Gross, computed tomographic, and endoscopic anatomy of the equine carpal extensor tendon sheaths.

OBJECTIVE: (1) To describe the computed tomography (CT) and gross anatomy of the equine extensor carpi radialis sheath (ECRS) and common digital extensor sheath (CDETS); (2) to describe a single-portal endoscopic examination of the ECRS and CDETS. STUDY DESIGN: Ex vivo experimental. SAMPLE POPULATION: Thirty clinically normal cadaver thoracic equine limbs severed at the humeral diaphysis. METHODS: Ten limbs underwent plain and intrathecal contrast CT examinations and gross dissection of the ECRS and CDETS. Single-portal endoscopic examination of ECRS and CDETS was attempted in 4 limbs and endoscopic examination was performed on 16 limbs. Endoscopic video recordings were reviewed by 3 observers for quality of visualization before dissection and examination for iatrogenic damage. Interobserver agreement for ECRS and CDETS visualization was determined with Fleiss' κ agreement. RESULTS: Extensor carpi radialis sheath and CDETS anatomy was consistent between gross dissection and CT examinations. The ECRS endoscopic portal was medial at the level of the intersection between the extensor carpi obliquus and extensor carpi radialis tendon. The CDETS endoscopic portal was lateral, 5 cm proximal to the lateral styloid process of the ulna. The ECRS and CDETS were well visualized and interobserver agreement was substantial (κ = .73; P < .0001) and moderate (κ = .53; P < .0001), respectively. CONCLUSION: Computed tomography examinations provided useful anatomical information, consistent with gross dissection of the ECRS and CDETS. The described single-portal endoscopic techniques allowed consistent tenoscopic examination of the majority of the ECRS and CDETS. CLINICAL SIGNIFICANCE: Awareness of the intrathecal anatomy of the ECRS and CDETS should facilitate the treatment of these tendon sheaths. The proposed portals provide good to excellent single-site endoscopic visualization of the majority of the ECRS and CDETS.

Concentration of dipotassium ethylenediaminetetraacetic acid but not lithium heparin affects total protein determination in equine synovial fluid.

BACKGROUND: Refractometric determination of total protein (TP) in synovial fluid (SF) is commonly used for diagnosis and monitoring of synovial sepsis in horses. Previous studies have shown that elevated concentrations of certain anticoagulants may overestimate refractometric determination of TP concentration. OBJECTIVES: The aim of the study was to evaluate the effect of different concentrations of dipotassium EDTA (K2EDTA) and lithium heparin (LH) on TP determination by using a hand-held refractometer in equine synovial fluid. STUDY DESIGN: Cross-section observational study. METHODS: Thirty samples of synovial fluid obtained from 22 horses with different synovial conditions were collected. Synovial fluid samples were separated into different aliquots and placed in commercially available collection tubes containing K2EDTA or LH at four different concentrations (1.76, 3.52, 7.04 and 17.6 mg/ml for K2EDTA; 16, 32, 64 and 160 IU/ml for LH) . Refractometric TP determination was performed on untreated and K2EDTA and LH aliquots with a hand-held refractometer and by spectophotometric Biuret method as the gold standard. RESULTS: Refractometric TP determination was overestimated in SF samples containing 10 times the recommended K2EDTA concentrations. Lower concentrations of K2EDTA and LH concentrations did not affect refractometric TP determinations. MAIN LIMITATIONS: Limited number of samples mostly obtained from large synovial structures. CONCLUSION: To avoid incorrect TP determination, the use of LH containing collection tubes may be an appropriate alternative when the SF volume available is not enough to fill the K2EDTA collection tube.

Optimization of Synovial Fluid Collection and Processing for NMR Metabolomics and LC-MS/MS Proteomics.

