Synovial fluid is a viscous, lubricating liquid found within the joint cavities of horses. It serves to reduce friction between the articular cartilage of synovial joints during movement. Composed primarily of hyaluronic acid and lubricin, synovial fluid also contains proteins, electrolytes, and cells. Its composition can change in response to joint disease or injury, making it a subject of interest in veterinary diagnostics. Analyzing synovial fluid can provide insights into joint health, inflammation, and the presence of infections. This page compiles peer-reviewed research studies and scholarly articles that explore the composition, function, and diagnostic applications of synovial fluid in equine medicine.
Frean SP, Lees P.To investigate effects of the anti-arthritic agents hyaluronan and polysulfated glycosaminoglycan (PSGAG) on inflammatory metabolism in cultured equine synoviocytes. Methods: Synoviocytes cultured from samples obtained from the metacarpophalangeal joints of 4 horses. Methods: Equine synoviocytes were grown in monolayer culture. Synoviocytes were stimulated with lipopolysaccharide (LPS) and simultaneously treated with various concentrations of hyaluronan or PSGAG for 48 hours. Three hyaluronan preparations were compared. Prostaglandin E2 (PGE2) concentrations in culture medium were measured, us...
Blaik MA, Hanson RR, Kincaid SA, Hathcock JT, Hudson JA, Baird DK.The objective of this study was to define the normal gross anatomic appearance of the adult equine tarsus on a low-field magnetic resonance (MR) image. Six radiographically normal, adult, equine tarsal cadavers were utilized. Using a scanner with a 0.064 Tesla magnet, images were acquired in the sagittal, transverse and dorsal planes for T1-weighted and the sagittal plane for T2-weighted imaging sequences. Anatomic structures on the MR images were identified and compared with cryosections of the imaged limbs. Optimal image planes were identified for the evaluation of articular cartilage, subch...
Lescun TB, Adams SB, Wu CC, Bill RP.To develop a method for continuous infusion of gentamicin into the tarsocrural joint of horses, to determine pharmacokinetics of gentamicin in synovial fluid of the tarsocrural joint during continuous infusion, and to evaluate effects of continuous infusion of gentamicin on characteristics of the synovial fluid. Methods: 12 healthy adult horses. Methods: An infusion catheter consisting of flow control tubing connected to a balloon infuser was used. Gentamicin solution (100 mg/ml) was infused in the right tarsocrural joint and balanced electrolyte solution was infused in the left tarsocrural jo...
von Rechenberg B, McIlwraith CW, Akens MK, Frisbie DD, Leutenegger C, Auer JA.Nitric oxide (NO), prostaglandin E2 (PGE2), and the activity of neutral metalloproteinases (NMPs) were measured in conditioned media of equine synovial membrane and articular cartilage explant cultures from horses with normal joints (n = 7) and from horses affected with moderate (n = 7) or severe osteoarthritis (n = 14) as judged by macroscopic appearance. Normal articular cartilage appeared glossy and bluish-white, was of normal thickness and showed no evidence of discolouration, fibrillation or other cartilage discontinuity. Slight discolouration and fibrillation or minor clefts of the carti...
Yarbrough TB, Lee MR, Hornof WJ, Koblik PD, Brodack J, Troup C, O'Brien TR, Pool R.To determine the effects of Samarium-153 bound to hydroxyapatite microspheres (153SmM) when injected into the metacarpophalangeal and metatarsophalangeal joints of horses. Methods: - Horses were injected with 153SmM in metacarpophalangeal and metatarsophalangeal joints with the diagonal contralateral joints used as untreated controls. Methods: Twelve adult horses without pre-existing disease involving the metacarpo/metatarsophalangeal joints. Methods: Horses were divided into three groups: high-dose Samarium-153 (12.5 to 17.0 millicurie [mCi]), intermediate dose (6.5 to 12.0 mCi), and low dose...
Brama PA, TeKoppele JM, Beekman B, van El B, Barneveld A, van Weeren PR.To investigate the role of stromelysin (MMP-3) activity in synovial fluid (SF) at different stages of development and in common joint disorders in the horse. Methods: Stromelysin activity was determined with a fluorogenic enzyme activity assay in SF of normal joints of fetal, juvenile and adult horses, and in SF of horses suffering from the developmental orthopaedic disease osteochondrosis (OC) or osteoarthritis (OA). Additionally, MMP-3 activity was expressed as a ratio of previously reported general MMP activity in the same SF samples. Results: The levels of active stromelysin were 30-fold t...
