Combined Gap and Interpositional Arthroplasty Utilizing Three-Dimensional Printed Model in a Dog with Temporomandibular Joint Ankylosis and Pseudoankylosis.

Objective: To report the surgical treatment of a canine with both ankylosis and pseudoankylosis of temporomandibular joint (TMJ). Methods: The patient presented for inability to open his mouth. Facial asymmetry with normal dental occlusion was appreciated and computed tomography (CT) was performed. CT was used to diagnose ankylsosis and pseudoankylosis of left TMJ secondary to chronic maxillofacial trauma. A gap arthroplasty followed by interpositional arthroplasty using temporalis muscle fascia was performed to remove the site of fusion and prevent re-ankylosis between remaining cut boney surfaces. A three-dimensional (3D) printed skull for surgical planning and intraoperative spatial localization was employed. Results: Following preoperative and intraoperative evaluation of the 3D printed skull, the surgery was performed successfully without major complications. The patient's TMJ range of motion was markedly improved and remains improved as noted by inter-incisal distance measurements, ability to pant, and ease of chewing. Conclusion: A combined Gap and interpositional arthroplasty was assisted with the use of a 3D printed skull and immediately resulted in improved TMJ range of motion and patient quality of life. Three-month postoperative CT revealed stable ostectomies with no complications, with the exception of left-sided disuse masticatory muscle atrophy. Long-term follow-up is warranted. Clinical Significance: Three-dimensional printed skull models may be utilized preoperatively and intraoperatively to determine individual variants and landmarks, especially in cases where anatomical structures are difficult to recognize. Gap arthroplasty with interpositional myofascial transposition is an option for a patient with both anklyosis and pseudoankylosis of the TMJ.

Articulated Joint Distraction in a Cadaveric Model of the Canine Elbow.

OBJECTIVE: The aim of this study was to determine if articulated joint distraction in the canine elbow can effectively maintain a distraction gap between the articular surfaces of the canine elbow under a weight-bearing load. STUDY DESIGN: An articulated external skeletal fixator with turnbuckles was applied to seven canine cadaveric elbow specimens. Specimens were potted and mechanically tested at 135° of flexion, while joint contact pressure was recorded at three locations within the elbow. Joint distraction was sequentially increased, and loads of 5 N, 90 N and 180 N were incrementally applied. This process was repeated until no pressure was recorded at each of the three locations within the elbow under 180 N of applied load. RESULTS: To achieve 0 N of joint contact force with 180 N of axial load, the average amount of distraction needed was 2.3 ± 0.71 mm (range, 1.8-3.6 mm) at the distal turnbuckles and 1.67 ± 1.10 mm (range, 1.8-2.7 mm) at the proximal turnbuckles. CONCLUSION: Results suggest that joint distraction can effectively decrease articular pressure within the canine elbow joint. A maximum of 3.6 mm of distraction between the fixator turnbuckles was necessary to eliminate joint contact for the construct tested. Clinical investigation is necessary to establish if articulated elbow joint distraction is a safe and effective for the treatment of canine elbow osteoarthritis.

Short- and long-term outcomes after shoulder excision arthroplasty in 7 small breed dogs.

This study reports short- and long-term clinical outcomes following excision arthroplasty in 7 small breed dogs with shoulder pathology. Lameness and pain were scored before surgery, and reassessed at short- and long-term follow-ups with measurements of range of motion (ROM), scapulo-humeral angles of extension (EA) and flexion (FA), and muscle girth (MG) of the operated and contralateral limbs. All dogs improved clinically for lameness and pain. Range of motion, EA, and FA of the operated limb were not significantly different compared with the contralateral limb at short-term follow-up, but ROM and EA were significantly decreased at long-term examination. Muscle girth was not significantly different than the contralateral limb. Radiographic re-evaluations showed bony proliferation around osteotomies without interosseous union in most dogs and all owners were satisfied with the surgery outcome. Excision arthroplasty seems to be an effective treatment for chronic shoulder pathologies in small dogs. Range of motion and EA were decreased and a mild lameness remained present at long-term follow-up.

