Head and neck squamous cell carcinoma with heterotopic ossification, lymphovascular invasion, and nodal and pulmonary metastases in a 23-year-old Morgan gelding.

Primary squamous cell carcinoma of the head and neck occurs in the skin or squamous epithelial lining tissues of the oral cavity, pharynx, larynx, and sinonasal tract. Although it is a common tumor in horses, distant metastatic spread to the lung is rare. This report describes a case of metastatic pulmonary squamous cell carcinoma in a 23-year-old Morgan gelding. The clinical signs displayed by this gelding in some ways mimicked the typical presentation of equine multinodular pulmonary fibrosis or thoracic lymphoma. The postmortem diagnosis in this case was head and neck squamous cell carcinoma, but a primary site of origin could not be ascertained. Cancer-associated heterotopic ossification (HO) was also identified in this case; this is an exceedingly rare finding with equine pulmonary neoplasia. Key clinical message: Careful physical examination should be undertaken in all horses presenting with clinical signs of intrathoracic disease. Clinical and radiographic abnormalities in this case of pulmonary metastatic disease resembled some of those associated with interstitial pneumonia. Rarely encountered in domestic animal species, there has been only 1 previous report of HO in a case of oronasal carcinoma in a horse.

Carcinome épidermoïde de la tête et du cou avec ossification hétérotopique, envahissement lymphovasculaire et métastases ganglionnaires et pulmonaires chez un hongre Morgan de 23 ans. Le carcinome épidermoïde primitif de la tête et du cou survient dans la peau ou les tissus épithéliaux squameux de la cavité buccale, du pharynx, du larynx et du tractus naso-sinusien. Bien qu'il s'agisse d'une tumeur courante chez les chevaux, la propagation métastatique à distance au poumon est rare. Ce rapport décrit un cas de carcinome épidermoïde pulmonaire métastatique chez un hongre Morgan de 23 ans. Les signes cliniques présentés par ce hongre imitaient à certains égards la présentation typique de la fibrose pulmonaire multinodulaire équine ou du lymphome thoracique. Le diagnostic post-mortem dans ce cas était un carcinome épidermoïde de la tête et du cou, mais un site d'origine primaire n'a pas pu être déterminé. L'ossification hétérotopique associée au cancer (HO) a également été identifiée dans ce cas; il s'agit d'une découverte extrêmement rare avec la néoplasie pulmonaire équine.Message clinique clé :Un examen physique attentif doit être entrepris chez tous les chevaux présentant des signes cliniques de maladie intrathoracique. Les anomalies cliniques et radiographiques dans ce cas de maladie pulmonaire métastatique ressemblaient à certaines de celles associées à la pneumonie interstitielle. Rarement rencontré chez les espèces animales domestiques, il n'y a eu qu'un seul signalement antérieur d'HO dans un cas de carcinome oronasal chez un cheval.(Traduit par Dr Serge Messier).

Histologic evidence for a humoral immune response in synovitis associated with cranial cruciate ligament disease in dogs.

OBJECTIVE: To investigate histopathological features of synovium from dogs with cranial cruciate ligament disease (CCLD) to seek mechanisms of osteoarthritis (OA) associated with CCLD. STUDY DESIGN: Retrospective, single-institution case series. ANIMALS: Thirty client-owned dogs. METHODS: Synovial biopsies (n = 30) obtained from stifles with CCLD were assessed by using two synovitis histopathology grading systems (Krenn and Hospital for Special Surgery [HSS]). The Krenn synovitis score was interpreted as "no synovitis," "low-grade," or "high-grade," while inflammatory subtype (low, mixed, or high) was determined by a computational algorithm within the HSS system. Comparison of synovitis scores was based on degree of CCL rupture and presence of meniscal tears. RESULTS: Histopathological changes and synovitis scores were similar regardless of degree of rupture (partial n = 5, complete n = 25) or presence of meniscal injury (n = 12) and were characterized by hyperplastic and lymphoplasmacytic synovitis with increased vascularity (30/30) and the presence of hemosiderin deposits (28/30), binucleated plasma cells (28/30), mucoid change (25/30), and Mott cells (16/30). Thirteen (43%) specimens were consistent with high-grade synovitis according to the Krenn system, while 11 (37%) specimens fit into the high-inflammatory subtype with the HSS system. CONCLUSION: Synovitis associated with canine CCLD in this study population was lymphoplasmacytic and was often highly inflammatory, with the presence of cells pertaining to humoral immunity. Humoral immune responses may play key roles in the synovitis associated with CCLD. CLINICAL SIGNIFICANCE: Modulation of biological factors that provoke humoral immune responses may mitigate symptoms of OA that persist and progress even after surgical treatment of CCLD in dogs.

