Topic:Articular Cartilage
Articular cartilage in horses is a specialized connective tissue found at the ends of bones within joints. It provides a smooth, lubricated surface for articulation and facilitates the transmission of loads with a low frictional coefficient. Articular cartilage is primarily composed of chondrocytes, collagen fibers, and proteoglycans, and it lacks blood vessels, nerves, and lymphatics. This avascular nature contributes to its limited capacity for self-repair following injury. The health and integrity of articular cartilage are essential for maintaining joint function and mobility in horses. This page compiles peer-reviewed research studies and scholarly articles that explore the structure, function, and pathological changes of articular cartilage in equine species, as well as advancements in diagnostic and therapeutic approaches for cartilage-related disorders.
Microstructural changes in cartilage and bone related to repetitive overloading in an equine athlete model. The palmar aspect of the third metacarpal (MC3) condyle of equine athletes is known to be subjected to repetitive overloading that can lead to the accumulation of joint tissue damage, degeneration, and stress fractures, some of which result in catastrophic failure. However, there is still a need to understand at a detailed microstructural level how this damage progresses in the context of the wider joint tissue complex, i.e. the articular surface, the hyaline and calcified cartilage, and the subchondral bone. MC3 bones from non-fractured joints were obtained from the right forelimbs of 16 Thor...
Effect of osmotic stress on the expression of TRPV4 and BKCa channels and possible interaction with ERK1/2 and p38 in cultured equine chondrocytes. The metabolic activity of articular chondrocytes is influenced by osmotic alterations that occur in articular cartilage secondary to mechanical load. The mechanisms that sense and transduce mechanical signals from cell swelling and initiate volume regulation are poorly understood. The purpose of this study was to investigate how the expression of two putative osmolyte channels [transient receptor potential vanilloid 4 (TRPV4) and large-conductance Ca(2+)-activated K(+) (BKCa)] in chondrocytes is modulated in different osmotic conditions and to examine a potential role for MAPKs in this process...
Osteochondral lesions in distal tarsal joints of Icelandic horses reveal strong associations between hyaline and calcified cartilage abnormalities. Osteochondral lesions in the joints of the distal tarsal region of young Icelandic horses provide a natural model for the early stages of osteoarthritis (OA) in low-motion joints. We describe and characterise mineralised and non-mineralised osteochondral lesions in left distal tarsal region joint specimens from twenty-two 30 ±1 month-old Icelandic horses. Combinations of confocal scanning light microscopy, backscattered electron scanning electron microscopy (including, importantly, iodine staining) and three-dimensional microcomputed tomography were used on specimens obtained with guidance f...
Effects of interleukin-6 and interleukin-1β on expression of growth differentiation factor-5 and Wnt signaling pathway genes in equine chondrocytes. To determine the effects of interleukin (IL)-6 and IL-1β stimulation on expression of growth differentiation factor (GDF)-5 and Wnt signaling pathway genes in equine chondrocytes. Methods: Macroscopically normal articular cartilage samples from 6 horses and osteochondral fragments (OCFs) from 3 horses. Methods: Chondrocyte pellets were prepared and cultured without stimulation or following stimulation with IL-6 or IL-1β for 1, 2, 12, and 48 hours; expression of GDF-5 was determined with a quantitative real-time PCR assay. Expression of genes in various signaling pathways was determined with ...
Clinical outcome after intra-articular administration of bone marrow derived mesenchymal stem cells in 33 horses with stifle injury. To report outcome of horses with femorotibial lesions (meniscal, cartilage or ligamentous) treated with surgery and intra-articular administration of autologous bone marrow derived mesenchymal stem cells (BMSCs). Methods: Prospective case series. Methods: Horses (n = 33). Methods: Inclusion criteria included horses that had lameness localized to the stifle by diagnostic anesthesia, exploratory stifle arthroscopy and subsequent intra-articular administration of autologous BMSCs. Case details and follow-up were gathered from medical records, owner, trainer or veterinarian. Outcome was defined as...
Carprofen inhibits the release of matrix metalloproteinases 1, 3, and 13 in the secretome of an explant model of articular cartilage stimulated with interleukin 1β. Arthritic diseases are characterized by the degradation of collagenous and noncollagenous extracellular matrix (ECM) components in articular cartilage. The increased expression and activity of matrix metalloproteinases (MMPs) is partly responsible for cartilage degradation. This study used proteomics to identify inflammatory proteins and catabolic enzymes released in a serum-free explant model of articular cartilage stimulated with the pro-inflammatory cytokine interleukin 1β (IL-1β). Western blotting was used to quantify the release of selected proteins in the presence or absence of the cyc...
