Metatarsal bones in horses are a group of long bones located in the hind limbs, extending from the tarsal bones to the phalanges. These bones play a role in supporting weight and facilitating locomotion. The equine metatarsus typically comprises the third metatarsal bone, also known as the cannon bone, and the second and fourth metatarsal bones, referred to as splint bones. The structure and health of these bones are significant for the overall mobility and performance of the horse. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, function, and clinical considerations of metatarsal bones in equine physiology.
Hughes TK, Eliashar E, Smith RK.To examine the anatomic relationship of the deep branch of the lateral plantar nerve (DBLPN) with structures of the proximal metatarsal region, and to define the anatomic location of a solution injected using a single injection technique for diagnostic analgesia of the proximal suspensory ligament (PSL). Methods: Descriptive study. Methods: Cadaveric equine pelvic limbs (n=29). Methods: The proximal metatarsal region of both pelvic limbs (n=5 horses, 10 limbs) was dissected and measurements were made of anatomic structures relative to the head of the 4th metatarsal bone (HMT4). A single inject...
Brokken MT, Schneider RK, Sampson SN, Tucker RL, Gavin PR, Ho CP.Magnetic resonance (MR) imaging abnormalities in horses with lameness localized to the proximal metacarpal or metatarsal region have not been described. To accomplish that, the medical records of 45 horses evaluated with MR imaging that had lameness localized to either the proximal metacarpal or metatarsal region were reviewed. Abnormalities observed in the proximal suspensory ligament or the accessory ligament of the deep digital flexor tendon included abnormal high signal, enlargement, or alteration in shape. Twenty-three horses had proximal suspensory ligament desmitis (13 hindlimb, 10 fore...
Dykgraaf S, Firth EC, Rogers CW, Kawcak CE.The objective was to determine the effects of early exercise on the articular cartilage and subchondral bone at specific sites of the distal third metacarpal and metatarsal bones of 12 young Thoroughbred horses allowed free choice exercise at pasture. Six of the horses had additional controlled exercise 5 days per week from mean age of 21+/-20 days of age (range: 3-83 days) until 17.1 months of age. Confocal laser scanning microscopy was used to quantify viable and non-viable chondrocytes. Proteoglycan scoring and modified Mankin scoring was performed and subchondral bone mineral density measu...
Just EM, Patan B, Licka TF.To develop a dorsolateral approach to the centrodistal (distal intertarsal) joint in horses and compare its success rate with that of the traditional medial approach in that joint. Methods: 25 cadaveric equine hind limbs, ultrasonographic images, and radiographic views of the tarsal region of 5 and 59 healthy horses, respectively, and 22 horses with a clinical indication for centrodistal joint centesis. Methods: The dorsolateral approach was established anatomically (3 cadaveric limbs), ultrasonographically (5 horses), and radiographically (59 horses). Centrodistal joint arthrocentesis was per...
Epp TL.A 4.5-month-old quarter horse colt was presented with severe right hind metatarsophalangeal varus, present since birth. On radiographs, it was determined that there was a 16 degree deviation with the pivot point at the distal physis of the 3rd metatarsal bone. A step ostectomy in the sagittal plane corrected the deformity. Un poulain Quarter horse âgé de 4,5 mois a été présenté pour une difformité congénitale métatarsophalangienne varus du membre postérieur droit. Une déviation de 16° par rapport au point de pivotement au niveau de la plaque de croissance distale du 3 métatarse a...
Lescun TB, McClure SR, Ward MP, Downs C, Wilson DA, Adams SB, Hawkins JF, Reinertson EL.To evaluate clinical findings, complications, and outcome of horses and foals with third metacarpal, third metatarsal, or phalangeal fractures that were treated with transfixation casting. Methods: Retrospective case series. Animals-29 adult horses and 8 foals with fractures of the third metacarpal or metatarsal bone or the proximal or middle phalanx. Methods: Medical records were reviewed, and follow-up information was obtained. Data were analyzed by use of logistic regression models for survival, fracture healing, return to intended use, pin loosening, pin hole lysis, and complications assoc...
