The metacarpophalangeal joint, commonly referred to as the fetlock joint, is a critical anatomical structure in horses, located between the metacarpal bone and the proximal phalanx. It plays a significant role in the locomotion and weight-bearing functions of the forelimbs. This synovial joint is composed of several components, including articular cartilage, joint capsule, ligaments, and synovial fluid, all contributing to its function and stability. The joint undergoes substantial stress during movement, making it susceptible to various disorders, such as osteoarthritis, synovitis, and ligament injuries. This page aggregates peer-reviewed research studies and scholarly articles that explore the anatomy, biomechanics, pathology, and treatment options related to the metacarpophalangeal joint in horses.
Byron CR, Benson BM, Stewart AA, Pondenis HC.To evaluate the effects of methylprednisolone acetate (MPA) on proteoglycan production by equine chondrocytes and to investigate whether glucosamine hydrochloride modulates these effects at clinically relevant concentrations. Methods: Articular cartilage with normal gross appearance from metacarpophalangeal and metatarsophalangeal joints of 8 horses (1 to 10 years of age). Methods: In vitro chondrocyte pellets were pretreated with glucosamine (0, 1, 10, and 100 microg/mL) for 48 hours and exposed to MPA (0, 0.05, and 0.5 mg/mL) for 24 hours. Pellets and media were assayed for proteoglycan prod...
Byron CR, Stewart MC, Stewart AA, Pondenis HC.To evaluate the effects of glucosamine on equine articular chondrocytes and synoviocytes at concentrations clinically relevant to serum and synovial fluid concentrations. Methods: Articular cartilage and synovium with normal gross appearance from metacarpophalangeal and metatarsophalangeal joints of 8 horses (1 to 10 years of age). Methods: In vitro chondrocyte and synoviocyte cell cultures from 8 horses were treated with glucosamine (0.1 to 20 microg/mL) with or without interleukin-1 (IL-1; 10 ng/mL) for 48 hours. Negative control cultures received no glucosamine or IL-1, and positive control...
Holopainen JT, Brama PA, Halmesmäki E, Harjula T, Tuukkanen J, van Weeren PR, Helminen HJ, Hyttinen MM.The effects of growth and maturation on the mineral deposition and the collagen framework of equine subchondral bone (SCB) were studied. Methods: Osteochondral specimens (diameter 6 mm) from the left metacarpophalangeal joint of 5-(n=8), 11-(n=8) and 18-month-old (n=6) horses were investigated at two differently loaded sites (Site 1 (S1): intermittent peak loading; Site 2 (S2): habitual loading). The SCB mineral density (BMD) was measured with peripheral quantitative computer tomography (pQCT), and the data were adjusted against the volume fraction (Vv) of the bone extracellular matrix (ECM). ...
Tenney WA, Whitcomb MB.To characterize ruptures of collateral ligaments (CLs) in metacarpophalangeal and metatarsophalangeal joints in horses. Methods: Retrospective case series. Methods: 17 horses with ruptured CLs. Methods: Data were obtained from medical records, including signalment, history, clinical signs, ultrasonographic and radiographic findings, treatment, and outcome. Additional follow-up information was obtained from owners or referring veterinarians. Results: The lateral CL was ruptured in 11 horses; the medial CL was ruptured in 6 horses. Ultrasonography revealed ipsilateral rupture of the short and lo...
Ugryumova N, Jacobs J, Bonesi M, Matcher SJ.To investigate a novel optical method to determine the three dimensional (3-D) structure of articular cartilage collagen non-destructively. Methods: Polarization-sensitive optical coherence tomography was used to determine the apparent optical birefringence of articular cartilage for a number of different illumination directions. A quantitative method based on the theory of light propagation in uniaxial crystalline materials was validated on equine flexor tendon. Qualitative maps of fiber polar and azimuthal orientation at sites on the posterior and anterior segments of the equine third metaca...
Drum MG, Les CM, Park RD, McIlwraith CW, Kawcak CE.To evaluate whether cutting equine subchondral bone to demarcate specific regions of interest (ROIs) influences the mean density for that bone as measured via quantitative computed tomography (QCT). Sample population-2 metacarpophalangeal joints from equine cadavers. Methods: The distal portion of the third metacarpal bone of each intact metacarpophalangeal joint was scanned via CT to simulate in vivo conditions. Each joint was subsequently disarticulated and dissected, and the distal portion of the dissected third metacarpal bone in air was scanned. Then, six 1-cm(2) areas representing ROIs w...