Synovial fluid (SF) is of great interest for the investigation of orthopedic pathologies, as it is in close proximity to various tissues that are primarily altered during these disease processes and can be collected using minimally invasive protocols. Multi-"omic" approaches are commonplace, although little consideration is often given for multiple analysis techniques at sample collection. Nuclear magnetic resonance (NMR) metabolomics and liquid chromatography tandem mass spectrometry (LC-MS/MS) proteomics are two complementary techniques particularly suited to the study of SF. However, currently there are no agreed upon standard protocols that are published for SF collection and processing for use with NMR metabolomic analysis. Furthermore, the large protein concentration dynamic range present within SF can mask the detection of lower abundance proteins in proteomics. While combinational ligand libraries (ProteoMiner columns) have been developed to reduce this dynamic range, their reproducibility when used in conjunction with SF, or on-bead protein digestion protocols, has yet to be investigated. Here we employ optimized protocols for the collection, processing, and storage of SF for NMR metabolite analysis and LC-MS/MS proteome analysis, including a Lys-C endopeptidase digestion step prior to tryptic digestion, which increased the number of protein identifications and improved reproducibility for on-bead ProteoMiner digestion.

Can blood serum amyloid A concentrations in horses differentiate synovial sepsis from extrasynovial inflammation and determine response to treatment?

BACKGROUND: Serum amyloid A (SAA) concentrations in blood and synovial fluid of horses with synovial sepsis have diagnostic value. Studies suggest serial blood SAA measurements could act as a prognostic indicator. This study evaluated the use of serial blood SAA concentrations for monitoring of horses with synovial sepsis. METHODS: A prospective clinical trial was performed of horses referred to a single hospital with synovial sepsis that survived (n=17), synovial sepsis that were euthanised (n=5), non-septic intrasynovial pathologies (n=14) or extensive extrasynovial lacerations (n=5). SAA concentrations were determined on admission and every 24 hours thereafter. The area under the concentration-time curve from 0 to 144 hours of each group was compared by Kruskal-Wallis and post hoc Dunn's tests (P<0.05). RESULTS: Significant difference in mean blood concentration of SAA was found between synovial sepsis that survived and non-septic pathologies in the first 48 hours, as well as between non-septic intrasynovial pathologies and non-responsive sepsis requiring euthanasia. No difference was found between extensive extrasynovial lacerations and any septic group. CONCLUSIONS: While serial blood SAA is useful for monitoring clinical response of intrasynovial septic pathologies, interpretation should consider other clinical findings since blood SAA is not a specific marker for synovial sepsis.

The synovial fluid proteome differentiates between septic and nonseptic articular pathologies.

Articular conditions are common in horses and can result in loss of function, chronic pain and/or inability to work. Common conditions include osteoarthritis, osteochondrosis and synovial sepsis, which can be life-threatening, but despite the high clinical prevalence of these conditions, rapid and specific diagnosis, monitoring and prognostication remains a challenge for practicing veterinarians. Synovial fluid from a range of arthropathies was enriched for low abundance proteins using combinatorial peptide ligand ProteoMiner™ beads and analysed via liquid chromatography-tandem mass spectrometry. Changes in protein abundances were analysed using label-free quantification. Principle component analysis of differentially expressed proteins identified groupings associated with joint pathology. Findings were validated using ELISA. Lactotransferrin (LTF) abundance was increased in sepsis compared to all other groups and insulin-like growth factor-binding protein 6 (IGFBP6) abundance decreased in sepsis compared to other disease groups. Pathway analysis identified upregulation of the complement system in synovial joint sepsis and the downregulation of eukaryotic translation initiation factors and mTOR signalling pathways in both OA and OC compared to the healthy group. Overall, we have identified a catalogue of proteins which we propose to be involved in osteoarthritis, osteochondrosis and synovial sepsis pathogenesis. SIGNIFICANCE: Osteoarthritis, osteochondrosis and synovial sepsis, which can be life-threatening, are common articular conditions in which rapid and specific diagnosis, monitoring and prognostication remains a challenge for practicing veterinarians. This study has identified that the equine synovial fluid proteome exhibits distinctive profile changes between osteoarthritis, osteochondrosis, synovial sepsis and healthy joints. Elevated synovial abundance of lactotransferrin and decreased insulin-like growth factor-binding protein 6 were both found to distinguish synovial sepsis from all other study groups. Thus, these protein markers may have a future role in clinical practice to enable an earlier and reliable diagnosis of synovial sepsis.

Catastrophic musculoskeletal injuries in Thoroughbred racehorses on racetracks in Gauteng, South Africa.