Waselau M, Samii VF, Weisbrode SE, Litsky AS, Bertone AL.To compare biodegradable magnesium phosphate cement (Mg-cement), calcium phosphate cement (Ca-cement), and no cement on bone repair, biocompatibility, and bone adhesive characteristics in vivo in horses. Methods: 8 clinically normal adult horses. Methods: Triangular fragments (1-cm-long arms) were created by Y-shaped osteotomy of the second and fourth metatarsal bones (MTII and MTIV, respectively). Fragments were replaced in pairs to compare Mg-cement (MTII, n = 8; MTIV, 8) with Ca-cement (MTIV, 8) or with no cement (MTII, 8). Clinical and radiographic evaluations were performed for 7 weeks, a...
Branch MV, Murray RC, Dyson SJ, Goodship AE.Understanding of the development of pathology and source of pain in distal tarsal osteoarthritis is poorly understood. Magnetic resonance imaging is often used in the analysis of human osteoarthritis (OA) because it is sensitive to early changes. Objective: In association with distal tarsal joint (DTJ) pain, there will be an alteration in the characteristic subchondral bone (SCB) thickness pattern of horses with no history of pain when subjected to low-level exercise. Methods: Sixteen cadaver tarsal joints were collected from 9 mature horses with a history of tarsal pain and radiographic evide...
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...
Dyson SJ, Weekes JS, Murray RC.The aim of the study was to characterize radiopharmaceutical uptake patterns in horses with clinical and ultrasonographic evidence of proximal suspensory desmitis. It was hypothesized that radiopharmaceutical uptake in the proximal palmar (plantar) aspect of the third metacarpal (metatarsal) bone would be greater in lame limbs of horses with proximal suspensory desmitis than in sound limbs and that there would be a positive correlation between the severity of ultrasonographic abnormalities and the degree of radiopharmaceutical uptake. Nuclear scintigraphic evaluation of the proximal metacarpal...
Bischofberger AS, Konar M, Ohlerth S, Geyer H, Lang J, Ueltschi G, Lischer CJ.The diagnosis of lameness caused by proximal metacarpal and metatarsal pain can be challenging. Magnetic resonance imaging (MRI) offers the possibility for further diagnosis but there have been no studies on the normal MRI appearance of the origin of the suspensory ligament (OSL) in conjunction with ultrasonography and histology. Objective: To describe the MRI appearance of the OSL in fore- and hindlimbs of sound horses and compare it to the ultrasonographic and histological appearance. The findings can be used as reference values to recognise pathology in the OSL. Methods: The OSL in the fore...
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...
Russell TM, Maclean AA.Repair of spiral and long diaphyseal metacarpal and metatarsal fractures under anaesthesia can be problematic and associated with a high incidence of complications, including fracture propagation necessitating euthanasia. Objective: To report on a practical repair technique for which general anaesthesia is not required. Methods: Thirteen racehorses with a spiral/propagating condylar fracture had the fracture repaired using local anaesthesia and sedation, without the need for general anaesthetic. Results: Ten of the horses returned to training and 8 raced again. Two horses were retired directly...
Weekes JS, Murray RC, Dyson SJ.In recent years, pain arising from the proximal metacarpal and metatarsal regions has become well recognized as a cause of lameness and various disease entities have been identified. However, our knowledge of normal patterns of radiopharmaceutical uptake is limited, making interpretation of images problematic. It is therefore important to characterize normal patterns of radiopharmaceutical uptake at specific sites to ensure valid interpretation of images in clinical cases with subtle lesions. The purpose of this study was to describe the pattern of radiopharmaceutical uptake in the proximal me...
Galuppo LD, Simpson EL, Greenman SL, Dowd JP, Ferraro GL, Meagher DM.To report clinical evaluation of headless compression screws for repair of metacarpal/metatarsal (MC/MT3) condylar fractures in horses. Methods: Retrospective case study. Methods: Racing Thoroughbreds (n=16) with nondisplaced lateral condylar fractures of MC/MT 3. Methods: Medical records (1999-2004) of horses with nondisplaced longitudinal fractures of the lateral condyle of MC/MT3 were reviewed. Pre-operative variables retrieved were: patient age, gender, limb involvement, injury occurrence, fracture length, and width, evidence of palmar comminution and degenerative joint disease, number of ...
