Keah N, Carey JL, Moutos FT, Estes BT, Guilak F, Madry H, Mauck RL, Dodge GR. Comparison of Fixation Techniques of 3D-Woven Poly(ϵ-Caprolactone) Scaffolds for Cartilage Repair in a Weightbearing Porcine Large Animal Model. Cartilage 2018; 9:428-437. [PMID: 28397530 PMCID: PMC6139593 DOI: 10.1177/1947603517700953] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Objective To test different fixation methods of a 3-dimensionally woven poly(ϵ-caprolactone) (PCL) scaffold within chondral defects of a weightbearing large animal model. Methods Full thickness chondral defects were made in the femoral condyles of 15 adult male Yucatan mini-pigs. Two surgical approaches were compared including total arthrotomy (traditional) and a retinaculum-sparing, minimally invasive surgery (MIS) approach. Following microfracture (MFX), scaffolds were placed without fixation or were fixed with fibrin glue, suture, or subchondral anchor. Experimental endpoints were between 1 and 6 weeks. Micro-computed tomography and histology were used to assess samples. Results The MIS approach was superior as the traditional approach caused medial condyle cartilage wear. One of 13 (7.7%) of scaffolds without fixation, 4 of 11 (36.3%) fibrin scaffolds, 1 of 4 (25%) of sutured scaffolds, and 9 of 9 (100%) of anchor-fixed scaffolds remained in place. Histology demonstrated tissue filling with some overgrowth of PCL scaffolds. Conclusions Of the methods tested, the MIS approach coupled with subchondral anchor fixation provided the best scaffold retention in a mini-pig chondral defect model. This finding has implications for fixation strategies in future animal studies and potential future human use.
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Affiliation(s)
- James M. Friedman
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research
Center, Philadelphia VA Medical Center, Philadelphia, PA, USA
| | - Mackenzie L. Sennett
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research
Center, Philadelphia VA Medical Center, Philadelphia, PA, USA
| | - Marcelo B. Bonadio
- Department of Orthopedic Surgery,
University of São Paulo, São Paulo, Brazil
| | - Kerry O. Orji
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA
| | - Alexander L. Neuwirth
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA
| | - Niobra Keah
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA
| | - James L. Carey
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - Farshid Guilak
- Cytex Therapeutics, Durham, NC,
USA,Department of Orthopaedic Surgery,
Washington University in St. Louis and Shriners Hospitals for Children–St. Louis,
St. Louis, MO, USA,Collaborative Research Partnership–Acute
Cartilage Injury Program, AO Foundation, Davos, Switzerland
| | - Henning Madry
- Department of Orthopaedic Surgery,
Saarland University Medical Center, Homberg/Saar, Germany,Collaborative Research Partnership–Acute
Cartilage Injury Program, AO Foundation, Davos, Switzerland
| | - Robert L. Mauck
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research
Center, Philadelphia VA Medical Center, Philadelphia, PA, USA,Collaborative Research Partnership–Acute
Cartilage Injury Program, AO Foundation, Davos, Switzerland
| | - George R. Dodge
- Department of Orthopaedic Surgery, McKay
Orthopaedic Research Lab, University of Pennsylvania, Philadelphia, PA, USA,Translational Musculoskeletal Research
Center, Philadelphia VA Medical Center, Philadelphia, PA, USA,Collaborative Research Partnership–Acute
Cartilage Injury Program, AO Foundation, Davos, Switzerland,George R. Dodge, Department of Orthopaedic
Surgery, McKay Orthopaedic Research Lab, University of Pennsylvania, 424
Stemmler Hall, 36th Street & Hamilton Walk, Philadelphia, PA 19104, USA.
