Hindlimb Lameness Research Articles

Disseminated aspergillosis in a German shepherd mixed breed dog with unusual initial localization to the iliac wing.

A female, 1.5 years old, mixed‑breed dog, was presented for left hind limb lameness. Radiographs revealed an irregular periosteal proliferation on the left iliac wing. The clinical condition worsened with generalised enlargement of the lymph nodes, azotaemia, and pyelonephritis. The magnetic resonance imaging of the pelvis and a surgical biopsy diagnosed a mycotic myositis and osteomyelitis of the iliac wing and gluteal muscles. Aspergillus terreus was isolated from culture of urine and lymph nodes aspirates. The antifungal susceptibility test showed moderate sensitivity to Itraconazole. After one month of therapy with itraconazole, the dog presented discospondylitis of L1‑L2 and partial ureteral obstruction due to mycotic bezoar that was resolved with medical treatment and itraconazole dose elevation. After twelve months, itraconazole was suspended; a severe osteomyelitis of the left femur developed, and the dog was euthanised. The necropsy confirmed the presence of mycotic osteomyelitis of the iliac wing and femur, discospondylitis, lymphadenitis and severe granulomatous pyelonephritis. Systemic aspergillosis has rarely been reported in the literature, especially in Italy. The pelvic bone involvement is rare both in dogs and humans. Although itraconazole treatment allowed remission of the clinical signs for one year, it was not able to cure the dog.

Investigation of Thresholds for Asymmetry Indices to Represent the Visual Assessment of Single Limb Lameness by Expert Veterinarians on Horses Trotting in a Straight Line.

Defining whether a gait asymmetry should be considered as lameness is challenging. Gait analysis systems now provide relatively accurate objective data, but their interpretation remains complex. Thresholds for discriminating between horses that are visually assessed as being lame or sound, as well as thresholds for locating the lame limb with precise sensitivity and specificity are essential for accurate interpretation of asymmetry measures. The goal of this study was to establish the thresholds of asymmetry indices having the best sensitivity and specificity to represent the visual single-limb lameness assessment made by expert veterinarians as part of their routine practice. Horses included in this study were evaluated for locomotor disorders at a clinic and equipped with the EQUISYM® system using inertial measurement unit (IMU) sensors. Visual evaluation by expert clinicians allocated horses into five groups: 49 sound, 62 left forelimb lame, 67 right forelimb lame, 23 left hindlimb lame, and 23 right hindlimb lame horses. 1/10 grade lame horses were excluded. Sensors placed on the head (_H), the withers (_W), and the pelvis (_P) provided vertical displacement. Relative difference of minimal (AI-min) and maximal (AI-max) altitudes, and of upward (AI-up) and downward (AI-down) amplitudes between right and left stance phases were calculated. Receiver operating characteristic (ROC) curves discriminating the sound horses from each lame limb group revealed the threshold of asymmetry indice associated with the best sensitivity and specificity. AI-up_W had the best ability to discriminate forelimb lame horses from sound horses with thresholds (left: -7%; right: +10%) whose sensitivity was greater than 84% and specificity greater than 88%. AI-up_P and AI-max_P discriminated hindlimb lame horses from sound horses with thresholds (left: -7%; right: +18% and left: -10%; right: +6%) whose sensitivity was greater than 78%, and specificity greater than 82%. Identified thresholds will enable the interpretation of quantitative data from lameness quantification systems. This study is mainly limited by the number of included horses and deserves further investigation with additional data, and similar studies on circles are warranted.

Adaptations in equine appendicular muscle activity and movement occur during induced fore- and hindlimb lameness: An electromyographic and kinematic evaluation.

