Target Trial Emulation: Does surgical versus non-surgical management of cranial cruciate ligament rupture in dogs cause different outcomes?

Target trial emulation applies design principles from randomised controlled trials to the analysis of observational data for causal inference and is increasingly used within human epidemiology. Using anonymised veterinary clinical data from the VetCompass Programme, this study applied the target trial emulation framework to determine whether surgical (compared to non-surgical) management for cranial cruciate ligament (CCL) rupture in dogs causes improved short- and long-term lameness and analgesia outcomes. The emulated target trial included dogs diagnosed with CCL rupture between January 1, 2019 and December 31, 2019 within the VetCompass database. Inclusion in the emulated trial required dogs aged ≥ 1.5 and < 12 years, first diagnosed with unilateral CCL rupture during 2019 and with no prior history of contralateral ligament rupture or stifle surgery. Dogs were retrospectively observed to have surgical or non-surgical management. Informed from a directed acyclic graph derived from expert opinion, data on the following variables were collected: age, breed, bodyweight, neuter status, insurance status, non-orthopaedic comorbidities, orthopaedic comorbidities and veterinary group. Inverse probability of treatment weighting (IPTW) was used to adjust for confounding, with weights calculated based on a binary logistic regression exposure model. Censored dogs were accounted for in the IPTW analysis using inverse probability of censoring weighting (IPCW). The IPCWs were combined with IPTWs and used to weight each dog's contribution to binary logistic regression outcome models. Standardized mean differences (SMD) examined the balance of covariate distribution between treatment groups. The emulated trial included 615 surgical CCL rupture cases and 200 non-surgical cases. The risk difference for short-term lameness in surgically managed cases (compared with non-surgically managed cases) was -25.7% (95% confidence interval (CI) -36.7% to -15.9%) and the risk difference for long-term lameness -31.7% (95% CI -37.9% to -18.1%). The study demonstrated the application of the target trial framework to veterinary observational data. The findings show that surgical management causes a reduction in short- and long-term lameness compared with non-surgical management in dogs.

A scoring system for grading corkscrew claws in dairy cattle.

Corkscrew claw (CC) in dairy cattle is increasingly reported in dairy herds. CC is a progressive deformity of the claw capsule with uncertain aetiology and pathogenesis. Genetics and specific environmental factors are suspected of contributing to the development of this irreversible condition. CC has been found in lame cows; however, the cause and effect has not been established. To perform analysis of risk factors, treatment and pathogenesis, a definition of severity scores is called for. The aim of this study was to measure and analyse CC characteristics from photos of cows' feet to describe and evaluate a scoring system for CC. Width of the visible part of the axial wall, degree of contact between the toe and the floor and angle of the distal part of the abaxial wall as a proxy for the deviation of the abaxial wall was measured from 393 pictures of CC. Based on the measurements on the claws, the parameter "width of the axial wall" was chosen to define the scores. The parameter was divided into three intervals to define either mild CC 0.3-2.0 cm, moderate CC 2.1-3.5 cm or severe CC>3.5 cm and correlation between the parameters; level of contact between the toe and the floor and the angle of the distal abaxial wall was evaluated. There was a significant positive linear correlation between width of the axial wall and angle of the distal part of the abaxial wall (r=0.91), the wider the axial wall, the more the abaxial wall deviated in the distal part. As the width of the axial wall increased the toe increasingly lost contact with the floor, this association was significant for mild CC and moderate CC but not for severe CC. The Interobserver agreement of the CC Scoring system was tested by 30 claw trimmers each scoring 32 cadaver feet and by 2 trained observers on 28 photos of feet using Cohen´s weighted kappa and showed substantial to almost perfect agreement between untrained and trained observers, respectively.

Deoxynivalenol and fumonisin predispose broilers to bacterial chondronecrosis with osteomyelitis lameness.