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15
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Ribitsch I, Mayer RL, Egerbacher M, Gabner S, Kańduła MM, Rosser J, Haltmayer E, Auer U, Gültekin S, Huber J, Bileck A, Kreil DP, Gerner C, Jenner F. Fetal articular cartilage regeneration versus adult fibrocartilaginous repair: secretome proteomics unravels molecular mechanisms in an ovine model. Dis Model Mech 2018; 11:11/7/dmm033092. [PMID: 29991479 PMCID: PMC6078409 DOI: 10.1242/dmm.033092] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 05/18/2018] [Indexed: 12/27/2022] Open
Abstract
Osteoarthritis (OA), a degenerative joint disease characterized by progressive cartilage degeneration, is one of the leading causes of disability worldwide owing to the limited regenerative capacity of adult articular cartilage. Currently, there are no disease-modifying pharmacological or surgical therapies for OA. Fetal mammals, in contrast to adults, are capable of regenerating injured cartilage in the first two trimesters of gestation. A deeper understanding of the properties intrinsic to the response of fetal tissue to injury would allow us to modulate the way in which adult tissue responds to injury. In this study, we employed secretome proteomics to compare fetal and adult protein regulation in response to cartilage injury using an ovine cartilage defect model. The most relevant events comprised proteins associated with the immune response and inflammation, proteins specific for cartilage tissue and cartilage development, and proteins involved in cell growth and proliferation. Alarmins S100A8, S100A9 and S100A12 and coiled-coil domain containing 88A (CCDC88A), which are associated with inflammatory processes, were found to be significantly upregulated following injury in adult, but not in fetal animals. By contrast, cartilage-specific proteins like proteoglycan 4 were upregulated in response to injury only in fetal sheep postinjury. Our results demonstrate the power and relevance of the ovine fetal cartilage regeneration model presented here for the first time. The identification of previously unrecognized modulatory proteins that plausibly affect the healing process holds great promise for potential therapeutic interventions. Summary: Secretome proteomics identifies differential regulation of inflammation modulators during fetal and adult articular cartilage defect healing, offering novel strategies for therapy.
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Affiliation(s)
- Iris Ribitsch
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Rupert L Mayer
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna 1090, Austria
| | - Monika Egerbacher
- Histology & Embryology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Simone Gabner
- Histology & Embryology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Maciej M Kańduła
- Department of Biotechnology, Boku University Vienna, Vienna 1180, Austria.,Institute of Bioinformatics, Johannes Kepler University, Linz 4040, Austria
| | - Julie Rosser
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Eva Haltmayer
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Ulrike Auer
- Department of Companion Animals and Horses, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Sinan Gültekin
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Johann Huber
- Teaching and Research Farm Kremesberg, Clinical Unit for Herd Health Management in Ruminants, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna 1210, Austria
| | - Andrea Bileck
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna 1090, Austria
| | - David P Kreil
- Department of Biotechnology, Boku University Vienna, Vienna 1180, Austria
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna 1090, Austria
| | - Florien Jenner
- VETERM, University Equine Hospital, University of Veterinary Medicine Vienna, Vienna 1210, Austria
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16
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Rogatko CP, Warnock JJ, Bobe G, Verpaalen VD. Comparison of iatrogenic articular cartilage injury in canine stifle arthroscopy versus medial parapatellar mini-arthrotomy in a cadaveric model. Vet Surg 2017; 47:O6-O14. [DOI: 10.1111/vsu.12736] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 06/13/2017] [Accepted: 07/06/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Cleo P. Rogatko
- Department of Clinical Sciences, College of Veterinary Medicine; Oregon State University; Corvallis Oregon
| | - Jennifer J. Warnock
- Department of Clinical Sciences, College of Veterinary Medicine; Oregon State University; Corvallis Oregon
| | - Gerd Bobe
- Department of Rangeland Sciences and The Linus Pauling Institute; Oregon State University; Corvallis Oregon
| | - Valentine D. Verpaalen
- Department of Clinical Sciences, College of Veterinary Medicine; Oregon State University; Corvallis Oregon
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17