The relationship between lameness-related adaptations in equine appendicular motion and muscle activation is poorly understood and has not been studied objectively. The aim of this study was to compare muscle activity of selected fore- and hindlimb muscles, and movement of the joints they act on, between baseline and induced forelimb (iFL) and hindlimb (iHL) lameness. Three-dimensional kinematic data and surface electromyography (sEMG) data from the fore- (triceps brachii, latissimus dorsi) and hindlimbs (superficial gluteal, biceps femoris, semitendinosus) were bilaterally and synchronously collected from clinically non-lame horses (n = 8) trotting over-ground (baseline). Data collections were repeated during iFL and iHL conditions (2-3/5 AAEP), induced on separate days using a modified horseshoe. Motion asymmetry parameters and continuous joint and pro-retraction angles for each limb were calculated from kinematic data. Normalized average rectified value (ARV) and muscle activation onset, offset and activity duration were calculated from sEMG signals. Mixed model analysis and statistical parametric mapping, respectively, compared discrete and continuous variables between conditions (α= 0.05). Asymmetry parameters reflected the degree of iFL and iHL. Increased ARV occurred across muscles following iFL and iHL, except non-lame side forelimb muscles that significantly decreased following iFL. Significant, limb-specific changes in sEMG ARV, and activation timings reflected changes in joint angles and phasic shifts of the limb movement cycle following iFL and iHL. Muscular adaptations during iFL and iHL are detectable using sEMG and primarily involve increased bilateral activity and phasic activation shifts that reflect known compensatory movement patterns for reducing weightbearing on the lame limb. With further research and development, sEMG may provide a valuable diagnostic aid for quantifying the underlying neuromuscular adaptations to equine lameness, which are undetectable through human observation alone.

The Effect of Chiropractic Treatment on Limb Lameness and Concurrent Axial Skeleton Pain and Dysfunction in Horses.

Simple SummaryThe use of chiropractic techniques is common in horses and a strong body of evidence exists for effectively treating back pain and stiffness. Chronic limb lameness can induce complex interactions with the neck, back and pelvis in affected horses, which can be a challenging clinical issue with limited available conservative treatment options. We used a comprehensive array of tests to measure lameness, pain, stiffness, and muscle hypertonicity to evaluate the global effects of chiropractic care in horses with chronic lameness. Four chiropractic treatment sessions were applied over 3 weeks. Improvements in subjective measures of lameness, back muscle pain, and neck or back stiffness were noted. Further studies are needed to better identify the type and severity of lameness that may be amendable to chiropractic treatment.Chiropractic care is a common treatment modality used in equine practice to manage back pain and stiffness but has limited evidence for treating lameness. The objective of this blinded, controlled clinical trial was to evaluate the effect of chiropractic treatment on chronic lameness and concurrent axial skeleton pain and dysfunction. Two groups of horses with multiple limb lameness (polo) or isolated hind limb lameness (Quarter Horses) were enrolled. Outcome measures included subjective and objective measures of lameness, spinal pain and stiffness, epaxial muscle hypertonicity, and mechanical nociceptive thresholds collected on days 0, 14, and 28. Chiropractic treatment was applied on days 0, 7, 14, and 21. No treatment was applied to control horses. Data was analyzed by a mixed model fit separately for each response variable (p < 0.05) and was examined within each group of horses individually. Significant treatment effects were noted in subjective measures of hind limb and whole-body lameness scores and vertebral stiffness. Limited or inconsistent therapeutic effects were noted in objective lameness scores and other measures of axial skeleton pain and dysfunction. The lack of pathoanatomical diagnoses, multilimb lameness, and lack of validated outcome measures likely had negative impacts on the results.

Artificial Intelligence for Lameness Detection in Horses-A Preliminary Study.

Simple SummaryIn the expanding field of artificial intelligence, deep learning and smart-device-technology, a diagnostic software tool was developed, which can help distinguish between lame and sound horses and locate the affected limb. As lameness influences the welfare of horses and is often difficult to detect, this tool can help owners and veterinarians in the process of evaluation. The technology is based on pose estimation, which is already used in human and veterinary science to study movement of limbs or bodies without the need to fix any devices onto the object of interest. In this study, 22 horses with unilateral fore- or hindlimb lameness and a control group of eight sound horses were analysed with the program. Based on the results of the program, it was possible to differentiate between horses with fore- and hindlimb lameness and sound horses. Difficult light settings, such as direct sunlight or darkness, or very even-coloured coats, complicate the precise placement of reference points. The analysis and detection with software-generated movement trajectories using pose estimation is very promising but requires further development.Lameness in horses is a long-known issue influencing the welfare, as well as the use, of a horse. Nevertheless, the detection and classification of lameness mainly occurs on a subjective basis by the owner and the veterinarian. The aim of this study was the development of a lameness detection system based on pose estimation, which permits non-invasive and easily applicable gait analysis. The use of 58 reference points on easily detectable anatomical landmarks offers various possibilities for gait evaluation using a simple setup. For this study, three groups of horses were used: one training group, one analysis group of fore and hindlimb lame horses and a control group of sound horses. The first group was used to train the network; afterwards, horses with and without lameness were evaluated. The results show that forelimb lameness can be detected by visualising the trajectories of the reference points on the head and both forelimbs. In hindlimb lameness, the stifle showed promising results as a reference point, whereas the tuber coxae were deemed unsuitable as a reference point. The study presents a feasible application of pose estimation for lameness detection, but further development using a larger dataset is essential.