Lecocq M, Girard CA, Fogarty U, Beauchamp G, Richard H, Laverty S.The earliest osteochondrosis (OC) microscopic lesion reported in the literature was present in the femorotibial joint of a 2-day-old foal suggesting that OC lesions and factors initiating them may arise prior to birth. Objective: To examine the developing equine epiphysis to detect histological changes that could be precursors to OC lesions. Methods: Osteochondral samples from 21 equine fetuses and 13 foals were harvested from selected sites in the scapulohumeral, humeroradial, metacarpophalangeal, femoropatellar, femorotibial, tarsocrural and metatarsophalangeal joints. Sections were stained ...
Vanderperren K, Saunders JH.The metacarpophangeal/metatarsophalangeal (fetlock) joint in the horse is commonly associated with equine lameness and diagnostic imaging is routinely used to investigate disorders of the joint and its surrounding tissues. This review describes the osseous disorders of the fetlock as well as the technical aspects of taking radiographic and ultrasonographic images of the different lesions. In current clinical practice, a combination of radiography and ultrasonography is still the most frequently used approach to arrive at a diagnosis.
Vanderperren K, Ghaye B, Snaps FR, Saunders JH.To determine the detailed computed tomography (CT) anatomy of the metacarpophalangeal (MCP) joint in healthy horses. Methods: 10 cadaveric forelimbs from 10 adult horses without orthopedic disease. Methods: CT of the MCP joint was performed on 4 forelimbs. In 1 of the limbs, CT was also performed after intra-articular injection of 30 mL of contrast medium (40 mg of iodine/mL). Transverse slices 1-mm thick were obtained, and sagittal and dorsal planes were reformatted with a slice thickness of 2 mm. The CT images were matched with corresponding anatomic slices from 6 additional forelimbs. Resul...
Rogers CW, Firth EC, McIlwraith CW, Barneveld A, Goodship AE, Kawcak CE, Smith RK, van Weeren PR.No data exist on the effects of conditioning exercise at foal age on workload and subsequent clinical injury rate during their 2- and 3-year-old racing careers. Objective: To investigate the effects of subjecting TB foals to conditioning exercise prior to the start of race training on: the workload required to reach a level of fitness sufficient to compete; and the prevalence of orthopaedic injury during the first 2 seasons of their racing careers. Methods: Twenty 18-month-old TBs, 12 subjected to conditioning exercise at foal age (CONDEX) and 8 exercised spontaneously at pasture only (PASTEX)...
Sod GA, Mitchell CF, Hubert JD, Martin GS, Gill MS.To compare in vitro monotonic biomechanical properties of an equine spoon plate (ESP) with an axial 3-hole, 4.5 mm narrow dynamic compression plate (DCP) using 5.5 mm cortical screws in conjunction with 2 abaxial transarticular 5.5 mm cortical screws (DCP-TLS) inserted in lag fashion for equine proximal interphalangeal (PIP) joint arthrodesis. Methods: Paired in vitro biomechanical testing of 2 methods of stabilizing cadaveric adult equine forelimb PIP joints. Methods: Cadaveric adult equine forelimbs (n=18 pairs). Methods: For each forelimb pair, 1 PIP joint was stabilized with an ESP (8 hole...
Drum MG, Kawcak CE, Norrdin RW, Park RD, McIlwraith CW, Les CM.Comparison of subchondral bone density determined by quantitative computed tomography (CT) with gross and histopathologic changes have not been made in horses. The goal of this study was to determine if mean quantitative CT density and mean voxel standard deviation are associated with the presence and severity of osteochondral lesions in the palmar aspect of the distal third metacarpal bone in racing horses. Metacarpophalangeal joints from nine racehorses were imaged using CT and scored for gross damage. Four-millimeter-thick sagittal and 30 degrees palmar dorsal plane sections were cut, decal...
Arkill KP, Winlove CP.(1) To establish whether the tidemark and calcified cartilage are permeable to low molecular weight solutes, thereby providing a potential pathway for nutrition of cells in the deep cartilage. (2) To investigate transport from the subchondral microcirculation into calcified cartilage in an intact perfused joint and the effects on transport of static loading. Methods: The permeability of the tidemark and calcified cartilage was investigated in plugs of cartilage and subchondral bone which formed the membrane of a diffusion cell. Transport from the subchondral microcirculation and the effects of...
Sampson SN, Schneider RK, Tucker RL, Gavin PR, Zubrod CJ, Ho CP.Injury to the oblique and straight distal sesamoidean ligaments is becoming recognized as a more common cause of lameness in horses than was previously thought. The purpose of this study was to review the magnetic resonance (MR) imaging findings of 27 horses affected with desmitis of the oblique and/or straight distal sesamoidean ligament and determine long-term prognosis for horses with this diagnosis. Imaging was performed with horses in right lateral recumbency in a high-field 1 T magnet. All horses had lameness localized to the digit or metacarpophalangeal/metatarsophalangeal joint region ...
