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.
Anatomical features of the carpal flexor retinaculum of the horse. This study aims to elucidate the topographical anatomy of the carpal flexor retinaculum or palmar anular carpal ligament (PACL) in the horse. Ten specimen of the carpus of five healthy horses were studied by dissection in layers. Slices of 5 mm in thickness facilitated observation of the soft tissues. The superficial layer of the PACL subdivides into five compartments: one for the palmar nerve and the arterial and venous branches, one for only the radial artery, one for the radial vein, and one for the tendon of the radial carpal flexor muscle, and finally for the deep layer that supports all ...
Effects of exercise vs experimental osteoarthritis on imaging outcomes. To identify changes in imaging outcomes in a controlled model of osteoarthritis (OA) vs exercise. Methods: Sixteen 2-year-old horses were randomly assigned to an exercise control (n=8) or an exercise OA (n=8) group. All horses had middle carpal joints arthroscopically explored and an osteochondral fragment was induced in one middle carpal joint of the OA group. All horses were treadmill exercised for the duration of the study (91 days). Clinical, radiographic, nuclear scintigraphic, computed tomographic and magnetic resonance imaging (MRI) examinations were performed and outcomes of these were...
Surgical treatment of carpal flexural deformity in 72 horses. Carpal flexural deformities (CFD) are frequently encountered in the horse, with both congenital and acquired forms described. The success of surgical correction of CFD, both in terms of the ability to achieve a straight palmar carpal angle and the impact on future athletic performance, requires further investigation. Objective: To report the surgical management and outcome of treatment of flexural deformity of the carpus in 72 horses up to 12 months of age. Methods: Information was obtained from the medical records of horses surgically treated for CFD and through follow-up contact with owners....
Comparison of magnetic resonance contrast arthrography and arthroscopic anatomy of the equine palmar lateral outpouching of the middle carpal joint. The objective of this report was to provide an anatomic description of the equine palmar lateral outpouching of the middle carpal joint by comparing its arthroscopic and magnetic resonance (MR) contrast arthrography appearance and to define the structures within the palmar lateral outpouching of the middle carpal joint that can be assessed arthroscopically. MR contrast arthrography was performed on seven cadaveric limbs; images were compared with those obtained during arthroscopic exploration of the palmar lateral outpouching of the middle carpal joint. Gross dissection was performed to confir...
Determination and use of mechanical nociceptive thresholds of the thoracic limb to assess pain associated with induced osteoarthritis of the middle carpal joint in horses. To establish reference mechanical nociceptive threshold (MNT) values of the equine thoracic limb and to assess the use of MNT values to detect pain associated with induced osteoarthritis in the middle carpal joint. Methods: 24 adult horses. Methods: MNT values were evoked by a pressure algometer at 17 sites within each thoracic limb during 2 baseline sessions conducted an average of 5 days apart. Effects of age, sex, weight, and wither height on MNT values were assessed separately for each site. Tolerance of horses to the procedure was graded subjectively and correlated with MNT values. Synovi...
Interleukin-6 and tumour necrosis factor in synovial fluid from horses with carpal joint pathology. The carpal joints are common sites of traumatic arthritis and osteoarthritis (OA) in athletic horses. The pro-inflammatory cytokines interleukin (IL)-6 and tumour necrosis factor (TNF) may be of great importance in the development of intra-articular lesions. The aim of the present study was to investigate possible associations between synovial fluid levels of bioactive IL-6 and TNF and different types of joint lesions seen in traumatic arthritis and OA. Synovial fluid was collected from horses with carpal lameness immediately before arthroscopic surgery. Articular cartilage, synovial membranes...
Outcome of lag-screw treatment of incomplete fractures of the frontal plane of the radial facet of the third carpal bone in horses. To describe outcomes for horses diagnosed with incomplete, non-displaced fractures of the frontal plane of the radial facet (INFR) of the third carpal bone (C3) treated by placement of a lag screw across the fracture under arthroscopic guidance. Methods: Horses (n=13) diagnosed with INFR and treated between December 1999 and January 2005 using a lag screw placed over the fracture were studied. For each case, five horses matched for sire, age and sex which were not known to have INFR were sought for comparison. Racing performance data were collected from a commercial online database. The racing...
Clinical evaluation of a titanium, headless variable-pitched tapered cannulated compression screw for repair of frontal plane slab fractures of the third carpal bone in thoroughbred racehorses. To report clinical evaluation of third carpal bone (C3) frontal plane slab fracture repair with the Acutrak screw system. Methods: Prospective case series. Methods: Racing Thoroughbreds (n=17) with frontal C3 slab fractures. Methods: C3 slab fractures in Thoroughbred racehorses (1999-2004) were repaired by use of the Acutrak screw system. Data collected were (1) preoperative variables--gender, age at injury, limb involved, injury occurrence, fracture thickness, complexity, and displacement, race starts and earnings and (2) postoperative variables were: surgical complications, days to first sta...
Carpal and fetlock conformation of the juvenile Thoroughbred from birth to yearling auction age. There is little information available about conformational changes in the forelimbs of growing foals. Objective: To describe the conformation of the carpus and fetlock of Thoroughbred foals from birth to yearling sale age. Methods: Subjective assessments of the fetlock and carpal conformation of 119 Thoroughbred foals were made within the first month of life and then at 30 day intervals until at least age 120 days. At least 70 subjects were examined further at 60 day intervals until September of their second year. Conformation grades are reported for 5 age groups: first 7 days and at a mean of...
