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Background Correct diagnosis and characterisation of deep digital flexor tendon (DDFT) lesions in equine athletes allows targeted treatment and improved prognostication. Objectives To assess the prevalence and character of pathological change within the DDFT in the pastern with concurrent tendon injury distally. It is hypothesised that tendon lesions in the pastern will be associated with tendinopathy within the hoof capsule. Study design Retrospective descriptive case series. Methods Cases with DDFT lesions in the pastern and magnetic resonance imaging (MRI) or ultrasonography of the foot were evaluated retrospectively. Lesion location and type were recorded. Odds ratios were calculated to determine the associations between more distal tendinopathy and the presence of different DDFT lesion types in the pastern. Results Thirty-four MRI scans of 33 horses and 64 ultrasonographic exams of 58 horses were analysed. Lesion location and type were recorded. Distal DDFT lesions were found in 75% (95% CI: 66.0-84.0) of total cases of pastern DDF tendinopathy and in 97% (95% CI: 91.6-100.0) of cases with core lesions of the DDFT in the pastern. A core lesion in the pastern was significantly more likely (OR = 20.7, 95% CI: 2.2-191.0; P = .008) to be associated with injury in the foot than other types of pastern lesion. Main limitations MRIs of the foot were not obtained on all included limbs which did not allow for fully inclusive evaluation of DDFT lesions distal to the navicular bone. Conclusions DDFT pathological change in the pastern, particularly core lesions, is associated with additional tendinopathy within the hoof capsule. When a DDFT lesion is found in the pastern, further imaging of the tendon within the foot is indicated to direct appropriate treatment and improve prognostication.

The purpose of this study was to describe normal magnetic resonance imaging and computed tomographic anatomy of pastern and coffin joints in Egyptian buffalo using cadaveric distal limbs. This study was achieved using twelve fresh cadaveric distal limbs from adult healthy buffaloes of both sexes. These cadaveric limbs were scanned using a 1 Tesla MRI scanner and CT scanner, injected with red latex, frozen at -20°C for 1 week, and then sectioned into sagittal, dorsal and transverse slices. The obtained MR and CT images were selected to be matched with their corresponding anatomical cross-sections for identification and evaluation of the clinically correlated anatomical structures of the pastern and coffin joints. The difference in signal intensities on CT and MRI scans amongst the tissues allowed clear differentiation of major bone and soft tissue structures of the pastern and coffin joints. CT provided a high spatial resolution of bone and soft tissue structures, however, MRI allowed a better and higher resolution and definition between soft tissues. The current study provided a normal CT and MRI anatomic reference which could help veterinary clinicians for interpretation and diagnosis of the clinically affected pastern and coffin joints in buffalo.

Working equids rely on sound, balanced hooves, but data describing the typical morphology of the legs and feet of working donkeys are currently lacking. To address this gap in knowledge, the front and hind feet of twenty healthy working donkeys were measured and compared. Hoof width, weight-bearing lengths, heel width, dorsal hoof wall length and lateral and medial heel length of the hoof wall were determined, as well as toe angle, heel angle, hoof pastern axis, coronary band angle and a measure of 'ground surface size'. Viewed from the ground surface of the foot, front feet were more rounded and significantly larger than hind feet. Measures of medial-lateral balance and toe-heel angle ratio were within the recommended healthy guidelines for horses. Hoof pastern axis was broken forward for the studied animals, which supports previous research suggesting that a broken forward hoof pastern axis is normal for donkeys, although further study would be required to confirm whether this conformation is natural. Significant correlations were found between estimated body mass and hoof width in both the front and hind feet. These measurements provide valuable insight into the relationship between hoof and body characteristics, which may aid the development of guidelines for the trimming and management of working donkey hooves. Further study is, however, advised to confirm natural hoof conformation.

The present study aimed to describe the normal cross sectional anatomy and magnetic resonance imaging of pastern and coffin joints in dromedary camel. This study was conducted on twelve distal limbs (fore and hind) of fresh cadavers from three adult camels of both sexes. The specimens appeared normal without orthopedic disorders. Twelve distal limbs were scanned using a 1 Tesla MRI scanner and then injected with colored latex to be sectioned into sagittal, dorsal and transverse slices. Cross anatomical sections were matched with their corresponding MR images for identification and evaluation of the clinically relevant anatomical structures that appeared with different signal intensities on MRI scans. The present study showed that all major soft tissues in pastern and coffin joints of camel were clearly depicted on MR images, however, the palmar/plantar ligaments of pastern joint and ligaments of navicular cartilage could not be identified on MR images. The annotated cross anatomical sections with the corresponding MR images could be used as a normal reference for interpretation of some clinical diseases in pastern and coffin joints of camel.

The present study was designed to provide a descriptive imaging database of the anatomic features of the digit of normal donkeys using ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI) as a means to improve diagnosis and clinical decision-making regarding digit lameness in donkeys. Ten healthy donkeys with sound limbs were assigned for US examination of the digit in each forelimb. In addition, five donkey’s forelimb digit cadavers were subjected for CT and MRI examination. The donkey's digit was divided into three regions: fetlock, pastern, and foot. For evaluation of the digit, longitudinal and transverse US images were obtained. In CT evaluation, three plans were taken: axial, sagittal, and coronal. Whereas, in MRI evaluation, two plans were taken: axial and sagittal with two sequences, T1 and proton density. All US, CT, and MRI images of the donkey's digit were labeled and serially interpret using correlated anatomic cross-sections and references. There was a full description and proper differentiation of the anatomical features of the digit bony (distal third of cannon bone [MCIII], proximal sesamoid bones, phalanges, navicular bone, and digital cushion) and soft tissue structures (superficial digital flexor tendon, deep digital flexor tendon, suspensory ligament, intersesamoidean ligament, straight distal sesamoidean ligament, common digital extensor tendon, annular ligament, and fetlock joint capsule) on US, CT, and MRI images. In conclusion, US, CT, and MRI provide a useful noninvasive method for evaluation of the digit and give a well-defined baseline reference images for the donkey's digit for educational, research, and radiologic purposes.

It is necessary to determine through the correlation variability the direction of changes in the relationship between the signs of the exterior and milk yield in the process of age development of bulls and their daughters. Type traits of four age groups of 45 bulls taken at different periods of their life (12, 16, 18, 24, 36, 48 months), their daughters in the first lactation (8366 heads) were analyzed and founded relationship between the measurements of father - daughter and economically useful traits. Young bulls at the age of 7.2 years from the group (5 to 9 years) are the best in all measurements in all evaluation age periods the estimates exterior compared to other groups. High and reliable relationships were found for stature, body depth, girth of pastern and selectively for other measurements of bulls taken at different measurement times, which gives the right to predict the body type of animals during ontogenesis. Calculated 92 correlation coefficient of measurements of bulls and the same of daughters, as well as their milk yield, taking into account the age of the manufacturer and the date of measurement. Reliable correlation coefficients were obtained from the stature and body depth in bulls of different ages. The relationship measurements of a body of bulls with milk yield of their daughters in most cases low, but reliable (as a large number of daughters). Milk yield of daughters for 305 days of lactation significantly correlates with their body depth and girth of pastern 0,428*** and 0,307***. The relationship between mother and daughter on a number of exterior features is established. The largest - milk yield with stature 0,153 **, body depth 0,173 **, girth behind the shoulder blades 0,154 **, slanting body length 0,157 **. For daughters, milk yield for 305 days of lactation reliably correlates with their body depth and girth behind the shoulder blades 0.428 *** and 0.307 ***. The measurement of the body depth has been established: the body depth bull - daughters 0.156 **; body depth mother - daughter 0,707 **; body depth daughters with a yield 0.428 **; the body depth of bull with daughters milk yield 0.173 **.