James FM, Richardson DW.Complications of osteosynthesis including superficial and deep infections continue to affect adversely outcome in equine surgery of the lower limb. Objective: To describe a technique for minimally invasive plate fixation in horses and evaluate clinical results of the technique. Objective: Lower complication rates would occur in horses treated with a minimally invasive approach compared with conventional techniques. Methods: Cases of minimally invasive plate fixation from January 1999 to December 2003 were evaluated. Case records, radiographs and race records for horses that sustained distal th...
Shoemaker RW, Allen AL, Richardson CE, Wilson DG.To evaluate the efficacy and safety of intra-articular administration of ethyl alcohol for arthrodesis of tarsometatarsal joints in horses. Methods: 8 healthy female horses without lameness or radiographic evidence of tarsal joint osteoarthritis. Methods: In each horse, 1 tarsometatarsal joint was treated with 4 mL of 70% ethyl alcohol and the opposite joint was treated with 4 mL of 95% ethyl alcohol. Lameness examinations were performed daily for 2 weeks, followed by monthly evaluations for the duration of the 12-month study. Radiographic evaluations of both tarsi were performed 1 month after...
Bischofberger AS, Ringer SK, Geyer H, Imboden I, Ueltschi G, Lischer CJ.To determine via histologic examination and scintigraphy the effect of focused extracorporeal shock wave therapy (ESWT) on normal bone and the bone-ligament interface in horses. Methods: 6 horses without lameness. Methods: Origins of the suspensory ligament at the metacarpus (35-mm probe depth) and fourth metatarsal bone (5-mm probe depth) were treated twice (days 0 and 16) with 2,000 shocks (energy flux density, 0.15 mJ/mm2). One forelimb and 1 hind limb were randomly treated, and the contralateral limbs served as nontreated controls. Bone scans were performed on days -1 (before ESWT), 3, 16,...
Lischer ChJ, Bischofberger AS, Fürst A, Lang J, Ueltschi G.Lameness in horses due to pain originating from the proximal metacarpal/metatarsal region remains a diagnostic challenge. In cases of obvious lameness the pain can be localised to this region by diagnostic anaesthesia. Because a variety of disorders can cause lameness in this region different imaging modalities including radiography, ultrasonography and scintigraphy should be used to arrive at an accurate diagnosis. Even though a precise anatomic-pathologic diagnosis can still be an enigma, because not only bone and joints, but also soft tissue structures including the proximal suspensory liga...
The Journal of physiologyFebruary 9, 2006
Volume 572, Issue Pt 1 155-164 doi: 10.1113/jphysiol.2006.105635
O'Connor SJ, Ousey JC, Gardner DS, Fowden AL, Giussani DA.This study investigated, in vivo, the mechanisms underlying the development of cardiovascular function in the horse fetus, with particular relevance to baroreflex function and hind limb vascular arterial reactivity to constrictor agonists. Under general anaesthesia, vascular catheters were inserted and a Transonic flow probe was implanted around one of the metatarsal arteries of 13 horse fetuses, either at 0.6 of gestation (n= 6) or at 0.9 of gestation (n= 7, term approximately 335 days). At least 5 days after surgery, pressor, vasoconstrictor and cardiac chronotropic responses to exogenous bo...
Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL.The characteristics of, and pre-existing pathology associated with 75 cases of fatal lateral condylar fracture sustained by Thoroughbreds while racing in the UK were described. Cases were identified from 220 cases of fatal distal limb fracture submitted as part of studies designed to identify risk factors for all fatal distal limb fractures. Fractures were most common in hurdle races and affected the right forelimb twice as often as the left forelimb. Fracture dimensions were similar to previous reports, however there was a much greater prevalence of articular and diaphyseal comminution and of...
Jackson M, Geyer H, Fürst A.This study concerns the vestigial metacarpal and metatarsal bones, so called splint bones. The soft tissues, which stabilize the splint bones were carefully examined. The palmar metacarpal/plantar metatarsal fascia, the metacarpal/metatarsal interosseous ligaments and the fibres, which exit distally from the splint bone, were examined in depth. Cadaveric distal limbs were collected from 5 slaughtered or euthanized horses. The legs were examined both, microscopically and macroscopically. The palmar metacarpal/plantar metatarsal fascia is a very stable structure, which connects the splint bone w...
