Topic:Carpal Joint
The carpal joint in horses, also known as the knee, is a complex structure composed of bones, cartilage, ligaments, and synovial fluid that facilitates movement and weight-bearing in the forelimb. It consists of three main articulations: the radiocarpal joint, the midcarpal joint, and the carpometacarpal joint. These articulations are supported by a series of ligaments and tendons that provide stability and flexibility. The carpal joint is susceptible to various conditions such as osteoarthritis, fractures, and synovitis, which can affect the horse's mobility and performance. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, biomechanics, common disorders, diagnostic techniques, and treatment options related to the carpal joint in horses.
Radiographic and pathologic characterization of lateral palmar intercarpal ligament avulsion fractures in the horse. In this study, the radiographic and histologic appearance of lateral palmar intercarpal ligament (LPICL) avulsion in the horse was characterized. Thirty-seven horses with radiographic evidence of avulsion fragments originating from the medial palmar aspect of the ulnar carpal bone were examined. The dorsolateral to palmaromedial projection was useful for evaluating the size and shape of the avulsed bone fragment, and the dorsopalmar projection added information on the relative proximity of the fragment to its fracture bed. Radiographic features that differentiated LPICL avulsion from subchondr...
The effect of speed and gradient on hyperextension of the equine carpus. The equine carpus has a well-defined limit to joint extension at approximately 180 degrees . During locomotion however, the carpus hyperextends during stance phase. Hyperextension is resisted by the carpal bones and ligaments, and it has been proposed that large increased hyperextension might relate to potentially damaging stress levels in the carpus. The aim of this study was to investigate the relationship between peak hyperextension of the carpus (PCE) and speed during locomotion on the level and on an incline. Five Thoroughbred horses were exercised on a treadmill at speeds between 1.8 and...
Pharmacokinetic-pharmacodynamic relationships and dose response to meloxicam in horses with induced arthritis in the right carpal joint. To determine pharmacokinetic-pharmacodynamic (PK-PD) relationships and dose effects for meloxicam in horses and to propose a suitable dosage for use in clinical studies. Methods: 6 adult horses. Methods: The study was conducted by use of a randomized, Latin-square design. Arthritis was induced in the right carpal joint of each horse by administration of Freund's complete adjuvant. Various dosages of meloxicam (0, 0.25, 0.5, 1.0, and 2.0 mg/kg, IV) were then administered. Validated endpoints including stride length and overall clinical lameness score (scale of 0 to 20) were used to assess the e...
Ultrasonography of the medial palmar intercarpal ligament in the Thoroughbred: technique and normal appearance. Tearing of the medial palmar intercarpal ligament (MPICL) has been recognised as a cause of lameness in the Thoroughbred, but diagnosis is difficult due to the nonspecific clinical signs, and can be achieved only by performing arthroscopy on the mid carpal joint (MCJ). It would be beneficial to be able to image the MPICL using ultrasonography to determine whether pathology is present in the ligament in order to aid diagnosis and prognosis. Objective: To determine whether the MPICL could be imaged using ultrasound from the dorsal aspect of the MCJ, and to describe the technique and normal ultra...
Radiographic evaluation of sclerosis of the third carpal bone associated with exercise and the development of lameness in Standardbred racehorses. Sclerosis of the third carpal bone is a common radiographic finding in both lame and sound racehorses, but there are no guidelines correlating degree of sclerosis and incidence of lameness. Objective: To develop a protocol for describing subchondral bone sclerosis in C3 on dorsoproximal-dorsodistal oblique (DPr-DDiO) radiographs of the carpus and to correlate these changes with exercise history and carpal lameness. Methods: One hundred and six Standardbreds entering their first year of training (exercise group) and 7 age-matched Standardbreds at pasture (controls) were examined at approximatel...
Ex vivo magnetic resonance imaging of the distal row of equine carpal bones: assessment of bone sclerosis and cartilage damage. The distal row of carpal bones (C2, C3, and C4) from eight left intercarpal joints--four from Standardbred Trotters and four from Swedish Warmblood horses--were used to assess the potential of magnetic resonance (MR) imaging to detect cartilage and bone lesions. The joints used in the study were classified by macroscopic and radiographic examinations as having normal, mild, moderate, or severe articular cartilage lesions and bone sclerosis. Those classifications correlated well with the appearance of the MR images. Bone sclerosis in the MR images was observed as regions of decreased signal int...