Easton KL, Kawcak CE.To quantitatively evaluate contact area under 2 loads and subjectively compare contact areas with subchondral bone (SCB) density patterns in intact metacarpophalangeal joints of horses. Methods: 6 forelimbs from horses without musculoskeletal disease. Methods: Computed tomographic scans of intact metacarpophalangeal joints were analyzed to obtain SCB density measurements. Each limb was loaded on a materials testing system to 150 degrees and 120 degrees extension in the metacarpophalangeal joint, and the joint was stained via intra-articular injection with safranin-O or toluidine blue, respecti...
Young BD, Samii VF, Mattoon JS, Weisbrode SE, Bertone AL.To evaluate and correlate patterns of subchondral bone density and articular cartilage degeneration (derived by use of gross, histologic, and computed tomographic [CT] examinations) in equine third metacarpal condyles with and without osteoarthritis. Methods: 8 metacarpophalangeal (MCP) joints (n = 4 horses) without osteoarthritis and 6 osteoarthritis-affected MCP joints (4). Methods: Horses were euthanized. The third metacarpal condyles of the joints were examined grossly and via CT (3 slice images/condyle). For 6 condylar zones, mean bone density and pattern of density distribution were dete...
Bertone AL, Goin S, Kamei SJ, Mattoon JS, Litsky AS, Weisbrode SE, Clarke RB, Plouhar PL, Kaeding CC.Xenogeneic porcine small intestinal submucosa (SIS) is a natural, biodegradable matrix that has been successfully used as a scaffold for repair of tissue defects. The goal of this study was to compare a collateral ligament transection surgically reconstructed with an anchored SIS ligament to a sham-operated control procedure for the correction of joint laxity using an equine model. Ten metacarpophalangeal joints from 10 horses had complete transection of the lateral collateral ligament. In 6 horses, the collateral ligament was reconstructed with a multilaminate strip of SIS anchored with screw...
Clayton HM, Sha D, Stick J, Elvin N.The metacarpophalangeal (MCP) joint and its supporting soft tissues are common sites of injury in athletic horses. Equine gait analysis has focused on 2D analysis in the sagittal plane and little information is available which describes 3D motions of the MCP joint and their possible role in the development of injuries. The aim was to characterize the 3D rotations of the equine MCP joint during walking and trotting. Three-dimensional trajectories of marker triads fixed rigidly to the third metacarpus and proximal phalanx of the right forelimb of healthy horses were recorded at walk (n = 4) and ...
David F, Farley J, Huang H, Lavoie JP, Laverty S.To evaluate mRNA expression of several proinflammatory and anti-inflammatory cytokines and chemokines in equine unstimulated and interleukin-1beta (IL-1beta)-stimulated chondrocytes. Methods: In vitro experiment using equine chondrocyte cultures. Methods: Whole articular cartilage from metacarpophalangeal joints (n=5 horses; 10 fetlocks). Methods: Chondrocyte monolayer cultures were established from digested adult equine articular cartilage and stimulated with 5 ng/mL of recombinant human IL-1beta. RNA was extracted from the cells 24 hours after stimulation. IL-1beta, IL-4, IL-6, IL-8, tumor n...
Benson BM, Byron CR, Pondenis H, Stewart AA.To investigate, in vitro, the effects of radial shock waves on the release of nitric oxide (NO) and synthesis of prostaglandin E2 (PGE2) and glycosaminoglycan (GAG), and liberation of GAG, from equine articular cartilage explants. Methods: Equine cartilage from normal metacarpophalangeal and metatarsophalangeal joints was exposed to radial shock waves at various impulse doses and then maintained as explants in culture for 48 h. Shock waves were delivered at 1,876 Torr pressure and a frequency of 10 Hz. Treatment groups consisted of a negative control group, or application of 500, 2,000, or 4,0...
Lawson SE, Chateau H, Pourcelot P, Denoix JM, Crevier-Denoix N.As equine musculoskeletal models become common, it is important to determine their sensitivity to the simplifications used. A subject-specific distal forelimb model was created using bones extracted from CT scans to examine movement from in-vivo invasive-marker motion capture. The movements of the sesamoid bones were simulated using the constraints of maintaining an isometric virtual ligament and maintaining contact between the appropriate articular surfaces, creating a variable moment arm for the tendons. The simulation of the proximal sesamoid bones was compared to movement recorded in-vitro...