Smith RK, Heinegård D.Cartilage oligomeric matrix protein (COMP) is a noncollagenous extracellular matrix protein found predominantly in cartilage, but also in tendon, ligament and meniscus. Studies in man have demonstrated that it may be used as a prognostic marker in rheumatoid arthritis and osteoarthritis. The present study investigated whether tendon injury contributes to serum and tendon sheath synovial fluid levels of COMP in horses. COMP levels, analysed by competitive ELISA, in the digital sheath synovial fluid were more than 10-fold higher than in the serum. Levels were significantly raised when tendon dam...
Suominen MM, Tulamo RM, Puupponen LM, Sankari SM.To evaluate effects of intra-articular (i.a.) injections of bufexamac on amphotericin B-induced aseptic arthritis in horses. Methods: 24 Standardbred horses. Methods: Aseptic arthritis was induced in the right intercarpal joint by i.a. injection of amphotericin B (20 mg). One week later (day 0), horses were randomly assigned to four 6-horse treatment groups and treated with i.a. injection of 10, 20, or 40 mg of bufexamac suspension (20 mg/ml) or 2.0 ml of sterile saline (0.9% NaCl) solution (control). The treatment was repeated once after 7 days. Clinical lameness examinations and synovial flu...
Fortier LA, Nixon AJ, Ducharme NG, Mohammed HO, Yeager A.To determine the outcome of horses with "complex" digital tenosynovitis treated by tenoscopic proximal annular ligament desmotomy and resection of synovial masses or adhesions, or both, within the digital sheath. Methods: Retrospective evaluation. Methods: Twenty-five horses with a clinical and ultrasonographic diagnosis of palmar or plantar proximal annular ligament constriction and ultrasonographic evidence of synovial masses or adhesions within the digital tendon sheath. Methods: Each horse had tenoscopic surgery for annular ligament desmotomy combined with adhesiolysis and/or synovial mass...
Steel CM, Hunt AR, Adams PL, Robertson ID, Chicken C, Yovich JV, Stick JA.To identify factors affecting the prognosis for survival and athletic use in foals with septic arthritis. Methods: Retrospective study. Methods: 93 foals with septic arthritis. Methods: Medical records were reviewed to obtain clinical findings, laboratory test results, radiographic findings, treatment method, and outcome. Race records for Thoroughbreds and Standardbreds were evaluated to determine whether foals subsequently raced and whether they raced successfully. Results: 43 foals had 1 affected joint, 44 foals had multiple affected joints, and number of affected joints was not recorded for...
Jaraiz MV, Rodriguez C, San Andres MD, Gonzalez F, San Andres MI.Suxibuzone (SBZ), a nonsteroidal anti-inflammatory drug, was administered to 6 horses at a dose rate of 7.5 mg/kg bwt by intravenous (i.v.) route. Plasma and synovial fluid concentrations of suxibuzone and its main active metabolites, phenylbutazone (PBZ) and oxyphenbutazone (OPBZ), were measured simultaneously by a sensitive and specific high-performance liquid chromatographic method. The pharmacokinetic parameters were determined by noncompartmental analysis. Plasma SBZ concentrations rapidly decreased and were not detectable beyond 20 min after treatment. The parent drug was not detected in...
Jaraiz V, Rodriguez C, San Andres MD, Gonzalez F, San Andres MI.A disposition and bioequivalence study with a suxibuzone granulated and a suxibuzone paste oral formulation was performed in horses. Suxibuzone (SBZ) is a nonsteroidal anti-inflammatory drug, which was administered to horses (n = 6) at a dosage of 19 mg/kg bwt by the oral route (p.o.) in a two period cross-over design. Suxibuzone is very rapidly transformed into its main active metabolites, phenylbutazone (PBZ) and oxyphenbutazone (OPBZ). Therefore plasma and synovial fluid concentrations of SBZ, PBZ and OPBZ were simultaneously measured by a sensitive and specific high-performance liquid chro...
Shikichi M, Kitamura HP, Yanase H, Konno A, Takahashi-Iwanaga H, Iwanaga T.The synovial membrane displays a superficial cellular lining composed of two types of synoviocytes: "absorptive" macrophages (type A cells) and "secretory" fibroblast-like cells (type B cells). The types are intermingled and extend a variety of processes, rendering the cellular architecture of the synovial membrane difficult to visualize. Previous electron microscopic and histochemical studies failed to demonstrate the entire shape of synoviocytes, except our immunohistochemical study for protein gene product 9.5 in the horse joint. The present SEM study is the first to demonstrate the three-d...
Armstrong S, Tricklebank P, Lake A, Frean S, Lees P.Carprofen is a Non Steroidal Anti-Inflammatory Drug (NSAID) which is widely used for the treatment of musculoskeletal disorders in horses. The commercial preparation is a racemic mixture of two enantiomers (R and S carprofen). We used HPLC to measure plasma and synovial fluid R and S carprofen concentrations following a single intravenous (i.v.) dose, and computer modelling to determine the pharmacokinetic parameters of the enantiomers in these two body fluids. A comparison was made with results from an identical experiment using ketoprofen. The plasma elimination half lives of R and S carprof...