Background Fractures of the proximal phalanx are one of the most common long bone fractures of Thoroughbred racehorses. Although the degree of disruption and damage to the articular surface is generally considered a major prognostic determinant, associated arthroscopic findings have not previously been reported. Objectives To describe the metacarpo/metatarsophalangeal (MCP/MTP) joint lesions associated with parasagittal fractures of the proximal phalanx arthroscopically identified at the time of fracture repair and compare radiographic and arthroscopic appearance of complete fractures. Study design Retrospective case series. Methods Case records and arthroscopic images of horses with parasagittal fractures of the proximal phalanx admitted to Newmarket Equine Hospital from 2007 to 2017 were analysed. Results 81 MCP/MTP joints in 78 horses underwent arthroscopic evaluation concurrent to parasagittal fracture repair. Tears of the joint capsule and dorsal synovial plica were noted in 43 cases. Arthroscopy identified articular incongruity in three horses where fracture displacement was not predicted at all on pre-operative radiographs, and incongruity in additional plane(s) to the radiographic displacement in 14 horses. Concurrent osteochondral fragmentation and disruption of cartilage were present in some cases. Main limitations As a retrospective study, the arthroscopic data available for review were variable. Arthroscopic assessment of fracture reduction and joint congruency was evaluated in all cases but there was variation in the completeness of evaluation of the entire dorsal joint space of the fetlock joint. This may have led to the underestimation of soft tissue lesions in these cases. Conclusions Some horses suffering from parasagittal proximal phalanx fractures have concurrent tearing of the joint capsule and/or dorsal plica, which may have relevance in the acute course of events resulting in the development of fractures. Fracture displacement and incongruency at the articular surface cannot confidently be excluded pre-operatively by radiographs alone.

The objective of the current study was to describe the structures of the pastern and coffin joints in dromedary camel using x-ray, bone and soft tissue windows computed tomography (CT) and three-dimensional volume rendering (3DVR) of CT imaging. 3DVR of CT was obtained at the slight flexed dorsal view, plantar view, dorsolateral view and lateral view which explained all the surfaces and structures of the digit bony parts even the parts of the articular surface. The processed images of 3DVR of CT showed different patterns of the cortical, cancellous, subchondral bones and medullary cavity of the bones of the digits. The present study showed clearly all the hard and soft tissues in the pastern and coffin joints of the camel in CT images; however, the plantar ligaments of the pastern joint and ligaments of the navicular cartilage identified on CT images. The CT soft tissue window visualized the joint cavity and their pouches and tendon sheath of the flexor tendons better than the bone window CT. The radiographic, CT and 3D images could be used as a normal reference for the interpretation of some clinical diseases in the pastern and coffin joints of the camel.

Feet and legs of replacement females were objectively evaluated at selection, i.e., approximately 150 d of age (n = 319) and post first parity, i.e., any time after weaning of first litter and before second parturition (n = 277) to 1) compare feet and leg joint angle ranges between selection and post first parity; 2) identify feet and leg joint angle differences between selection and first 3 wk of second gestation; 3) identify feet and leg joint angle differences between farms and gestation days during second gestation; and 4) obtain genetic variance components for conformation angles for the two time points measured. Angles for carpal joint (knee), metacarpophalangeal joint (front pastern), metatarsophalangeal joint (rear pastern), tarsal joint (hock), and rear stance were measured using image analysis software. Between selection and post first parity, significant differences were observed for all joints measured (P < 0.05). Knee, front and rear pastern angles were less (more flexion), and hock angles were greater (less flexion) as age progressed (P < 0.05), while the rear stance pattern was less (feet further under center) at selection than post first parity (only including measures during first 3 wk of second gestation). Only using post first parity leg conformation information, farm was a significant source of variation for front and rear pasterns and rear stance angle measurements (P < 0.05). Knee angle was less (more flexion; P < 0.05) as gestation age progressed. Heritability estimates were low to moderate (0.04–0.35) for all traits measured across time points. Genetic correlations between the same joints at different time points were high (>0.8) between the front leg joints and low (

Summary Avulsion of the proximal attachment of the proximal digital annular ligament (PDAL) was identified in five horses based on characteristic radiographic findings and supported by ultrasonographic examination in four horses. In two cases, PDAL avulsion was associated with acute onset lameness based on physical examination (both animals) and diagnostic analgesia (one animal), and was the only lesion identified. Both horses became sound after a period of rest. Radiographs repeated 11 years later in one animal showed minimal change in the appearance of the lesion. PDAL avulsion was associated with a substantial tear of the deep digital flexor tendon in another horse and in the remaining two cases PDAL avulsion was not associated with lameness. A dissection study found that the proximodistal extent of the proximal PDAL attachment, expressed as a proportion of the length of the proximal phalanx, was significantly (P = 0.011) greater in hindlimbs (11.48 ± 1.01%) compared with forelimbs (8.55 ± 1.06%). This finding may explain why hindlimbs appear at greater risk of PDAL avulsion. In conclusion, while PDAL avulsion can be a cause of acute lameness which, in uncomplicated cases, responds to rest, it can also be an incidental radiographic finding.

A five-year-old Holstein bull became lame after dismount during semen collection. Swelling of the pastern of the left front limb was noted. Radiographic images showed biaxial hyperflexion of the proximal interphalangeal joints in digits III/IV without hyperextension of the metacarpophalangeal joint. Conservative management (stall confinement and NSAIDs) failed to resolve the lameness. External coaptation to stabilise the joint failed to prevent hyperflexion of the joint within the cast and to improve comfort. Pressure sores developed after seven days. Surgical arthrodesis of the PIP joint was performed on each digit by application of a locking compression plate. The bull healed and arthrodesis of the joints progressed over the next 16 weeks. At that time, the bull was walking sound and was returned to semen collection. One year after surgery, the attending veterinarian reported that the bull remained sound at a walk and was still being used for semen collection.

The research was conducted on 10 stallions and 31 mares of the Lipizzaner breed in the stud “Vucijak” Prnjavor. In general, 28 morphometric measures of stallions and mares were taken. Morphometric characterization shows that the “Vucijak” stud farm owns Lipizzaner with smaller body form comparing to other Lipizzaner around Europe. The body of the Lipizzaner from “Vucijak” has a rectangle shape which is in acBcordance with the appearance of the majority of Lipizzaner in Europe. Based on these measures, it is confirmed that there is a statistically significant difference between stallions and mares in: withers height, width of lower jaw, length of neck and shoulders, length of radius, width of chest, length and width of pelvis, volume of front leg tibia, and length of hind leg long pastern (proximal phalanx). Out of all named, in comparison to stallions, mares have bigger morphometric measures of length of shoulders, width of pelvis and length of hind leg long pastern (proximal phalanx). In the remaining 18 measures stallions and mares of the “Vucijak” stud show certain homogeny.

Alteration of limb sensitivity is forbidden in equine sports but difficult to enforce. We aimed to develop an objective field method to assess mechanical nociceptive threshold (MNT) in endurance horses.A remotely controlled pneumatic actuator (1 mm tip) was used to measure forelimb pastern MNT in 108 endurance horses.Median (IQR) MNT at rest was 1.9 N (0.9-3.5). Icing had no significant effect on limb sensitivity. MNT measured at weekly intervals increased from week 1 (1.2 N (0.6-1.8)) to week 3 (1.9 N (1.2-2.8)) (P0.05). In 17 horses without impaired sensitivity, MNT increased from 1.2 N (0.6-2.3) before to 2.4 N (1.2-5.2) after racing (P=0.0017). In desensitised horses, MNT after racing was higher (8 limbs-23.1 N (21.4 to25)) than in horses without impaired sensitivity (42 limbs-2.2 N (1.2-4.3)) (P0.0001). Desensitisation with mepivacaine increased MNT to above the safety cut-off (25 N) at 10 minutes; sensitivity return to baseline varied between individuals but was restored by 330 minutes. None of the horses became averse to the technique.MNT was practical, non-traumatic, repeatable and well tolerated under field conditions in endurance horses. The technique differentiated postracing MNT in horses with normal sensitivity from those with impaired sensitivity.