Comparison of biologic scaffolds for augmentation of partial rotator cuff tears in a canine model.

BACKGROUND: This study was designed to test the hypothesis that biologic scaffold augmentation of articular-sided partial-thickness supraspinatus tendon tears would be associated with superior functional, imaging, biomechanical, and histologic properties compared with untreated tears in a preclinical canine model. METHODS: With Institutional Animal Care and Use Committee approval, dogs (n = 16) underwent half-thickness resection of the articular portion of the supraspinatus tendon (SST). Defects were treated by débridement (DB) (n = 8) or scaffold augmentation on the bursal side using amnion matrix cord scaffold (AM) (n = 8), decellularized human dermal allograft (AF) (n = 8), or bovine collagen patch (RMP) (n = 8). Control dogs (n = 4; 8 normal shoulders) were included. Assessments included lameness, function, comfortable shoulder range of motion (CROM), pain, ultrasonography, magnetic resonance imaging (MRI), arthroscopy, gross examination, biomechanical testing, and histopathology. RESULTS: At 3 months, CROM was significantly lower and pain significantly higher in DB compared with all other groups. At 6 months, CROM was significantly lower and pain significantly higher in RMP compared with AM and AF, and AM and AF showed significantly less thickening than DB and RMP. AF had the least severe MRI pathology and AM had significantly less MRI pathology than DB. AF SSTs and biceps tendons showed the least severe histopathology, and AM SSTs showed significantly less histopathology than DB and RMP SSTs. CONCLUSION: Biologic scaffolds can be effective in augmenting healing of articular-sided partial-thickness SST tears when compared with débridement in a preclinical canine model. Decellularized human dermal allograft and amnion matrix cord may have advantages over the bovine collagen patch for use in this indication.

Radiologic and Histologic Evaluation of Proximal Bicep Pathology in Patients With Chronic Biceps Tendinopathy Undergoing Open Subpectoral Biceps Tenodesis.

PURPOSE: To correlate preoperative magnetic resonance imaging (MRI) and intraoperative anatomic findings within the proximal long head biceps tendon to histologic evaluation of 3 separate zones of the tendon in patients with chronic biceps tendinopathy. METHODS: Sixteen patients with chronic biceps tendinopathy were treated with open subpectoral biceps tenodesis. Preoperative MRI tendon grading was as follows: normal tendon, increased signal, tendon splitting, incomplete/complete tear. The removed portion of the biceps tendon was split into 3 segments: zone 1, 0-3.5 cm from the labral insertion; zone 2, 3.5-6.5 cm; and zone 3, 6.5-9 cm, and was histologically evaluated using the Bonar score. Tenosynovium adjacent to the tendon was assessed histologically using the Osteoarthritis Research Society International score. CD31, CD3, and CD79a immunohistochemistries were conducted to determine vascularization, T-cell infiltrates, and B-cell infiltrates, respectively. Analysis of variance and Pearson correlations were performed for statistical analysis. RESULTS: Preoperative MRI showed no significant differences in tendon appearance between zones 1-3. Intraoperative findings included nonspecific degenerative SLAP tears or mild/moderate biceps tenosynovitis in all cases. Significantly (P < .001) higher Bonar scores were noted for tendon in zones 1 (7.9 ± 1.8) and 2 (7.3 ± 1.5) compared with zone 3 (5.0 ± 1.1). Cell morphology scores in zone 1 (1.9 ± 0.4) and zone 2 (1.5 ± 0.6) were significantly higher than that in zone 3 (0.8 ± 0.3) (P < .05). Inflammatory tenosynovium showed weak correlation with tendon changes in zone 1 (r = 0.08), zone 2 (r = 0.03), or zone 3 (r = 0.1). CONCLUSIONS: In patients with chronic long head biceps tendinopathy who underwent open subpectoral tenodesis, MRI and intraoperative assessment did not show significant structural abnormalities within the tendon despite significant histopathologic changes. Severity of tendon histopathology was more pronounced in the proximal and mid-portions of the tendon. CLINICAL RELEVANCE: Proximal versus distal biceps tenodesis is a subject of frequent debate. This study contributes to the ongoing evaluation of the characteristics of the proximal biceps in this type of pathologic condition.