Maintenance of arytenoid abduction following carbon dioxide laser debridement of the articular cartilage and joint capsule of the cricoarytenoid joint combined with prosthetic laryngoplasty in horses: an in vivo and in vitro study. The objective was to evaluate CO2 laser debridement of the cricoarytenoid joint (CAJ) combined with prosthetic laryngoplasty to prevent post-operative loss of arytenoid abduction in seven horses. Horses were assigned to either laser debridement of the left CAJ and laryngoplasty (laser treated, n=5) or control laryngoplasty (sham, n=2), and were evaluated with endoscopic examinations and measurement of right to left angle quotients (RLQ) to assess maintenance of arytenoid abduction. The animals were euthanased at intervals after surgery and larynges were harvested for post-mortem testing, inclu...
A comparison of 3-T magnetic resonance imaging and computed tomography arthrography to identify structural cartilage defects of the fetlock joint in the horse. Articular cartilage defects are prevalent in metacarpo/metatarsophalangeal (MCP/MTP) joints of horses. The aim of this study was to determine and compare the sensitivity and specificity of 3-Tesla magnetic resonance imaging (3-T MRI) and computed tomography arthrography (CTA) to identify structural cartilage defects in the equine MCP/MTP joint. Forty distal cadaver limbs were imaged by CTA (after injection of contrast medium) and by 3-T MRI using specific sequences, namely, dual-echo in the steady-state (DESS), and sampling perfection with application-optimised contrast using different flip-an...
The effect of a gelatin β-tricalcium phosphate sponge loaded with mesenchymal stem cells (MSC), bone morphogenic protein-2, and platelet-rich plasma (PRP) on equine articular cartilage defect. We evaluated the curative efficacy of a gelatin β-tricalcium phosphate (β-TCP) sponge loaded with mesenchymal stem cells (MSC), bone morphogenic protein-2 (BMP-2), and platelet-rich plasma (PRP) by insertion into an experimentally induced osteochondral defect. A hole of 10 mm diameter and depth was drilled in the bilateral medial femoral condyles of 7 thoroughbred horses, and into each either a loaded sponge (treatment) or a saline-infused β-TCP sponge (control) was inserted. After 16 weeks, defects were examined by computed tomography, macroscopic analyses, and histological analyses. The m...
Evaluation of a subject-specific finite-element model of the equine metacarpophalangeal joint under physiological load. The equine metacarpophalangeal (MCP) joint is frequently injured, especially by racehorses in training. Most injuries result from repetitive loading of the subchondral bone and articular cartilage rather than from acute events. The likelihood of injury is multi-factorial but the magnitude of mechanical loading and the number of loading cycles are believed to play an important role. Therefore, an important step in understanding injury is to determine the distribution of load across the articular surface during normal locomotion. A subject-specific finite-element model of the MCP joint was devel...
Compressive fatigue life of subchondral bone of the metacarpal condyle in thoroughbred racehorses. In racehorses, fatigue related subchondral bone injury leads to overt fracture or articular surface collapse and subsequent articular cartilage degeneration. We hypothesised that the fatigue behaviour of equine subchondral bone in compression follows a power law function similar to that observed in cortical and trabecular bone. We determined the fatigue life of equine metacarpal subchondral bone in-vitro and investigated the factors influencing initial bone stiffness. Subchondral bone specimens were loaded cyclically in compression [54MPa (n=6), 66MPa (n=6), 78MPa (n=5), and 90MPa (n=6)] until...
Three dimensional, radiosteriometric analysis (RSA) of equine stifle kinematics and articular surface contact: a cadaveric study. Studies examining the effect of stifle joint angle on tibial rotation, adduction-abduction angle and articular contact area are lacking. Objective: To test the hypothesis that tibial rotation, adduction-abduction angle and articular contact area change with stifle joint angle. Methods: Descriptive study of normal kinematics and articular contact patterns of the equine stifle through the functional range of motion using 3 dimensional (3D) radiosteriometric analysis (RSA) and equine cadaver stifles. Methods: Multiple, radiopaque markers were embedded in the distal femur and proximal tibia and se...
Area of cartilage accessible to curettage for subsequent arthrodesis of the equine proximal interphalangeal joint. Comparison of conventional and collateral ligament sparing approaches. This study compared the areas of cartilage accessible for curettage in arthrodesis of the equine proximal interphalangeal joint using the conventional and collateral ligament sparing approaches. For this purpose, forelimbs and hindlimbs of six equine cadavers without radiographic evidence of proximal interphalangeal joint disease were used. One limb of each pair of limbs was randomly assigned to a dissection using a standard approach to the proximal interphalangeal joint including transection of the collateral ligaments, while each contralateral limb was exposed using the same approach but lea...