Summary Limited information exists on distribution of local anaesthetic solution following palmar digital nerve blocks. The aim of this study was to demonstrate potential distribution of local anaesthetic solution following perineural injection of the palmar digital nerves using 2 different volumes of contrast medium and 2 different injections sites. Twelve mature horses were used. Perineural injection of the palmar digital nerves were performed at the level of or 2 cm proximal to the proximal aspect of the ipsilateral ungular cartilage, using 1.5 or 2.5 ml radiopaque contrast medium. In total, 96 injections were performed. Four standard radiographic views of the pastern were obtained immediately after injections and 10 and 20 min later. Images were analysed subjectively and objectively. After distal injections, the contrast medium was more localised around the injection site; after proximal injections the contrast patch had greater proximal–distal length. The greatest proximal diffusion was to 31.7% of the length of the proximal phalanx (from the level of the proximal interphalangeal joint) after distal injections and to 70% after proximal injections. The larger volume resulted in significantly greater proximal diffusion than the smaller volume at the distal, but not at the proximal injection site (P

Reasons for performing study: Digital hypothermia may be effective for laminitis prophylaxis and therapy, but the efficacy of cooling methods used in clinical practice requires evaluation. Objectives: To use hoof wall surface temperature (HWST) to compare several cooling methods used in clinical practice. Study design: Experimental crossover design with a minimum washout period of 72 h. Methods: Seven cooling methods (commercially available ice packs, wraps and boots) and one prototypical dry-sleeve device were applied to a single forelimb in 4 horses for 8h, during which HWST of the cooled forelimb and the uncooled (control) forelimb was recorded hourly. Results were analysed descriptively. Results: The median (range) HWST from 2-8h was lowest for the ice and water immersion methods that included the foot and extended proximally to at least include the pastern: 5.2°C (range: 4.8-7.8°C) for the fluid bag and 2.7°C (2.4-3.4°C) for the ice boot. An ice boot that included the distal limb but not the foot resulted in a median HWST of 25.7°C (20.6-27.2°C). Dry interface applications (ice packs) confined to the foot only resulted in a median HWST of 21.5°C (19.5-25.5°C) for the coronet sleeve and 19.8°C (17.6-23°C) for a commercial ice pack. For the dry interface applications that included the foot and distal limb, the median HWST was much higher for the ice pack device, 19.9°C (18.7-23.1°C), compared with the perfused cuff prototype of 5.4°C (4.2-7°C). Conclusions: Immersion of the foot and at least the pastern region in ice and water achieved sustained HWST

The objective was to compare the degree of cartilage destruction obtained with three different drilling techniques for minimally invasive arthrodesis of the equine pastern joint. Three drilling techniques were randomly tested on 36 cadaver distal limbs (six front and six hind limbs in each group). The basic drilling pattern consisted of several passes in a dorsopalmar and/or plantar direction across the joint space (group 1) and was either supplemented with one additional pass in a lateromedial and/or mediolateral direction (group 2) or two additional passes in a distodorsal–proximopalmar and/or plantar direction (group 3). After drilling, the pastern joints were disarticulated, the articular surfaces of P1 and P2 were digitally photographed, and the area of removed cartilage was measured using planimetry. The mean percentage of cartilage removed in the entire pastern joint was significantly lower in group 1 (34.1 ± 4.0%) compared with groups 2 and 3 (45.0 ± 5.2% and 43.0 ± 4.0%, respectively; P < .001). There was significantly more cartilage removed in the hind (47.1 ± 4.4%) versus the forelimbs (42.0 ± 5.0%) of group 2 (P = .003), whereas in group 3, there was significantly more cartilage removed in the forelimbs (44.6 ± 3.0%) compared with the hind limbs (40.6 ± 3.0%) (P = .039). The technique of group 2 gave significantly more cartilage destruction compared with technique 1 while being practical to perform. Therefore, this technique seems to be the most promising for further evaluation in a clinical situation.

An 18-month-old warmblood filly was 4/5 lame on the front right limb at referral and showed severe swelling of the right shoulder region and pain during manipulation of the shoulder region. Radiography revealed a roundish 5 × 7 cm radiolucent area with defined borders within the greater tubercle and the presence of a fracture of the lateral tubercle associated with the cyst. Cellular blood count was 27,500 WBC/μL and serum biochemical analyses revealed fibrinogen of 855 mg/dL. The fractured bone was removed surgically; the cyst debrided and filled with autologous cancellous bone graft. Three and five weeks after surgery the filly was reoperated on because of an osseous sequestrum and a periostal defect on the distal dorsolateral aspect of the pastern of the right hind limb and a septic synovitis of the DFTS of the left hind limb. Fifteen month after surgery the filly was not lame and was introduced to training. Unicameral bone cysts (UBC) are well described lesions, often associated to pathologic fracture in the proximal humerus of children but, until present, no scientific report exists of UBC in the foal. The prompt surgical management had a favorable outcome.

The purpose of this study was to create a lower forelimb model of the Thoroughbred horse for measuring the force in the superficial and deep digital flexor tendons (SDFT and DDFT), and the suspensory ligament (SL) during a trot. The mass, centers of gravity, and inertial moments in the metacarpus, pastern, and hoof segments were measured in 4 Thoroughbred horses. The moment arms of the SDFT, DDFT, and SL in the metacarpophalangeal (fetlock) and distal interphalangeal (coffin) joints were measured in 7 Thoroughbred horses. The relationship between the fetlock joint angle and the force in the SL was assessed in 3 limbs of 2 Thoroughbred horses. The forces in the SDFT, DDFT, and SL during a trot were also measured in 7 Thoroughbred horses. The mass of the 3 segments, and the moment arms of the SDFT and DDFT in the fetlock joint of the Thoroughbred horses were smaller than those of the Warmblood horses, whereas the other values were almost the same in the 2 types. The calculated force in the SDFT with this Thoroughbred model reached a peak (4,615 N) at 39.3% of the stance phase, whereas that in the DDFT reached a peak (5,076 N) at 51.2% of the stance phase. The force in the SL reached a peak (11,957 N) at 49.4% of the stance phase. This lower forelimb model of the Thoroughbred can be applied to studying the effects of different shoe types and change of hoof angle for the flexor tendon and SL forces.

Verrucous hemangiomas are a rare specific variant of equine skin tumors not well described in the literature. An 8-year-old gelding presented a unilateral lesion on the pastern. Macroscopically, the mass showed a warty and verrucous surface with focal ulcerations. The histology showed a dermal proliferation of endothelial-layered capillaries and venules separated by a delicate stroma of scant fibroblasts and collagen deposition, with pseudoepitheliomatous hyperplasia (exuberant reactive irregular epithelial hyperplasia with tongue-like projections extending into the dermis, mimicking downgrowth of squamous cell carcinoma) and orthokeratotic hyperkeratosis of the overlying epidermis. The immunohistochemical study confirmed the endothelial origin of the tumor, and a final diagnosis of verrucous hemangioma with pseudoepitheliomatous hyperplasia was confirmed. To the knowledge of the authors, this is the first detailed description of this entity in adult horses. Moreover, the clinical progression and epidermal changes have not been previously reported, emphasizing the importance of a pathological study of any epithelial preneoplastic lesion to rule out an underlying dermal neoplasia.

The work describes and compares the conformation traits and gait characteristics in the main native Iberian dressage Purebreds (Lusitano, Spanish and Menorca horses). In total, 4 strides belonging to each of 66 males (4-14 years old) were recorded at handled trot, using a 3D semi-automatic movement analysis system. Principal component analysis (PCA) and intraclass Correlations (iC) were computed. The Menorca Purebred showed proportionally higher limbs (23.8 and 15.1cm for the forelimb cannon and pastern lengths), the Lusitano Purebred had larger inclinations (66.1°, 37.7° and 47.9° for the scapula and pastern angles), and the Spanish Purebred presented a longer scapula (41.5 cm) and a larger hip angle (132.1°), apparently showing a better conformation for dressage gaits. However, the three breeds presented undesirable tarsus joint conformation (155.5°) for dressage performance. In general, all of them showed good features in the kinematics of the forelimbs. Nevertheless, the functional capacity of their hindlimbs and linear parameters probably need to be improved for their competitiveness.