Kuemmerle JM, Uhlig H, Kofler J.Hyaluronate (HA) was administered by intra-articular injection to a 13-year-old Haflinger mare for treatment of metacarpophalangeal osteoarthritis. Ten hours after the injection, a severe inflammatory reaction developed in the treated joint. While awaiting results of synovial fluid analysis, treatment for iatrogenic infectious arthritis was initiated, but the analysis did not confirm sepsis. Clinical signs improved significantly following systemic non-steroidal anti-inflammatory medication and the horse was discharged three days later. Following an intravenous hyaluronate injection, four days ...
Morgan JW, Santschi EM, Zekas LJ, Scollay-Ward MC, Markel MD, Radtke CL, Sample SJ, Keuler NS, Muir P.To compare the orthogonal radiographic (OR) and computed tomographic (CT) appearance of paired Thoroughbred racehorse limbs with severe condylar fracture. Methods: In vitro study. Methods: Cadaveric paired limbs with severe condylar fracture (n=11 horses). Methods: Four standard radiographic and multiple transverse CT images were obtained of the fractured and contralateral limbs centering on the metacarpo/metatarsophalangeal (fetlock) joints. Radiographs and CT images were graded by 4 raters, and interobserver agreement was calculated. Imaging evaluations were supplemented by fetlock joint dis...
Rubio-Martínez LM, López-Sanromán J, Cruz AM, Tendillo F, Rioja E, San Román F.To evaluate the clinical effects and pharmacokinetics of vancomycin in plasma and synovial fluid after intraosseous regional limb perfusion (IORLP) in horses and to compare results with those obtained after IV regional limb perfusion (IVRLP). Methods: 6 horses. Methods: 1 forelimb of each horse received vancomycin hydrochloride (300 mg in 60 mL of saline [0.9% NaCl] solution) via IORLP; the contralateral limb received 60 mL of saline solution (control). Solutions were injected into the medullary cavity of the distal portion of the third metacarpal bone. Synovial fluid from the metacarpophalang...
Hobbs SJ, Richards J, Matuszewski B, Brigden C.To develop and evaluate a marker cluster set for measuring sagittal and extrasagittal movement of joints in the distal portion of the forelimb in ponies. Methods: 4 ponies. Methods: 5 infrared cameras were positioned on a concrete walkway in a frontal-sagittal arc and calibrated. Four segments were defined: hoof, middle phalanx, proximal phalanx, and metacarpus. Rigid clusters with 4 retroreflective markers were placed on each segment. A static trial was recorded with additional anatomic markers on the medial and lateral joint lines. Those anatomic markers were removed, and kinematic data were...
Lejeune JP, Schneider N, Caudron I, Duvivier DH, Serteyn D.Ossification of collateral cartilages is a common radiographic finding in draught horses and indication of a high frequency of interphalangeal osteo-arthropathy have been found in Ardenner horses. This study first aimed at following the evolution of the digits of the forelimbs on radiographic images in a group of 32 Ardenner horses from weaning to 852 +/- 19 days and, secondly, at evaluating the clinical significance of the observed radiographic changes. At 250 +/- 21 days, only 23% of the horses presented a small separate ossification centre of collateral cartilages above the level of the dis...
Smith KJ, Bertone AL, Weisbrode SE, Radmacher M.To identify patterns and correlations of gross, histologic, and gene expression characteristics of articular cartilage from horses with osteoarthritis. Methods: 10 clinically normal horses and 11 horses with osteoarthritis of the metacarpal condyles. Methods: Metacarpophalangeal joints were opened and digitally photographed, and gross lesions were scored and quantified. Representative cartilage specimens were stained for histologic scoring. Total RNA from dorsal and palmar articular surfaces was processed on an equine gene expression microarray. Results: Histologic scores were greater in both ...
van der Harst M, Bull S, Brama PA, Barneveld AB, van Weeren PR, van de Lest C.Osteoarthritis (OA) is a chronic debilitating joint disorder in which the importance of inflammation is increasingly recognized. In advanced cases, both the articular cartilage and the underlying bony layers are affected, but the exact sequence of events and their localization in the initial phase of pathogenesis remain uncertain. We measured nitric oxide (NO) end products in tissue layers that constitute the bearing surface of the joint, as possible indicators of physiological and pathological processes. Methods: Nitrite as a measure for NO and nitrotyrosine was measured in articular cartilag...