Evaluation of feedback methods for improved detection of hindlimb lameness in horses among riding instructors and trainers.

Lameness, a wellknown issue in sport horses, impedes performance and impairs welfare. Early detection of lameness is essential for horses to receive needed treatment, but detection of hindlimb lameness is challenging. Riding instructors and trainers observe horses in motion in their daily work and could contribute to more efficient lameness detection. In this cross-sectional and prospective study, we evaluated the ability of riding instructors and trainers to assess hindlimb lameness. We also evaluated different feedback methods for improved lameness detection. For the cross-sectional part, n = 64 riding instructors and trainers of varying level and n = 23 high-level trainers were shown 13 videos of trotting horses, lameness degree: 0–3.5 (test 1) and tasked with classifying the horses as sound, left hindlimb lame, or right hindlimb lame. For the prospective part, the riding instructors and trainers of varying levels were randomly allocated to three different groups (a, b, c) and given 14 days of feedback-based, computer-aided training in identifying hindlimb lameness, where they assessed 13 videos (of which three were repeated from test 1) of horses trotting in a straight line. Participants in groups a-c received different feedback after each video (group a: correct answer and re-viewing of video at full and 65% speed; group b: correct answer, re-viewing of video at full and 65% speed, narrator providing explanations; group c: correct answer and re-viewing of video at full speed). After computer-aided training, the participants were again subjected to the video test (test 2). Participants also provided background information regarding level of training etcetera. Effects of participants' background on results were analyzed using analysis of variance, and effects of the different feedback methods were analyzed using generalized estimation equations. On test 1, 44% (group a), 48% (b), 46% (c), and 47% (high-level trainers) of horses were correctly classified. Group a participants significantly improved their test score, both with (p < 0.0001) and without (p = 0.0086) inclusion of repeated videos. For group c, significant improvement was only seen with inclusion of repeated videos (p = 0.041). For group b, no significant improvement was seen (p = 0.51). Although test 2 scores were low, computer-aided training may be useful for improving hindlimb lameness detection.

Changes in Head, Withers, and Pelvis Movement Asymmetry in Lame Horses as a Function of Diagnostic Anesthesia Outcome, Surface and Direction

Evaluation of diagnostic anesthesia during equine lameness examination requires comparison of complex movement patterns and can be influenced by expectation bias. There is limited research about how changes in movement asymmetries after successful analgesia are affected by different exercise conditions. Movement asymmetry of head, withers and pelvis was quantified in N = 31 horses undergoing forelimb or hindlimb diagnostic anesthesia. Evaluation on a straight line and a circle was performed with subjective diagnostic anesthesia outcome and quantitative changes recorded. Mixed linear models (P < .05) analyzed the differences in movement asymmetry before/after diagnostic anesthesia - random factor: horse, fixed factors: surface (soft, hard), direction (straight, inside, outside, inside-outside average), diagnostic anesthesia outcome (negative, partially positive, positive) and two-way interactions. Forelimb diagnostic anesthesia influenced primary movement asymmetry (all head and withers parameters) and compensatory movement asymmetry (two pelvic parameters) either individually (P≤.009) or in interaction with surface (P≤.03). Hindlimb diagnostic anesthesia influenced primary movement asymmetry (all pelvic parameters) and compensatory movement asymmetry (two head and two withers parameters) either individually (P≤.04) or in interaction with surface (P≤.01;) or direction (P≤.006). Direction was also significant individually for two pelvic parameters (P≤.04). Changes in primary movement asymmetries after partially positive or positive outcomes indicated improvement in the blocked limb. Compensatory changes were mostly in agreement with the ‘law of sides’. The changes were more pronounced on the hard surface for hindlimb lameness and on the soft surface for forelimb lameness. Withers asymmetry showed distinct patterns for forelimb and hindlimb lameness potentially aiding clinical decision-making.