This study aimed to evaluate, through biometry, the forelimb hoof of horses participating in show jumping, barrel, long rope and polo competitions. Thirty subjects were assessed in relation to each competition (total of 120 animals). The linear measurements (cm) included the dorsal length of the toe; medial and lateral lengths of the quarter; medial and lateral heights of the quarter; lateral and medial lengths of the heel; medial and lateral heights of the heel; hoof length; hoof width; frog length; and frog width. The following angles (°) were measured: toe angle, pastern angle, heel angle and shoulder palette. The length of the horseshoe, coronet circumference and body weight were also assessed. With the use of hoof biometric evaluation was possible to identify the imbalances of forelimb in athletic horses and the most common were broken-backward hoof angle, with 96.7% of the animals showing this in the right forelimb (RFL) and 95.8% in the left forelimb (LFL); and contracted heels, with 95.0% in the RFL and 87.6% in the LFL. The competition type in which greatest numbers of hoof balance abnormalities were shown was the long rope, followed by the barrel. There were high frequencies of medial/lateral imbalance in all the sports. We conclude that animals used in functional tests have a high incidence of hoof balance abnormalities in the forelimbs. Objetivou-se avaliar, através da biometria, os cascos dos membros anteriores de equinos participantes de provas de Hipismo Clássico, Tambor, Laço Comprido e Pólo. Em cada modalidade foram avaliados 30 indivíduos totalizando 120 animais. As mensurações lineares (cm) incluíram o comprimento dorsal da pinça, comprimentos lateral e medial dos quartos, altura medial e lateral dos quartos, comprimento lateral e medial dos talões, alturas lateral e medial dos talões, comprimento do casco, largura do casco, comprimento da ranilha, largura da ranilha, e as angulares (graus) foram relativas ao ângulo do casco medido pela pinça (podogoniometria), ângulo da quartela, ângulo dos talões, ângulo das paletas. O comprimento da ferradura, circunferência da coroa do casco e peso corporal também foram avaliados. Através da biometria do casco foi possível avaliar os desequilíbrios do membro anterior de animais atletas e os mais comuns foram: quebra do eixo podal, com 96,7% dos animais apresentando essa alteração no membro torácico direito (MTD) e 95,8% no membro torácico esquerdo (MTE); talões contraídos com 95,0% no MTD e 87,6% no MTE. A modalidade com os maiores desequilíbrios foi a de Laço Comprido, seguida pelos animais de Tambor. Foi encontrada uma alta frequência de desequilíbrio médio lateral em todas as modalidades desportivas. Conclui-se que animais utilizados em provas funcionais apresentam uma alta incidência de desequilíbrios podal nos membros torácicos.

This paper describes the handled walking and trotting kinematics (linear, temporal, and angular traits) of 35 Menorca Purebred (MEN) stallions, and the relationships among these variables is presented for the first time, along with a discussion of the influence of the hind limb pastern angle on kinematic variables at both gaits. For data collection, all animals, aged between 3 and 10 years old and belonging to 28 different studs, were recorded under the same experimental and environmental conditions, using a three-dimensional (3D) semiautomatic movement analysis system. A total of 24 kinematic variables (temporal, linear, and angular) at the walk and the trot and a morphometric variable measured at the mid stance position of walking (hind pastern angle) were included in this analysis. Angle-time diagrams of the hind pastern angle while walking and trotting normalized to stride duration were also obtained. Generally the MEN stallions' forelimb movements closely resembled the movement characteristics of other European dressage performance breeds, while the hind limb locomotion showed a greater likeness to Iberian dressage Purebreds. Despite this, their ability in collection and propulsion at the walk and the trot was relatively low. The hind limb pastern conformation was partially connected to the hind limb movements for both gaits, with an apparently negative effect of excessively upright pasterns on the amplitude at the trot, which indirectly reduced collection ability.

An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infections in horses in Sweden raised questions concerning the risk posed by horses to their surroundings following MRSA infections. This initiated a longitudinal study to investigate how long MRSA-infected horses remained positive and to test the sensitivity of different anatomical sampling sites for detection of MRSA. Between October 2008 and June 2010, 9 of 15 horses notified as having MRSA-infected wounds fitted the case criteria for the study. The cases were sampled at five anatomical sites (nostrils, corner of mouth, pastern, perineum, and previous infection site) on six to seven occasions or more during approximately 12–18 months. MRSA-specific broth and agar were used for culture. Verified MRSA isolates were spa -typed. The sensitivity of sampling sites was calculated. The most sensitive sampling site was the nostrils, with a sensitivity of 0.91 (95% CI: 0.59–1.00). The other test sites had a sensitivity of 0–0.09. Individual cases tested positive, but with time all tested negative. The observed carriage time ranged from 55 to 711 days (median = 143, IQR: 111–172 days), but these data should be interpreted with caution since only a small number of cases were studied.

Deep digital flexor (DDF) tenotomy is a technique employed for years to treat selected disorders of the musculoskeletal system in horses. Although two different surgical approaches (i.e. mid-metacarpal and pastern) have been described for performing the procedure, in vitro quantitative data regarding the modifications induced by either technique on the distal articular angles is lacking. Therefore, the purpose of the study reported here was to investigate the viability of a proposed biomechanical system of induced-traction used to compare the two DDF tenotomy techniques by measuring the distal articular angles of equine cadaver forelimbs. Ten pairs of forelimbs were collected and mounted to a biomechanical system developed to apply traction at the toe level. Dorsal articular angles of the metacarpophalangeal (MP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints were determined by geometric lines on radiographs taken before and after performing each technique. Comparisons between each tenotomy group and its own control, for each joint, and between the two tenotomy groups using as variable the difference between the tenotomy and control groups were tested. Despite the lack of statistical significance, the DDF tenotomy technique at the pastern level produced extension, to a lesser and greater extent, of the PIP and DIP joints, respectively when compared to the mid-metacarpal level. No remarkable differences could be observed for the MP joint. The developed traction-induced biomechanical construct seemed to be effective in producing valuable quantitative estimations of the distal articular angles of equine cadaver forelimbs subjected to different DDF tenotomy techniques.

Summary The suspensory apparatus is composed of the third interosseous muscle (TIOM) or suspensory ligament, the proximal sesamoid bones, palmar ligament and distal sesamoidean ligaments (DSL). Of these structures, the suspensory ligament is the most frequently implicated in conditions seen in race and sport horses; nevertheless, DSL lesions are not rare and often associated with other injuries that can modify patient prognosis and management. Ultrasonography has been shown to be valuable in the assessment of DSL desmitis. In contrast to the metacarpal area, the pastern region has been considered technically more difficult to scan because of the small and irregular contact surface and frequent artefacts. Advances in imaging techniques with adapted ultrasound probes and the use of magnetic resonance imaging (MRI) for equine lameness evaluation have revealed that distal sesamoidean ligament injuries are more frequently implicated in lameness than previously suspected.

Summary Ultrasonography is the technique of choice to identify and document tendon and ligament injuries and its interest in the diagnosis of pastern injuries has been largely demonstrated. Ultrasound examination is therefore part of routine examination in diagnostic work-up of lameness originating from the foot or pastern area. This paper describes the ultrasonographic technique and presents normal and abnormal ultrasound images of the palmar pastern. A comprehensive description of normal transverse and longitudinal ultrasound scans is made at 4 anatomical levels. Main ultrasonographic findings indicative of digital flexor tendon lesions are presented as well as digital sheath injuries.