Butcher MT, Bertram JE, Benzuidenhout AJ.The distal forelimb of the horse has a complex array of ligaments that play a critical role in determining function of the digit and are often associated with the initiation of foot pathologies. The collateral ligaments of the distal sesamoid bone (CLDS) play an important role in digit stabilization near the end of foot contact and there is also limited evidence to suggest that the CLDS stabilize the proximal interphalangeal joint (PIPJ) during weight bearing. By virtue of their anatomical attachments where the ligaments pass dorsal to the axis of rotation of the PIPJ, it is reasonable to assu...
Walter LJ, Davies HM.Accuracy and limitations of a radiographic technique were established for measurement of metacarpal bone shape in horses. A radiographic index (RI) has been used to measure changes in third metacarpal (Mc3) bone shape in response to training in young racehorses. The aim of these experiments was to determine the effects of positioning of the radiographic equipment on RI measurements from lateromedial radiographs of a left ex vivo metacarpus. Repeatability of the RI measurement in left lateromedial and right mediolateral view Mc3s were evaluated. The width of the dorsal cortex (DC), palmar corte...
Kasper CA, Clayton HM, Wright AK, Skuba EV, Petrie L.Thirteen clinically normal Belgian-type foals were used to study the effects of high doses of oxytetracycline on metacarpophalangeal joint kinematics. Seven foals (treatment group) received 2 doses of oxytetracycline (3 g, IV). The first dose was given when foals were 4 days old; the second dose was given 24 hours later. Six foals (control group) received 2 doses of saline (0.9% NaCl) solution (15 ml, IV) at equivalent time periods. All foals were videotaped at a walk twice: immediately prior to the first treatment and 24 hours after the second treatment. The tapes were digitized, and metacarp...
Fuller CJ, Barr AR, Dieppe PA.An explant system was used to investigate the hypothesis that cartilage from different equine joints might respond differently to challenge with interleukin-1alpha (IL-1alpha). Pairs of normal cartilage samples were taken from the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints of six horses. One of each pair was stimulated with 10 ng/ml human recombinant IL-1alpha for three days, and the supernatants and remaining cartilage explants were analysed for their total content of glycosaminoglycans. A significantly higher percentage of glycosaminoglycans was released ...
Unt VE, Evans J, Reed SR, Pfau T, Weller R.Conformation in horses is often considered an indicator of athletic ability, performance and resistance to orthopaedic disease. Evaluation is performed in the standing horse and repeatability influenced by stance. Ground reaction forces increase in the moving horse as speed increases. Objective: To determine the effect of locomotion on equine carpus, tarsus, metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in the frontal plane. Objective: Valgus/varus angulation will change when moving. Methods: Kinematic data were collected standing, walking and trotting for 2 groups of horses. ...
Straticò P, Guerri G, Palozzo A, Di Francesco P, Vignoli M, Varasano V, Petrizzi L.Capsulitis leads to the release of inflammatory mediators in the joint, causing capsular fibrosis and osteoarthritis (OA). Strain elastosonography (SE) measures the elasticity of tissue by evaluating its strain in operator-dependent deformation. The aims of the study were to assess the feasibility, repeatability, and reproducibility of SE for imaging the distal attachment of the joint capsule (DJC) of metacarpophalangeal joints in sound horses (Group S) and in horses with metacarpophalangeal OA (Group P) and to evaluate differences in the elastosonographic patterns of these horses. After a who...
Norrdin RW, Bay BK, Drews MJ, Martin RB, Stover SM.An overload arthrosis occurs consistently in the palmar region of the metacarpal condyle of the equine fetlock (metacarpophalangeal) joint characterized by subchondral bone sclerosis, devitalization and mechanical failure leading to collapse of the overlying articular cartilage. Samples were selected of joints with mild, moderate, and severe subchondral sclerosis, in which cartilage collapse had not yet occurred. An additional group that had severe sclerosis with focal rarefaction suggesting impending collapse was also studied (n=5/group). Parasagittal slices were milled to 2.0 mm thickness an...
Schade J, de Souza AF, Vincensi LC, Fonteque JH.The objective of this study was to assess the influence of the metacarpophalangeal (MCP) joint angle on the transversal area (TA) and mean echogenicity (ME) of the superficial digital flexor tendon (SDFT) and suspensory ligament (SL) in gaited horses. Ultrasound images were obtained from 50 healthy adult horses of the Mangalarga Marchador (MM; n=25) and Campeiro (n=25) breeds. Static and dynamic angles of the MCP joint were measured from photographs and video recordings. Higher ME values were evinced for the SL only in the group with the smaller dynamic angles of the MCP joint in the MM horses...