Meniscal biology in health and disease.

The knee is a fascinating yet complex joint. Researchers and clinicians agree that the joint is an organ comprised of highly specialized intrinsic and extrinsic tissues contributing to both health and disease. Key to the function and movement of the knee are the menisci, exquisite fibrocartilage structures that are critical structures for maintaining biological and biomechanical integrity of the joint. The biological/physiological functions of the menisci must be understood at the tissue, cellular and even molecular levels in order to determine clinically relevant methods for assessing it and influencing it. By investigating normal and pathological functions at the basic science level, we can begin to translate data to patients. The objective of this article is to provide an overview of this translational pathway so that progression toward improved diagnostic, preventative, and therapeutic strategies can be effectively pursued. We have thoroughly examined the pathobiological, biomarker, and imaging aspects of meniscus research. This translational approach can be effective toward optimal diagnosis, prevention, and treatment for the millions of patients who suffer from meniscal disorders each year.

Biologic Joint Repair Strategies: The Mizzou BioJoint Story.

Because articular cartilage has very limited healing potential, most symptomatic cartilage injuries eventually result in end-stage osteoarthritis and are treated with artificial joint replacement. Our interdisciplinary, comparative orthopedic research performed by a team of DVMs, MDs, engineers, and basic scientists has yielded marked progress toward effective biologic joint restoration strategies by bringing bench-side ideas to fruition in bedside applications in both canine and human patients. This mini-review summarizes the progress of biologic joint restoration strategies at our center.

Retinal astrocytoma in a dog.

A miniature schnauzer dog presenting with hyphema and glaucoma of the right eye had a retinal neoplasm. Neoplastic cells stained positively for glial fibrillary acidic protein, vimentin, and S-100 and largely negatively for oligodendrocyte transcription factor 2 by immunohistochemistry. The clinical and histopathological features of canine retinal astrocytomas are discussed.

Astrocytome rétinal chez un chien. Un chien Schnauzer miniature a été présenté avec de l'hyphéma et du glaucome dans l'oeil droit et avait un néoplasme rétinal. Les cellules néoplastiques ont donné un résultat positif par immunohistochimie pour la protéine fibrillaire gliale acide, la vimentine et S-100 et les résultats étaient en grande partie négatifs pour le facteur de transcription 2 des oligodendrocytes. Les caractéristiques cliniques et histopathologiques des astrocytomes rétinaux canins sont discutés.(Traduit par Isabelle Vallières).

INTESTINAL HISTOPLASMOSIS IN A CAPTIVE REINDEER (RANGIFER TARANDUS), MISSOURI, USA.

An infection with Histoplasma capsulatum was diagnosed in a farmed reindeer in Missouri, an endemic area for histoplasmosis, localized in the intestine. The intrahistiocytic organisms were identified in tissue sections using histologic methods and confirmed by immunohistochemistry. This is the first report of histoplasmosis in a reindeer or in any deer species.