Force- and moment-generating capacities of muscles in the distal forelimb of the horse. A detailed musculoskeletal model of the distal equine forelimb was developed to study the influence of musculoskeletal geometry (i.e. muscle paths) and muscle physiology (i.e. force-length properties) on the force- and moment-generating capacities of muscles crossing the carpal and metacarpophalangeal joints. The distal forelimb skeleton was represented as a five degree-of-freedom kinematic linkage comprised of eight bones (humerus, radius and ulna combined, proximal carpus, distal carpus, metacarpus, proximal phalanx, intermediate phalanx and distal phalanx) and seven joints (elbow, radiocarp...
Tenoscopic release of the equine carpal canal. To develop a tenoscopic method to divide the carpal flexor retinaculum and decompress the carpal canal. Methods: Cadaver specimen study and prospective trial. Methods: Twelve cadaveric limbs, 4 clinically normal horses, and 2 clinically affected horses. Methods-A tenoscopic approach to the proximolateral aspect of the carpal sheath was used to identify and facilitate endoscopic division of the inner and outer layers of the carpal flexor retinaculum in cadaver limbs. The technique was further evaluated in 4 normal and 2 clinically affected horses. Results: Anatomic dissection, intraoperative ob...
Severe carpometacarpal osteoarthritis in older Arabian horses. To report a severe form of carpometacarpal osteoarthritis (CMC-OA) affecting primarily older Arabian horses. Methods: Retrospective study. Methods: Thirty-one horses with CMC-OA. Methods: Carpal radiographs (405 sets) from 3 hospitals were evaluated to identify horses with marked osteoproliferative reaction across the medial aspect of the CMC joint. Owners were contacted to obtain detailed histories and status updates. Necropsy specimens of the CMC joint were evaluated at 2 hospitals to determine the prevalence of 2 variations in the articulation between the proximal second and third metacarpa...
Moment arms about the carpal and metacarpophalangeal joints for flexor and extensor muscles in equine forelimbs. To determine whether muscle moment arms at the carpal and metacarpophalangeal joints can be modeled as fixed-radius pulleys for the range of motion associated with the stance phase of the gait in equine forelimbs. Methods: 4 cadaveric forelimbs from 2 healthy Thoroughbreds. Methods: Thin wire cables were sutured at the musculotendinous junction of 9 forelimb muscles. The cables passed through eyelets at each muscle's origin, wrapped around single-turn potentiometers, and were loaded. Tendon excursions, measured as the changes in lengths of the cables, were recorded during manual rotation of th...
The effect of intra-articular methylprednisolone acetate and exercise on equine carpal subchondral and cancellous bone microhardness. Dorsal carpal osteochondral injury is a major cause of lameness in horses undergoing high intensity training. Intra-articular corticosteroid treatment is used commonly to manage exercise-associated articular pain, but its use remains highly controversial in the equine athlete. This project, therefore, aimed to compare the mechanical properties of intra-articular MPA and diluent-treated middle carpal subchondral and cancellous bone in horses undergoing a short-term treadmill exercise programme. It was hypothesised that subchondral and cancellous bone mechanical properties are influenced by intr...
Synovial regeneration in the equine carpus after arthroscopic mechanical or carbon dioxide laser synovectomy. To compare synovial regeneration in the equine carpus after mechanical or CO(2) laser synovectomy. Methods: Arthroscopic partial synovectomy was performed in the radiocarpal and intercarpal joints. Methods: Twelve horses, 3 to 6 years of age, were randomly divided into 3 groups. Methods: The antebrachiocarpal and intercarpal joints in each horse were randomly assigned a treatment such that each horse had one joint treated as a control (arthroscopic lavage), one in which a mechanical or CO(2) laser partial dorsal carpal synovectomy was performed, and one in which a combination of the mechanical...
Osteoarthrosis of the antebrachiocarpal joint of 7 riding horses. Osteoarthrosis (OA) of the antebrachiocarpal joint from 7 riding horses is described. The horses were old mares and developed severe OA, with ankylosis in some of the joints. The lesions were bilateral, and the owners noticed the lameness in a late event. The cause of severe OA in these mares is not clear. The fact that OA was bilateral indicates that a single traumatic injury is unlikely as an etiologic factor. Considering the severe joint lesions it took long time before the horse-owners noticed the lameness. It is discussed if the threshold of pain is higher in the antebrachiocarpal joint c...