Simmons EJ, Bertone AL, Hardy J, Weisbrode SE.To quantitate nitric oxide synthase (NOS) activity in healthy and interleukin 1beta (IL-1beta)-exposed equine synovial membrane. Methods: 6 healthy horses, 2 to 8 years old. Methods: Recombinant human IL-1beta (0.35 ng/kg of body weight) was injected intra-articularly into 1 metacarpophalangeal joint of each horse. The contralateral joint served as an unexposed control. All horses were euthanatized 6 hours after injection of IL-1beta, and synovial membrane specimens were assayed for NOS activity by measuring conversion of arginine to citrulline. Severity of inflammation was semiquantitated by ...
Frisbie DD, Ray CS, Ionescu M, Poole AR, Chapman PL, McIlwraith CW.To determine whether serum or synovial fluid concentrations of chondroitin sulfate epitope 846 and carboxy propeptides of type II collagen (CPII) can be used to diagnose osteochondral fragmentation (OC) in horses. Methods: 38 horses with unilateral OC of the radiocarpal (n = 31) or intercarpal (33) joints and 8 clinically and radiographically normal horses. Procedures-For horses with OC, serum and synovial fluid concentrations of epitope 846, CPII, and keratan sulfate (KS) were determined, along with synovial fluid WBC counts and total protein concentrations. Serum epitope 846, CPII, and KS co...
Kitamura HP, Yanase H, Kitamura H, Iwanaga T.Fibroblast-like (Type B) synoviocytes are cells in the synovial membrane that are responsible for production of both synovial fluid and the extracellular matrix in the synovial intima. Immunostaining of the horse synovial membrane for protein gene product (PGP) 9.5, which is a neuron-specific ubiquitin C-terminal hydrolase, demonstrated selective localization of the immunoreactivity in a synoviocyte population different from acid phosphatase-positive Type A synoviocytes. The immunoreactive cells were lined up in the synovial intima and extended dendritic processes towards the joint cavity to f...
Brama PA, TeKoppele JM, Beekman B, van Weeren PR, Barneveld A.To investigate the influence of age, osteoarthritis (OA), and osteochondrosis (OC) on the matrix metalloproteinase (MMP) activity in the synovial fluid (SF) of equine joints. Methods: SF was collected from normal and osteoarthritic metacarpophalangeal joints (normal: 14 adult, 28 juvenile; OA: 22 adult). And from normal and osteochondrotic tarsocrural joints (5 months: 11 normal, 8 OC; 11 months: 7 normal, 6 OC). Subsequently, overall MMP activity was measured. Results: The level of active MMPs was almost twofold higher in SF from juvenile horses (age up to 11 months) than in SF from mature an...
Frisbie DD, Kawcak CE, Baxter GM, Trotter GW, Powers BE, Lassen ED, McIlwraith CW.To determine effects of intra-articularly administered 6alpha-methylprednisolone acetate (MPA) in exercised horses with carpal osteochondral fragmentation. Methods: 18 horses: 3 groups of 6 each. Methods: An osteochondral (chip) fragment was created in 1 randomly chosen middle carpal joint of each horse. Polyionic fluid (PF) was injected into both middle carpal joints of horses in the control group. In horses of the MPA-control group, MPA was injected into the middle carpal joint without an osteochondral fragment; a similar volume of PF was injected into the contralateral middle carpal joint. ...
Okumura M, Tagami M, Fujinaga T.Keratan sulphate (KS) concentration and anticollagen type II antibody levels were measured in the serum and synovial fluid (SF) of clinically normal horses and horses with osteoarthritis (OA). Serum KS in OA was significantly higher than that in normal horses, while no significant difference was found in KS levels of SF between normal and OA. Assays of antibody to collagen type II showed no significant increase in sera and SF of OA. It was suggested that levels of serum KS would be of value in the pathological detection of OA in the joint, although there was no evidence that the measurable aut...
Coté N, Trout DR, Hayes MA.Binding between equine plasma alpha-2-macroglobulin (alpha 2M) and several cytokines known to participate in inflammatory reactions in other species was initially examined. Plasma was obtained from 5 horses with various abnormalities. Samples, both untreated and after reaction with methylamine, were incubated with exogenous, radiolabeled, porcine-derived transforming growth factor-beta-1 (125I-TGF-beta 1), recombinant human interleukin-1-beta (125I-IL-1 beta), and recombinant human tumor necrosis factor-alpha (125I-rhTNF-alpha). They were then subjected to nondenaturing polyacrylamide gel elec...
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...