Gee EK, Firth EC, Morel PC, Fennessy PF, Grace ND, Mogg TD.To assess the relationship between the radiographic and microscopic appearance of the physeal regions of the distal third metacarpal (Mc3) and metatarsal (Mt3) bones of Thoroughbred foals at 160 days of age, and to clinically assess changes in contour of the distal Mc3 and Mt3 physeal regions from birth to 160 days of age. To assess relationships between maximum clinical physis scores and age, time of year, foal's sex, condition score, growth rate, copper (Cu) concentration in the liver of the foal, and supplementation of the dam with Cu in late gestation. Methods: Dams were given Cu (n=5 and ...
Verna M, Turner TA, Anderson KL.Nonfocused extracorporeal shock wave therapy (ESWT) treatment protocol is commonly used in veterinary practice. This study investigated the effects of four nonfocused ESWT treatments, given 2 weeks apart, on bone radiopharmaceutical uptake and radiographic and thermographic appearance in the metacarpal and metatarsal regions in six adult untrained horses. There were no measurable treatment effects determined by thermography (daily), scintigraphy (at 2-week intervals), and radiography (before study initiation and at study completion) between treated and control limbs. It was concluded that no g...
Byron CR, Benson BM, Stewart AA, Stewart MC.To investigate in vitro effects of radial shock waves on membrane permeability, viability, and structure of chondrocytes and articular cartilage. Methods: Cartilage explants obtained from the third metacarpal and metatarsal bones of 6 horses. Methods: Equine cartilage was subjected to radial shock waves and then maintained as explants in culture for 48 hours. Treatment groups consisted of a negative control group; application of 500, 2,000, and 4,000 impulses by use of a convex handpiece (group A); and application of 500, 2,000, and 4,000 impulses by use of a concave handpiece (group B). Effec...
Ringer SK, Lischer CJ, Ueltschi G.To monitor the effect of focused extra-corporeal shock wave therapy (ESWT) on bone and bone-tendon junction of horses without lameness by use of nuclear scintigraphy and thermography. Methods: 6 warmblood horses without lameness. Methods: The origin of the suspensory ligament at the metacarpus (OSL-MC) and the fourth metatarsal bone were treated at 2 time points (days 0 and 16) with 2,000 shocks applied by a focused ESWT device at an energy flux density of 0.15 mJ/mm2. One forelimb and 1 hind limb were treated, and the contralateral limbs served as controls. To document the effect of focused E...
Branch MV, Murray RC, Dyson SJ, Goodship AE.Osteoarthritis (OA) is a common cause of distal tarsal pain, but disease development is poorly understood. Awareness of normal tarsal structure and function is important in order to understand the pathogenesis of OA. Thickening of the subchondral bone (SCB) plate has been related to the development of OA, but SCB plate patterns in the equine tarsus have not been documented. Objective: There is a repeatable pattern of SCB thickness across the distal tarsal joints, and specifically that thickness would be greatest dorsally and laterally. Methods: Twenty cadaver tarsi were collected from mature h...
Barr ED, Clegg PD, Mark Senior J, Singer ER.To describe focal destructive lesions of the proximal sesamoid bones (PSBs) as a complication of dorsal metatarsal artery catheterization performed for direct blood pressure monitoring during equine general anesthesia. Methods: Retrospective study. Methods: Three client-owned horses. Methods: A dorsal metatarsal artery was catheterized in each of 3 horses for direct blood pressure monitoring during anesthesia. Radiography, ultrasonography, synoviocentesis, and arthroscopy were used to diagnose postoperative lameness that occurred in the limb used for blood pressure monitoring. Results: Horses ...
Firth EC, Rogers CW, Doube M, Jopson NB.To determine the effect of a known training regimen on the size and mineral content of the third metacarpal (Mc3) and third metatarsal (Mt3) bones of 2-year-old Thoroughbred horses trained on racetracks. Methods: Mc3 and Mt3 of seven horses trained on grass and sand tracks were scanned at several sites using conventional quantitative and peripheral computed tomography (CT). Bone dimensions and density in the diaphysis and epiphysis were compared with those from seven untrained horses. Calcein label was injected in two clusters, during Weeks 9 and 12. The extent and rate of diaphyseal modelling...