Évolution à court et à long terme suite à une arthroplastie d'épaule chez sept chiens de petite race. Cette étude rapporte l'évolution clinique à court et long terme suite à une arthroplastie d'excision chez sept chiens de petite race avec des anomalies de l'épaule. Les degrés de boiterie et de douleur ont été évalués avant la chirurgie et réévalués à court et à long terme avec l'amplitude de mouvement (ADM), les angles d'extension (AE) et de flexion (AF) de l'épaule, et le périmètre musculaire (PM) du membre opéré et du membre controlatéral. Tous les chiens se sont améliorés cliniquement concernant la boiterie et la douleur. Il n'y avait pas de différence significative entre l'ADM, AE et AF du membre opéré par rapport au membre controlatéral à court terme, par contre l'ADM et l'AE étaient significativement réduits à long terme. Le PM n'a pas changé de façon significative comparativement au membre controlatéral. Les réévaluations radiographiques ont montré une prolifération osseuse le long des traits d'ostéotomie sans évidence d'union interosseuse sur la majorité des chiens et tous les propriétaires ont été satisfaits du résultat de la chirurgie. L'arthroplastie d'excision semble être un traitement efficace des pathologies chroniques de l'épaule chez les petits chiens. Une diminution de l'ADM et l'AE et une légère boiterie restaient présents à long terme.(Traduit par les auteurs).

Avaliação radiográfica e tomográfica de cães submetidos à artroplastia coxofemoral total híbrida / Radiographic and tomographic evaluation of total hybrid hip replacement in dogs

A artroplastia total da articulação coxofemoral é a técnica cirúrgica mais efetiva para o tratamento da displasia coxofemoral canina grave. Na atualidade, o exame radiográfico é o método mais utilizado para se avaliar esse procedimento em cães, porém possui algumas limitações. Já o exame tomográfico por meio de tomografia computadorizada possibilita a aquisição de imagens sem sobreposições e, dessa forma, a determinação do posicionamento dos componentes protéticos com maior precisão. A presente pesquisa teve como objetivo avaliar, por meio de exames radiográficos e tomográficos, a utilização de uma prótese total modular híbrida da articulação coxofemoral desenvolvida e confeccionada no Brasil, aplicada experimentalmente em cães sadios. Foram utilizados seis cães esqueleticamente maduros, previamente submetidos ao procedimento cirúrgico da articulação coxofemoral esquerda. Os cães foram submetidos ao exame tomográfico aos 360 dias e três anos após a cirurgia. Todos os animais apresentaram bom posicionamento dos componentes protéticos e redução articular adequada. Ao exame tomográfico, entretanto, foram detectadas áreas de preenchimento irregular em alguns animais. Adicionalmente, o exame tomográfico permitiu a detecção e monitoração de áreas de reabsorção óssea ao redor do componente acetabular. Assim, o exame tomográfico mostrou-se útil na avaliação das articulações protéticas, com a vantagem de apresentar ótima definição das imagens e permitir quantificar alterações periprotéticas e mensurar relações articulares, fundamentais para o acompanhamento pós-cirúrgico tardio.(AU)

The total hip arthroplasty is the most effective surgical technique for the treatment of severe canine hip dysplasia. Currently, the radiographic examination is the most common method used to assess this procedure in dogs, but has some limitations. CT scan by computed tomography instead enables the acquisition of images without overlap, thereby determining the positioning of prosthetic components with greater accuracy. This research aimed to evaluate by radiography and CT scan examinations the use of a hybrid modular total hip prosthesis developed and made in Brazil, applied experimentally in healthy dogs. Six skeletally mature dogs, which previously underwent surgery on the left hip joint were used. The dogs underwent CT scan at 360 days and three years after surgery. All animals showed good positioning of prosthetic components, and proper joint reduction. In the CT scan, however, it was possible to detect irregular fill areas in some animals. In addition, CT scan allowed the detection and monitoring of areas of bone resorption around the acetabular component. Therefore, the CT scan was useful in the evaluation of prosthetic joints, with the advantage of optimum sharpness of the images and allowing for the possibility of quantifying peri-prosthetic changes and measure joint, fundamental relations for late postoperative follow-up.(AU)

Radiographic, Surgeon and Owner Assessment of the BioMedtrix TATE(®) Elbow Arthroplasty.