SummaryObjective: To compare four different techniques for synoviocentesis of the equine digital flexor tendon sheath (DFTS).Methods: Fifteen inexperienced operators performed each of the following injection techniques on two cadaveric limbs: Proximal (at the proximal recess of the DFTS), Axial (axial to the proximal sesamoid bone), Base (at the base of the proximal sesamoid bone), and Distal (at the pastern). The number of attempts needed before the needle was assumed to be correctly positioned into the DFTS was recorded and 10 ml of methylene blue was injected. The limbs were dissected to determine the presence of methylene blue in the DFTS, the distance between the needle entrance point and the lateral palmar or plantar (digital) nerve, the degree of subcutaneous leakage and the distance between the border of the leakage zone and the lateral digital nerve.Results: The Axial (29/30) and Distal (25/30) approaches had the highest numbers of successful injections. The median number of attempts was highest for the Axial approach. The distances from the injection point and from the border of the leakage zone to the lateral digital nerve were longer for Distal and Axial approaches.Clinical relevance: In the hands of inexperienced operators, the Axial approach was the most successful technique for injection of the equine DFTS. Sparse subcutaneous leakage and larger distance to the nerve when using this technique might decrease the risk of inadvertent palmar or plantar digital nerve desensitisation when performing DFTS analgesia.

Objective To develop a lameness model to assess the efficacy of analgesics for alleviating pain, swelling and systemic signs of inflammation in sheep. Procedures The response to subcutaneous injection of 0.1 or 0.2 mL turpentine in a forelimb pastern (n = 4 ewes per dose) was examined at 0, 3, 6, 24, 48 and 72 h. In a second experiment, responses were measured at 0, 2, 4, 6, 8, 10, 12 and 24 h in ewes receiving 0.1 mL turpentine ± meloxicam 1 mg/kg IV at 0 h (n = 6 per group). Responses measured included forceplate pressure, skin temperature, limb circumference, nociception, leucocyte count, neutrophil : lymphocyte ratio, haptoglobin and daily feed intake. Results Turpentine injection caused a decrease in weight borne on the treated limb, increased skin temperature, increased sensitivity at the injection site and leucocytosis by 2 h and increased limb circumference by 4 h. Weight borne and sensitivity of the injected limb returned to control levels after around 24 h, whereas tissue swelling, elevated skin temperature and elevated haptoglobin levels persisted for at least 72 h. Treatment with meloxicam improved weight borne by and tolerance to pressure exerted on the turpentine-injected limb. Conclusions The local and systemic signs of inflammation and pain, temporary reduction in function of the affected limb and partial amelioration of some of these changes by the dose of meloxicam used here suggest that injection of turpentine in the lower forelimb provides a suitable model for examining the efficacy of analgesics for alleviation of pain and inflammation in sheep.

Summary Reasons for performing study: No previous study compares computed tomography (CT), contrast-enhanced computed tomography (CECT) and standing low-field magnetic resonance imaging (LFMRI) to detect lesions in horses with lameness localised to the foot. This study will help clinicians understand the limitations of these techniques. Objectives: To determine if CT, CECT and LFMRI would identify lesions within the distal limb and document discrepancies with lesion distribution and lesion classification. Methods: Lesions in specific structures identified on CT and MR images of feet (31 limbs) from the same horse were reviewed and compared. Distributions of lesions were compared using a Chi-squared test and techniques analysed using the paired marginal homogeneity test for concordance. Results: Lesions of the deep digital flexor tendon (DDFT) were most common and CT/CECT identified more lesions than LFMRI. Deep digital flexor tendon lesions seen on LFMRI only were frequently distal to the proximal extent of the distal sesamoid and DDFT lesions seen on CT/CECT only were frequently proximal to the distal sesamoid. Lesions identified on LFMRI only were core (23.3%) or splits (43.3%), whereas lesions identified only on CT were abrasions (29.8%), core (15.8%), enlargement (15.8%) or mineralisation (12.3%). Contrast-enhanced CT improved lesion identification at the DDFT insertion compared to CT and resulted in distal sesamoidean impar ligament and collateral sesamoidean ligament vascular enhancement in 75% of cases. Low-field MRI and CT/CECT failed to identify soft tissue mineralisation and bone oedema, respectively. Conclusions and potential relevance: Multiple lesions are detected with CT, CECT and LFMRI but there is variability in lesion detection and classification. LFMRI centred only on the podotrochlear apparatus may fail to identify lesions of the pastern or soft tissue mineralisation. Computed tomography may fail to identify DDFT lesions distal to the proximal border of the distal sesamoid.

Summary of Injury Characteristics by Group for 106 Horses with Lacerations of the Digital Flexor Tendons, Suspensory Ligament, and/orDistal Sesamoidean LigamentsStructuresAffected (n=106)Total(n=106)Limb Region(n=106)OpenTendon Sheathn=61 (58%)SuturedTendonn=58 (55%)Casting (n=104)FetlockHyperextensionSDFT DDFT SL/DSL Pr M D Pa (n=15)wNumber ofHorses (n=84)Period (Weeks)Median [Range]Group 1 60 (57%) 36 24 41 (68% ofGroup 1)4.7 [1–12] 1P x x 27 1 8 13 5 13 9 18 4.8 [2–12]zP P x 13 1 1 4 7 9 9 10 6.2 [1.5–12]x P x 10 10 9 2 7 4.3 [3–7] 1x x P 7 1 5 1 2 3 4 1.75 [1–2]PP P 2 11 2 1 1 2Px P 1 1 1 1 6Group 2 46 (43%) 25 34 43 (98% ofGroup 2)7 [0.5–14] 14TP x 17 3842 7 12 15 6.7 [0.5–14] 3T T x 10 1 5 4 5 9 10 8.5 [4–10] 4T T P 6 2 1 2 1 4 6 6 7 [1–11] 4T x x 4 1 3 3 2 4 6 [4–8]TP P 2 1 1 2 2 6z 1T T T 2 2 2 1 2 6 [4–8] 1Tx P 1 1 1 1 12 1PT P 1 1 1 1 2PT x 1 1 1xT T 1 1 1 1 2xT x 1 1 1 1 1 6Group 1, horses with partial transection of 1 or more tendons or ligaments (SDFT, DDFT, SL, and DSL).Group 2, horses with complete transection of 1 or more tendons or ligaments (SDFT, DDFT, SL, and DSL). In 2 cases, suturing or cast application was not recorded.wIn 11 horses, the information on fetlock hyperextension was not available.zIn 2 horses, the information for casting period was not available.SDFT, superficial digital flexor tendon; DDFT, deep digital flexor tendon; SL, suspensory ligament; DSL, distal sesamoidean ligaments; P, partialtransection of a tendon or a ligament; T, total transection of a tendon or a ligament; x, tendon or ligament not affected; Pr, proximal third of meta-carpus/metatarsus; M, middle third of metacarpus/metatarsus; D, distal third of metacarpus/metatarsus; Pa, pastern.

Summary An 11-year-old Thoroughbred gelding was presented for lameness investigation following acute onset hindlimb lameness, which developed during a period of paddock turnout. Clinical examination revealed a swelling over the dorsolateral aspect of the pastern that was painful on digital palpation. Radiography of this area was consistent with an aggressive bone lesion involving both joint surfaces of the middle phalanx with pathological fracture and distal collapse of this bone. On this basis, the horse was subjected to euthanasia. Post mortem histopathological examination revealed presence of an osteosarcoma without involvement of the articular cartilage. This bone tumour is extremely rare in horses and has not been reported in this anatomical location.

High speed cinematography was used to measure the timing and distance characteristics of the trot in five sound horses. Two farriery treatments were compared: (1) normal, in which the dorsal hoof wall was aligned with the pastern axis in all four feet and (2) acute hind hoof angulation, in which the hind toes were allowed to grow relatively longer than the heels, so that the angulation was approximately 10 degrees lower than the normal hind hoof angle for the individual animal. Comparison between the two treatments showed that the acute hind hoof angulation was associated with significant increases in hind limb breakover time (P = 0.001), overreach distance (P = 0.001) and overreach duration (P = 0.017), whereas stride length, forelimb breakover and diagonal distance did not change (P > 0.05). In the majority of horses, limb movements at the start and end of the diagonal stance phase were slightly asynchronous, so that when the hooves were trimmed normally the hind limb more often preceded the diagonal forelimb at impact and lift off. The prolongation of hind limb breakover due to the acute hind hoof angulation was associated with a tendency for the hind limb to lift off later than the forelimb. The difference in lift off sequence between the two farriery treatments was highly significant (P = 0.001). During the swing phase the normal coordination was restored and there was no significant difference in the impact sequence with the normal and acute hind hoof angulations (P > 0.05).