McD○ LA, Stover SM, Coleman K.To determine a range of limb loading activity for healthy adult horses confined to box stalls in an equine veterinary teaching hospital and determine the effects of hospital environmental factors on load rates and daily limb loading patterns. Methods: 6 mature healthy horses of various ages, breeds, and sexes, and 1 horse with a repaired metatarsal fracture. Methods: Step monitors were placed on 2 limbs of adult horses confined to box stalls. Relocation steps and weight shifts were recorded, as loading events, for 24 hours. Influence of forelimb versus hind limb and environmental factors on lo...
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...
Milner PI, Dimmock O, Barnes K.Neurovascular variation may be relevant when performing surgical techniques to the proximal plantar metatarsal region. Objective: To document variations in the neurovascular anatomy of the proximal plantar metatarsal region and study the relationship of the neurovascular components to each other and other structures located in this area. Methods: Descriptive anatomical study. Methods: Paired cadaver hind limbs from 15 horses were dissected from the distal tibia to the metatarsophalangeal joint. Deep branch of the lateral plantar nerve (DBLPN) length, location of its origin from the lateral pla...
Hanson PD, Markel MD, Vanderby R.We evaluated the single-cycle structural properties for axial compression, torsion, and 4-point bending with a central load applied to the caudal or lateral surface of a diaphyseal segment from the normal adult equine humerus, radius, third metacarpal bone, femur, tibia, and third metatarsal bone. Stiffness values were determined from load-deformation curves for each bone and test mode. Compressive stiffness ranged from a low of 2,690 N/mm for the humerus to a high of 5,670 N/mm for the femur. Torsional stiffness ranged from 558 N.m/rad for the third metacarpal bone to 2,080 N.m/rad for the fe...
The Journal of physiologyFebruary 9, 2006
Volume 572, Issue Pt 1 155-164 doi: 10.1113/jphysiol.2006.105635
O'Connor SJ, Ousey JC, Gardner DS, Fowden AL, Giussani DA.This study investigated, in vivo, the mechanisms underlying the development of cardiovascular function in the horse fetus, with particular relevance to baroreflex function and hind limb vascular arterial reactivity to constrictor agonists. Under general anaesthesia, vascular catheters were inserted and a Transonic flow probe was implanted around one of the metatarsal arteries of 13 horse fetuses, either at 0.6 of gestation (n= 6) or at 0.9 of gestation (n= 7, term approximately 335 days). At least 5 days after surgery, pressor, vasoconstrictor and cardiac chronotropic responses to exogenous bo...
Jenson PW, Gaughan EM, Lillich JD, Bryant JE.To determine clinical findings in and outcome of horses with fractures of the second or fourth metacarpal or metatarsal bone that underwent segmental ostectomy, leaving the proximal and distal portions of the bone undisturbed. Methods: Retrospective case series. Methods: 17 horses. Methods: Medical records were reviewed, and information on signalment, affected bone, lesion type, surgical procedure, amount of bone removed, and surgical and postsurgical complications was obtained. Follow-up information was obtained through telephone conversations with owners, trainers, and referring veterinarian...
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...
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...
Staller GS, Richardson DW, Nunamaker DM, Provost M.Contact area and pressure between 6-hole broad dynamic compression plates and 20 pairs of equine third metatarsal bones were measured using nonluted and luted plating techniques. Pressure-sensitive film (pressure ranges 10 to 50 MPa and 50 to 130 MPa) was used as the static pressure transducer. Nonluted and one of two luting techniques were tested on each pair of bones; each luting technique was tested on 20 bones. Quantitative determinations of contact area and pressure were made using computerized image processing techniques. Mean (+/- SD) total contact area for nonluted plates was 18.49% +/...
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...
Glade MJ, Luba NK, Schryver HF.The application of transmission ultrasonics to the equine cannon holds promise as a method of monitoring metacarpal and metatarsal development, quality and integrity under a variety of experimental and field conditions. The validity of relating the velocities of sound pulses transmitted through the cannon to the mechanical breaking strengths of these bones was tested in two studies. Breaking strengths calculated from the sound velocities through sections of the metacarpal bones from 14 yearling ponies and 12 yearling horses were highly correlated with the mechanical breaking strengths of those...