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Bansal S, Keah NM, Neuwirth AL, O'Reilly O, Qu F, Seiber BN, Mandalapu S, Mauck RL, Zgonis MH. Large Animal Models of Meniscus Repair and Regeneration: A Systematic Review of the State of the Field. Tissue Eng Part C Methods 2017. [PMID: 28622089 DOI: 10.1089/ten.tec.2017.0080] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Injury to the meniscus is common, but few viable strategies exist for its repair or regeneration. To address this, animal models have been developed to translate new treatment strategies toward the clinic. However, there is not yet a regulatory document guiding such studies. The purpose of this study was to carry out a systematic review of the literature on meniscus treatment methods and outcomes to define the state of the field. Public databases were queried by using search terms related to animal models and meniscus injury and/or repair over the years 1980-2015. Identified peer-reviewed manuscripts were screened by using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. One of nine reviewers read each manuscript and scored them based on whether the publication described a series of predefined study descriptors and outcome measures. Additional data were extracted to identify common assays used. A total of 128 full-length peer-reviewed manuscripts were identified. The number of publications increased over the time frame analyzed, with 48% focused on augmented repair. Rabbit was, by far, the most prevalent species utilized (46%), with dog (21%) and sheep (20%) being the next most common. Analysis of study descriptors revealed that most studies appropriately documented details of the animal used, the surgical approach, and defect and implant characteristics (e.g., 63% of studies identified clearly the defect size). In terms of outcome parameters, most studies carried out macroscopic (85%), histologic (90%), and healing/integration (83%) analyses of the meniscus. However, many studies did not provide further analysis beyond these fundamental measures, and less than 40% reported on the adjacent cartilage and synovium, as well as joint function. There is intense interest in the field of meniscus repair. However, given the current lack of guidance documentation in this area, preclinical animal models are not performed in a standardized fashion. The development of a "Best Practices" document would increase reproducibility and external validity of experiments, while accelerating advancements in translational research. Advancement is of paramount importance given the high prevalence of meniscal injuries and the paucity of effective repair or regenerative strategies.
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Affiliation(s)
- Sonia Bansal
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania.,2 Department of Bioengineering, University of Pennsylvania , Philadelphia, Pennsylvania.,3 Translational Musculoskeletal Research Center, Philadelphia Veterans Administration Medical Center , Philadelphia, Pennsylvania
| | - Niobra M Keah
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania.,3 Translational Musculoskeletal Research Center, Philadelphia Veterans Administration Medical Center , Philadelphia, Pennsylvania
| | - Alexander L Neuwirth
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania.,3 Translational Musculoskeletal Research Center, Philadelphia Veterans Administration Medical Center , Philadelphia, Pennsylvania
| | - Olivia O'Reilly
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
| | - Feini Qu
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania.,2 Department of Bioengineering, University of Pennsylvania , Philadelphia, Pennsylvania.,3 Translational Musculoskeletal Research Center, Philadelphia Veterans Administration Medical Center , Philadelphia, Pennsylvania
| | - Breanna N Seiber
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania.,3 Translational Musculoskeletal Research Center, Philadelphia Veterans Administration Medical Center , Philadelphia, Pennsylvania
| | - Sai Mandalapu
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
| | - Robert L Mauck
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania.,2 Department of Bioengineering, University of Pennsylvania , Philadelphia, Pennsylvania.,3 Translational Musculoskeletal Research Center, Philadelphia Veterans Administration Medical Center , Philadelphia, Pennsylvania
| | - Miltiadis H Zgonis
- 1 McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
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18
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Bonadio MB, Friedman JM, Sennett ML, Mauck RL, Dodge GR, Madry H. A retinaculum-sparing surgical approach preserves porcine stifle joint cartilage in an experimental animal model of cartilage repair. J Exp Orthop 2017; 4:11. [PMID: 28417444 PMCID: PMC5393980 DOI: 10.1186/s40634-017-0083-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 03/16/2017] [Indexed: 12/19/2022] Open
Abstract
Background This study compares a traditional parapatellar retinaculum-sacrificing arthrotomy to a retinaculum-sparing arthrotomy in a porcine stifle joint as a cartilage repair model. Findings Surgical exposure of the femoral trochlea of ten Yucatan pigs stifle joint was performed using either a traditional medial parapatellar approach with retinaculum incision and luxation of the patella (n = 5) or a minimally invasive (MIS) approach which spared the patellar retinaculum (n = 5). Both classical and MIS approaches provided adequate access to the trochlea, enabling the creation of cartilage defects without difficulties. Four full thickness, 4 mm circular full-thickness cartilage defects were created in each trochlea. There were no intraoperative complications observed in either surgical approach. All pigs were allowed full weight-bearing and full range of motion immediately postoperatively and were euthanized between 2 and 3 weeks. The traditional approach was associated with increased cartilage wear compared to the MIS approach. Two blinded raters performed gross evaluation of the trochlea cartilage surrounding the defects according to the modified ICRS cartilage injury classification. The traditional approach cartilage received a significantly worse score than the MIS approach group from both scorers (3.2 vs 0.8, p = 0.01 and 2.8 vs 0, p = 0.005 respectively). Conclusion The MIS approach results in less damage to the trochlear cartilage and faster return to load bearing activities. As an arthrotomy approach in the porcine model, MIS is superior to the traditional approach.