The angulation of the equine fetlock determines the load of associated tendons and probably their predisposition for injuries. However, it is questionable how the individual toe conformation and tendon properties interact with the dorsal metacarpophalangeal joint angle (DMPJ). Data are needed for a tangible evaluation of the equine limb conformation for more specific orthopaedic treatment. The aim was to evaluate the correlation between the DMPJ, toe conformation and cross-sectional area (CSA) of both flexor tendons; the superficial digital flexor tendon (SDFT) and deep digital flexor tendon (DDFT). Thirty Warmblood horses were available for the study. Lateromedial radiographs of the toe and fetlock and transverse ultrasound images of both flexor tendons were obtained from three zones. The DMPJ, length and angle of the phalanges and CSA SDFT/DDFT were measured. In addition, hoof angle, wither height, age, and sex were documented. Correlations were calculated using Pearson’s test. A paired t-test was used to evaluate left–right differences. Length and angle of the proximal and middle phalanx were significantly associated with the DMPJ (r = -0.28 – -0.45, p

Summary Analgesia usually occurs within 5 min after administration of local anaesthetic solution into joints or around nerves in the distal portion of the limb. Gait should be assessed within 10 min after diagnostic regional analgesia of the distal portion of the limb because rapid diffusion of anaesthetic solution can result in anaesthesia of other nerve branches, thus confusing results of the examination. A palmar digital nerve block (PDNB) anaesthetises most of the foot, including the distal interphalangeal (DIP) joint (coffin joint), rather than just the palmar half of the foot, as was once commonly believed. To avoid partially anaesthetising the proximal interphalangeal joint (pastern joint), the palmar digital nerves should be anaesthetised near or distal to the proximal margin of the collateral cartilages. Clinicians should be aware that an abaxial sesamoid nerve block (ASNB) may ameliorate or abolish pain within the metacarpo/metatarso-phalangeal joint (fetlock joint). Mepivacaine administered into the DIP joint desensitises the DIP joint and probably the palmar digital nerves to also cause anaesthesia of the navicular bursa, the navicular bone, the toe region of the sole, the digital portion of the deep digital flexor tendon (DDFT) and the distal portions of the collateral ligaments of the DIP joint. When a large volume of mepivacaine HCl (e.g. 10 ml) is administered, the heel region of the sole may also be desensitised. Only a small percentage of horses with disease of the collateral ligament(s) of the DIP joint show a significant improvement in lameness after intra-articular analgesia of the DIP joint, and no horse is likely to improve after intrabursal analgesia of the navicular bursa. A PDNB, however, improves lameness substantially in most horses that are lame because of disease of the collateral ligament(s) of the DIP joint, and all affected horses are likely to become sound after an abaxial sesamoid nerve block. The degree of improvement in lameness associated with injury to one or both collateral ligaments of the DIP joint after PDNB is determined by the extent of the injury and the level at which the palmar digital nerves are anaesthetised. The further proximal the level of the injury within the collateral ligament, the less likely that lameness is ameliorated by analgesia of the DIP joint or a PDNB. Verschooten's technique appears to be the most accurate technique for centesis of the navicular bursa. Even though analgesia of the DIP joint results in analgesia of the navicular bursa, analgesia of the navicular bursa does not result in analgesia of the DIP joint. Pain arising from the DIP joint can probably be excluded as a cause of lameness when lameness is attenuated by analgesia of the navicular bursa. Analgesia of the digital flexor tendon sheath (DFTS) is likely to desensitise only structures that are contained within or border on the sheath itself (i.e. the superficial and deep digital flexor tendons, the straight and oblique distal sesamoidean ligaments, the annular ligaments of the fetlock and pastern, and the portion of the DDFT that lies within the foot). Because lameness caused by disease of the DDFT within the foot may fail to improve appreciably after analgesia of the palmar digital nerves, the DIP joint, or the navicular bursa, a portion of the DDFT within the foot and distal to the DFTS probably receives its sensory supply from more proximal deep branches of the medial and lateral palmar digital nerves that enter the DFTS. Performing intrathecal analgesia of the DFTS on horses with lameness that is unchanged after anaesthesia of the palmar digital nerves but resolves after an ASNB, may be useful in localising lameness to that portion of the DDFT that lies within the foot. Resolution of lameness after intrathecal analgesia of the DFTS justifies suspicion of a lesion within the digital portion of the DDFT or within structures contained within the DFTS. The belief that concurrent or sequential intra-articular administration of medication substantially increases the risk of joint infection or that inflammation caused by the local anaesthetic solution may dampen the therapeutic response to intra-articular medication appears to be unfounded.

Summary Reasons for performing study: There is little information available to define conformational changes with age using an objective but practical method of recording specific body measurements. Objective: To analyse conformation objectively in a population of racing Thoroughbreds and describe the changes from weanling to age 3 years. Methods: Annual photographs were taken over 4 years and conformation measurements made from photographs using specific reference points marked on the horses. Results: Correlation analysis revealed highly significant, moderate to strong relationships between long bone lengths and wither height for all ages. All long bone lengths showed moderate to strong relationships with each other for all ages. The front and rear pastern angles were significantly correlated with the angle of the dorsal surface of the front and rear hooves, respectively, for all. Wither height, croup height and length of neck topline, neck bottomline, scapula, humerus, radius and femur increased significantly from age 0–1 year and age 1–2 years. Hoof lengths (medial and lateral, right and left) grew significantly between the ages of 0 and 1 and 1 and 2 years, but decreased in length between age 2 and 3 years. Horses became more offset in the right limb between weanling and age 3 years, but the offset ratios did not change with age on the left limb. The angle of the scapula (I), shoulder and radiometacarpus significantly increased between all age groups (became more upright). The angle of the dorsal surface of the hooves (both front and hind) decreased significantly from ages 0 to 1 and 1 to 2 years, but showed no significant difference between ages 2 and 3 years. Conclusions: A strong relationship between long bone lengths and wither height for all ages supports the theory that horses are proportional. Longitudinal bone growth in the distal limb increased only 5–7% from weanling to age 3 years and is presumably completed prior to the yearling year. Several growth measures increased from ages 0 to 1 and 1 to 2 years, but did not increase from age 2–3 years; indicating that growth rate either showed or reached a plateau at this time. Potential relevance: This study provides objective information regarding conformation and skeletal growth in the Thoroughbred which can be utilised for selection and recognition of significant conformational abnormalities.

Objective— To compare the biomechanical characteristics, failure mode, and effects of side (left or right limb) and end (forelimb or hindlimb) of different screws in 2-screw, parallel-screw proximal interphalangeal joint arthrodesis constructs in horses. Study Design— In vitro experimental study. Sample Population— Twenty limbs from 6 cadavers (4 complete limb sets, 2 partial sets—total of 4 forelimb and 6 hindlimb pairs). Methods— Two parallel 5.5 mm cortical (AO) screws were inserted in lag fashion in 1 randomly allocated limb of a pair, and 2 parallel headless, tapered, variable-pitched, titanium compression screws (Acutrak-Plus®) were inserted in the contralateral limb. Constructs were tested in 3-point bending in a dorsopalmar (plantar) direction using a materials-testing machine at a loading rate of 5.83 mm/s. Maximal bending moment at failure and composite stiffness were calculated from data generated on load–displacement curves. Data were analyzed using a Friedman 2-way analysis of variance and Wilcoxon's signed-rank tests. Results— No significant difference was detected for bending moment or stiffness values in proximal interphalangeal joint arthrodesis constructs using 2 parallel Acutrak-Plus® or AO screws for fixation. Mean stiffness values were significantly different between forelimb and hindlimb constructs. Conclusions— Performance of 2 parallel Acutrak-Plus® screws was biomechanically comparable with 2 parallel AO 5.5 mm cortical screws in in vitro pastern arthrodesis constructs. Clinical Relevance— Acutrak-Plus® screws may provide an alternative means of fixation for proximal interphalangeal joint arthrodesis.