Müller EMT, Vanderperren K, Merle R, Rheinfeld S, Leelamankong P, Lischer CJ, Ehrle A.The objective of this retrospective, observational, controlled study was to evaluate bone and soft tissue window CT images of the proximoplantar metatarsus III region in twenty horses with pain localized to the proximal suspensory ligament (PSL) and 20 horses with findings nonrelated to tarsal pain. All horses underwent CT and radiographic examination. Images were reviewed by three independent observers who graded the severity and localization of findings. Bone-related categories as well as soft tissue-related categories were evaluated. For the comparison of imaging findings in horses with and...
Bassage LH, Ross MW.Ten horses admitted for lameness evaluation including bone scintigraphy had enostosis-like lesions, described scintigraphically as focal or multifocal areas of intense increased radioisotope uptake within the medullary cavity of one or more long bones, and radiographically as one or multiple round to irregularly shaped radiopacities within the medullary cavity, often in close proximity to the nutrient foramen. There were 6 Thoroughbreds, one male, one female and 4 geldings, 3 Standardbreds, all geldings and one Appaloosa gelding; age 3-10 years. Enostosis-like lesions were seen in the tibia (5...
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...
Baxter GM, Doran RE, Allen D.Proximal open comminuted fractures of the fourth metatarsal bone (Mt IV) in eight horses were treated by complete removal of the affected bone and antimicrobial therapy. Two horses had concurrent septic arthritis of the tarsocrural or distal tarsal articulations, and five horses had radiographic evidence of osteomyelitis and sequestration of the affected bone. Five horses became athletically sound for their intended use, two horses with septic arthritis had residual lameness but were pasture sound, and one horse was lost to follow-up. Excision of the entire bone appears to be an acceptable tre...
Biggi M, Dyson SJ, Murray RC.Our aims were to evaluate the pattern of radiopharmaceutical uptake in horses with lameness related to the metacarpophalangeal and/or metatarsophalangeal joint and compare the results with similar information from sound horses. It was hypothesized bthat there would be a difference in radiopharmaceutical uptake between the lame and contralateral limb in unilaterally lame horses and that there would be a difference between lame and sound horses. Nuclear scintigraphic images of 43 horses with forelimb lameness and 30 horses with hindlimb lameness were evaluated. In all horses lameness was improve...
Ross MW, Sponseller ML, Gill HE, Moyer W.Articular fracture of the dorsoproximolateral aspect of the third metatarsal bone (MT3) caused an acute onset of lameness in 5 horses; however, 3 of the horses had historical and radiographic or scintigraphic evidence of chronic tarsal and metatarsal disease before fracture. The pathogenesis of dorsoproximolateral fracture of MT3 remains unclear, but the fracture may occur as a result of the formation of abnormal bone in the proximal aspect of MT3. The prognosis for racing in horses with this fracture appears to be guarded.
Roneus B, Arnason T, Collinder E, Rasmussen M.A clinical material of 133 Standardbred horses with palmar/plantar osteochondral fragments (POF) in the metacarpo- and metatarsophalangeal joints were studied. All horses had their fragments removed with arthroscopic surgery. 102 of the horses were 3 years old or younger when surgery was performed. Anatomical localisations of the fragments were in agreement with earlier reports. There was no statistical significant difference in month of birth in the POF--group compared to the total population. Eighty % of the horses that had raced before surgery came back to racing. The racing performance rel...
Weekes JS, Murray RC, Dyson SJ.In recent years, pain arising from the proximal metacarpal and metatarsal regions has become well recognized as a cause of lameness and various disease entities have been identified. However, our knowledge of normal patterns of radiopharmaceutical uptake is limited, making interpretation of images problematic. It is therefore important to characterize normal patterns of radiopharmaceutical uptake at specific sites to ensure valid interpretation of images in clinical cases with subtle lesions. The purpose of this study was to describe the pattern of radiopharmaceutical uptake in the proximal me...
Yovich JV, Turner AS, Stashak TS, McIlwraith CW.Lateral or medial luxation of the metacarpophalangeal or metatarsophalangeal (fetlock) joint in 10 horses is presented. Closed and open fetlock luxation each occurred in five horses. Horses were treated by cast immobilisation after debridement of soft tissue and joint lavage in cases of open luxations. Suture apposition of a ruptured collateral ligament was attempted in three cases. Antibiotic therapy was used in all cases of open fetlock luxation but non-steroidal anti-inflammatory medication was used inconsistently. Whether closed or open, fetlock luxations had a good prognosis for return to...