The incidence and types of catastrophic musculoskeletal injuries in Thoroughbreds that resulted in euthanasia on selected racetracks in South Africa between 1998 and 2012 were investigated by an observational retrospective investigation. Data from the National Horseracing Authority of Southern Africa for these racetracks were used to calculate incidence rates in Thoroughbreds (n = 114) that sustained catastrophic musculoskeletal injuries during racing that required immediate euthanasia, based on the diagnosis made by the on-site veterinarian as well as on fetlock radiographs and dissections of 53 cadaver limbs of horses that sustained a catastrophic musculoskeletal injury. The proximal sesamoid bones and the distal suspensory ligament were involved in 55.26% of horses; 73.58% of the cadaver limb radiographs were of the left forelimb, 64.15% were closed fractures, and 74.47% had biaxial proximal sesamoid bone fractures. Catastrophic musculoskeletal injuries occurred almost exclusively unilaterally and involved mostly the left front leg. The average incidence rate for a catastrophic musculoskeletal injury occurring in a year at any of the tracks was 0.6 of 1000 starts.

Synovial Fluid Metabolites Differentiate between Septic and Nonseptic Joint Pathologies.

Osteoarthritis (OA), osteochondrosis (OC), and synovial sepsis in horses cause loss of function and pain. Reliable biomarkers are required to achieve accurate and rapid diagnosis, with synovial fluid (SF) holding a unique source of biochemical information. Nuclear magnetic resonance (NMR) spectroscopy allows global metabolite analysis of a small volume of SF, with minimal sample preprocessing using a noninvasive and nondestructive method. Equine SF metabolic profiles from both nonseptic joints (OA and OC) and septic joints were analyzed using 1D 1H NMR spectroscopy. Univariate and multivariate statistical analyses were used to identify differential metabolite abundance between groups. Metabolites were annotated via 1H NMR using 1D NMR identification software Chenomx, with identities confirmed using 1D 1H and 2D 1H 13C NMR. Multivariate analysis identified separation between septic and nonseptic groups. Acetate, alanine, citrate, creatine phosphate, creatinine, glucose, glutamate, glutamine, glycine, phenylalanine, pyruvate, and valine were higher in the nonseptic group, while glycylproline was higher in sepsis. Multivariate separation was primarily driven by glucose; however, partial-least-squares discriminant analysis plots with glucose excluded demonstrated the remaining metabolites were still able to discriminate the groups. This study demonstrates that a panel of synovial metabolites can distinguish between septic and nonseptic equine SF, with glucose the principal discriminator.

Effects of stanozolol on normal and IL-1ß-stimulated equine chondrocytes in vitro.

BACKGROUND: Intra-articular administration of stanozolol has shown promising results by improving the clinical management of lameness associated with naturally-occurring osteoarthritis (OA) in horses, and by decreasing osteophyte formation and subchondral bone reaction in sheep following surgically induced OA. However, there is limited evidence on the anti-inflammatory and modulatory properties of stanozolol on articular tissues. The objective of the current study was to evaluate the effects of stanozolol on chondrocyte viability and gene expression in normal equine chondrocytes and an inflammatory in vitro system of OA (interleukin-1ß (IL-1ß) treated chondrocytes). RESULTS: Chondrocytes from normal metacarpophalangeal joints of skeletally mature horses were exposed to four treatment groups: (1) media only (2) media+IL-1ß (3) media+IL-1ß + stanozolol (4) media+stanozolol. Following exposure, chondrocyte viability and the expression of catabolic, anabolic and structural genes were determined. General linear models with Dunnet's comparisons with Bonferroni's adjustment were performed. Cell viability was similar in all groups. Stanozolol treatment reduced gene expression of MMP-13, MMP-1, IL-6 and COX-2 in both normal and IL-1ß treated chondrocytes. Stanozolol treatment reduced ADAMTS4 gene expression in normal chondrocytes. Stanozolol reduced the expression of COL2A1. CONCLUSIONS: The current study demonstrates stanozolol has chondroprotective effects through downregulation of genes for pro-inflammatory/catabolic cytokines and enzymes associated with OA. However, there is no evidence of increased cartilage stimulation through upregulation of the anabolic and structural genes tested.