Comparison of Hindlimb Conformation in Cats with and without Medial Patellar Luxation.

Medial patellar luxation (MPL) is the most common developmental cause of hindlimb lameness in cats. The association between femoral and tibial conformation and MPL measured on computed tomography (CT) has not been reported in cats. The aims were to report femoral and tibial conformation in cats with and without MPL and to report normal femoral and tibial angles. Angle of inclination of femoral neck (AI), anatomical lateral distal femoral angle (aLDFA), femoral trochanteric angle (FCT), angle of anteversion of femoral neck (AA), distal and proximal anteversion angle (DAA/PAA), overall tibial valgus (TV), tibial torsion (TT), tibial tuberosity displacement (TTD) and trochlear depth:patellar thickness ratio (T:P) were measured by three observers on CT of cats with and without MPL. Comparisons were made between groups. Inter-observer intraclass correlation coefficient (ICC) was calculated. Sixteen cats were recruited: eight control and eight with MPL. The aLDFA, PAA, TT, TTD and T:P were significantly less in cats with high-grade MPL. The AI, FCT, AA, DAA and TV were not significantly different. A high correlation was shown with inter-observer ICC in 33.33% and good correlation in 26.67% when comparing measurements between observers. This study suggests that cats with high-grade MPL have decreased TT, TTD and T:P and may require tibial tuberosity transposition and femoral trochleoplasty. The PAA, TT and aLDFA were decreased, although clinical significance may vary and these cats may not require correctional osteotomies. Results should be interpreted with caution as high/good levels of inter-observer ICC occurred in less than two-thirds of cases between observers.

FIZJOTERAPIA JAKO WSPOMAGANIE POOPERACYJNEGO LECZENIA ZERWANIA WIE ̨ZADŁA ̇ KRZYZOWEGO PRZEDNIEGO U PSÓW: OPIS PRZYPADKU

Rupture of the cranial cruciate ligament (CCL) in the stifle is one of the most common causes of hind-limb lameness in middle-aged and old dogs. The treatment of choice involves surgical extra- or intra-capsular stabilization of the knee joint, or the increasingly preferred tibial osteotomy techniques. Postoperative rehabilitation of the affected limb is an equally important part of the treatment. The paper describes three cases of rupture of the cruciate ligament in dogs and the methods of physiotherapeutic treatment applied to them. The techniques of passive and active exercises were used along with massage and physical therapy, such as magnetotherapy, ultrasound, electrotherapy, and laser therapy. The development of the correct physiotherapeutic treatment plan, the selection of techniques, and the duration of therapy is crucial for its effectiveness. It has been shown that rehabilitation has a positive effect on the tissue healing process. It also shortens the time needed to restore full mobility of the affected limb, both during the non-complicated healing process and in the event of problematic cases.

Extracapsular stabilization for the treatment of cranial cruciate ligament rupture in a ferret

AbstractA 1‐year‐old, male, neutered ferret was presented with a history of 2 weeks of left hindlimb lameness. Orthopaedic exam and radiographs were consistent with a complete cranial cruciate ligament rupture. An extracapsular stabilization was performed. Progressive lameness improvement was observed during the first 15 days after surgery and a complete resolution was achieved 3 weeks after surgery. Twenty‐one months after surgery, no lameness or recurrence was reported and moderate osteoarthritis developed at radiographic follow‐up. This is the first case of surgical management of cranial cruciate ligament in a ferret with long‐term follow‐up. Even if this disease is rarely reported in this species, cranial cruciate ligament should be included in differential diagnosis of ferret's hindlimb lameness. Surgical management is feasible and could be considered as an alternative to conservative management.

An objective study into the effects of an incline on naturally occurring lameness in horses.