Okumura M, Fujinaga T.To establish a sensitive and specific monoclonal antibody (MAB) against equine keratan sulfate (KS) and to develop an enzyme immunoassay for measurement of the concentration of KS in serum and synovial fluid from horses. Methods: 18 synovial fluid and 48 serum samples were obtained from clinically normal horses and horses with arthritis. Methods: BALB/c mice were immunized with chondroitinase-ABC-digested proteoglycan monomer from equine joint cartilage, and MAB were raised, using Sp2/O cells as a fusion partner. A competitive ELISA was optimized, using one of the established MAB, and KS conce...
Clegg PD, Coughlan AR, Carter SD.Matrix metalloproteinases (MMPs) are the main enzymes involved in connective tissue turnover. Regulation of MMPs is achieved by controlling production, activation of the pro-enzymes together with the presence of inhibitors, such as, tissue inhibitors of metalloproteinases (TIMPS). The presence of TIMPs in equine synovial fluid was assessed by the ability of the fluid to inhibit equine MMP-9 activity using a gelatin degradation ELISA. The cellular source of the TIMPs was determined using culture supernatants of resident articular cells (chondrocytes and synovial fibroblasts) and invading inflam...
Smith G, Bertone AL, Kaeding C, Simmons EJ, Apostoles S.To evaluate the effect of topically applied dimethylsulfoxide (DMSO) on lipopolysaccharide (LPS)-induced synovitis in the mid-carpal joint. Methods: 6 sound, healthy, adult horses (12 carpi). Methods: In a double-blinded, crossover, paired study with a 1-week washout period, mid-carpal joints were allocated to group 1 (DMSO, n = 6) or group 2 (control, n = 6). Each joint was injected with 1.3 ml (0.0125 ng/dl) of LPS to induce synovitis. For group-1 joints, DMSO gel (15 g; 90%) was applied after injection of LPS and at 12-hour intervals for 60 hours. Joints of group 2 received LPS, but not DMS...
Cornelissen BP, Rijkenhuizen AB, van den Hoogen BM, Rutten VP, Barneveld A.To develop and define a model of acute synovitis/capsulitis in the equine metacarpophalangeal joint (fetlock) to study clinical effects of diagnostic or therapeutic procedures. Methods: 5 adult Standardbreds. Methods: Polyvinyl alcohol foam particles were injected into the left front fetlock of horses; the right front fetlock was used as a control. Horses were examined clinically and for lameness on a regular basis. Blood samples were taken to measure routine variables. Synovial fluid samples were collected from both fetlocks, and macroscopic, microscopic, and biochemical variables were measur...
Todhunter RJ, Fubini SL, Vernier-Singer M, Wootton JA, Lust G, Freeman KP, MacLeod JN.To determine how acute synovitis, with and without intra-articular methylprednisolone acetate (MPA), affect synthesis of proteoglycan, total protein, and collagen in articular cartilage and total protein synthesis in synovial membrane. Methods: Synovitis was induced in 10 ponies by the injection of 0.5 ng lipopolysaccharide (LPS) into the left radiocarpal and midcarpal joints every 2 days for a total of four treatments. Synovitis was documented by clinical examination and synovial fluid analyses. Two days before euthanasia, MPA (0.1 mg/kg) was injected with the last dose of LPS into both the l...
Hills BA, Ethell MT, Hodgson DR.This study was undertaken to determine whether glucocorticosteroids promote the secretion of lubricating surfactant, i.e. surface-active phospholipid (SAPL), into the joint. A standard clinical dose (100 mg) of methylprednisolone acetate (MPA) in 2.5 ml of saline was injected into the load-bearing right radiocarpal joint of five horses and 2.5 ml of saline injected into each of the contralateral joints used as controls. Synovial fluid (SF) was aspirated from all 10 joints before injection and at intervals of 16 and 32 h after injection, and then analysed by standard methods. All test joints sh...
Van den Hoogen BM, van de Lest CH, van Weeren PR, Lafeber FP, Lopes-Cardozo M, van Golde LM, Barneveld A.The purpose of this study was to determine whether changes in the synovial fluid (SF) induced by in vivo loading can induce an alteration in the metabolic activity of chondrocytes in vitro. Therefore, SF was collected from ponies after a period of box rest and after they had exercise for a week. Normal, unloaded articular cartilage explants were cultured in 20% solutions of these SFs for 4 days and chondrocyte activity was determined by glycosaminoglycan (GAG) turnover. In explants cultured in post-exercise SF, GAG synthesis was enhanced and GAG release was diminished when compared to cultures...
Palmer JL, Bertone AL, Malemud CJ, Mansour J.To determine if arthroscopic synovectomy in normal and inflamed joints had temporal or site-related effects on articular cartilage. Methods: Alterations in equine third carpal bone articular cartilage were studied at two time periods: groups 1 and 2 (6 weeks) and groups 3 and 4 (2 weeks) after synovectomy in normal (groups 2 and 4) and inflamed carpi (groups 1 and 3). Methods: 16 carpi from eight horses. Methods: Biochemical and biomechanical properties of dorsal and palmar articular cartilage were determined by radioloabeling, proteoglycan (PG) extraction, chromatography, electrophoresis, and...