Bacterial chondronecrosis with osteomyelitis (BCO) lameness is the most critical animal health and welfare issue facing the broiler industry worldwide. It is estimated that 1 to 2% of bird condemnation at marketing age is caused by BCO lameness, resulting in tens of millions of dollars in annual losses. Fast-growing broilers are prone to mechanical stress that triggers bacterial translocation across epithelial barriers into the bloodstream, followed by bacterial colonization in the growth plate of long bones, and eventually, bone necrosis and lameness. Mycotoxins (MTX) are secondary metabolites produced naturally by microfungi, of which deoxynivalenol (DON), fumonisin (FUM), and zearalenone are the most prevalent in corn and soybean-meal-based diets. The presence of these mycotoxins in feed has been proven to reduce the barrier strength of the intestinal tracts and trigger immunosuppressive effects. In this study, we investigated the effects of the DON and FUM-contaminated feeds on the incidence of BCO lameness in broilers reared in both wire- and litter-floors. 720 one-day-old broiler chicks were assigned to the 2 × 2 factorial design: 2 MTX diets containing DON and FUM on wire flooring (MTX-W) and litter flooring (MTX-L), and 2 diets without MTX contamination on control wire flooring (CW) and control litter flooring (CL). Throughout the trial, the cumulative incidence of lameness per treatment was assessed by necropsying the lame birds. Birds in the MTX-W group had a higher incidence of lameness compared to those in CW (73.3% vs. 62.0%) (P < 0.05), and birds in the MTX-L group had a higher incidence of lameness compared to birds in CL (54.0% vs. 34.0%) (P < 0.05). MTX elicited net increases in BCO to a greater degree on litter (+20%) than on wire flooring (+12%). The increased incidence of BCO lameness in the MTX-W coincided with increased intestinal permeability supporting a correlation between intestinal barrier integrity and BCO lameness. To conclude, DON and FUM are predisposing factors for increasing BCO. However, no significant interaction exists between the diet and floor types in inducing lameness in broilers.

Body conformation traits in early-lactation associated with clinical mastitis and lameness in lactating Chinese holstein cows.

BACKGROUND: Comprehending the correlation between body conformation traits of cows at the early stages of lactation and prevalent lactation diseases might facilitate the execution of selection and feeding strategies that prioritize cow health. This study aimed to evaluate the impact of body conformation traits on the incidence of clinical mastitis and lameness in Chinese Holstein cows. From a pasture herd of 1472 early lactating Chinese Holstein cows, we evaluated 20 body conformation traits. During lactation, this pasture herd was visited weekly to gather clinical mastitis and lameness data. A nine-point scale was used to determine the conformation traits of cows to clarify their linear characters, including frame capacity, rump (RU), feet and leg (FL), mammary system (MS), and dairy character. A longitudinal binary disease (0 = healthy; 1 = diseased) data structure was created by allocating disease records to adjacent official test dates. The impact of body conformation traits on the risk of developing diseases (clinical mastitis and lameness) was analyzed using the logistic regression models. RESULTS: Compared to cows with low total scores (75-79 points), those with high total scores (80-85 points) of body conformation traits had a significantly lower risk of mastitis (P < 0.001). The disease status (0 or 1: binary variable) of clinical mastitis in lactating cows was significantly impacted negatively by age (P < 0.05). The fore udder attachment (FUA), angularity, rear attachment height (RAH), and rear teat placement (RTP) were all significantly associated with clinical mastitis during lactation (P < 0.05). The rear leg-rear view (RLRV) was significantly correlated with correlated considerably (P < 0.05) with lameness during lactation. An ideal score of four points on the lameness risk dimension of the RLRV may indicate a low risk of lameness. Since the risk of mastitis decreased as this trait score increased, the RTP may be an ideal marker for mastitis risk. CONCLUSIONS: According to the study, clinical mastitis and lameness risks in cows can be estimated using their body conformation traits. Cows with more centrally located rear teats have a lower risk of mastitis. These results may help dairy farmers identify cows at high risk of disease early in lactation and aid in breeding for disease resistance in cows.

Intra-articular Fibrolipoma of the Stifle in a Dog.

A 12 yr old male castrated miniature Australian shepherd dog presented for surgical consultation of historical bilateral medial patellar luxations with a 3 mo history of an acute onset of a left pelvic limb lameness. Physical examination confirmed medial patellar luxations and a mass effect of the left stifle medially. Radiographs showed medial distension of the joint capsule by a soft tissue opacity. Fine-needle aspirate of the left stifle revealed a mesenchymal cell population. Left medial parapatellar stifle arthrotomy found a fatty mass, which was excised at its base. A benign fibrolipoma was diagnosed on histopathology, and the excision was expected to be curative. The owners reported immediate improvement of perceived comfort postoperatively. At 2 and 24 wk, the dog returned to a normal level of function. Lipomas of the stifle, although rare, should be considered as a differential for intra-articular masses causing lameness.

Welfare evaluation of dairy cows reared in the East of Algeria.