Are serum amyloid A or D-lactate useful to diagnose synovial contamination or sepsis in horses?

Synovial sepsis in horses is life threatening and accurate diagnosis allowing prompt treatment is warranted. This study assessed the diagnostic value of serum amyloid A (SAA) and D-lactate in blood and synovial fluid (SF) as diagnostic markers of synovial sepsis in horses and correlated them with total nucleated cell count (TNCC), percentage of neutrophils (%N) and total protein (TP) in SF. Blood and SF SAA and D-lactate concentrations were determined in a case-control observational study including 112 horses (38 with synovial contamination or sepsis (SCS), 66 with non-septic intra-synovial pathology (NSISP) and 8 controls). Blood and SF SAA were significantly higher in SCS than in NSISP and control horses. SAA values were similar in NSISP and control horses. SF SAA was moderately correlated with synovial TNCC, TP and blood SAA. Blood and SF SAA were 82.4 per cent and 80 per cent sensitive and 88.9 per cent and 73 per cent specific for diagnosis of SCS, with cut-off values of 60.7 and 1.14 µg/ml, respectively. Blood and SF D-lactate concentrations were not significantly different between groups. This study shows that blood and SF SAA concentrations can aid to distinguish SCS from non-septic synovial pathology; however, D-lactate was not useful.

Effect of Arthroscopic Lavage on Systemic and Synovial Fluid Serum Amyloid A in Healthy Horses.

OBJECTIVE: To evaluate the effect of arthroscopic lavage on systemic serum amyloid A (SAA) and SAA, total protein, nucleated cell count, and percentage of neutrophils in synovial fluid in healthy horses. STUDY DESIGN: Prospective experimental study. ANIMALS: Healthy adult horses (n = 6). METHODS: Middle carpal joints were randomly assigned to 1 of 2 treatments: arthrocentesis (controls) or arthroscopic lavage, with 30 day washout period between treatments. Synovial fluid and blood samples were collected at 0, 24, 48, 72, 96, and 120 hours. Measurements included systemic and synovial fluid SAA, as well as total protein, nucleated cell count, and percentages of neutrophils in synovial fluid. Data were analyzed by median quantile regression and Wilcoxon signed-rank test and significance level set at P < .05. RESULTS: Systemic and synovial fluid SAA did not increase from baseline (except systemic SAA at 24 hours for both treatments) and were not significantly different between treatments. Total protein values were significantly increased after arthroscopic lavage (except at 96 hours) but not in controls at all time points. With both treatments, nucleated cell counts significantly increased from baseline values at all time points. Percentages of neutrophils were significantly increased after arthroscopic lavage at all time points, but only at 24 hours in controls. CONCLUSION: Total protein, nucleated cell count, and percentage of neutrophils in synovial fluid were significantly increased after arthroscopic lavage; however, synovial fluid SAA was not affected by this procedure. Further research is warranted to validate synovial fluid SAA as a monitoring tool during treatment of septic arthritis.

Transthecal Arthroscopy of the Palmar Distal Interphalangeal Joint in the Horse: A Cadaver Study.

OBJECTIVE: To describe a transthecal approach to the palmar pouch of the distal interphalangeal joint (DIPJ) in horses and compare it with the conventional blind arthroscopic technique. STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Cadaver forelimbs (n = 26 pairs) from mature horses. METHODS: One limb from each pair was randomly assigned to each arthroscopic approach (conventional or transthecal). The conventional arthroscopic approach was performed as previously described and the transthecal approach was performed through sharp dissection of the distal reflection of the digital flexor tendon sheath (DFTS). The proportion (0-100%) of the navicular bone, palmar aspect of the condyles of the 2nd phalanx, collateral sesamoidean ligaments, and palmar synovial pouches of the DIPJ visualized by each approach was estimated. Limbs were dissected and iatrogenic damage of relevant structures was assessed. Nondirectional Mann-Whitney U-test was used to compare groups. Significance was set at P < .05. RESULTS: The transthecal approach provided greater visualization of the navicular bone (P < .001), palmar aspect of the 2nd phalanx (P < .001), and palmar synovial pouches of the DIPJ (P < .001) than the conventional approach. There were no significant differences in iatrogenic damage between approaches. CONCLUSION: The transthecal approach provides improved visualization of the palmar aspect of the DIPJ compared to the conventional blind approach and may be useful in nonseptic conditions of the DIPJ. However, because of the creation of communication with the DFTS, use of the transthecal approach for suspected synovial sepsis of the DIPJ may be contraindicated.