El-Gendy SAA, Alsafy MAM, Rutland CS, El-Khamary AN, Abu-Ahmed HM, El-Kammar MH.The donkey is of socio-economic value yet imaging techniques in both healthy and abnormal limbs are a limiting factor in research and medicine. The objective was to determine anatomical features of both healthy and clinically abnormal donkey metacarpophalangeal and metatarsophalangeal joints (n = 13) using anatomical dissection, casting, X-ray and computed tomography. The joint capsule contained two palmar/plantar and two dorsal recesses. The proximal-palmar or plantar recess was larger than the distodorsal recess and potential sites of approaches to the recesses were determined. Soft tissue ...
Desjardins MR, Vachon AM.A chronic Rhodococcus equi metaphysitis involving the distal growth plate of the left third metatarsal bone had induced a longstanding lameness in a young foal. Abnormal hematologic values included mild anemia, hyperfibrinogemia, mild leukocytosis, and neutrophilia. Radiography of the distal portion of MT3 revealed a radiolucent zone on the medial aspect of the growth plate, and small pieces of bone suggestive of sequestra. Treatment with erythromycin estolate and rifampin, aggressive surgical debridement, and cancellous bone grafting helped resolve the bone infection.
Russell TM, Maclean AA.Repair of spiral and long diaphyseal metacarpal and metatarsal fractures under anaesthesia can be problematic and associated with a high incidence of complications, including fracture propagation necessitating euthanasia. Objective: To report on a practical repair technique for which general anaesthesia is not required. Methods: Thirteen racehorses with a spiral/propagating condylar fracture had the fracture repaired using local anaesthesia and sedation, without the need for general anaesthetic. Results: Ten of the horses returned to training and 8 raced again. Two horses were retired directly...
Specht TE, Poulos PW, Metcalf MR, Robertson ID.Vacuum phenomenon was induced inadvertently during radiographic examination of a metatarsophalangeal joint of a lame horse. The phenomenon was recreated in a sound horse when a metacarpophalangeal joint was radiographed in a stress-flexed position. Distraction of apposing articular surfaces may induce the vacuum phenomenon, which could result in misdiagnosis of an osteochondral defect or fracture.
Markel MD, Snyder JR, Hornof WJ, Meagher DM.Nuclear scintigraphy was used to evaluate healing of third metacarpal bone (MC III) fractures in 2 horses (horses 1 and 2) and a third metatarsal bone fracture in 1 horse (horse 3) after stabilization of each fracture with 2 broad dynamic compression plates. In horse 1, the fracture had uniform uptake of 99mTc methylene diphosphonate on days 1, 15, and 30 after surgery. The fracture healed, and the horse was discharged from the clinic on day 52. In horse 2, a 6-cm photopenic region (ie, area of low radioactivity) was seen over the diaphysis of MC III on day 3. The region persisted and became m...
Kośla T, Anke M, Grün M.The breed of horses took a significant effect on the Pb content of animals with a normal Pb supply. Warm-blooded horses stored more Pb in skeleton, kidneys, liver and cerebrum than heavy horses. The sex only had the trend of influencing the Pb status. Mares with a normal Pb supply incorporated more Pb than geldings. Age only took a slight effect on the skeleton. Older horses stored more Pb in the metatarsal bone than younger ones. The Pb content of horse meat was not influenced by Pb exposure. Pb was not additionally deposited in the musculature. The Pb offer of the living area took a signific...
Schamhardt HC, Hartman W, Lammertink JL.Strain gauge rosettes were bonded to the dorsal, lateral, medial, and plantar aspects of the third metatarsal bone in the hind limbs of 6 ponies. The maximal compressive principal strain was approximately -600 X 10(-6) m/m, and exceeded the amplitudes of the tensile strains at all aspects of the bone. After transformation, the shear strain and the principal strains parallel and perpendicular to the bone were obtained. The first peak in the bending strain was higher in the dorsal and lateral aspects, and the second peak was higher in the medial and plantar aspects. Young modulus of elasticity w...