The aim of the study was to evaluate the welfare status of dairy cows raised in local conditions through health criteria. Important health problems have been identified as well as their effect on the milk yield. One hundred seven farms in eastern Algeria were visited. Data on health, productivity, and management practices were collected. Clinical examination of 1210 dairy cows was conducted to assess health scores. The relationship between herd health and milk yield was investigated using multiple linear regression models. The average milk yield per cow was 16.1 kg/day, and the average prevalence of thin cows (body condition score ≤ 2) was 35.1%. The cow dirtiness was a sign of poor facility hygiene, with 24.3% of cows had dirty udders, 44.5% had dirty flanks/upper legs, and 59.6% had dirty hind legs. The mean prevalence of clinical lameness (locomotion score ≥ 3) and severe lameness (locomotion score ≥ 4) were 24.7% and 8.7%, respectively. The prevalence of hocks, knees, and neck injuries (score > 1) with wound and/or swelling ranged from 0 to 46.2%, 0 to 71.4%, and 0 to 14.3%, respectively. The clinical examination showed a percentage of cows with mastitis of 15.4%, diarrhea of 6.9%, cough of 3.2%, nasal discharge of 7.5%, and ocular discharge of 1.8%. Thus, the milk yield had associated with severe lameness, mastitis, thinness, and dystocia. In conclusion, the welfare indicators in this study reflect the serious health problems in dairy farming which influence the expression of the cow genetic potential.

Radiation from the equine perineal region is low compared with the elbow and head 24 hours after bone scintigraphic examination.

The timing of follow-up radiography and ultrasound in horses that undergo skeletal scintigraphy for lameness investigation varies internationally and between equine hospitals. The prospective, one-group, pretest, posttest study aimed to estimate radiation levels from horses three and 24 h after injection of hydroxydiphosphonate labeled with metastable technetium (99mTc-HDP) and investigate which anatomical locations of the horse had higher radiation levels. Included were 46 horses referred for lameness investigation between June and December 2021. Radiation levels from the horse surface were measured using an electronic device from six anatomical locations (head, elbow, dorsum, ventrum, stifle, and perineum) at two time points and adjusted to three and 24 h after injection of 99mTc-HDP using the radioactive decay law. The radiation measured was significantly different in the various locations of the horses for both time points. At 3 h after injection of 99mTc-HDP, the ventrum had the highest radiation dose. At 24 h, the radiation emitted from the perineal region was significantly lower (P < .0001) than from the elbow and head, which had the highest values. There was a negative correlation between age and the radiation detected at 24 h postinjection (P = .02). Radiation from the perineal region was low compared with other regions of the horse 24 h postscintigraphy. Additional care should be taken around the ventrum area during the scintigraphy examination and around the elbow and head at 24 h postscintigraphy to minimize radiation to personnel.

A prospective cohort study examining the association of claw anatomy and sole temperature with the development of claw horn disruption lesions in dairy cattle.

Foot characteristics have been linked to the development of sole lesions (sole hemorrhage and sole ulcers) and white line lesions, also known as claw horn disruption lesions (CHDL). The objective of this study was to examine the association of claw anatomy and sole temperature with the development of CHDL. A cohort of 2,352 cows was prospectively enrolled from 4 UK farms and assessed at 3 time points: before calving (T1-precalving), immediately after calving (T2-calving), and in early lactation. At each time point body condition score was recorded, a thermography image of each foot was taken for sole temperature measurement, the presence of CHDL was assessed by veterinary surgeons, and an ultrasound image was taken to retrospectively measure the digital cushion and sole horn thickness. Additionally, at the postcalving time point, foot angle and heel depth were recorded. Four multivariable logistic regression models were fit to separately examine the relationship of precalving and postcalving explanatory variables with the development of either white line lesions or sole lesions. Explanatory variables tested included digital cushion thickness, sole horn thickness, sole temperature, foot angle, and heel depth. Farm, parity, body condition score, and presence of lesion at the time of measurement were also included in the models. A thicker digital cushion shortly after calving was associated with decreased odds of cows developing sole lesions during early lactation (odds ratio [OR]: 0.74, 95% confidence interval [CI]: 0.65-0.84). No association was found between digital cushion thickness and development of white line lesions. Sole temperature after calving was associated with increased odds of the development of sole lesions (OR: 1.03, 95% CI: 1.02-1.05), and sole temperature before and after calving was associated with the development of white line lesions (T1-precalving OR: 1.04, 95% CI: 1.01-1.07; T2-calving OR: 0.96, 95% CI: 0.93-0.99). Neither foot angle nor heel depth was associated with the development of either lesion type. However, an increased sole horn thickness after calving reduced the odds of cows developing sole lesions during early lactation (OR: 0.88, 95% CI: 0.83-0.93), highlighting the importance of maintaining adequate sole horn when foot trimming. Before calving, animals with a lesion at the time of measurement and a thicker sole were more likely to develop a sole lesion (OR: 1.23, 95% CI: 1.09-1.40), compared with those without a sole lesion. The results presented here suggest that white line and sole lesions may have differing etiopathogenesis. Results also confirm the association between the thickness of the digital cushion and the development of sole lesions, highlight the association between sole horn thickness and sole lesions, and challenge the potential importance of foot angle and heel depth in the development of CHDL.