Injuries in the event horse: training versus competition. Two related studies on injuries sustained by event horses during competition and during training are reported. During the cross-country phase of competition, the most common injuries were lacerations and abrasions to the carpus and stifle. Superficial digital flexor tendonitis and exertional rhabdomyolysis were significantly more common during Cours Complete Internationale (CCI) competitions compared to one-day event (ODE) competitions. The difference in injury types at ODEs and CCI competitions probably relates to the increased athletic demands of the CCI and the closer veterinary observation...
Computed tomographic documentation of a comminuted fourth carpal bone fracture associated with carpal instability treated by partial carpal arthrodesis in an Arabian filly. To report treatment of a unilateral comminuted fourth carpal bone (C4) fracture associated with carpal instability by partial carpal arthrodesis (PCA) of the middle carpal joint (MCJ) and carpometacarpal joint (CMCJ). Methods: Case Report. Methods: An 8-month-old Arabian filly. Methods: A C4 slab fracture was diagnosed radiographically; however, fracture comminution was conclusively diagnosed after computed tomographic (CT) imaging. PCA of the MCJ and CMCJ was performed with 2 narrow dynamic compression plates. Results: PCA provided appropriate carpal stability and correct limb alignment immed...
Palmar carpal osteochondral fragments in racehorses: 31 cases (1994-2004). To evaluate records of racehorses with palmar carpal osteochondral fragments and determine whether the fragments were indicators of the severity of pathologic joint changes or prognosis. Methods: Retrospective case series. Methods: 31 racehorses. Methods: Medical records, radiographs, and videos of arthroscopic procedures were reviewed. Information gathered included signalment; location, number, and size of the primary lesion; number and size of palmar carpal fragments; and details pertaining to surgical procedures. Outcome variables were obtained from race records. Results: 31 horses met the ...
Arthroscopic approaches to the palmar aspect of the equine carpus. To identify sites for arthroscopic access to the palmar aspects of the antebrachiocarpal (AC) and middle carpal (MC) joints, and describe visible carpal bone surfaces for each approach. Methods: Prospective experimental study. Methods: Equine carpi: 16 cadavers, 8 live horses. Methods: A latex model was used to identify possible sites for arthroscopic access to the palmar aspects of the AC and MC joints. Carpi (n = 24) were examined arthroscopically and arthroscopic access sites and visible carpal bone surfaces were described. Results: Arthroscopic approaches and instrument portals were develo...
Clinical findings, diagnosis, prevalence and predisposing factors for lameness localised to the middle carpal joint in young Standardbred racehorses. Lameness related to the middle carpal joint (MCJ) occurs in up to 30% of young Standardbred horses in race training and the incidence increase with radiographic severity of third carpal bone (C3) sclerosis on DPr-DDIO (skyline) view of the carpus. Factors predisposing horses to carpal injury have not been well investigated. Objective: To determine the importance of MCJ lameness as a cause of wastage in young Standardbred racehorses, stage of training at which it occurs and predisposing factors, and to describe clinical findings and diagnosis. Methods: Standardbred horses (n = 114) entering the...
Treatment of a second carpal bone fracture by removal under ultrasonographic guidance in a horse. To report an unusual 2nd carpal bone (C2) slab fracture and its treatment, using an ultrasonographically assisted, minimally invasive arthrotomy technique, for fragment removal. Methods: Case report. Methods: An 11-year-old crossbred Warmblood gelding. Methods: A bone fragment, spanning the height of C2, identified on the palmaromedial aspect of C2 was demarcated intraoperatively using ultrasonographically guided needles and removed by arthrotomy. Results: Fracture fragment removal was achieved using a small, ultrasonographically guided arthrotomy. The horse has become sound after treatment an...
Carpal collateral ligament desmopathy in three horses. The radiographic and ultrasonographic findings in three horses with severe damage to the collateral ligaments of the carpus, associated with degenerative joint disease, are described. The horses remained lame despite prolonged rest and medical management, primarily because of the progression of the joint disease. Ultrasonography was found to be an accurate method for diagnosing the injury to the ligaments and is recommended as part of a routine examination in suspected carpal injuries.
Surgical and nonsurgical management of sagittal slab fractures of the third carpal bone in racehorses: 32 cases (1991-2001). To compare results (ie, return to racing and earnings per race start) of surgical versus nonsurgical management of sagittal slab fractures of the third carpal bone in racehorses. Methods: Retrospective study. Methods: 32 racehorses (19 Thoroughbreds, 11 Standardbreds, and 2 Arabians). Methods: Medical records and radiographs were reviewed to obtain information regarding signalment and treatment. Follow-up information was obtained from race records. Robust regression analysis was performed to evaluate earnings per start in horses that raced at least once before and after injury. Results: 22 (69...
Effects of racetrack exercise on third metacarpal and carpal bone of New Zealand thoroughbred horses. The response of equine bone to training has not been quantified in racetrack trained horses, only in treadmill exercised horses. Seven two-year-old thoroughbred fillies were trained on sand and grass at a racetrack, in a typical New Zealand flatrace training regime. The horses were exercised 6 days per week for up to 13 weeks. During the day the horses were confined in 4 x 4m sand yards, and were stalled at night. Another 7 fillies of the same age were allowed free exercise in grass yards. The bones of the animals were available after the 13 week experimental period, and were examined using a ...
Three-dimensional carpal kinematics of trotting horses. Descriptions of 3D kinematics assist in understanding joint function and dysfunction, and are an essential step toward 3D inverse dynamic analysis. Objective: To measure 3D carpal joint motion during trotting. Methods: Three-dimensional trajectories of bone-fixed markers on the radius and third metacarpus of the right forelimb of 3 healthy horses were recorded at 120 Hz using a 6-camera analysis system. Joint kinematics were calculated in terms of helical angles between the 2 segments using a spatial attitude method. Results: All horses showed carpal extension and internal rotation of the meta...
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...