Transcriptomic signatures in cartilage ageing. Age is an important factor in the development of osteoarthritis. Microarray studies provide insight into cartilage aging but do not reveal the full transcriptomic phenotype of chondrocytes such as small noncoding RNAs, pseudogenes, and microRNAs. RNA-Seq is a powerful technique for the interrogation of large numbers of transcripts including nonprotein coding RNAs. The aim of the study was to characterise molecular mechanisms associated with age-related changes in gene signatures. Methods: RNA for gene expression analysis using RNA-Seq and real-time PCR analysis was isolated from macroscopicall...
Foetal and postnatal equine articular cartilage development: magnetic resonance imaging and polarised light microscopy. Adult articular cartilage (AC) has a well described multizonal collagen structure. Knowledge of foetal AC organisation and development may provide a prototype for cartilage repair strategies, and improve understanding of structural changes in developmental diseases such as osteochondrosis (OC). The objective of this study was to describe normal development of the spatial architecture of the collagen network of equine AC using 1.5 T magnetic resonance imaging (MRI) and polarised light microscopy (PLM), at sites employed for cartilage repair studies or susceptible to OC. T2-weighted fast-spin e...
Arthroscopic optical coherence tomography provides detailed information on articular cartilage lesions in horses. Arthroscopy enables direct inspection of the articular surface, but provides no information on deeper cartilage layers. Optical coherence tomography (OCT), based on measurement of reflection and backscattering of light, is a diagnostic technique used in cardiovascular surgery and ophthalmology. It provides cross-sectional images at resolutions comparable to that of low-power microscopy. The aim of this study was to determine if OCT is feasible for advanced clinical assessment of lesions in equine articular cartilage during diagnostic arthroscopy. Diagnostic arthroscopy of 36 metacarpophalangea...
Evaluation of osteochondral sample collection guided by computed tomography and magnetic resonance imaging for early detection of osteoarthritis in centrodistal joints of young Icelandic horses. To evaluate the use of CT and MRI for guidance of osteochondral sample collection for histologic detection of early osteoarthritic lesions in centrodistal (distal intertarsal) joints of horses. Methods: Right tarsal joints from the cadavers of 24 Icelandic horses aged 29 to 31 months. Methods: CT and MRI were used to evaluate the extent of suspected osteoarthritic changes in centrodistal joints, which were graded with a semiquantitative system. The anatomic regions with the highest grade of change were identified, and osteochondral samples were obtained from these regions. Samples were also ob...
Shock absorbing ability of articular cartilage and subchondral bone under impact compression. Despite the important role of subchondral bone in maintaining the integrity of the overlying articular cartilage, little research has focused on measuring its mechanical behavior, particularly under injurious load conditions such as impact compression. In this study, the stiffness and the absorbed energy of subchondral bone were compared to that of its overlying cartilage by applying impact compression to equine cartilage-bone specimens. Deformations of the cartilage and subchondral bone were examined independently within the cartilage-bone unit by analyzing real-time images of cartilage-bone ...
Osteochondral repair: evaluation with sweep imaging with fourier transform in an equine model. To evaluate the status of articular cartilage and bone in an equine model of spontaneous repair by using the sweep imaging with Fourier transform (SWIFT) magnetic resonance (MR) imaging technique. Methods: Experiments were approved by the Utrecht University Animal Ethics Committee. Six-millimeter-diameter chondral (n = 5) and osteochondral (n = 5, 3-4 mm deep into subchondral bone) defects were created in the intercarpal joints of seven 2-year-old horses and examined with SWIFT at 9.4 T after spontaneous healing for 12 months. Conventional T2 maps and gradient-echo images were obtained for com...
Effects of serum and autologous conditioned serum on equine articular chondrocytes treated with interleukin-1β. To compare the effects of autologous equine serum (AES) and autologous conditioned serum (ACS) on equine articular chondrocyte metabolism when stimulated with recombinant human (rh) interleukin (IL)-1β. Methods: Articular cartilage and nonconditioned and conditioned serum from 6 young adult horses. Methods: Cartilage samples were digested, and chondrocytes were isolated and formed into pellets. Chondrocyte pellets were treated with each of the following: 10% AES, 10% AES and rhIL-1β, 20% AES and rhIL-1β, 10% ACS and rhIL-1β, and 20% ACS and rhIL-1β, and various effects of these treatments...
Feasibility for mapping cartilage t1 relaxation times in the distal metacarpus3/metatarsus3 of thoroughbred racehorses using delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC): normal cadaver study. Osteoarthritis of the metacarpo/metatarsophalangeal joints is one of the major causes of poor performance in horses. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) may be a useful technique for noninvasively quantifying articular cartilage damage in horses. The purpose of this study was to describe dGEMRIC characteristics of the distal metacarpus3/metatarsus3 (Mc3/Mt3) articular cartilage in 20 cadaver specimens collected from normal Thoroughbred horses. For each specimen, T1 relaxation time was measured from scans acquired precontrast and at 30, 60, 120, and 180...