Aaltonen K, Niemelä T, Sankari S, Tulamo RM.The purpose of this study was to develop and validate an analytical method to determine the presence of hyaluronic acid derived disaccharides in equine synovial fluid. Results: A high-performance liquid chromatography method for the determination of hyaluronic acid derived unsaturated disaccharides in equine synovial fluid was developed and validated. The method is based on the measurement of unsaturated disaccharides released by digestion of linear hyaluronic acid molecules. The method showed linearity (r(2) = 0.996) over the full working concentration range 0.89-30 mg/l. Relative standard ...
Den Hartog SM, Back W, Brommer H, van Weeren PR.Insight into the loading pattern of the articular cartilage surface during the complete stride is important as biomechanical factors play a pivotal role in the pathogenesis of joint trauma and osteoarthritis (OA). Objective: To determine the loading pattern in the equine MCP articulation in vitro during simulated walk. Methods: Eight cadaveric limbs from mature Dutch Warmblood horses were loaded in a pneumatic loading device in 6 different positions (A1-A6). The pressure distribution on the articular surface of the proximal phalanx (P1) was measured at 7 sites (S1-7) using intra-articularly pl...
Singer E, Garcia T, Stover S.The biomechanical circumstances that promote sagittal fracture of the equine proximal phalanx (P1) are poorly understood. In order to improve our understanding of equine metacarpophalangeal joint (MCPJ) biomechanics and potential aetiologies of sagittal P1 fractures, the study objectives were to quantify P1 bone strains, collateromotion and axial rotation during MCPJ extension under controlled loading circumstances. Unilateral limbs from six cadavers were instrumented with bone reference markers for measurement of P1 movement relative to third metacarpal bone positions during axial limb loadin...
Kelmer G, Martin-Jimenez T, Saxton AM, Catasus C, Elliot SB, Lakritz J.There are no reported studies evaluating the use of erythromycin for regional limb perfusion (RLP) in horses. Our hypothesis was that using the cephalic and saphenous veins for RLP will enable delivery of therapeutic concentrations of erythromycin to the distal limb. Nineteen healthy horses participated in the study. The cephalic, saphenous or palmar digital (PD) vein was used to perfuse the limb with erythromycin. Synovial samples were collected from the metacarpo/metatarso-phalangeal (MCP/MTP) joint and blood samples were collected from the jugular vein. Maximum concentration (C(max)) of ery...
Seabaugh KA, Selberg KT, Valdés-Martínez A, Rao S, Baxter GM.To investigate tissue diffusion of anesthetic agent following administration of low palmar nerve blocks (LPBs) in horses. Methods: Randomized clinical trial. Methods: 12 adult horses. Methods: In 9 horses, mepivacaine hydrochloride-iohexol (50:50 dilution) injections were administered bilaterally (2 or 4 mL/site) to affect the medial and lateral palmar and palmar metacarpal nerves (4 sites). Lateral radiographic views of both metacarpal regions were obtained before and at 5, 15, 30, 60, 90, and 120 minutes after block administration; proximal and distal extents of contrast medium (and presumab...
Smith AJ, Felstead CW, Lawson JS, Weller R.Radiography is the most commonly applied imaging modality in equine practice and forms an essential part of the diagnostic work-up of lame horses. Radiographic signs of musculoskeletal pathology are frequently localized at sites of soft tissue attachment, which are often not clearly visible on radiographs. Different lesions carry different prognoses and require a variety of treatments, and a good knowledge of the position of the synovial structures in the distal limb of the horse is essential for practitioners in the interpretation of radiographs. This study describes a new technique for creat...
Swerczek TW, Donahue JM, Hunt RJ.Scedosporium prolificans was associated with arthritis and degenerative osteomyelitis in a 6-year-old Thoroughbred racehorse. The horse was suspected to have an inflammatory lesion of the interosseous tendon, but treatment had resulted in only a minimal response. Shortly after diagnostic arthrocentesis of the left metacarpophalangeal joint was performed, the joint became severely swollen, and radiography of the area revealed lysis of the distal end of the third metacarpal bone, the proximal sesamoid bones, and the proximal end of the proximal phalanx. The horse did not respond to treatment and...
Mieszkowska M, Adamiak Z, Holak P, Głodek J, Jastrzębska E, Wolińska K, Mieszkowski M.The presented manuscript provides reference for practitioners when measuring normal hoof temperature, as well as controlling the temperature after shoeing with particular shoes. The aim of this study was to determine the effect of horse shoeing with egg bar shoes and shoes with wedge pads on hoof temperature measured by thermography. This was a prospective study conducted on 16 horses. The horses were divided into two groups: horses from group 1 were shod with egg bar shoes, while horses from group 2 were shod with shoes with wedge pads. Thermographic examination was performed below the metaca...