Bovine Lameness from the Ground up.

Lameness in bulls is a common problem seen by many veterinarians, and the cause can be difficult to determine. Understanding cattle lameness requires experience and complete knowledge of their structural anatomy and handling. This article reviews the common body regions that cause lameness in bulls and discusses their treatment. It also details hoof trimming as a way to manage lameness.

Trochlear Ridge Prostheses for Reshaping Femoral Trochlear Ridges in Dogs with Patellar Luxation.

OBJECTIVES: To describe the implant characteristics and surgical application of a custom-made trochlear ridge prosthesis (TRP) and to report clinical outcomes in dogs affected by patellar luxation treated with TRP. STUDY DESIGN: Dogs affected by patellar luxation underwent computed tomography. A specific canine bone anatomical replica, a cutting guide, and a TRP were designed and provided for surgery. Surgical records, clinical and radiographic reassessments, complications, pre- and postoperative lameness, type and degree of patellar luxation, and TRP and patellar position after surgery were reviewed. Clinical outcomes were defined as full, acceptable, or unacceptable function. RESULTS: The TRP was implanted in 60 femoral trochleae: 48 unilateral and 12 bilateral. Successful correction of patellar luxation was achieved in 59/60 cases. TRP was applied with other surgical techniques in 36/60 of the cases and as the only surgical procedure in 24/60 cases. Overall, three complications were observed: two minor and one major (patellar luxation recurrence). Neither implant loosening nor infection was observed. The mean radiographic follow-up was 3.8 months. At the time of the final follow-up, 57/60 cases were scored as fully functional. CONCLUSION: The TRP application either alone or in combination with other surgical techniques allowed for correction of patellar luxation and improvement in preoperative lameness with nominal complications. TRP could represent a potentially reliable alternative to trochleoplasty.

Retrospective evaluation and review of approaches for nonspecific lameness in dogs presented to an emergency service (2013-2014): 134 cases.

OBJECTIVE: This retrospective study aimed to characterize and evaluate the emergency approach, diagnosis, management, treatment, and follow-up of nonspecific canine lameness cases. DESIGN: Retrospective case series from September 25, 2013 to September 25, 2014. SETTING: The study was conducted at an urban university teaching hospital. ANIMALS: A consecutive sample of dogs presenting to the emergency service with nonspecific lameness in the designated timeframe was used to identify 134 cases. Owners were contacted to participate in the follow-up survey; dogs that died prior to data collection were excluded from the survey. Medical records were reviewed for lameness localization, etiology of lameness, diagnostics obtained, medications prescribed, and owner recommendations. INTERVENTIONS: Based on review of the medical records, the lameness localization, presumptive source of lameness (joint, soft tissue, neurological, or bone), diagnostics obtained, medications prescribed, and owner recommendations were recorded. Survey data included duration of lameness, perceived response to treatment, and activity level. MEASUREMENTS AND MAIN RESULTS: Definitive diagnoses were not assigned in 88.8% of lameness cases. A presumptive diagnosis of soft tissue injury was assigned in 45.3% of cases. Single limb lameness was more prevalent than multiple limb lameness. Owners whose dogs were treated with medication were significantly more likely to report that the lameness resolved (P = 0.049). Dogs with injury localized to ≥1 of the joints were significantly less likely to have resolution of lameness (P = 0.037). Treatment recommendations were predominantly pain control and activity restriction. CONCLUSIONS: Nonspecific lameness represents approximately 4% of canine urban emergency cases. Highlighting the points of clinical care considerations in understanding the etiology of lameness in dogs represents an opportunity for improved patient care and growth in emergency referral and follow-up.

The efficacy of injecting a distillate of the pitcher plant (Sarraceniaceae) adjacent to the palmar digital nerves of horses to ameliorate lameness caused by digital pain.