Histomorphometric evaluation of the effect of early exercise on subchondral vascularity in the third carpal bone of horses. To investigate histomorphometric changes in the cartilage and subchondral bone of the third carpal bone associated with conditioning exercise in young Thoroughbreds. Methods: Nine 18-month-old Thoroughbreds. Procedures-Both third carpal bones of 9 horses (4 exercised spontaneously at pasture only and 5 given additional conditioning exercise beginning at a mean age of 3 weeks) were evaluated. Histomorphometric variables (hyaline and calcified cartilage thickness and collagen orientation; vascular channel area, number, and orientation; and osteochondral junction rugosity) of the third carpal bon...
Non-terminal animal model of post-traumatic osteoarthritis induced by acute joint injury. Develop a non-terminal animal model of acute joint injury that demonstrates clinical and morphological evidence of early post-traumatic osteoarthritis (PTOA). Methods: An osteochondral (OC) fragment was created arthroscopically in one metacarpophalangeal (MCP) joint of 11 horses and the contralateral joint was sham operated. Eleven additional horses served as unoperated controls. Every 2 weeks, force plate analysis, flexion response, joint circumference, and synovial effusion scores were recorded. At weeks 0 and 16, radiographs (all horses) and arthroscopic videos (OC injured and sham joints) ...
Equine articular chondrocytes on MACT scaffolds for cartilage defect treatment. Treatment of cartilage defects poses challenging problems in human and veterinary medicine, especially in horses. This study examines the suitability of applying scaffold materials similar to those used for human cartilage regeneration on equine chondrocytes. Chondrocytes gained from biopsies of the talocrural joint of three horses were propagated in 2D culture and grown on two different scaffold materials, hyaluronan (HYAFF®) and collagen (BioGide®), and evaluated by light and electron microscopy. The equine chondrocytes developed well in both types of materials. They were vital and physiol...
MicroRNA-140 expression during chondrogenic differentiation of equine cord blood-derived mesenchymal stromal cells. MicroRNAs are a class of short noncoding RNAs that are involved in various biological processes, including differentiation. MicroRNA-140 (miR-140) has been identified as a cartilage-specific microRNA with several targets involved in cartilage development and homeostasis. The aim of this study was to investigate the expression of miR-140 during chondrogenic differentiation of equine cord blood-derived mesenchymal stromal cells (eCB-MSCs). We demonstrate both that miR-140 is highly expressed in normal equine articular cartilage and that eCB-MSCs express significantly higher levels of this microR...
Influence of corticosteroids on interleukin-1β-stimulated equine chondrocyte gene expression. To compare the effects of triamcinolone acetonide (TA) and methylprednisolone acetate (MPA) on expression of selected chondrocyte genes in recombinant equine interleukin-1β (reIL-1β) stimulated articular cartilage explants. Methods: In vitro experiment. Methods: Horses (n = 6). Methods: Articular cartilage explants from 2- to 3- year-old horses were exposed to reIL-1β in the presence and absence of TA and MPA at 10(-7) and 10(-6) M. Resting levels of mRNA of anabolic and catabolic genes of chondrocyte origin were quantified using qPCR after 6- and 12-hour incubations. Genes of interest incl...
Equine articular synovial cysts: 16 cases. To report the clinical findings, diagnosis, treatment and outcome of equine patients with articular synovial cysts. Methods: Retrospective case series. Methods: Horses (n = 16) with articular synovial cysts. Methods: Horses diagnosed with articular synovial cysts (1988-2009) at 2 veterinary teaching hospitals were studied. Signalment, history, clinical signs, diagnostic methods and treatment were retrieved and telephone follow-up was obtained. Results: Sixteen horses with articular synovial cysts were identified. Lameness was the reason for referral in most (n = 9) horses. Diagnosis was based ...
Biochemical evaluation of equine articular cartilage through imaging. The use of molecular imaging of cartilage is the next vital step in understanding, treating, and training the equine athlete. Because of the logistics of precontrast and postcontrast medium imaging, the clinical usefulness of the examination has come into question. With the large number of horses undergoing high-field magnetic resonance imaging, the use of contrast medium administration and T1 mapping or T2 imaging precontrast and postcontrast medium administration may add a limited amount of time to the scan and has the potential to provide more detailed information about the chemical composi...
Computed tomographic arthrography of the equine stifle joint. Computed tomographic arthrography is an imaging technique used for the evaluation of the internal structures of a joint, especially the soft tissues and subchondral bone defects that may communicate with the joint space. Clinical indications, technical aspects, principles of image interpretation, and advantages and disadvantages of this imaging technique for the evaluation of the equine stifle joint are discussed in this article.