Suspensory Versus Interference Screw Fixation for Arthroscopic Anterior Cruciate Ligament Reconstruction in a Translational Large-Animal Model.

PURPOSE: To compare all-inside cortical-button suspensory fixation in sockets versus interference screw fixation in tunnels with respect to clinical, histologic, and biomechanical assessments of all-soft tissue (AST) tendon autografts used for anterior cruciate ligament (ACL) reconstruction in a canine model. METHODS: By use of a validated "hybrid" double-bundle ACL reconstruction technique (reconstruction of the anteromedial bundle with preservation of the native posterolateral bundle), dogs were randomly assigned to undergo either suspensory fixation in sockets (n = 6) or interference screw fixation in tunnels (n = 6). Contralateral knees were used as nonoperated controls (n = 12). Quadrupled extensor tendon autografts were used for both ACL reconstruction groups. Dogs were assessed radiographically and functionally and humanely euthanized at 12 weeks after surgery for arthroscopic, gross, biomechanical, and histologic assessments. RESULTS: Histologic assessments showed significantly (P = .018) better graft incorporation with 4-zone direct healing to bone for the grafts using suspensory fixation in sockets (16.3 ± 1.5) compared with the grafts using interference screw fixation in tunnels (14.2 ± 2.1). Furthermore, graft healing to bone was significantly better at the aperture (P = .05) and mid-socket (P = .01) location for the group that underwent suspensory fixation in sockets (16.1 ± 1.8 and 16.4 ± 1.9, respectively). CONCLUSIONS: Suspensory fixation of AST grafts in sockets was associated with superior tendon-to-bone healing compared with interference screw fixation in tunnels, with 4-zone direct graft healing to bone seen for femoral and tibial sockets only in the suspensory-fixation group. Biomechanical properties were similar between groups. CLINICAL RELEVANCE: These data provide evidence suggesting that an all-inside ACL reconstruction technique using adjustable-loop cortical-button suspensory fixation in bone sockets has potential clinical advantages for ACL reconstruction using AST grafts.

Evaluation of a Permanent Synthetic Osteochondral Implant in the Equine Medial Femoral Condyle.

OBJECTIVE: To evaluate bone ingrowth, integration, and tolerance of a synthetic osteochondral implant in the medial femoral condyle (MFC) of normal horses. STUDY DESIGN: Experimental study. ANIMALS: Adult horses (n = 6). METHODS: Horses were anesthetized and bilateral femorotibial arthrotomies were performed for placement of 1 implant consisting of polycarbonate urethane with a titanium base in 1 MFC. The contralateral MFC served as a sham-operated control without reaming of cartilage or subchondral bone. Lameness evaluations and radiographs were performed pre-operatively with subsequent monthly lameness exams and radiographs at 6 months. Synovial fluid was collected for analysis from the adjacent femoropatellar joints pre-operatively and at several intervals post-operatively. Horses were euthanatized 6 months post-operatively. Stifles were harvested for gross and histologic evaluations. RESULTS: Two horses were never lame, 2 were mildly lame, and 1 exhibited moderate lameness. Synovial fluid inflammatory parameters of the adjacent femoropatellar joints were not significantly different. No significant changes occurred radiographically over time in either stifle. Histologic assessment of synovium from the medial femorotibial joint revealed no differences in inflammatory changes between implant and sham stifles. Integration and osteoconductivity of the implant were graded as good in 4 and 3 of 5 specimens, respectively. Complications included joint sepsis resulting in euthanasia (1 horse), persistent lameness (1 horse), incisional seromas (4 horses), and incisional dehiscence (2 horses). CONCLUSION: Results of this pilot study indicate that the implant was compatible with placement in the MFC of normal horses. Implant design allowed bone ingrowth within the titanium base and provision of a synthetic articular surface.