The clinical examination of lame horses in real world settings often requires the use of sloped surfaces. This pilot study aimed to evaluate the effects of uphill and downhill locomotion on asymmetry in horses with naturally occurring lameness affecting forelimbs and hindlimbs. Ten horses (8-19 years) with forelimb lameness and eight horses (7-16years) with hindlimb lameness were fitted with inertial sensors at the poll, withers, sacrum and both tuber coxae. Data were collected whilst the horses were trotted in hand on a level surface (<0.7%), as well as up and down a minor slope of 2.4%. Data were collected for a minimum of 25 strides at each incline type. Effect of incline was compared using a repeated measures ANOVA and, where significant, a subsequent Bonferroni's multiple comparisons. Of the horses with hindlimb lameness, there were reductions in asymmetry seen during downhill locomotion when compared with trotting on the flat (flat: 6.6 ± 4.4mm to downhill: 1.9 ± 2.9mm; p = 0.015) and when compared with uphill locomotion (8.4 ± 4.3mm; p = 0.007). Horses with forelimb lameness showed no significant difference in asymmetry. However, there were considerable changes in poll asymmetry (>20mm) among conditions in individual horses. Two horses with hindlimb lameness and two horses with forelimb lameness switched asymmetry between left and right by changing incline. These results confirm that incline can be an influential factor in the assessment of lame horses. Further work is justified to elucidate the types of pathology associated with the most relevant changes in asymmetry which would allow the use of an incline to prioritise a list of differential diagnoses.

Traumatic synovial herniation of the medial femorotibial joint as an aetiology of hindlimb lameness in a horse

SummaryA 3‐year‐old Quarter Horse filly presented with an acute history of right hindlimb lameness. Examination of the right hind found moderate effusion in the medial femorotibial joint and a consistent grade 4/5 right hindlimb lameness. Ultrasonographic evaluation of the medial femorotibial joint revealed a disruption of the synovial membrane in the medial recess of the joint capsule. Arthroscopy of the medial femorotibial joint identified a tear in the joint capsule at the attachment to the medial collateral ligament. Treatment with autologous conditioned serum, rest and firocoxib resulted in improvement in overall lameness. Follow‐up examination revealed an improved lameness score; however, a synovial hernia was identified on sonographic evaluation of the joint.

CT findings in 21 foals with undiagnosed hindlimb lameness

CT findings in 21 foals with undiagnosed hindlimb lameness

Development of an Artificial Neural Network for the Detection of Supporting Hindlimb Lameness: A Pilot Study in Working Dogs.

Simple SummaryMany of the rules considered valid in the ambit of lameness detection in domestic animals are mainly subjective or acquired after extended clinical experience. Thus, it is necessary to develop tools and/or technologies to provide objective data to discern between sound and lame animals. The main objective of this study is to develop an artificial neural network by analyzing data obtained from an inertial sensor in order to discriminate between sound and lame dogs. After different system adjustments, the neural network has been able to correctly determine whether dogs were lame in about 86% of cases. Furthermore, a web app was developed to manage and follow the different cases. An artificial neural network was designed and developed to analyze spatial data from inertial sensors and to detect motion alterations in dogs with unilateral lameness. Displayed within a user-friendly, intuitive web app, the system could be a useful tool for lameness detection for veterinary clinicians.Subjective lameness assessment has been a controversial subject given the lack of agreement between observers; this has prompted the development of kinetic and kinematic devices in order to obtain an objective evaluation of locomotor system in dogs. After proper training, neural networks are potentially capable of making a non-human diagnosis of canine lameness. The purpose of this study was to investigate whether artificial neural networks could be used to determine canine hindlimb lameness by computational means only. The outcome of this study could potentially assess the efficacy of certain treatments against diseases that cause lameness. With this aim, input data were obtained from an inertial sensor positioned on the rump. Data from dogs with unilateral hindlimb lameness and sound dogs were used to obtain differences between both groups at walk. The artificial neural network, after necessary adjustments, was integrated into a web management tool, and the preliminary results discriminating between lame and sound dogs are promising. The analysis of spatial data with artificial neural networks was summarized and developed into a web app that has proven to be a useful tool to discriminate between sound and lame dogs. Additionally, this environment allows veterinary clinicians to adequately follow the treatment of lame canine patients.