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Affiliation(s)
- Marcelo B Bonadio
- Department of Orthopedic Surgery, University of São Paulo, São Paulo, Brazil
| | - James M Friedman
- McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA
| | - Mackenzie L Sennett
- McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert L Mauck
- McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA.,Collaborative Research Partnership - Acute Cartilage Injury Program, AO Foundation, Davos, Switzerland
| | - George R Dodge
- McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA.,Collaborative Research Partnership - Acute Cartilage Injury Program, AO Foundation, Davos, Switzerland
| | - Henning Madry
- Department of Orthopaedic Surgery, Saarland University Medical Center, Homberg, Saar, Germany. .,Collaborative Research Partnership - Acute Cartilage Injury Program, AO Foundation, Davos, Switzerland.
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19
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Orth P, Duffner J, Zurakowski D, Cucchiarini M, Madry H. Small-Diameter Awls Improve Articular Cartilage Repair After Microfracture Treatment in a Translational Animal Model. Am J Sports Med 2016; 44:209-19. [PMID: 26546301 DOI: 10.1177/0363546515610507] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Microfracture is the most commonly applied arthroscopic marrow stimulation procedure. HYPOTHESIS Articular cartilage repair is improved when the subchondral bone is perforated by small-diameter microfracture awls compared with larger awls. STUDY DESIGN Controlled laboratory study. METHODS Standardized rectangular (4 × 8 mm) full-thickness chondral defects (N = 24) were created in the medial femoral condyle of 16 adult sheep and debrided down to the subchondral bone plate. Three treatment groups (n = 8 defects each) were tested: 6 microfracture perforations using small-diameter awls (1.0 mm; group 1), large-diameter awls (1.2 mm; group 2), or without perforations (debridement control; group 3). Osteochondral repair was assessed at 6 months in vivo using established macroscopic, histological, immunohistochemical, biochemical, and micro-computed tomography analyses. RESULTS Compared with control defects, histological cartilage repair was always improved after both microfracture techniques (P < .023). Application of 1.0-mm microfracture awls led to a significantly improved histological overall repair tissue quality (7.02 ± 0.70 vs 9.03 ± 0.69; P = .008) and surface grading (1.05 ± 0.28 vs 2.10 ± 0.19; P = .001) compared with larger awls. The small-diameter awl decreased relative bone volume of the subarticular spongiosa (bone volume/tissue volume ratio: 23.81% ± 3.37% vs 30.58% ± 2.46%; P = .011). Subchondral bone cysts and intralesional osteophytes were frequently observed after either microfracture treatment. Macroscopic grading, DNA, proteoglycan, and type I and type II collagen contents as well as degenerative changes within the adjacent cartilage remained unaffected by the awl diameter. CONCLUSION Small-diameter microfracture awls improve articular cartilage repair in the translational sheep model more effectively than do larger awls. CLINICAL RELEVANCE These data support the use of small microfracture instruments for the surgical treatment of cartilage defects and warrant prolonged clinical investigations.