This study aimed to determine the efficacy of instilling extract of the pitcher plant around the palmar digital nerves of horses to ameliorate digit pain causing lameness. Five mixed breed horses were recruited. Horses were determined to be lame because of pain in the distal portion of one or both thoracic limbs by a positive response to a basisesamoid nerve block using 2%^mepivacaine hydrochloride. Gait was evaluated pre- and post-nerve block at 30 min, 3, 7,14 and 21 days. At the 3-week evaluation, the basisesamoid nerve block was repeated using the extract, and the gait was evaluated at similar times. Lameness was evaluated objectively using a wireless, inertial, sensor-based, motion analysis system. The basisesamoid nerve block significantly ameliorated lameness at 30 min when gait was evaluated, but it had no significant effect on lameness after this time. The product containing extract of the pitcher plant had no significant effect on lameness when administered as a basisesamoid nerve block at any time. Extract of the pitcher plant administered adjacent to the medial and lateral palmar digital nerves (i.e., a basisesamoid nerve block) had no efficacy in ameliorating lameness in the distal portion of one or both thoracic limbs. Extract of the pitcher plant likely has no value for treating horses for chronic pain when administered as a regional nerve block.

Routine hoof-trimming data provides insight into the occurrence of claw lesions in Holstein herds in the central region of South Africa.

Claw lesions in dairy cows contribute significantly to lameness, causing distress and discomfort for affected cows and raising welfare concerns. Despite increased awareness, lameness incidence continues to rise. Defining and recording claw traits are particularly problematic. In South Africa (SA), claw data is limited to paper-based records kept by private hoof trimmers. This research analysed claw-trimming data from five dairy farms over 6 years to examine the occurrence and recording of claw lesions in SA Holstein cattle. Lesion identification followed the Claw Lesion Identification in Dairy Cattle brochure. Among the recorded lesions, digital dermatitis (DD) had the highest prevalence (64.02%), followed by sole ulcers (SU; 8.59%), white line disease (WLD; 6.27%), and sole haemorrhage (SH; 4.28%), and most lesions occurred in the rear feet. Chi-square tests and correspondence analysis (CA) were employed to explore the relationships between lesions, feet, and housing. Results indicated that the prevalence of SU and SH showed high similarity for foot and lesion association, and that these were more highly associated with the rear feet. Additionally, the prevalence of DD and interdigital phlegmon were strongly associated, and closely associated with SU, and all these lesions were associated with both dirt lot and free-stall housing systems. CA further confirmed a close association between WLD and SH, and the prevalence of these lesions in the combination housing system. Results of this study highlight the complexity of lesion data and that specific associations between lesions could lead to simplifying the recording thereof. Consolidating the most informative claw lesions into categories will aid in the practical prevention, management, and treatment of lameness on-farm.

Percutaneous ultrasonic debridement of equine tendinopathy and desmopathy: A report of 10 cases.

Background: Tendinopathy and desmopathy are significant causes of morbidity in horses. Aim: To evaluate the use of percutaneous ultrasonic debridement (PUD) as a treatment for chronic tendinopathy and desmopathy in the horse. Methods: Eight adult horses with 10 affected limbs presented for lameness, ranging from 60-700 days postinjury. Diagnostic ultrasound identified the following: suspensory branch desmitis (n = 1), suspensory body desmitis (n = 2), Achilles tendinopathy (n = 1), desmitis of the accessory ligament of the deep digital flexor (DDF) tendon (n = 1), DDF tendinopathy (n = 2), and superficial digital flexor tendinopathy (n = 3). All horses had demonstrated lameness ranging from grade 1 to 4 [American Association of Equine Practitioners (AAEP) scale], with a mean pretreatment grade of 2.7. All horses underwent PUD using the Tenex Health TX® System. Results: Follow-up results were available from 6 to 41 months (mean, 23.2 months). Follow-up ultrasound imaging demonstrated improvement in fiber alignment and architectural change in all cases. All horses had a reduction in lameness from the treated tendon or ligament (AAEP grade 0-1; mean AAEP grade, 0.2) following a single treatment; lameness completely resolved in 8 of 10 treated limbs. No adverse events occurred in any case. No horses in this study developed a recurrence of their original lesion. Conclusion: Horses in this study demonstrated improvement following the PUD procedure. The procedure was well-tolerated and safe. Removal of tendinopathic scar tissue with PUD resulted in a return to function and without recurrence of the original lesion in all horses.