Mills JS, Kinsley MA, Peters DF, Weber PSD, Shearer TR, Pease AP.The purpose of this study was to determine whether there was a correlation between circulating and intra-synovial Dkk-1 and radiographic signs of equine osteoarthritis. Methods: Circulating and intra-synovial Dkk-1 levels were measured in clinical cases using a commercially available human Dkk-1 ELISA. Radiographs were performed of the joints from which fluid was collected and these were assessed and scored by a boarded radiologist for joint narrowing, subchondral bone sclerosis, subchondral bone lysis, and periarticular modelling. Comparisons were made between radiographic scores and the conc...
Gustafsson K, Tatz AJ, Dahan R, Britzi M, Soback S, Ahmad WA, Prince H, Kelmer G. The aim of this study was to determine the concentration of metronidazole in the distal interphalangeal joint (DIPJ) of the thoracic limb after administering metronidazole to standing horses by intravenous regional limb perfusion (IVRLP). Methods: Eleven healthy horses had a wide rubber tourniquet applied to the proximal aspect of the antebrachium for 0.5 hours and 500 mg of metronidazole diluted in physiologic saline solution to a total volume of 108 mL was administered by cephalic IVRLP. Synovial fluid samples were collected from the DIPJ before perfusion and at 0.25, 0.5, 2, 12 ...
Soraci AL, Tapia O, Garcia J.Flurbirpofen (FBP), a member of the 2-aryl propionate nonsteroidal anti-inflammatory drug class, has potent anti-inflammatory and analgesic properties. The commercial preparation is a racemic mixture of the R(-) and S(+) enantiomers of FBP. In this study, R(-) and S(+) FBP were used to investigate the metabolic chiral inversion. Each enantiomer was administered separately (0.25 mg/kg) and in a racemic mixture (0.5 mg/kg) intravenously to horses. Plasma and synovial concentration of each enantiomer was determined and the disposition of each was analyzed. After intravenous administration of R(-)...
Cribb NC, Bouré LP, Hanna WJ, Akens MK, Mattson SE, Monteith GJ, Weese JS.To assess the antimicrobial elution characteristics, toxicity, and antimicrobial activity of amikacin-impregnated ferric-hyaluronate implants (AI-FeHAI) for amikacin delivery to the tarsocrural joint of horses. Methods: Experimental study. Methods: AI-FeHAI implants, equine cartilage, and synovium, and horses (n=6). Methods: In vitro study: Five AI-FeHAI were placed in saline solution with daily replacement until implant degradation. Eluent was tested for amikacin concentration and bioactivity. Synovial and cartilage explants were incubated in the presence or absence of AI-FeHAI for 72 hours a...
Wauters J, Pille F, Martens A, Franck T, Serteyn D, Gasthuys F, Meyer E.Equine joint infection is a life-threatening disorder, and confirmation of the diagnosis can be difficult. Synovial fluid biomarkers may assist the discrimination between infectious and noninfectious joint disease. Objective: This study investigates whether the immunological detection of total and enzymatically active myeloperoxidase (MPO) assists the diagnosis of joint infection in horses. Methods: The following 4 sample groups were included: healthy; osteochondritis dissecans (OCD); traumatic synovitis; and culture-confirmed infected joints. Synovial fluid was analysed for total MPO by a hor...
Lloyd KC, Stover SM, Pascoe JR, Pool RR, Kurpershoek C.The effect of gentamicin sulfate, unbuffered and buffered with sodium bicarbonate, on synovial fluid and membrane of clinically normal equine joints was evaluated. Thirty-six adult horses with clinically normal antebrachiocarpal joints were allotted to 6 treatment groups of 6 horses each. One antebrachiocarpal joint in each horse was chosen for treatment. Group-1 horses were given gentamicin (3 ml; 50 mg/ml); group-2 horses were given sodium bicarbonate (3 ml; 1 mEq/ml); group-3 horses were given gentamicin (3 ml; 50 mg/ml) and sodium bicarbonate (3 ml; 1 mEq/ml); group-4 horses were not treat...
Coté N, Trout DR, Hayes MA.Binding between equine plasma alpha-2-macroglobulin (alpha 2M) and several cytokines known to participate in inflammatory reactions in other species was initially examined. Plasma was obtained from 5 horses with various abnormalities. Samples, both untreated and after reaction with methylamine, were incubated with exogenous, radiolabeled, porcine-derived transforming growth factor-beta-1 (125I-TGF-beta 1), recombinant human interleukin-1-beta (125I-IL-1 beta), and recombinant human tumor necrosis factor-alpha (125I-rhTNF-alpha). They were then subjected to nondenaturing polyacrylamide gel elec...