OSTEOARTHRITIS The MC/MTPh joint is commonly affected by osteoarthritis (OA) and pathological changes associated with this disease frequently affect P1 and the PSBs. Articular and periarticular osteophytosis is frequently identified radiographically affecting the dorsoproximal margins of P1 and the proximal and distal aspects of the PSB. As always, the presence of osteophytes does not always mean that OA is the cause of lameness, as such changes may just be a historical change of no significance. Both P1 and the PSB are sites for cartilage pathology such as wear lines, and partial and full thickness articular cartilage erosions.

Despite the increasing use of magnetic resonance imaging (MRI), ultrasound remains a valuable tool to diagnose injuries that cause distal extremity lameness in the horse. The key to a successful examination is a strong knowledge of anatomy in combination with proper ultrasonographic technique and the patience and dedication to learn these skills. Similar to all imaging modalities, it is equally important to recognize and consider the limitations of ultrasound in this region so that findings can be interpreted appropriately. Ultrasound can be used to diagnose injuries to the deep digital flexor tendon (DDFT), straight distal sesamoidean ligament and branches of the superficial digital flexor tendon using standard pastern ultrasonographic technique. The addition of newer techniques to image the DDFT at the level of P2, the navicular bursa and the collateral sesamoidean ligament can enhance the diagnostic utility of ultrasound in horses with distal extremity lameness. Although visibility is limited, ultrasound can be used to diagnose collateral ligament injuries of the coffin joint in many affected horses. Transcuneal imaging may be useful in some horses to detect abnormalities of the distal sesamoidean impar ligament and navicular bone, but evaluation of the DDFT is limited. Ultrasound should be considered in all horses with distal extremity lameness, regardless of the ability to perform advanced imaging procedures. Information gained is often complementary to other imaging modalities and may provide the basis for recheck examination purposes.

SummaryOsteoarthritis of the proximal interphalangeal joint (PIPJ) is a common cause of chronic lameness in the horse that requires surgical arthrodesis when medical management is no longer able to alleviate pain. Surgical principles for successful PIPJ arthrodesis include articular cartilage debridement and rigid fixation. To completely debride articular cartilage, the collateral ligaments and extensor tendon are transected, disarticulating the joint. The purpose of this study was to demonstrate that in chronically lame horses with periarticular new-bone formation and osteoarthritis, successful arthrodesis occurs without joint disarticulation and complete articular cartilage debridement. We hypothesised that complete articular debridement is not necessary, thus allowing for a less invasive surgical approach that decreases surgical time and hospitalisation with comparable success rates to previous reports. Medical records from 2000–2007 were reviewed for PIPJ disease. Information regarding lameness, surgical time and hospitalisation were retrieved from 11 horses (12 limbs). Follow-up information was obtained via a telephone interview and a re-evaluation. Average hospital and surgery times were shorter than previous reports at 19 days and 111 minutes respectively. Lameness decreased at least one grade in 92% of limbs. 73% of owners would elect to operate again. The data suggests that successful arthrodesis occurs without joint dis-articulation and complete articular cartilage debridement.

DIAGNOSTIC ultrasonography for the musculoskeletal system in the horse was first used in the early 1980s. Initial applications were directed towards the diagnosis of flexor tendon and ligament injuries in the distal limb, but this modality is now commonly indicated for the assessment of the stifle, hock, fetlock, carpus, pastern and coffin joints. This article describes the use of diagnostic ultrasound in horses to examine these joints, as well as muscle and bone, outlining normal versus pathological findings in each case. While this imaging technique may also be employed to examine the shoulder, hip, cervical facet and temporomandibular joints, the indications are less frequent and, hence, are not discussed in this article. In all cases, knowledge of the normal anatomy is essential in obtaining diagnostically useful images and aiding interpretation.

The proximal interphalangeal (pastern) joint is the diarthrodial articulation of the proximal and middle phalanges (referred to as P1 and P2 respectively) and is a low motion, high load joint.The middle phalanx is a compact bone, enclosed distally within the hoof capsule and coronary band. Numerous soft tissue structures cross the joint, including the common digital extensor tendon dorsally and the deep digital flexor tendon on the palmar aspect. The superficial digital flexor, along with the straight distal sesamoidean ligament, inserts on the distal palmar aspect of P1 and the proximal palmar aspect of P2. Sagittal support for the joint is provided by medial and lateral collateral ligaments which attach to collateral tubercles proximally and distally. Together, these soft tissue structures prevent over extension of the distal limb, and provide stability.

Although ultrasonography is widely used in equine orthopedics, its use in the distal portion of the digit is still limited. The purpose of this descriptive study was to document the normal ultrasonographic appearance of the palmarodistal aspect of the digital area imaged between the bulbs of the heels. Ultrasonographic images were obtained with a 7.5 MHz microconvex transducer in 10 fresh equine cadaver forelimbs and five sound horses. Sagittal, parasagittal, and transverse images were obtained from the proximal aspect of the middle phalanx to the distal sesamoid bone. Anatomic sections were obtained from five cadaver specimens to correlate the sonographic appearance with the anatomic findings. The remaining cadaver limbs were dissected to confirm normalcy. Ultrasonographic examinations were possible on all digits but distal images were more difficult to obtain in digits with long heels. Bony structures (palmar surface of the middle phalanx and proximal border of the distal sesamoid bone) and soft tissue structures (deep digital flexor tendon, digital tendon sheath, proximal palmar recess of the distal interphalangeal joint, proximal recess of the podotrochlear bursa, collateral sesamoidean ligaments) identified on the anatomic slices were seen on the matched sonographic images. Ultrasonography provides good anatomic details of the palmarodistal aspect of the digit. The images of this study will serve as a reference for clinical studies on ultrasonography of the palmarodistal aspect of the digit.

The distal forelimb of the horse has a complex array of ligaments that play a critical role in determining function of the digit and are often associated with the initiation of foot pathologies. The collateral ligaments of the distal sesamoid bone (CLDS) play an important role in digit stabilization near the end of foot contact and there is also limited evidence to suggest that the CLDS stabilize the proximal interphalangeal joint (PIPJ) during weight bearing. By virtue of their anatomical attachments where the ligaments pass dorsal to the axis of rotation of the PIPJ, it is reasonable to assume that the CLDS prevent flexion of the PIPJ during weight bearing or midstance in a moving horse. To test this functional hypothesis, forelimb specimens from three mixed-breed horses were loaded in compression in a materials testing frame. Limb loading was applied with the CLDS intact and following transection. Average PIPJ angle and metacarpophalangeal joint (MCPJ) angle at maximum load (approximately 3000 N) were calculated from angular changes of proximal and middle phalanges and the third metacarpal, which were compared between intact and transected trials. PIPJ angles were found to be the same (175 degrees) at maximum load for intact and transected trials. The proximal and middle phalanges rotated together remaining aligned, regardless of the CLDS condition. Contrary to expectation, however, the combined proximal and middle phalanges unit rotates less relative to the third metacarpal under load after transection, indicating less digit extension at the metacarpophalangeal (fetlock) joint without the influence of CLDS. Since the mechanical properties of the fetlock joint are unchanged by CLDS transection, observed proximal and middle phalanx motion is dependent on increased rotation of the distal phalanx after transection. The original hypothesis was not supported and the results suggest that at midstance the CLDS function primarily to stabilize the articulation of the middle phalanx about the distal phalanx to limit distal interphalangeal joint extension during weight bearing. Establishing the functional role of the CLDS may help to better understand the biomechanical consequences of ligament injuries and diseases of the pastern.

A pregnant quarterhorse mare became acutely lame as a result of severe swelling of its right hind leg, thought to have been caused by a fracture or a muscle tear. Diagnostic procedures ruled out a traumatic musculoskeletal cause and a physical examination revealed chronic pastern dermatitis ('scratches'/'grease heel'). Histopathological evaluation of biopsy samples from the right hind leg was consistent with a leucocytoclastic vasculitis, and culture yielded Staphylococcus intermedius. The treatment and infectious causes of pastern dermatitis are discussed.