Prevalence of lameness on pasture-based New Zealand dairy farms: An observational study.

To understand the current impact of lameness on a system, it is important to define lameness prevalence across a range of dairy farms in that system. Prevalence estimates from dairy systems where cows are permanently managed at pasture are uncommon, although the limited data suggest that they have a lower lameness prevalence than housed cattle. One hundred and 20 farms from eight of the major dairying regions of New Zealand were randomly enrolled into a cross-sectional lameness prevalence study. On each of the farms, trained observers lameness scored cattle on two occasions, between October-December (spring, coinciding with peak lactation for most farms) and between January-March (summer, late lactation for most farms). At each visit, all lactating animals were scored using a four-point 0-3 scoring system, and included animals that had previously been identified as lame by the farmer. Animals with a lameness score (LS) ≥2 were defined as lame. Mixed logistic regression models assessed the interaction between region and season and island and season, respectively, and differences between the lameness prevalence within farm across the two seasons reported descriptively. A total of 116,317 locomotion scores over two events were conducted across the 120 farms. At the spring scoring event, 2128/60,007 (3.5 %) cows had a LS ≥2 and 1868/56,310 (3.3 %) cows had a LS ≥ 2 at the summer scoring event. At the farm level, across both scoring events, median lameness prevalence was 2.8 (interquartile range 1.5 - 4.5) %, with a range of 0.0-17.0 %. The median farm-level prevalence of LS = 3 was 0.5 % with a range of 0-4.6 %. The effect of timing of scoring was modified by region (p < 0.001), and island (p = 0.006) and at the individual farm level, differences between spring and summer farm level lameness prevalence were generally small (interquartile range: -1.8 to 1.0 %) but potentially large on individual farms (range from -12.3 % to 7.6 %). The median farm-level lameness prevalence estimate of 2.8 % across a random representative sample of New Zealand dairy farms give confidence that the overall prevalence of cattle lameness on New Zealand dairy farms is low. This adds to the growing evidence that pasture is a good management system with respect to hoof health. The evidence of strong seasonality of lameness was lacking. Instead of using lameness scoring to identify farms with large lameness problems, lameness scoring should be encouraged to farmers as a tool to improve the identification of lame animals.

[Diagnostic procedures and treatment of a ventromedial coxofemoral luxation in sheep - Surgery and open reposition of a ventromedial coxofemoral luxation with a toggle-pin and iliofemoral sling fixation]. / Diagnostik und Therapie bei der Hüftgelenksluxation des Schafes.

A 2.5-year-old female Valais black-nosed sheep was referred to the University Clinic for Ruminants at the University of Veterinary Medicine Vienna, with a history of sudden lameness after shearing. The sheep showed a moderate mixed lameness of the right hind limb, the hip joint area was painful on palpation; the pelvic limb was presented as stretched as possible. After the clinical examination, the suspected diagnosis of a right-sided hip joint dislocation was made, which was subsequently confirmed radiologically (luxatio ossis femoris dextra to caudoventral and medial). An open, manual reposition was performed under general anesthesia. A toggle pin was used as a prosthetic ligament replacement for the femoral head ligament, further stabilization was achieved by means of an iliofemoral loop fixation within the fascia of the gluteal muscles.The movement possibilities of the sheep during the postoperative healing phase were severely restricted and 8 weeks of stall rest were ensured. The healing process was uncomplicated. Telephone enquiry 6 months following the surgical intervention revealed that the sheep was free of lameness, kept up with the herd, and displayed a normal general condition.The success of surgery and the use of the procedure in livestock practice is limited by the necessity of rapid intervention after the trauma has occurred, the willingness of the animal owner to bear the costs associated with the operation under general anesthesia as well as to ensure the long post-operative follow-up care with controlled restriction of movement.

Perivascular wall tumour presenting as pastern mass in a Standardbred gelding.

A 2-year-old Standardbred gelding was referred for a mass on the palmaromedial right front pastern which was accompanied by progressively worsening lameness. The mass was firm to palpation and covered by normal skin. Ultrasonographically, a smooth encapsulated mass was present, medial to the flexor tendons and palmar to the neurovascular bundle. Because of a poor prognosis for future athletic performance without surgical or chemotherapeutic intervention and economic constraints preventing further diagnostics and treatment, the horse was euthanised. Post-mortem magnetic resonance imaging, histopathology and immunohistochemistry revealed the mass to be a perivascular wall tumour, the first record of such a neoplasia in the horse.