Effects of superior check desmotomy on flexor tendon and suspensory ligament strain in equine cadaver limbs. To measure the effects of transection of the accessory ligament of the superficial digital flexor (SDF) muscle (superior check desmotomy) on flexor tendon and suspensory ligament (SL) strain in vitro. Methods: In vitro experimental biomechanical investigation. ANIMALS USED: Ten equine cadaver forelimbs. Methods: The effects of superior check desmotomy were determined using equine cadaver forelimbs secured in a servocontrolled hydraulic testing machine. Strain sensors were used to measure strain on the superficial and deep digital flexor tendons and SL, and a goniometer was used to measure join...
Biochemical composition of equine carpal articular cartilage is influenced by short-term exercise in a site-specific manner. It was hypothesized that cartilage macro-molecular characteristics are influenced by exercise intensity and by location within a joint. Objective: To determine the macromolecular characteristics of carpal articular cartilage at common and uncommon sites of pathology in horses undergoing high or low intensity exercise, and to compare this composition between exercise groups. Methods: Twelve horses (19.3+/-0.9 years) were assigned to exercise groups. Each group underwent 19 weeks high-intensity treadmill training (N=6) or low-intensity exercise (N=6). Dorsal and palmar test sites were identified...
Fractures of the palmar aspect of the carpal bones in horses: 10 cases (1984-2000). To determine clinical and radiographic findings, treatment, and outcome of horses with fractures of the palmar aspect of the radial carpal bone, with or without concurrent fractures of the palmar surfaces of the other carpal bones. Methods: Retrospective study. Methods: 10 horses. Methods: Medical records were reviewed to obtain information on history, signalment, clinical and radiographic findings, treatment, and outcome. Follow-up information was gathered from owners and referring veterinarians. Results: 7 horses became lame after recovery from general anesthesia for treatment of an unrelate...
Repair of collateral ligament instability in 2 foals by using suture anchors. Instability of the collateral ligaments of the carpal or metacarpophalangeal joint occurred in 2 foals. The instability was repaired using commercial suture anchors. In foals, commercial suture anchors combined with external coaptation can be used successfully to repair collateral ligament instability of the carpus or the metacarpophalangeal joint.
Survey of arthroscopic surgery for carpal chip fractures in thoroughbred racehorses in Japan. Medical and racing records of 155 Thoroughbred racehorses that underwent arthroscopic surgery for carpal chip fractures were investigated. Articular damage for 98.4% of the fractures was classified as G1 or G2 using McIlwraith's criteria. The rate of return to racing after surgery was 82.6%. Evaluation of racing performance after surgery was attempted using a placing index (PI) based on race finish position. There was no significant difference in the PI distribution between horses that underwent surgery and other healthy horses.
Cross-sectional comparison of synovial fluid biochemical markers in equine osteoarthritis and the correlation of these markers with articular cartilage damage. To investigate the relationship between biochemical markers in the synovial fluid of osteoarthritic and contralateral equine joints and gross articular cartilage pathology. Methods: Twenty-two horses underwent bilateral arthroscopy of their carpal or metacarpophalangeal joints following recent onset lameness. The degree of cartilage damage in each joint was scored and synovial fluid, from both the clinically affected and the contralateral joint, was collected. Bone specific alkaline phosphatase (BAP), 5D4 epitope of keratan sulphate (KS), total glycosaminoglycans (GAG) and hyaluronan (HA) were...
Clinical effects of exercise on subchondral bone of carpal and metacarpophalangeal joints in horses. To determine effects of treadmill exercise on subchondral bone of carpal and metacarpophalangeal joints of 2-year-old horses. Methods: 12 healthy 2-year-old horses. Methods: Horses were randomly assigned to the control (n = 6) or exercised (6) groups. Horses in the exercised group ran on a high-speed treadmill 5 d/wk for 6 months. Horses in the control group were hand walked for the same amount of time. Results of clinical, radiographic, nuclear scintigraphic, and computed tomographic examinations, and serum and synovial concentrations of biochemical markers of bone metabolism were compared be...