Laparoscopic vasectomy in African elephants (Loxodonta africana).

OBJECTIVE: To describe a surgical technique for, and outcome after, laparoscopic vasectomy of free-ranging elephants. STUDY DESIGN: Case series. ANIMALS: African elephants (Loxodonta africana; n = 14). METHODS: Male elephants (12-35 years old) were anesthetized with etorphine and supported in a sling in a modified standing position, and positive pressure ventilated with oxygen. Anesthesia was maintained with IV etorphine. Vasectomy was performed under field conditions by bilateral, open-approach, flank laparoscopy with the abdomen insufflated with filtered ambient air. A 4-cm segment of each ductus deferens was excised. Behavior and incision healing were recorded for 8 months postoperatively. RESULTS: Successful bilateral vasectomy (surgical time, 57-125 minutes) was confirmed by histologic examination of excised tissue. Recovery was uneventful without signs of abnormal behavior. Large intestine lacerations (3 elephants; 1 full and 2 partial thickness) were sutured extracorporeally. One elephant found dead at 6 weeks, had no prior abnormal signs. Skin incisions healed without complication. CONCLUSIONS: Laparoscopic vasectomy can be performed in African elephants in their natural environment.

Analgesic and motor effects of a high-volume intercoccygeal epidural injection of 0.125% or 0.0625% bupivacaine in adult cows.

The objectives of this study were to determine the analgesic and motor effects of a high-volume intercoccygeal epidural injection of bupivacaine at 2 concentrations in cows. A prospective, randomized, blinded, crossover trial was conducted on 6 adult cows. An indwelling epidural catheter was placed in the first intercoccygeal space and advanced 10 cm cranially. All the cows received 3 treatments with a washout period of 48 h: saline (control), 0.125% bupivacaine (high dose), or 0.0625% bupivacaine (low dose), at a final volume of 0.15 mL per kilogram of body weight, infused manually into the epidural space over a period of 15 min. The anal and tail tone and motor deficits of the pelvic limbs were evaluated in 5 of the cows with use of a numerical rating scale and a visual analogue scale (VAS). Sensory block was assessed in 4 of the cows by the response to needle pricks in different regions with the use of a VAS. Measurements were obtained before and at different time points after injection, up to 360 min. Analysis of variance for repeated measures and post-hoc Tukey's and Dunnett's tests were used. Differences were considered significant when the P-value was ≤ 0.05. One cow became recumbent 6 h after injection. Anal and tail tones were significantly decreased and motor deficits of the pelvic limbs were significantly increased after bupivacaine treatment compared with control treatment. The overall mean VASpain scores ± standard deviation were 66 ± 8 after control treatment, 52 ± 5 after low-dose bupivacaine treatment, and 43 ± 5 after high-dose bupivacaine treatment. The pain scores were significantly lower in caudal regions up to the saphenous nerve after high-dose bupivacaine treatment compared with control treatment and significantly lower in the anus, vulva, and tail after low-dose bupivacaine treatment compared with control treatment. Thus, analgesia with moderate motor deficits of the pelvic limbs may be obtained with 0.125% bupivacaine administered epidurally.