Arrhythmogenic right ventricular cardiomyopathy in a weimaraner.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) was diagnosed postmortem in a weimaraner dog. Syncope, ventricular arrhythmias, and sudden death in this patient combined with the histopathological fatty tissue infiltration affecting the right ventricular myocardium are consistent with previous reports of ARVC in non-boxer dogs. Arrhythmogenic right ventricular cardiomyopathy has not been previously reported in weimaraners.

Cardiomyopathie ventriculaire droite arythmogène chez un Weimaraner. Une cardiomyopathie ventriculaire droite arythmogène (CVDA) a été diagnostiquée post-mortem chez un chien Weimaraner. Une syncope, des arythmies ventriculaires et une mort soudaine chez ce patient, combinées à une infiltration histopathologique par du tissu adipeux affectant le myocarde droit, correspondent à des rapports antérieurs de CVDA chez des chiens autres que des Boxers. La cardiomyopathie ventriculaire droite arythmogène n'a pas été signalée antérieurement chez des Weimaraners.(Traduit par Isabelle Vallières).

A novel system improves preservation of osteochondral allografts.

BACKGROUND: Osteochondral allografting is an option for successful treatment of large articular cartilage defects. Use of osteochondral allografting is limited by graft availability, often because of loss of chondrocyte viability during storage. QUESTIONS/PURPOSES: The purpose of this study was to compare osteochondral allografts implanted in canine knees after 28 days or 60 days of storage for (1) initial (1 week) safety and feasibility; (2) integrity and positioning with time (12 weeks and 6 months); and (3) gross, cell viability, histologic, biochemical, and biomechanical characteristics at an endpoint of 6 months. METHODS: With Institutional Animal Care and Use Committee approval, adult dogs (n=16) were implanted with 8-mm cylindrical osteochondral allografts in the lateral and medial femoral condyles of one knee. Osteochondral allografts preserved for 28 or 60 days using either the current tissue bank standard-of-care (SOC) or a novel system (The Missouri Osteochondral Allograft Preservation System, or MOPS) were used, creating four treatment groups: SOC 28-day, MOPS 28-day, SOC 60-day, and MOPS 60-day. Bacteriologic analysis of tissue culture and media were performed. Dogs were assessed by radiographs and arthroscopy at interim times and by gross, cell viability, histology, biochemistry, and biomechanical testing at the 6-month endpoint. RESULTS: With the numbers available, there was no difference in infection frequency during storage (5% for SOC and 3% for MOPS; p=0.5). No infected graft was implanted and no infections occurred in vivo. MOPS grafts had greater chondrocyte viability at Day 60 (90% versus 53%; p=0.002). For 60-day storage, MOPS grafts were as good as or better than SOC grafts with respect to all outcome measures assessed 6 months after implantation. CONCLUSIONS: Donor chondrocyte viability is important for osteochondral allograft success. MOPS allows preservation of chondrocyte viability for up to 60 days at sufficient levels to result in successful outcomes in a canine model of large femoral condylar articular defects. CLINICAL RELEVANCE: These findings provide a promising development in osteochondral allograft technology that can benefit the quantity of grafts available for use and the quality of grafts being implanted.

Intraocular and periocular lymphoma in dogs and cats: a retrospective review of 21 cases (2001-2012).

OBJECTIVE: To immunologically phenotype and histologically classify canine and feline intraocular and periocular lymphomas. METHODS: The databases of four veterinary medical diagnostic laboratories were searched to identify cases of intraocular or periocular lymphoma in dogs and cats between 2001 and 2012. Hematoxylin and eosin (H&E) stained slides were reviewed for confirmation and classification of lymphoma, and immunohistochemistry for CD3 (T-cell marker) and CD79a and/or CD20 (B-cell markers) was examined to determine the lineage of the neoplastic lymphocytes. RESULTS: Six canine and 15 feline cases of ocular lymphoma were identified. In the canine cases, there were three intraocular and three periocular lymphomas where two intraocular and one periocular lymphomas were B-cell, one of each intraocular and periocular lymphomas were T-cell and one periocular lymphoma was nonreactive with CD3, CD79a or CD20. In the feline cases, there were six intraocular and nine periocular lymphomas where five intraocular and six periocular lymphomas were B-cell, and one intraocular and three periocular lymphomas were T-cell. Only one canine case had concurrent generalized lymphadenopathy, only one canine conjunctival lymphoma had simultaneous cutaneous lymphoma, and only one feline case had bilateral ocular involvement when they were diagnosed. CONCLUSION: Canine and feline intraocular and periocular lymphomas are often of B-cell phenotype. Although in general terms lymphoma is not considered a primary tumor when it occurs in or adjacent to the globe, these tumors frequently first become evident in the globe and/or periocular area. An accurate early diagnostic approach is crucial for the patient's quality of life because B-cell lymphomas are generally more amenable to chemotherapy than T-cell lymphomas.