Terschuur JA, Coomer RPC, McKane SA.The objective of this study was to investigate the postoperative use of intrasynovial honey as an antimicrobial after treatment for synovial sepsis in horses. One colt and 2 mares were presented with acute lameness, with or without an associated wound. All 3 cases were initially managed with surgical endoscopic or tenoscopic debridement and lavage for treatment of different synovial structures. Collection of synovial fluid was consistent with synovial sepsis and this was diagnosed in each case. All horses subsequently underwent arthroscopic lavage under general anesthetic and intraarticular or...
Brown MP, Stover SM, Kelly RH, Farver TB.Ten healthy adult mares were given a single intramuscular dose (2.2 mg/kg) of gentamicin sulfate. Over a 48-h period, gentamicin concentrations were measured serially in the serum of all ten mares and in synovial fluid, peritoneal fluid, and urine of six of the mares. The mean peak serum gentamicin concentration was 5.73 micrograms/ml at 1 h. Gentamicin was detected in synovial fluid and peritoneal fluid, with mean peak gentamicin concentrations of 2.41 micrograms/ml and 3.92 micrograms/ml, respectively, observed at 2 h. These concentrations declined in parallel with serum concentrations and w...
Machin J, Duer W, Maylin G, Fenger C, Wilson D, Ivey M, Berthold B, Allison S, Tobin T.Methylprednisolone (MP) acetate is a commonly used corticosteroid for suppression of inflammation in synovial structures in horses. Its use is often regulated in equine sports by plasma MP concentrations. Objective: To describe variability in MP plasma concentrations after MP acetate injection in different synovial structures and with co-administration with hyaluronic acid (HA). Methods: Field study in actively racing horses in three disciplines (Thoroughbred, Standardbred and Quarter Horse). Methods: Seventy-six horses (15 Thoroughbreds, 20 Standardbreds and 41 Quarter Horses) were included i...
Snowden RT, Schumacher J, Blackford JT, Cypher EE, Cox SK, Sun X, Whitlock BK.To determine whether therapeutic concentrations (> 0.5 to 1.0 μg/mL) of polymyxin B (PB) were achieved in the tarsocrural joint of horses when the drug was administered by IV regional limb perfusion (IV-RLP) via a saphenous vein at doses of 25, 50, and 300 mg and to describe any adverse systemic or local effects associated with such administration. Methods: 9 healthy adult horses. Methods: In the first of 2 experiments, 6 horses each received 25 and 50 mg of PB by IV-RLP via a saphenous vein with at least 2 weeks between treatments. For each treatment, a tourniquet was placed at the midmetata...
Ogden NKE, Cullen MD, Stack JD.Accuracy of intrasynovial injections can be challenging to assess in a clinical setting in horses. Contrast-enhanced ultrasonography (CEUS) using injectate agitated with air has been used to determine the success rates of synovial injections in human rheumatology. Objective: To assess the diagnostic sensitivity and specificity of CEUS and to describe its clinical use. Methods: Cadaveric study followed by a prospective descriptive observational study. Methods: Part 1: CEUS was performed following injection of agitated methylene-blue solution targeting 13 different anatomical synovial structures...
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 ...
Skiöldebrand E, Adepu S, Lützelschwab C, Nyström S, Lindahl A, Abrahamsson-Aurell K, Hansson E.This study aimed to test a novel treatment combination (TC) (equivalent to sildenafil, mepivacaine, and glucose) with disease-modifying properties compared to Celestone® bifas® (CB) in a randomized triple-blinded phase III clinical study in horses with mild osteoarthritis (OA). Joint biomarkers (reflecting the articular cartilage and subchondral bone remodelling) and clinical lameness were used as readouts to evaluate the treatment efficacy. Unassigned: Twenty horses with OA-associated lameness in the carpal joint were included in the study and received either TC (n = 10) or CB (n = ...
Osborne AC, Carter SD, May SA, Bennett D.An investigation was made into the possible contribution of autoimmune mechanisms to equine arthropathies. Serum and synovial fluid (SF) immune complexes and anti-collagen Type II antibodies were measured, by ELISA, in groups of horses with naturally occurring osteoarthritis (OA), osteochondritis dissecans (OCD), bone fracture, traumatised joints, synovitis, infected joints and non-diseased (control) joints. Significantly raised anti-collagen Type II antibodies were found in osteoarthritic (P < 0.02) and traumatised joint synovial fluids (P < 0.01) compared with the control, where ten of...