Les objectifs de la présente étude étaient de déterminer chez la vache les effets analgésiques et moteurs d'une injection épidurale inter-coccygienne d'un volume important de bupivacaïne à deux concentrations. Une étude croisée prospective, randomisée, et à l'aveugle a été réalisée chez 6 vaches adultes. Un cathéter épidural à demeure a été placé dans le premier espace inter-coccygien et avancé cranialement de 10 cm. Toutes les vaches ont reçu 3 traitements avec une période d'évacuation de 48 h : saline (témoin), 0,125 % de bupivacaïne (dose élevée) ou 0,0625 % de bupivacaïne (faible dose), à un volume final de 0,15 mL par kilo de poids corporel, infusé manuellement dans l'espace épidural sur une période de 15 min. Le tonus anal et de la queue ainsi que les déficits moteurs des membres pelviens ont été évalués chez 5 des vaches au moyen d'une échelle numérique de pointage et une échelle analogue visuelle (VAS). Le bloc sensitif a été évalué chez 4 des vaches par la réponse à des piqûres d'aiguille dans différentes régions avec l'utilisation d'une VAS. Les mesures ont été obtenues avant et à différents temps après l'injection, jusqu'à 360 min. Une analyse de variance pour mesures répétées et les tests post-hoc de Tukey et de Dunnett ont été utilisés. Les différences étaient considérées significatives lorsque la valeur de P était ≤ 0,05. Une vache est demeurée couchée 6 h après l'injection. Le tonus anal et de la queue était réduit de manière significative et les déficits moteurs des membres pelviens étaient significativement augmentés après le traitement à la bupivacaïne comparativement au traitement témoin avec la saline. Dans l'ensemble les scores moyens ± l'écart-type de VASdouleur étaient 66 ± 8 après le traitement témoin, 52 ± 5 après le traitement à faible dose de bupivacaïne, et 43 ± 5 après le traitement avec la dose élevée de bupivacaïne. Les scores de douleur étaient significativement plus faibles dans les régions caudales jusqu'au nerf saphène après le traitement avec les doses élevées de bupivacaïne comparativement au traitement témoin et significativement plus faibles au niveau de l'anus, la vulve et la queue après le traitement avec les faibles doses de bupivacaïne comparativement au traitement témoin. Ainsi, une analgésie avec des déficits moteurs modérés des membres pelviens peut être obtenue avec de la bupivacaïne à 0,125 % administrée par voie épidurale.(Traduit par Docteur Serge Messier).

Surgical stabilization of shoulder luxation in a pot-bellied pig.

Case Description-A 4.6-month-old pot-bellied pig was evaluated because of non-weight-bearing lameness (grade 5/5) in the right forelimb of 4 days' duration. Clinical Findings-Clinical and radiographic examination revealed a closed, lateral luxation of the right shoulder joint. Treatment and Outcome-Initial attempts at closed reduction failed to provide adequate stability of the shoulder joint. Open reduction and internal fixation by placement of 2 lateral tension sutures with a system designed for canine cranial cruciate ligament repair provided adequate joint stability and a successful outcome. Conclusions and Clinical Relevance-Stabilization of the shoulder joint with lateral tension sutures after open reduction should be considered for management of lateral shoulder luxation in pot-bellied pigs.

Clinical use of antimicrobial regional limb perfusion in horses: 174 cases (1999-2009).

OBJECTIVE: To describe the clinical use of regional limb perfusion with antimicrobials (A-RLP), complications, and outcome in a large series of patients. DESIGN: Retrospective case series. ANIMALS: 174 horses. PROCEDURES: Medical records of horses treated with A-RLP between 1999 and 2009 were reviewed. Signalment, primary complaint, horse use, etiology, duration of clinical signs, previous treatment, structures involved, concurrent conditions, A-RLP characteristics, additional treatments, complications, and outcome were recorded. At long-term follow-up, 2 outcomes were investigated: survival rate and return to previous use at the same or higher level. Univariate and multivariate logistic regression analyses were conducted. RESULTS: Group 1 (96 horses) included septic synovitis. Group 2 (50 horses) included extrasynovial lacerations (23 horses) and fresh, minimally contaminated intrasynovial lacerations without evidence of established synovial infection (27 horses). Group 3 (28 horses) included miscellaneous other conditions. Only minor complications were reported in 12.26% of horses that received IV (n = 155) and 33% of horses that received intraosseous (27) A-RLP. Horses with septic synovitis had a lower survival rate (53.43%) than did horses with lacerations (91.89%). Within group 2, no significant differences in short- or long-term outcomes were found between horses with extrasynovial and fresh, minimally contaminated intrasynovial lacerations. For the horses returning to previous use, 80% of horses with septic synovitis and 72.72% of horses with lacerations were performing at the same or higher level at the time of follow-up. CONCLUSIONS AND CLINICAL RELEVANCE: The results of the present study indicated that A-RLP is a safe technique with minimal adverse effects. The IV route presented fewer complications than intraosseous injection. Horses with infection of synovial structures had a lower survival rate than did those with acute, minimally contaminated intrasynovial lacerations. The latter had a similar prognosis for horses with extrasynovial lacerations treated with A-RLP.