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Affiliation(s)
- Patrick Orth
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany Department of Orthopaedic Surgery, Saarland University Medical Center, Homburg, Germany
| | - Julia Duffner
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany
| | - David Zurakowski
- Departments of Anesthesia and Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Magali Cucchiarini
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany
| | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany Department of Orthopaedic Surgery, Saarland University Medical Center, Homburg, Germany
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20
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Goebel L, Müller A, Bücker A, Madry H. High resolution MRI imaging at 9.4 Tesla of the osteochondral unit in a translational model of articular cartilage repair. BMC Musculoskelet Disord 2015; 16:91. [PMID: 25888208 PMCID: PMC4404065 DOI: 10.1186/s12891-015-0543-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 03/27/2015] [Indexed: 12/13/2022] Open
Abstract
Background Non-destructive structural evaluation of the osteochondral unit is challenging. Here, the capability of high-field magnetic resonance imaging (μMRI) at 9.4 Tesla (T) was explored to examine osteochondral repair ex vivo in a preclinical large animal model. A specific aim of this study was to detect recently described alterations of the subchondral bone associated with cartilage repair. Methods Osteochondral samples of medial femoral condyles from adult ewes containing full-thickness articular cartilage defects treated with marrow stimulation were obtained after 6 month in vivo and scanned in a 9.4 T μMRI. Ex vivo imaging of small osteochondral samples (typical volume: 1–2 cm3) at μMRI was optimised by variation of repetition time (TR), time echo (TE), flip angle (FA), spatial resolution and number of excitations (NEX) from standard MultiSliceMultiEcho (MSME) and three-dimensional (3D) spoiled GradientEcho (SGE) sequences. Results A 3D SGE sequence with the parameters: TR = 10 ms, TE = 3 ms, FA = 10 °, voxel size = 120 × 120 × 120 μm3 and NEX = 10 resulted in the best fitting for sample size, image quality, scanning time and artifacts. An isovolumetric voxel shape allowed for multiplanar reconstructions. Within the osteochondral unit articular cartilage, cartilaginous repair tissue and bone marrow could clearly be distinguished from the subchondral bone plate and subarticular spongiosa. Specific alterations of the osteochondral unit associated with cartilage repair such as persistent drill holes, subchondral bone cysts, sclerosis of the subchondral bone plate and of the subarticular spongiosa and intralesional osteophytes were precisely detected. Conclusions High resolution, non-destructive ex vivo analysis of the entire osteochondral unit in a preclinical large animal model that is sufficient for further analyses is possible using μMRI at 9.4 T. In particular, 9.4 T is capable of accurately depicting alterations of the subchondral bone that are associated with osteochondral repair.
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Affiliation(s)
- Lars Goebel
- Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrberger Straße, Building 37, Homburg/Saar, D-66421, Germany. .,Department of Orthopaedic Surgery, Saarland University Medical Center, Kirrberger Straße, Building 37, Homburg/Saar, D-66421, Germany. .,Cartilage Net of the Greater Region, University of the Greater Region, Homburg/Saar, D-66421, Germany.
| | - Andreas Müller
- Department of Diagnostic and Interventional Radiology, Saarland University Medical Center, Kirrberger Straße, Building 57, Homburg/Saar, D-66421, Germany.
| | - Arno Bücker
- Department of Diagnostic and Interventional Radiology, Saarland University Medical Center, Kirrberger Straße, Building 57, Homburg/Saar, D-66421, Germany.
| | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University Medical Center, Kirrberger Straße, Building 37, Homburg/Saar, D-66421, Germany. .,Department of Orthopaedic Surgery, Saarland University Medical Center, Kirrberger Straße, Building 37, Homburg/Saar, D-66421, Germany. .,Cartilage Net of the Greater Region, University of the Greater Region, Homburg/Saar, D-66421, Germany.