Orsini JA, Moate PJ, Boston RC, Norman T, Engiles J, Benson CE, Poppenga R.In two studies, six healthy adult horses were given imipenem-cilastatin by slow intravenous (i.v.) infusion at an imipenem dosage of 10 mg/kg (study 1) and 20 mg/kg (study 2). The same horses were used in each dosage schedule, with a 2-week washout period between studies. In each dosage group, serial blood and synovial fluid samples were collected for 6 h after completion of the infusion. HPLC was used to determine the imipenem concentration in all samples. Imipenem was well tolerated by all horses at both dosages; no adverse effects were noted during the study period or during the 24-hour pos...
Berg LC, Lenz J, Kjelgaard-Hansen M, Thomsen PD, Jacobsen S.More sensitive and specific diagnostic methods for early detection of changes in the joint cartilage are needed. Cartilage-derived retinoic acid-sensitive protein (CD-RAP) is a potential marker of cartilage synthesis and regeneration. This is the first study on equine CD-RAP. Objective: To evaluate the ability of a commercially available human sandwich ELISA assay to detect equine CD-RAP in synovial fluid from healthy and diseased joints. Methods: Synovial fluid was collected from 28 horses with no signs of joint disease and from 5 with induced inflammatory arthritis. CD-RAP concentrations wer...
Brusie RW, Sullins KE, White NA, Coffin PC, Parker GA, Anver MR, Rosenberger JL.This study was conducted to determine the efficacy of sodium hyaluronate (SH) with antibiotic therapy and joint lavage for reducing acute inflammatory and degenerative changes induced by septic arthritis. Septic arthritis was induced in six adult horses by inoculating the tarsocrural joints with 1 x 10(4) colony-forming units of Staphylococcus aureus. When clinical signs appeared, trimethoprim-sulphamethoxazole (30 mg/kg bodyweight [bwt] daily) and phenylbutazone (4.4 mg/kg bwt sid) were administered and continued until termination of the study (Treatment Day 18). Twenty-four hours post inocul...
Huber MJ, Schmotzer WB, Riebold TW, Watrous BJ, Synder SP, Scott EA, von Matthiessen PC.Four autogenous osteochondral fragments removed from the lateral trochlear ridge of the talus were arthroscopically placed as loose bodies in a randomly selected middle carpal joint in each of 10 horses. The contralateral middle carpal joint, subjected to a sham procedure, served as control. Postoperative treatment was consistent with that for clinical arthroscopic patients. Lameness evaluation, radiographic examination, carpal circumference measurement, and synovial fluid analysis were performed before and at scheduled intervals after surgery. After a 2-month confinement, horses were subjecte...
Duesterdieck-Zellmer KF, Moneta L, Ott JF, Larson MK, Gorman EM, Hunter B, Löhr CV, Payton ME, Morré JT, Maier CS.To determine effects of intraarticularly administered tiludronate on articular cartilage in vivo, eight healthy horses were injected once with tiludronate (low dose tiludronate [LDT] 0.017 mg, n = 4; high dose tiludronate [HDT] 50 mg, n = 4) into one middle carpal joint and with saline into the contralateral joint. Arthrocentesis of both middle carpal joints was performed pre-treatment, and 10 min, 24 h, 48 h, 7 and 14 days after treatment. Synovial nucleated cell counts and total solids, tiludronate, sulfated glycosaminoglycan (sGAG), chondroitin sulfate 846 epitope (CS-846, a measure of aggr...
Svalastoga E, Nielsen K.The histopathological changes in the synovial membrane of bursa podotrochlearis are described in horses with navicular disease. The changes are compared to the histopathological findings in synovial membrane of arthrotic pastern joints in horses and of arthrotic hips in man. A high degree of concordance is demonstrated and this suggests that navicular disease is an arthrotic disease.
Todhunter RJ, Fubini SL, Vernier-Singer M, Wootton JA, Lust G, Freeman KP, MacLeod JN.To determine how acute synovitis, with and without intra-articular methylprednisolone acetate (MPA), affect synthesis of proteoglycan, total protein, and collagen in articular cartilage and total protein synthesis in synovial membrane. Methods: Synovitis was induced in 10 ponies by the injection of 0.5 ng lipopolysaccharide (LPS) into the left radiocarpal and midcarpal joints every 2 days for a total of four treatments. Synovitis was documented by clinical examination and synovial fluid analyses. Two days before euthanasia, MPA (0.1 mg/kg) was injected with the last dose of LPS into both the l...
Little CB, Hilbert BJ, Wickstrom S, Hedlund BE.An alcian blue precipitation method for quantifying the hyaluronic acid (HA) and sulphated glycosaminoglycan concentration (SGAG) in solutions containing both compounds was assessed. The assay was found to be rapid and reliable in solutions containing 0 to 200 mg of HA/dl and 50 to 1,000 micrograms of SGAG/dl, and was not affected by the presence of protein, hemoglobin, or methemoglobin in concentrations normally found in synovial fluid. The HA and SGAG concentrations in intercarpal synovial fluid from 13 clinically normal and 11 arthritic horses were evaluated. A relationship was not found be...