The histologic and biomechanical response of two commercially available small glenoid anchors for use in labral repairs.

BACKGROUND: This study examined histologic characteristics and biomechanical performance of 2 commercially available, small glenoid anchors. METHODS: Adult research dogs (n = 6) were used for histologic analysis. Anchors were inserted into the lateral rim of the glenoid using the manufacturer's protocol. The dogs were humanely euthanatized 8 weeks after anchor implantation, and the glenoids were collected for histologic analysis. Bone socket width data were compared for statistically significant (P < .05) differences. In addition, 4 matched pairs (n = 8) of human cadaveric glenoids were instrumented with 1 BioComposite SutureTak (Arthrex, Naples, FL, USA) and 1 JuggerKnot (Biomet, Warsaw, IN, USA) suture anchor in the anterior-inferior quadrant. Anchor constructs were preloaded to 5 N, cycled from 5 to 25 N for 100 cycles, and then pulled to failure. RESULTS: All JuggerKnot anchor sites were cyst-like cavities with a rim of dense lamellar bone. All BioComposite SutureTak anchor sites contained intact anchors with close approximation of anastomosing trabeculae of lamellar bone. At 8 weeks after implantation, mean socket width of the JuggerKnot anchor sites was 6.3 ± 2.5 mm, which was significantly (P = .013) larger than the mean socket width of 2.7 ± 0.7 mm measured for the BioComposite SutureTak anchor sites. The JuggerKnot anchor demonstrated larger displacements during subfailure cyclic loading (2.9 ± 1.0 mm compared with 1.3 ± 0.4 mm) and load to failure tests (13.7 ± 6.6 mm compared with 3.2 ± 0.5 mm). Statistical differences (P < .01) existed in every category except ultimate load. CONCLUSIONS: Based on the biomechanical in human bone and histologic findings in canine subjects, the all-suture anchor may be at risk for clinical failure.

Spindle cell cutaneous epitheliotropic T-cell lymphoma in an American Bulldog.

An 8-year-old American Bulldog developed coalescing exophytic bulbous nodules that grew rapidly on the left pinna and a single cutaneous mass on the left flank. Histological examination of the pinnal biopsy by a diagnostic laboratory revealed a densely cellular neoplasm with haphazardly arranged round to spindle cells with high mitotic activity and epitheliotropism. The initial diagnosis was a poorly differentiated malignant neoplasm with differential diagnoses including melanoma, tumour of histiocytic origin and, less likely, a pleomorphic lymphoma. A panel of melanoma immunohistochemical markers and immunolabelling for CD18 were pursued. Neoplastic cells were immunopositive for CD18 but negative for Melan-A, PNL2, TRP-1 and TRP-2, suggestive of a histiocytic tumour or lymphoma. The left ear masses recurred, and more masses developed on the body. The pinnectomized ear was submitted to the University of Missouri Veterinary Medical Diagnostic Laboratory. Similar cells were seen and were immunolabelled for CD18 and CD3 but were immunonegative for SOX10, CD79a and CD20. PCR for antigen receptor rearrangements revealed a clonal rearrangement of T-cell receptor gamma. These findings enabled a final diagnosis of epitheliotropic T-cell lymphoma with spindle cell morphology. Lymphoma should be considered as a potential differential diagnosis for cutaneous nodules of spindle cell morphology and lymphocytic immunohistochemical markers should be included in diagnostic panels.