Effect of Needle and Extracorporeal Shockwave Stimulation of Acupuncture Points on Equine Chronic Multilimb Lameness Using a Single-Formula Approach

Abstract Objective The aim of this study was to compare effects with conventional (needle and electroacupuncture, NAP) and shockwave stimulation of acupuncture points (SAP) on chronic multilimb lameness in horses. Study Design Randomized crossover block design; ten mature Standardbred mares with multilimb lameness (&lt; 4/10) underwent 3-weekly point stimulations (NAP/SAP) selected on the basis of their uniform applicability. Groups were reversed following a washout period (9 weeks). Lameness at the trot was video recorded and quantified objectively using an inertial sensor-based system during a 4-week pre- and post-treatment period. Blinded expert review of recordings resulted in subjective qualitative (better, same, or worse) and quantitative outcome measures (0–10 lameness grade). Mixed effect repeated measures analyses were performed on objective quantitative gait parameters specific to fore (Vector sum [VSHead]) and hindlimb lameness (average differences in minimum [DIFFMINPelvis] and maximum pelvic height [DIFFMAXPelvis]) Qualitative data were assessed in non-parametric tests. Results SAP had no effect on forelimb but improved hindlimb lameness (DIFFMINPelvis; p &lt; 0.001). NAP was associated with deterioration of forelimb lameness (VSHead, p &lt; 0.001) and had no effect on hindlimb lameness. VSHead data differed between modalities when accounting for the time of observation (interaction effect; p = 0.002). For other quantitative gait parameters, a difference between modalities was not observed. SAP was associated with greater animal comfort post-treatment compared with pre-treatment assessments (p = 0.036). Typically, improvement occurred by one and deterioration by two lameness grades. Conclusion SAP and NAP were not associated with the same treatment outcome. SAP slightly improved but did not alleviate all lameness. Given the non-invasive nature of SAP, this method may have potential in the management of chronic multilimb lameness.

Influence of Chronic Lameness on Thoracolumbar Musculus Multifidus Structure in the Horse

The clinical relationship between equine limb lameness and secondary back dysfunction is largely unknown. Proper function of the spine is critical to maintain the integrity of the kinetic chain and attenuate forces from the appendicular skeleton. The musculus multifidus (m. multifidus) is the primary muscle providing spinal intersegmental stabilization and a functional relationship between m. multifidus hypertrophy and equine postural stability has been established. The relationship between equine thoracolumbar m. multifidus cross-sectional area (CSA) and limb lameness is unknown. The objective was to evaluate ultrasonographic changes in thoracolumbar m. multifidus CSA in horses with chronic single limb lameness, compared with sound horses. We hypothesized that the CSA of m. multifidus, ipsilateral to the lame limb would be smaller than the contralateral side, and within the sound group there would be no difference between sides. Thirty-six horses were enrolled, with twelve horses per group: sound, forelimb lame, and hindlimb lame. M. multifidus CSA was measured ultrasonographically at multiple spinal levels and compared between groups, spinal levels, and sides. M. multifidus CSA at the spinal level T18 was significantly larger than at all other measured levels, regardless of group (P ≤ .05). CSA at all levels was significantly larger in sound horses than the forelimb lame group, regardless of side (P = .002). This is the first study to evaluate the impact of chronic lameness on the axial skeleton and showed a decrease in m. multifidus CSA with forelimb lameness. These results support that axial skeletal adaptation occurs in response to naturally occurring chronic lameness.

Spontaneous bilateral superficial digital flexor tendon rupture in a horse with guttural pouch empyema and suspected purpura hemorrhagica

SummaryCase historyAn 11‐year‐old Quarter Horse gelding was evaluated for urticaria, generalised discomfort, distal limb oedema, spontaneous dropped fetlocks, and progressive hindlimb lameness. Prior infection status with Streptococcus equi subspecies equi was unknown.Clinical findingsThe horse had bilateral hindlimb oedema, generalised wheals, progressive hindlimb lameness, and dropped fetlocks of the right and left hindlimbs. The horse was intermittently pyrexic and was ultimately subjected to euthanasia due to deteriorating clinical status.DiagnosisSuspected purpura hemorrhagica associated with leukocytoclastic vasculitis of the superficial digital flexor tendons and spontaneous tendon rupture.Treatment and outcomeThe horse was treated with a combination of antibiotic therapy (enrofloxacin and penicillin), nonsteroidal anti‐inflammatory drugs (phenylbutazone) and corticosteroids (dexamethasone), with no improvement in clinical status. The horse was subjected to euthanasia due to poor prognosis and unfavourable response to therapy. Post‐mortem examination revealed unilateral guttural pouch empyema, multifocal cutaneous infarction and bilateral rupture of the superficial digital flexor tendons. Streptococcus equi subspecies equi was isolated in pure culture from the guttural pouch. Microscopically, leukocytoclastic vasculitis typical of purpura hemorrhagica was documented in the skin. Unexpectedly, similar vasculitis was also observed in the superficial digital flexor tendons.Clinical relevanceThis report documents the first equine case of suspected purpura hemorrhagica associated with leukocytoclastic vasculitis of the superficial digital flexor tendons and spontaneous tendon rupture. Spontaneous tendon rupture should be considered a potential sequela to infection with Streptococcus equi subspecies equi in horses due to immune‐mediated vasculitis.