Castration of the Vietnamese pot-bellied boar: 8 cases.

Surgical techniques for castration of the Vietnamese pot-bellied boar and outcome are described. Vietnamese pot-bellied pig (VPBP) boars (n = 8) were admitted for castration. Data retrieved from medical records (2002-2011) for these pigs included signalment, history, reason for castration, perioperative management, surgical technique, and complications. Follow-up information was obtained from owners. A scrotal approach with closed technique was used for 6 boars with normally descended testes. A scrotal approach and open technique was used in 1 inguinal cryptorchid boar. In a hemicastrated abdominal cryptorchid boar an ipsilateral parainguinal approach was used. No complications occurred. Castration of the Vietnamese pot-bellied boar is associated with minimal complications and a satisfactory cosmetic outcome. We recommend the routine closure of the external inguinal rings, a simple and fast procedure that may prevent post-castration inguinal herniation.Surgical techniques for castration of the Vietnamese pot-bellied boar and outcome are described. Vietnamese pot-bellied pig (VPBP) boars (n = 8) were admitted for castration. Data retrieved from medical records (2002­2011) for these pigs included signalment, history, reason for castration, perioperative management, surgical technique, and complications. Follow-up information was obtained from owners. A scrotal approach with closed technique was used for 6 boars with normally descended testes. A scrotal approach and open technique was used in 1 inguinal cryptorchid boar. In a hemicastrated abdominal cryptorchid boar an ipsilateral parainguinal approach was used. No complications occurred. Castration of the Vietnamese pot-bellied boar is associated with minimal complications and a satisfactory cosmetic outcome. We recommend the routine closure of the external inguinal rings, a simple and fast procedure that may prevent post-castration inguinal herniation.

RésuméCastration du Cochon vietnamien mâle: 8 cas. Les techniques chirurgicales pour la castration du Cochon vietnamien mâle et les résultats sont décrits. Des Cochons vietnamiens mâles (CV) (n = 8) ont été admis pour la castration. Les données récupérées des dossiers médicaux (de 2002 à 2011) pour ces cochons incluaient le signalement, l'anamnèse, la raison pour la castration, la gestion péri-opératoire, la technique chirurgicale et les complications. Les renseignements de suivi ont été obtenus auprès des propriétaires. Une approche scrotale avec une technique fermée a été utilisée pour 6 verrats avec des testicules descendus normalement. Une approche scrotale et une technique ouverte ont été utilisées chez un verrat cryptorchide inguinal. Chez un verrat cryptorchide abdominal hémicastré, une approche parainguinale homolatérale a été utilisée. Aucune complication ne s'est produite. La castration de Cochon vietnamien est associée à des complications minimes et à un résultat esthétique satisfaisant. Nous recommandons la fermeture de routine des anneaux inguinaux externes, une intervention simple et rapide qui peut prévenir l'herniation inguinale post-castration.(Traduit par Isabelle Vallières).

Analysis of the subchondral microarchitecture of the distopalmar aspect of the third metacarpal bone in racing Thoroughbreds.

OBJECTIVE: To determine the anisotropic characteristics of the microarchitecture of the subchondral bone (SCB) plate and trabecular bone (TBB) of the distopalmar aspect of the metacarpal condyles in horses with different stages of SCB disease. SAMPLE POPULATION: 12 third metacarpal bone pairs from racing Thoroughbreds euthanized for diverse reasons. PROCEDURES: Both metacarpi were collected from horses with SCB changes that were mild (sclerosis and focal radiolucencies; n=6) or severe (multifocal radiolucencies and articular surface defects; 6). Sample blocks of SCB plate and TBB were collected from the distopalmar aspect of both condyles and the sagittal ridge and examined via 3-D micro-computed tomography at 45-?m isotropic voxel resolution. For each sample, the angle between the principal orientation of trabeculae and the sagittal plane and the degree of anisotropy (DA) were calculated from mean intercept length measurements. RESULTS: Condylar samples had significantly lower angle (mean, 8.9°; range, 73° to 10.9°) than sagittal ridge samples (mean, 40.7°; range, 33.6° to 49.2°), TBB had significantly higher DA (mean±SE, 1.75±0.04) than SCB plate (1.29±0.04), and mildly diseased TBB had higher DA (1.85±0.06) than severely diseased TBB (1.65±0.06). CONCLUSIONS AND CLINICAL RELEVANCE: The highly ordered appearance of trabeculae within the condyles supports the concept that joint loading is primarily transmitted through the condyles and not the sagittal ridge. The sharp changes in the trajectories of the SCB trabeculae at the condylar grooves may be indicative of hypothetical tensile forces at this location contributing to the pathogenesis of condylar fractures.