Hunter BG, Duesterdieck-Zellmer KF, Larson MK.Anecdotal accounts of tiludronate administration via intravenous regional limb perfusion (IVRLP) exist despite a lack of information regarding safety for synovial structures in the perfused area. The objective of this study was to determine whether tiludronate concentrations in synovial structures after IVRLP with low dose (0.5 mg, LDT) or high dose (50 mg, HDT) tiludronate remain below a value demonstrated in vitro to be safe for articular cartilage (<19,000 ng/ml), and to determine effects of tiludronate on synovial fluid cytology variables compared to saline perfused control limbs. Using...
Frost AB, Larsen F, Larsen SW, Østergaard J, Thomsen MH, Stürup S, Andersen PH, Larsen C.To establish a pharmacokinetic model for the model drug, sodium diatrizoate (DTZ), allowing joint disappearance kinetics to be estimated from serum appearance kinetics following intra-articular administration, and to calculate the relative joint exposure after intravenous and intra-articular DTZ administration (F(iv/IA)). Methods: Each of five horses received an aqueous solution of 3.9 mg/kg sodium diatrizoate both intravenously and intra-articularly separated by a one-week wash out period. Serum and synovial samples were collected over 7 h and analyzed for content of model compound using indu...
Dumoulin M, Martens A, Van den Abeele AM, Boyen F, Oosterlinck M, Wilderjans H, Gasthuys F, Haesebrouck F, Pille F.This study evaluated the Etest for direct antimicrobial susceptibility testing (AST) of bacteria from equine synovial specimens, incubated in BACTEC enrichment bottles. Ninety-four culture-positive broths were inoculated onto agar to directly determine the minimum inhibitory concentrations (MICs) of 13 antimicrobials, using the Etest (direct Etest). Results were compared with those obtained with the agar dilution reference method, the standard Etest, and the disc diffusion method, after subculture and standardisation of the inoculum. For categorical comparison of AST results, MICs were transla...
Gustafsson K, Tatz AJ, Dahan R, Britzi M, Soback S, Sutton GA, Kelmer G. The aim of this study was to determine the time (T) to the maximum concentration (C) of amikacin sulphate in synovial fluid of the radiocarpal joint (RCJ) following cephalic intravenous regional limb perfusion (IVRLP) using 2 g of amikacin sulphate. Methods: Cephalic IVRLP was performed with 2 g of amikacin sulphate diluted in 0.9% NaCl to a total volume of 100 mL in six healthy adult mixed breed mares. An Esmarch's rubber tourniquet was applied for 30 minutes and the antibiotic solution was infused through a 23-gauge butterfly catheter. Synovial fluid was collected from the RCJ ...
Brown MP, Trumble TN, Merritt KA.To investigate effects of osteochondral injury on high-mobility group box chromosomal protein 1 (HMGB-1) concentrations in synovial fluid (SF) from Thoroughbreds and to compare these results with radiographic and arthroscopic scores of severity of joint injury. Methods: 40 clinically normal rested Thoroughbreds (group 1) and 45 Thoroughbreds with osteochondral injury as a result of racing. Methods: SF was obtained from the metacarpophalangeal (MCP) joints, metatarsophalangeal (MTP) joints, middle carpal joints, and radiocarpal joints. For group 2, radiographic and arthroscopic scores were dete...
Montgomery JB, Klein M, Boire JR, Beck C, Häusermann D, Maksimenko A, Hall CJ.Laminitis is an extremely painful and debilitating condition of horses that can affect their athletic ability and even quality of life. The current gold standard for assessment of laminar tissue is histology, which is the only modality that enables detailed visualization of the lamina. Histology requires dissection of the hoof and therefore can only represent one specific time point. The superior spatial and contrast resolution of synchrotron computed tomography (sCT), when compared with readily available imaging modalities, such as radiographs and conventional CT, provides an opportunity for ...
Jaraiz V, Rodriguez C, San Andres MD, Gonzalez F, San Andres MI.A disposition and bioequivalence study with a suxibuzone granulated and a suxibuzone paste oral formulation was performed in horses. Suxibuzone (SBZ) is a nonsteroidal anti-inflammatory drug, which was administered to horses (n = 6) at a dosage of 19 mg/kg bwt by the oral route (p.o.) in a two period cross-over design. Suxibuzone is very rapidly transformed into its main active metabolites, phenylbutazone (PBZ) and oxyphenbutazone (OPBZ). Therefore plasma and synovial fluid concentrations of SBZ, PBZ and OPBZ were simultaneously measured by a sensitive and specific high-performance liquid chro...