Comparison of reamer irrigator aspirator (RIA) suspension versus bone marrow aspirate concentrate (BMC) for percutaneous treatment of long bone nonunions-A preclinical canine model.

OBJECTIVE: To compare the bone healing effects of percutaneously delivered bone marrow aspirate concentrate (BMC) versus reamer irrigator aspirator (RIA) suspension in a validated preclinical canine ulnar nonunion model. We hypothesized that BMC would be superior to RIA in inducing bone formation across a nonunion site after percutaneous application. The null hypothesis was that BMC and RIA would be equivalent. METHODS: A bilateral ulnar nonunion model (n= 6; 3 matched pairs) was created. Eight weeks after segmental ulnar ostectomy, RIA from the ipsilateral femur and BMC from the proximal humerus were harvested and percutaneously administered into either the left or right ulnar defect. The same volume (3 ml) of RIA suspension and BMC were applied on each side. Eight weeks after treatment, the dogs were euthanized, and the nonunions were evaluated using radiographic, biomechanical, and histologic assessments. RESULTS: All dogs survived for the intended study duration, formed radiographic nonunions 8 weeks after segmental ulnar ostectomy, and underwent the assigned percutaneous treatment. Radiographic and macroscopic assessments of bone healing at the defect sites revealed superior bridging-callous formation in BMC-treated nonunions. Histologic analyses revealed greater amount of bony bridging and callous formation in the BMC group. Biomechanical testing of the treated nonunions did not reveal any significant differences. CONCLUSION: Bone marrow aspirate concentrate (BMC) had important advantages over Reamer Irrigator Aspirator (RIA) suspension for percutaneous augmentation of bone healing in a validated preclinical canine ulnar nonunion model based on clinically relevant radiographic and histologic measures of bone formation.

Otitis interna, media, and externa with destruction of the left tympanic bulla and subluxation and septic arthritis of the left temporomandibular joint in an alpaca (Vicugna pacos).

A 1.5-year-old, 37.7 kg, female alpaca was evaluated for a 2-week history of weight loss, left ear droop, and deviation of the rostral mandible to the right. Antemortem radiography and postmortem examination revealed otitis interna, media, and externa, destruction of the left tympanic bulla, and subluxation and septic arthritis of the left temporomandibular joint.

Otite interne, moyenne et externe avec destruction de la bulle tympanique gauche et subluxation et arthrite septique de l'articulation temporomandibulaire gauche chez un alpaga(Vicugna pacos) . Une femelle alpaga âgée de 1,5 an, pesant 37,7 kg, a été évaluée pour une anamnèse de 2 semaines de perte de poids, d'oreille gauche pendante et de déviation de la mandibule rostrale à la droite. Une radiographie avant le décès et une nécropsie ont révélé une otite interne, moyenne et externe, la destruction de la bulle tympanique gauche ainsi qu'une subluxation et l'arthrite septique de l'articulation temporomandibulaire gauche.(Traduit par Isabelle Vallières).

Making the Case for Hyperosmolar Saline Arthroscopic Irrigation Fluids: A Systematic Review of Basic Science, Translational, and Clinical Evidence.