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Goetzen M, Hofmann-Fliri L, Arens D, Zeiter S, Stadelmann V, Nehrbass D, Richards RG, Blauth M. Does metaphyseal cement augmentation in fracture management influence the adjacent subchondral bone and joint cartilage?: an in vivo study in sheep stifle joints. Medicine (Baltimore) 2015; 94:e414. [PMID: 25621690 PMCID: PMC4602635 DOI: 10.1097/md.0000000000000414] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Augmentation of implants with polymethylmethacrylate (PMMA) bone cement in osteoporotic fractures is a promising approach to increase implant purchase. Side effects of PMMA for the metaphyseal bone, particularly for the adjacent subchondral bone plate and joint cartilage, have not yet been studied. The following experimental study investigates whether subchondral PMMA injection compromises the homeostasis of the subchondral bone and/or the joint cartilage.Ten mature sheep were used to simulate subchondral PMMA injection. Follow-ups of 2 (4 animals) and 4 (6 animals) months were chosen to investigate possible cartilage damage and subchondral plate alterations in the knee. Evaluation was completed by means of high-resolution peripheral quantitative computed tomography (HRpQCT) imaging, histopathological osteoarthritis scoring, and determination of glycosaminoglycan content in the joint cartilage. Results were compared with the untreated contralateral knee and statistically analyzed using nonparametric tests.Evaluation of the histological osteoarthritis score revealed no obvious cartilage damage for the treated knee; median histological score after 2 months 0 (range 4), after 4 months 1 (range 5). There was no significant difference when compared with the untreated control site after 2 and 4 months (P = 0.23 and 0.76, respectively). HRpQCT imaging showed no damage to the metaphyseal trabeculae. Glycosaminoglycan measurements of the treated joint cartilage after 4 months revealed no significant difference compared with the untreated cartilage (P = 0.24).The findings of this study support initial clinical observation that PMMA implant augmentation of metaphyseal fractures appears to be a safe procedure for fixation without harming the subchondral bone plate and adjacent joint cartilage.
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Affiliation(s)
- Michael Goetzen
- From the AO Research Institute Davos (MG, L-HF, DA, SZ, VS, DN, GR), Davos, Switzerland; and Department of Trauma Surgery (MG, MB), Medical University of Innsbruck, Innsbruck, Austria
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Eldracher M, Orth P, Cucchiarini M, Pape D, Madry H. Small subchondral drill holes improve marrow stimulation of articular cartilage defects. Am J Sports Med 2014; 42:2741-50. [PMID: 25167994 DOI: 10.1177/0363546514547029] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Subchondral drilling is an established marrow stimulation technique. HYPOTHESIS Osteochondral repair is improved when the subchondral bone is perforated with small drill holes, reflecting the physiological subchondral trabecular distance. STUDY DESIGN Controlled laboratory study. METHODS A rectangular full-thickness chondral defect was created in the trochlea of adult sheep (n = 13) and treated with 6 subchondral drillings of either 1.0 mm (reflective of the trabecular distance) or 1.8 mm in diameter. Osteochondral repair was assessed after 6 months in vivo by macroscopic, histological, and immunohistochemical analyses and by micro-computed tomography. RESULTS The application of 1.0-mm subchondral drill holes led to significantly improved histological matrix staining, cellular morphological characteristics, subchondral bone reconstitution, and average total histological score as well as significantly higher immunoreactivity to type II collagen and reduced immunoreactivity to type I collagen in the repair tissue compared with 1.8-mm drill holes. Analysis of osteoarthritic changes in the cartilage adjacent to the defects revealed no significant differences between treatment groups. Restoration of the microstructure of the subchondral bone plate below the chondral defects was significantly improved after 1.0-mm compared to 1.8-mm drilling, as shown by higher bone volume and reduced thickening of the subchondral bone plate. Likewise, the microarchitecture of the drilled subarticular spongiosa was better restored after 1.0-mm drilling, indicated by significantly higher bone volume and more and thinner trabeculae. Moreover, the bone mineral density of the subchondral bone in 1.0-mm drill holes was similar to the adjacent subchondral bone, whereas it was significantly reduced in 1.8-mm drill holes. No significant correlations existed between cartilage and subchondral bone repair. CONCLUSION Small subchondral drill holes that reflect the physiological trabecular distance improve osteochondral repair in a translational model more effectively than larger drill holes. CLINICAL RELEVANCE These results have important implications for the use of subchondral drilling for marrow stimulation, as they support the use of small-diameter bone-cutting devices.