Mechanical properties of subchondral bone in the distal aspect of third metacarpal bones from Thoroughbred racehorses.

OBJECTIVE: To characterize the mechanical properties of subchondral bone (SCB) of the distopalmar aspect of the condyles of the third metacarpal bone (MC3) and their correlations with structural aspects of MC3s in Thoroughbred racehorses. SAMPLE POPULATION: 12 pairs of MC3s from Thoroughbred racehorses euthanized for various reasons. PROCEDURES: MC3s were collected from horses with mild (n = 6) and with severe (6) SCB changes, as determined by micro-computed tomography (CT). Specimens of SCB plate and trabecular bone were cut from the distopalmar aspect of condyles and sagittal ridge and examined with 3-dimensional micro-CT. Specimens were tested in compression, and elastic modulus, yield stress, yield strain, and toughness were calculated. Apparent and true bone mineral density, bone volume fraction, trabecular thickness, trabecular separation, and connectivity were also calculated. Differences in mechanical properties among various classifications of bone were evaluated. Correlations between structural and mechanical variables were also assessed. RESULTS: No differences were detected between left and right forelimbs. Specimens from condyles had higher values for elastic modulus, yield stress, and toughness than did specimens of sagittal ridge. In SCB with severe changes attributable to SCB disease, SCB plate was weaker and trabecular bone was stronger than in SCB with mild changes. Microstructural and mechanical properties were significantly correlated. CONCLUSIONS AND CLINICAL RELEVANCE: A marked gradient in mechanical properties of SCB from horses, which could be involved in the pathogenesis of condylar fractures, was detected. Mechanical properties of SCB from the distal aspect of MC3s can be predicted to some extent via micro-CT.

Structural characterization of subchondral bone in the distal aspect of third metacarpal bones from Thoroughbred racehorses via micro--computed tomography.

OBJECTIVE: To characterize the microstructure of subchondral bone (SCB) plate and trabecular bone (TBB) of the distopalmar aspect of the condyles of third metacarpal bones (MC3s) from Thoroughbred racehorses at 2 different stages of SCB disease via micro-computed tomography (CT). SAMPLE POPULATION: 12 pairs of MC3s from Thoroughbred racehorses euthanized for various reasons. PROCEDURES: MC3s were collected from horses with mild (n = 6) or severe (6) SCB disease, as determined via micro-CT. Cubic (6 x 6 x 6-cm) specimens of SCB plate and TBB were cut from the palmar aspect of condyles and sagittal ridges and examined with 3-dimensional micro-CT. For each specimen, apparent bone mineral density (aBMD), true BMD (tBMD), bone volume fraction (BVF), trabecular thickness (TBT), trabecular separation (TBS), and connectivity (CN) were calculated. RESULTS: Condyles had higher aBMD, tBMD, BVF, and TBT and lower TBS than did the sagittal ridge. In bone specimens with mild SCB changes, SCB plate had higher aBMD, TBT, and CN and lower TBS than did TBB. In bone specimens with severe SCB disease, TBB had higher aBMD and TMD and lower TBS than it did in bone specimens with mild disease, and values were similar to those for SCB plate in bone specimens with severe disease. CONCLUSIONS AND CLINICAL RELEVANCE: The microstructure of SCB of the distopalmar aspect of metacarpal condyles of horses varied according to the severity of changes identified via micro-CT. With mild SCB disease, sclerosis existed in the SCB plate of the condyles; with severe disease, sclerosis also invaded condylar TBB.