Computed tomographic diagnosis of a fracture of the floor of the pelvis in a Thoroughbred foal

SummaryThis case report describes the clinical and diagnostic imaging findings, treatment and outcomes of a 15‐day‐old Thoroughbred foal referred for the evaluation of severe left hindlimb lameness of 8 days' duration. Radiographic examination of the left hindlimb and transcutaneous ultrasonographic examination of the pelvis were unremarkable. A computed tomographic (CT) examination was performed to investigate the proximal aspect of the limb and the pelvis; CT scans of the thorax were also acquired. In this case, CT images allowed detection of a closed, slightly displaced, oblique wedge‐like fracture of the left caudal ramus of the pubis and medial ramus of the ischium, allowing an accurate diagnosis to guide appropriate treatment and prognostication. The foal was treated with anti‐inflammatory drugs and box‐rest. A follow‐up by telephone interview with the trainer 3 years later revealed that the horse is in full athletic activity without any residual gait alteration related to the pelvic fracture.

A description of veterinary eliminations within British National Endurance rides in the competitive season of 2019

Veterinary eliminations within the equestrian sport of endurance have predominantly been evaluated based on data from international competitions. However, in order to take part in international competition, each horse and rider must qualify by completing rides under their national federation. The aim of this study was to analyse the competitive data and veterinary eliminations, specifically lameness, from competitions run by the British governing body of endurance: Endurance GB, during the 2019 competitive season. Competitive results for 765 ride starts from seven different ride venues were evaluated; 81.6% (n=624) horses successfully completed the rides, with the remaining 18.4% (n=141) failing to complete the ride. The majority of horses that were unsuccessful were eliminated for lameness at veterinary inspections (n=83; 58.9%). Horses competing in single loop rides (up to 55 km rides) had a success rate of 88.6% (n=624), in contrast, horses competing in rides of three loops or more (&gt;80 km rides) reported a decreased success rate of 61.8% (n=81). Hindlimb lameness was identified more frequently (n=50; 60.2%) compared with forelimb lameness (n=33; 39.8%). Further consideration should be given to the differences between single loop rides, where a higher percentage are presented to the veterinary panel as lame prior to the start, and multi loop rides, where a higher percentage of horses are eliminated lame during the ride and potential risk factors for the increased prevalence of hindlimb lameness observed.

Molecular characteristics and pathogenicity of an equid alphaherpesvirus 1 strain isolated in China.

Equid alphaherpesvirus 1 (EHV-1) is prevalent in China, and causes notable economic damage to the equine industry. However, there is no information regarding the molecular characteristics and pathogenicity of the Chinese strains. Therefore, an EHV-1 strain, named YM2019, was isolated from the lung tissue of an aborted horse fetus in Xinjiang, China, and its genome and pathogenicity were analyzed. The full genome of the isolate was 150,267 base pairs in length, with 56.7% G + C content. Genetic and phylogenetic analysis showed that strain YM2019 (GenBank: MT063054) belonged to the ORF30 N752 genotype but displayed a high level of similarity with strain Ab4 (ORF30 D752, GenBank: AY665713) isolated in Britain. Fourteen unique amino acid mutations were found when comparing strain YM2019 with the reference strains Ab4 and V592 (ORF30 N752, GenBank: AY464052). Syrian hamsters infected with strain YM2019 exhibited severe respiratory and neurological clinical signs and died. Infection with strain YM2019 in Yili horses caused rhinopneumonitis, viremia, and neurological clinical signs such as hind limb lameness, prostration, and reduced movement. Here, we describe the features of an EHV-1 strain discovered in China, together with the complete genome sequence, and reveal that a nonneurovirulent strain (ORF30 N752) can also cause neurological signs in horses. The data will be useful in providing some reference for further research into the relationship between viral genotypes and pathogenicity.