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Affiliation(s)
- Mona Eldracher
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany
| | - Patrick Orth
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany Department of Orthopaedic Surgery, Saarland University Medical Center, Homburg, Germany Cartilage Net of the Greater Region (Germany, France, Belgium, Luxembourg)
| | - Magali Cucchiarini
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany Cartilage Net of the Greater Region (Germany, France, Belgium, Luxembourg)
| | - Dietrich Pape
- Cartilage Net of the Greater Region (Germany, France, Belgium, Luxembourg) Olympic Medical Center, Centre Hospitalier de Luxembourg, Clinique d'Eich, Luxembourg, Luxembourg
| | - Henning Madry
- Center of Experimental Orthopaedics, Saarland University, Homburg, Germany Department of Orthopaedic Surgery, Saarland University Medical Center, Homburg, Germany Cartilage Net of the Greater Region (Germany, France, Belgium, Luxembourg)
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Arthroscopy of the normal cadaveric ovine femorotibial joint: a systematic approach to the cranial and caudal compartments. Vet Comp Orthop Traumatol 2014; 27:387-94. [PMID: 25213032 DOI: 10.3415/vcot-14-03-0039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Accepted: 07/13/2014] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Preclinical studies using large animal models play an intergral part in translational research. For this study, our objectives were: to develop and validate arthroscopic approaches to four compartments of the stifle joint as determined via the gross and arthroscopic anatomy of the cranial and caudal aspects of the joint. METHODS Cadaveric hindlimbs (n = 39) were harvested from mature ewes. The anatomy was examined by tissue dissection (n = 6), transverse sections (n = 4), and computed tomography (n = 4). The joint was arthroscopically explored in 25 hindlimbs. RESULTS A cranio-medial portal was created medial to the patellar ligament. The cranio-lateral portal was made medial to the extensor digitorum longus tendon. The medial femoral condyle was visible, as well as the cranial cruciate ligament, caudal cruciate ligament and both menisci with the intermeniscal ligament. Valgus stress improved visibility of the caudal horn of the medial meniscus and tibial plateau. To explore the caudal compartments, a portal was created 1 cm proximal to the most caudal aspect of the tibial condyle. Both femoral condyles, menisci, caudal cruciate ligament, the popliteal tendon and the menisco-femoral ligament were visible. The common peroneal nerve and popliteal artery and vein are vulnerable structures to injury during arthroscopy. CLINICAL SIGNIFICANCE The arthroscopic approach developed in this research is ideal to evaluate the ovine stifle joint.
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Orth P, Meyer HL, Goebel L, Eldracher M, Ong MF, Cucchiarini M, Madry H. Improved repair of chondral and osteochondral defects in the ovine trochlea compared with the medial condyle. J Orthop Res 2013; 31:1772-9. [PMID: 23813860 DOI: 10.1002/jor.22418] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Accepted: 06/05/2013] [Indexed: 02/04/2023]
Abstract
Associations between topographic location and articular cartilage repair in preclinical animal models are unknown. Based on clinical investigations, we hypothesized that lesions in the ovine femoral condyle repair better than in the trochlea. Full-thickness chondral and osteochondral defects were simultaneously established in the weightbearing area of the medial femoral condyle and the lateral trochlear facet in sheep, with chondral defects subjected to subchondral drilling. After 6 months in vivo, cartilage repair and osteoarthritis development was evaluated by macroscopic, histological, immunohistochemical, and biochemical analyses. Macroscopic and histological articular cartilage repair and type-II collagen immunoreactivity were better in the femoral trochlea, regardless of the defect type. Location-independently, osteochondral defects induced more osteoarthritic degeneration of the adjacent cartilage than drilled chondral lesions. DNA and proteoglycan contents of chondral defects were higher in the condyle, reflecting physiological topographical differences. The results indicate that topographic location dictates the structural patterns and biochemical composition of the repair tissue in sheep. These findings suggest that repair of cartilage defects at different anatomical sites of the ovine stifle joint needs to be assessed independently and that the sheep trochlea exhibits cartilage repair patterns reflective of the human medial femoral condyle.
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Affiliation(s)
- Patrick Orth
- Center of Experimental Orthopaedics, Saarland University, Building 37-38, D-66421, Homburg/Saar, Germany; Department of Orthopaedic Surgery, Saarland University Medical Center, Homburg/Saar, Germany
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