Farley J, Sirois J, MacFarlane PH, Kombé A, Laverty S.To characterize expression of cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) and regulation of prostaglandin E2 (PGE2) production by equine articular chondrocytes. Methods: Articular cartilage from the metacarpophalangeal joints of 7 adult horses. Methods: Equine chondrocyte monolayer cultures were stimulated with different concentrations (2.5, 5, 10, and 20 ng/mL) of recombinant human interleukin-1beta (rhIL-1beta) for 24 hours and then with rhIL-1beta (5 ng/mL) for 3, 6, 9, 12, and 24 hours. Concentration of PGE2 in the media was measured via radioimmunoassay. T...
Viitanen M, Bird J, Maisi P, Smith R, Tulamo RM, May S.As a prerequisite for the identification of navicular disease markers, the concentrations of cartilage oligomeric matrix protein (COMP), total glycosaminoglycans (GAG), hyaluronan, metalloproteinases (MMP) 2 and 9 and total protein were measured in synovial fluid samples obtained from the distal interphalangeal joint (DIP), the metacarpophalangeal joint (MCP) and the navicular bursa of 24 horses. Mean GAG, COMP and total protein levels were significantly higher in the DIP joint and in the navicular bursa compared to the MCP joint. Hyaluronan content was lower. MMP -2 activity was present in al...
Brommer H, Brama PA, Barneveld A, van Weeren PR.The equine metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints, although having virtually the same geometrical appearance, differ in the prevalence of joint pathologies, such as osteochondral fragmentation, and in biomechanical behaviour. The recently developed cartilage degeneration index (CDI) technique offers a possibility to assess quantitatively differences in cartilage degeneration between these joints and to compare these with known differences in biomechanics and clinical observations. Objective: To compare the topographical distribution of articular cartilage degeneration a...
Hoey S, O'Sullivan J, Byrne J, Devine S, Toomey W, McAllister H, Skelly C.Osteochondrosis is a common condition of young horses where there is a failure of endochondral ossification, usually at predisposed sites. The estimated prevalence of osteochondrosis is 33-44%, with radiographic screening of yearlings being used to identify lesions. Radiography has two major limitations: poor sensitivity in detecting cartilaginous lesions and secondly, the exposure of the horse and personnel to ionising radiation. Ultrasonography allows imaging of the articular cartilage and subchondral bone margins and has been shown to be more sensitive in identifying osteochondrosis lesions...
Liley H, Davies H, Firth E, Besier T, Fernandez J.Fatigue failure of bones of the metacarpo-phalangeal (fetlock, MCP) joint is common in thoroughbred racehorses. Stresses within the fetlock joint cartilages are affected by the morphology of the third metacarpal bone (MC3) and proximal phalangeal bone, and the steepness of the median sagittal ridge of MC3 is believed to be associated with fracture. This study investigated the influence of the steepness of the sagittal ridge on cartilage stress distribution using a finite element model of the joint. Changes to the steepness of the sagittal ridge were made by applying a parabolic function to the...
Verschooten F, Verbeeck J.This paper describes the application of a measuring device 'Flextest' to control the effect of traction force and traction time during flexion tests of the distal limb joints of the forelimbs. The optimal force for a flexion test is 100 N, over 1 min. A higher force (150 N) was not harmful. A slightly positive flexion response (100 N/1 min) in a horse with no other clinical signs or radiographic abnormalities is not of clinical significance. Individual left and right flexion and extension angles are almost identical and do not depend on age. Stabled horses which have been rested or horses rest...
Weaver RE, Sharif M, Livingston LA, Andrews KL, Fuller CJ.The objective of this study was to assess whether macroscopically normal articular cartilage taken from joints containing focal osteoarthritic lesions is histologically similar to articular cartilage taken from macroscopically normal joints. Metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints were obtained from 10 horses following euthanasia. Gross articular cartilage damage was scored and the cartilage assigned to one of two groups: (1) macroscopically normal cartilage from normal joints (control) and (2) macroscopically normal cartilage from diseased joints in wh...
Hardy J, Bertone AL, Muir WW.To determine oxygen metabolism, permeability, and blood flow in isolated joints in response to interleukin 1beta (IL-1beta) and contribution of innervation. Methods: One metacarpophalangeal (MCP) joint of 24 adult horses. Methods: The MCP joint was isolated for 6 hours in a pump-perfused, auto-oxygenated, innervated or denervated preparation. Isolated joints were assigned to the following 4 groups: control, control-denervated, inflamed, and inflamed-denervated, and inflammation was induced by intra-articular injection of IL-1beta. Circuit arterial and venous pressures, flows, and blood gas ten...