Evidence supporting an increased presence of reactive oxygen species in the diseased equine joint. Reactive oxygen species (ROS) are capable of degrading many components of the joint in the presence of insufficient antioxidant defences, and as a result have been implicated in the pathogenesis of joint disease in horses. However, to our knowledge, evidence of ROS occurring in diseased joints of horses has not been reported. The objective of this experiment was to compare differences in synovial fluid protein carbonyl content (as a marker of oxidative modification of synovial fluid proteins by ROS) and the antioxidant status of synovial fluid between clinically normal and diseased equine join...
Sclerosis of the third carpal bone. A prospective study of its significance in a group of young standardbred trotters. To assess the significance of radiographic signs of sclerosis of the third carpal bone (C3) in young Standardbred trotters in relation to performance, lameness and bone turnover both carpi in 14 Standardbred trotters were radiographically and scintigraphically examined 6 times, from the beginning of speed training until the beginning of racing, between the mean ages of 20 and 42 months. At the end of the study 8 horses had raced in official qualifying races and 14 limbs in 11 horses had been diagnosed with carpal lameness. All horses but 2 developed sclerosis and all but one had increased bone...
Vacuum phenomenon in equine carpal, metacarpophalangeal and metatarsophalangeal joints. In order to establish the incidence of vacuum phenomenon in horses' carpal, metacarpophalangeal and metatarsophalangeal joints, stress-flexed radiographs were made of normal joints, joints with known pathology and in anaesthetised horses with joints under traction. Focal intra-articular radiolucencies were identified in normal stress-flexed carpal, metacarpophalangeal and metatarsophalangeal joints. These radiolucencies can be confused with those associated with pathological conditions.
Kinematics and ground reaction forces in horses with superficial digital flexor tendinitis. To measure and correlate kinematic and ground reaction force (GRF) data in horses with superficial digital flexor tendinitis. Methods: 6 sound horses. Methods: Horses were evaluated before (sound evaluation) and after (lame evaluation) induction of superficial digital flexor tendinitis in 1 forelimb (randomized) by injection of collagenase. As each horse trotted, kinematic data were collected by use of an optoelectronic system, and GRF data were measured by use of a force plate. Three-dimensional kinematic and GRF data were projected onto a 2-dimensional sagittal plane. Results: Lame limbs had...
Retrospective study of subchondral sclerosis and lucency in the third carpal bone of Standardbred trotters. The aim was to investigate radiographic findings of subchondral sclerosis and subchondral lucency in the dorsoproximal-dorsodistal (DPr-DDi) projection of the third carpal bone (C3) in relation to clinical appearance and to prognosis for racing. In a retrospective study, case records of 89 Standardbred trotters diagnosed with traumatic carpitis confirmed with intra-articular anaesthesia were examined. Records included data on degree of lameness at presentation and after flexion tests and a radiographic examination of the carpus, including a DPr-DDi projection of the C3. Subchondral lucency was...
Impact of injuries and disease on a cohort of two- and three-year-old thoroughbreds in training. A prospective study of injuries and disease in a cohort of Australian thoroughbreds in training was conducted with the participation of 24 trainers. From the horses catalogued at a major yearling sale in 1995, 169 were enrolled in the study and followed through their two- and three-year-old racing seasons. The principal aim was to quantify the time lost in training as a result of the various categories of injuries and disease, recorded as either days of modified training, or weeks rested at pasture. Shin soreness was the most common condition in two-year-olds (affecting 42 per cent of the hors...
The dorsoproximal-dorsodistal projection of the distal carpal bones in horses: an evaluation of different beam-cassette angles. To estimate the extent of the third carpal bone (C3) visible for evaluation in the dorsoproximal-dorsodistal oblique projection of the distal row of carpal bones, 13 forelimbs collected at post mortem from 7 horses were examined radiographically. The limbs were frozen with the carpal joints flexed then radiographed using fixed beam-cassette angles of 15 degrees to 45 degrees, at 5 degree intervals. The influence of beam-cassette angle on; the depth of the proximal articular surface examined, the radiographic appearance of C3 and the assessment of subchondral sclerosis was evaluated. Beam-casse...
Three-dimensional ultrastructure of synoviocytes in the horse joint as revealed by the scanning electron microscope. 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...