Objective—To determine clinical history, structures involved, treatment, and outcome of lacerations of the heel bulb and proximal phalangeal region (pastern) in horses. Design—Retrospective study. Animals—101 horses. Procedures—Medical records of horses with lacerations of the heel bulb and pastern were reviewed, and follow-up information was obtained. Results—75 horses were Quarter Horses. Most horses were not treated with antimicrobial drugs prior to referral. Mean ± SD time from injury to referral was 24 ± 45 hours (range, 1 to 168 hours). Lacerations were most frequently caused by contact with wire or metal objects. In 17 horses, lacerations involved synovial structures; the distal interphalangeal joint was most commonly affected. One horse was euthanatized after initial examination. Wound treatment consisted of cleansing, lavage, debridement, lavage of affected synovial structures, suturing of fresh wounds, and application of a foot bandage or cast. Fifty-six horses were treated with systemically administered antimicrobial drugs. Follow-up information was collected for 61 horses. Fifty-one horses returned to their intended use and had no further complications; 10 horses had complications associated with the wound, and of those horses, 5 were euthanatized and 1 horse died from an unrelated cause. Horses with lacerations that involved synovial structures had worse outcomes than horses with lacerations that did not involve synovial structures. Conclusions and Clinical Relevance—Horses that sustain heel bulb lacerations can successfully return to their intended use. Involvement of the distal interphalangeal joint is associated with poor prognosis. (J Am Vet Med Assoc 2005;226:418–423)

Ultrasonographic evaluation of the metacarpus (MC), metatarsus (MT), and pastern has been used to diagnose soft tissue injuries of these regions for the past two decades. Advancements in technology continue to improve user friendliness as well as our ability to diagnose tendon and ligament injuries. Relevance of these advances to the equine practitioner will be presented. Techniques to evaluate all major anatomic structures will be discussed, including the superficial and deep digital flexor tendons, inferior check ligament, suspensory ligament, straight and oblique distal sesamoidean ligaments, and collateral and abaxial and axial palmar/plantar ligaments of the pastern joint. Evaluation of associated synovial structures will be presented, including the carpal sheath, tarsal sheath, and digital sheath. An emphasis will be placed on measuring cross-sectional areas as a means to differentiate injured from noninjured structures and how to utilize those measurements to evaluate healing. Common history, physical examination findings, ultrasonographic features, healing, and prognosis for soft tissue injuries of MC, MT, and pastern will be reviewed. Practice tips to improve sonographic technique and image acquisition will also be presented.

The purpose of this study was to evaluate the influence of camped under and upright pastern in front conformation in the forelimb movement of 11 Andalusian Purebreds. Horses were divided into 2 groups: Group 1, camped under and upright pastern horses, comprising 5 animals that when observed from a lateral perspective stand consistently with the entire forelimb behind of the plumb line and have excessive values regarding fetlock and pastern inclination angles; and Group 2, comprising 6 normal forelimb conformation horses. Each animal was recorded at the walk and the trot using a conventional videocamera (frame rate 1/25 sec) from a lateral view. Basic stride parameters (speed, stride length, stride duration, swing phase duration, and stance phase duration), overreach distance, hoof height, retraction-protraction and metacarpophalangeal joint angles (maximum, minimum, angular range of motion), and moments of maximal extension (PMax) and flexion (PMin) were all calculated. Biokinematic studies showed significant changes in the overreach distance at trot and in the metacarpophalangeal joint at walk in horses with the defects. Horses driven in Group 1 displayed a higher hoof trajectory. At walk as well as at trot, the range of movement in the metacarpophalangeal joint was significantly greater in camped under and upright pastern horses.

Conformation is the form (outline) or physical appearance of a horse from the arrangement of muscles, bones, and tissues. In Thoroughbreds long bone and segmental limb lengths are proportional and relationships exist between these measurements and withers height. Carpal conformation progressively changes from “back at the knee” to slightly “over at the knee” between the weanling and 3-year-old year and this is an important consideration when evaluating weanlings and yearlings, as one should avoid selecting individuals that are over-at-the-knee at an early age. Likewise, a foal that is back-at-the-knee will likely improve considerably with age. The angle of the scapula, shoulder joint, and radiometacarpus significantly increases between all ages. Therefore, long bone growth and the increase in upper angles may influence mature height. Horses with longer shoulders had decreased odds and horses with long pasterns had increased odds of forelimb fractures. Scapula and front pastern lengths were both correlated with withers height for 3-year-old horses. In racing Quarter Horses increased length of humerus was associated with osteochondral fractures of the proximal phalanx and synovitis/capsulitis in both carpal joints. Leg length increased the odds of sustaining osteochondral fracture in the carpus, implying that longer legs could predispose to an increased incidence of fracture. Increased length of toe increased the odds of sustaining a carpal chip fragment. As shoulder angle increased, the odds of an osteochondral fracture of the carpus increased. As the pastern became more upright there was decreased chance of sustaining carpal synovitis/capsulitis. As carpal offset ratio increased by 10% the odds of synovitis/capsulitis in left and right forelimbs increased. As the hoof length ratio increased the odds of sustaining carpal osteochondral fracture increased.

Horses with severe and deep lacerations are represented by ten cases in which treatment emphasized the use of bovine collagen preparations to promote controlled second-degree repair. Traumatized areas were tarsal, metatarsal, neck, forearm, metacarpal and pastern. Wound size changes were recorded. Depending on the wound type, the site was treated with antibiotic-steroid ointment, organic acid cream, sterile collagen particles, suspension or dressings protected by hydrogel dressing, non-adherent pads, occlusive skin dressings, roll gauze and elastic tape. In three cases, a fiberglas cast was applied over a hind leg wound and lacerated tendon for stability. When controlled granulation of the deeper wounds reached skin level, the area often was stabilized by only cyanoacrylate spray. As these cases presented a wide range of trauma each with a unique history, healing rates were based on initial measurements. An overall progression of wound reduction occurred at a predictable rate. The exogenous collagen formulations were used to stimulate controlled granulation, ie. to “jump start” the healing process. Collagen particles, suspension or dressings were packed into depressions, placed under suture lines, secured over abraded tissue, and placed under protective bandage or cast. To further evaluate the use of cyanoacrylate tissue spray in wound treatments, an additional ten cases are presented. The variety of wounds were produced experimentally in Center-owned ponies or provided as clinical cases. Wound size changes and healing progress were recorded. Wounds occurred on the neck, abdomen, metacarpal, metatarsal, fetlock and pastern areas. Depending on wound type, the site was treated with cyanoacrylate only; or treated as above until controlled granulation attained skin level. In one case punch grafts of skin were transferred from one foreleg to the opposite with the horse standing. Cyanoacrylate spray provided a water proof barrier protecting the wound from dirt, debris and insects as well as stabilizing full-thickness skin lacerations by bridging normal to traumatized skin allowing uninterrupted granulation and epithelialization. The use of a neck cradle prevented wound disturbance and stall confinement aided stabilization.

Motion of the navicular bone might play a role in the development of navicular disease in horses but is difficult to asses. In the present study, 3-dimensional motion of this bone was determined using roentgen stereophotogrammetric analysis. Tantalum pellets were inserted, in vitro, in the bones of 6 forelimbs of mature Shetland ponies and kinematics were measured during vertical loading up to 2 kN. The motions of the navicular bone and coffin joint were limited to flexion/extension, there were no substantial out-of-plane motions. There was only little flexion between the navicular bone and the coffin bone, which was correlated (r = 0.66) with coffin joint flexion. There was substantial flexion between the navicular bone and the short pastern, which was highly correlated with coffin joint flexion (r = 0.97). We conclude that the navicular bone, generally, follows the coffin bone during coffin joint flexion, although there are small but consistent motions between the navicular bone and the coffin bone. These motions might play a role in the development of navicular disease in horses.