Commonly used isotonic arthroscopic irrigation fluids, such as normal saline or lactated Ringer's, were initially formulated for intravenous administration so they do not replicate the physiologic properties of healthy synovial fluid. Synovial fluid plays an important role in regulating joint homeostasis such that even transient disruptions in its composition and physiology can be detrimental. Previous studies suggest that hyperosmolar solutions may be a promising alternative to traditional isotonic fluids. This manuscript sought to systematically review and synthesize previously published basic science, translational, and clinical studies on the use of hyperosmolar arthroscopic irrigation fluids to delineate the optimal fluid for clinical use. A systematic literature search of MEDLINE/PubMed and Embase databases was performed in accordance with Preferred Reporting Items for Systemic Reviews and Meta-analyses (PRISMA) guidelines. The search phrases were: ("cartilage" AND "hyperosmolar"); ("arthroscopy" OR "arthroscopic" AND "hyperosmolar"). The titles, abstracts, and full texts were screened for studies on hyperosmolar solutions and articular cartilage. Study quality was assessed, and relevant data were collected. A meta-analysis was not performed due to study heterogeneity. A risk of bias assessment was performed on the included translational and clinical studies. There were 10 basic science studies, 2 studies performed in translational animal models, and 2 clinical studies included in this review. Of the basic science studies, 7 utilized a mechanical injury model. The translational studies were carried out in the canine shoulder and equine stifle (knee) joint. Clinical studies were performed in the shoulder and knee. Multiple basic science, translational, and clinical studies highlight the short-term safety, cost-effectiveness, and potential benefits associated with use of hyperosmolar solutions for arthroscopic irrigation. Further work is needed to develop and validate the ideal formulation for a hyperosmolar irrigation solution with proven long-term benefits for patients undergoing arthroscopic surgeries.

Comparison of a novel bone-tendon allograft with a human dermis-derived patch for repair of chronic large rotator cuff tears using a canine model.

PURPOSE: This study tested a bone-tendon allograft versus human dermis patch for reconstructing chronic rotator cuff repair by use of a canine model. METHODS: Mature research dogs (N = 15) were used. Radiopaque wire was placed in the infraspinatus tendon (IST) before its transection. Three weeks later, radiographs showed IST retraction. Each dog then underwent 1 IST treatment: debridement (D), direct repair of IST to bone with a suture bridge and human dermis patch augmentation (GJ), or bone-tendon allograft (BT) reconstruction. Outcome measures included lameness grading, radiographs, and ultrasonographic assessment. Dogs were killed 6 months after surgery and both shoulders assessed biomechanically and histologically. RESULTS: BT dogs were significantly (P = .01) less lame than the other groups. BT dogs had superior bone-tendon, tendon, and tendon-muscle integrity compared with D and GJ dogs. Biomechanical testing showed that the D group had significantly (P = .05) more elongation than the other groups whereas BT had stiffness and elongation characteristics that most closely matched normal controls. Radiographically, D and GJ dogs showed significantly more retraction than BT dogs (P = .003 and P = .045, respectively) Histologically, GJ dogs had lymphoplasmacytic infiltrates, tendon degeneration and hypocellularity, and poor tendon-bone integration. BT dogs showed complete incorporation of allograft bone into host bone, normal bone-tendon junctions, and well-integrated allograft tendon. CONCLUSIONS: The bone-tendon allograft technique re-establishes a functional IST bone-tendon-muscle unit and maintains integrity of repair in this model. CLINICAL RELEVANCE: Clinical trials using this bone-tendon allograft technique are warranted.

Alveolar echinococcosis in a dog in Missouri, USA.

A 10-y-old, castrated male Boxer dog that was born and had lived in Missouri without any travel history to other states, except for a few trips to Kansas, was presented with a distended abdomen and declined health. Ultrasonographic examination revealed a large hepatic mass, and the dog was euthanized. A postmortem examination revealed that the left liver lobes were largely replaced by a white-to-tan multilobular mass with a cobblestone surface. The lesion also involved the diaphragm. Histologically, hepatic architecture was effaced by large areas of necrosis with numerous, ≤0.2-cm, cystic structures that stained positively with periodic acid-Schiff stain and contained calcareous corpuscles. Gross and microscopic hepatic lesions were compatible with alveolar echinococcosis (AE) caused by Echinococcus multilocularis. PCR examination confirmed E. multilocularis, and results from genotyping were consistent with the E4 haplotype. To our knowledge, this is only the second canine AE case and the third pet dog that has been confirmed to be infected by E. multilocularis in the contiguous United States. E. multilocularis is a serious health risk for both pet dogs and humans.