Niemelä TM, Tulamo RM, Aaltonen K, Sankari SM, Hielm-Björkman AK.Inflammatory and degenerative activity inside the joint can be studied in vivo via analysis of synovial fluid (SF) biomarkers, which are molecular markers of inflammatory processes and tissue turnover. The aim of this study was to investigate the response of selected biomarkers in the SF after an intra-articular (IA) high-molecular-weight non-animal stabilized hyaluronic acid (NASHA) treatment. Our hypothesis was that prostaglandin E (PGE), substance P, aggrecan chondroitin sulfate 846 epitope (CS846), and carboxypeptide of type II collagen (CPII) concentrations in SF would decrease more in th...
Pearce SG, Boure LP, Bolger A, Thomason JJ, Dobson H.To determine the conformational changes in the distal forelimb of horses following heel elevation of 15 degrees and greater. An experimental study with repeated, within-horse measurements. Methods: Five clinically normal, mixed-breed horses were used to determine distal forelimb conformation following heel elevation from 0 to 45 degrees in 15 degree increments. Data were also compared to conformation of the limb in a Kimzey splint. Conformation was determined using lateral to medial radiographic projections. Conformation parameters assessed included measurement of apparent lengths of digital f...
Furniss C, Carstens A, van den Berg SS.This study involves the evaluation of pre-purchase radiographic studies of South African Thoroughbred yearlings. Radiographic changes were recorded and compared with similar international studies. The study differs from other studies in that a lower prevalence of pedal osteitis (1.26%), dorsal osteochondral fragmentation of the metatarsophalangeal joint (1.60%), distal metacarpal sagittal ridge changes (15.7%), ulnar carpal bone lucencies (8.33%), carpal osteophytes (1.19%), distal intertarsal and tarsometatarsal joint radiographic changes (9.92%), tarsal osteochondrosis lesions (4.40%) and st...
Miyakoshi D, Senba H, Shikichi M, Maeda M, Shibata R, Misumi K.This study aimed to evaluate whether radiographic abnormalities at yearling sales were associated with the failure to start racing at 2-3 years of age. Radiographic abnormalities in the carpal (n=852), tarsal (n=976), metacarpophalangeal (n=1,055), and metatarsophalangeal joints (n=1,031) from 1,082 horses, recorded at yearling sale, were reviewed. Eighty-two horses (7.6%) failed to start racing. Radiographic abnormalities such as wedged or collapsed tarsal bones, irregular lucency of a sagittal ridge at the distal aspect of the distal third metatarsal bone, and proximal dorsal fragmentation o...
Drum MG, Les CM, Park RD, McIlwraith CW, Kawcak CE.To evaluate whether cutting equine subchondral bone to demarcate specific regions of interest (ROIs) influences the mean density for that bone as measured via quantitative computed tomography (QCT). Sample population-2 metacarpophalangeal joints from equine cadavers. Methods: The distal portion of the third metacarpal bone of each intact metacarpophalangeal joint was scanned via CT to simulate in vivo conditions. Each joint was subsequently disarticulated and dissected, and the distal portion of the dissected third metacarpal bone in air was scanned. Then, six 1-cm(2) areas representing ROIs w...
Crawley GR, Grant BD, White KK, Barbee DD, Gallina AM, Ratzlaff MH.A modified Cloward's technique was performed for arthrodesis of one metacarpophalangeal (MCP) joint in eight horses. Dorsal arthrotomies were performed medial and lateral to the common digital extensor tendon and two 16 mm holes were drilled through the joint. A perforated cylindrical stainless steel basket filled with cancellous bone was impacted into each hole. The limbs were supported in casts for 8 weeks. The joints were examined and radiographed at 4 weeks, 8 weeks, 6 months, and 10 months. One horse was euthanatized at week 14 to assess the progress of the arthrodesis. In the other seven...
Komosa M, Purzyc H, Fraackowiak H.The main aim of the study was to compare the shape of navicular bones classified as normal and pathologically changed. A comparison of metric features of the navicular bone between different types of horses and associating the examined parameters to the size of the middle and distal phalanges was an additional aspect of the study. The material comprised 53 horses of various breeds which were divided into three types. Through anatomical examinations it was concluded that as many as 30 navicular bones were normal, while 23 were found to present pathological changes. The following methods of stat...