OBJECTIVE: To report the long-term radiographic and clinical outcome of the BioMedtrix TATE elbow arthroplasty system in dogs. Assessment was via radiographs, a surgeon-based questionnaire, and owner assessment of outcome using the Liverpool osteoarthritis in dogs (LOAD) and canine brief pain inventory (CBPI) questionnaires. STUDY DESIGN: Retrospective multicenter, case series. ANIMALS: Client-owned dogs undergoing TATE elbow arthroplasty. METHODS: Questionnaires were distributed to surgeons in the United Kingdom performing TATE elbow arthroplasty and to the owners of the dogs operated on. Owners completed the LOAD and CBPI questionnaires. All completed questionnaires from surgeons and owners, and radiographs of the dogs were collated and analyzed. RESULTS: Surgeon questionnaires and radiographs were obtained for 33 elbows from 32 dogs, with owner questionnaires obtained for 19 dogs. Perioperative, short-term, and mid-term complication rates were 60%, 15%, and 15%, respectively. Radiographic assessment of component alignment showed 62% of cartridges were valgus or varus malaligned and 56% of cartridges were either translated medially or laterally relative to the long axis of the ulnar. There was no significant association between component alignment and final clinical outcome. Surgeon assessment reported 24% of dogs to have full, 52% acceptable, and 24% unacceptable outcome. Owner assessment showed significant decreases in pain severity and pain interference from preoperative to final status but no change in mobility scores. CONCLUSIONS: A high complication rate and variability in component placement was recorded with TATE athroplasty. However, component malalignment did not negatively impact clinical outcome. Final clinical outcome was favorable for most cases with significant reductions in pain severity and interference scores despite no changes in mobility scores.

Comparison of bupivacaine and dexmedetomidine femoral and sciatic nerve blocks with bupivacaine and buprenorphine epidural injection for stifle arthroplasty in dogs.

OBJECTIVE: To compare the quality of anesthesia and analgesia from femoral and sciatic nerve blocks (FS) with bupivacaine and dexmedetomidine with that from an epidural injection (EPI) with bupivacaine and buprenorphine in dogs undergoing unilateral stifle arthroplasty. STUDY DESIGN: Prospective, blinded, randomized, clinical comparison. ANIMALS: Twenty-six dogs weighing 36 ± 10 kg and aged 5 (1-11) years. METHODS: Dogs were randomly assigned to either FS [n = 13; bupivacaine 0.5% (0.5 mg kg(-1) ) plus dexmedetomidine (0.1 µg kg(-1) ) for each nerve] or EPI [n = 13; bupivacaine 0.5% (1 mg kg(-1) ) plus buprenorphine (4 µg kg(-1) )]. Data collected included intraoperative cardiopulmonary variables and postoperative pain scores (Glasgow Composite Pain Scale), sedation scores, opioid consumption, time to urination and time to return of various behaviors. Rescue analgesia (hydromorphone 0.05 mg kg(-1) ) was administered intravenously whenever pain scores were ≥ 6/24. Subsequent data from rescued dogs were excluded from further analysis. RESULTS: No differences were found for any of the variables evaluated during and after anesthesia. Over 60% (nine dogs in FS, eight dogs in EPI) of patients from either group did not need additional analgesia within the 24 hour observational period. Three and four patients in FS and EPI, respectively, that required rescue analgesia did so within the first 30 minutes after extubation; only one patient in EPI required supplemental analgesia more than 4 hours after extubation. One patient in each group did not urinate spontaneously for 24 hours. CONCLUSIONS AND CLINICAL RELEVANCE: Both techniques have the potential to provide sufficient analgesia for up to 24 hours in approximately two-thirds of dogs. Careful observation for signs of pain and preparedness to intervene is still recommended. The incidence of urinary retention was low in both groups. These techniques show promise for providing high-quality analgesia for stifle arthroplasty.

Clinical outcomes associated with the initial use of the Canine Unicompartmental Elbow (CUE) Arthroplasty System(®).

We evaluated mid- to long-term outcomes with respect to function and complications in dogs undergoing canine unicompartmental elbow (CUE) arthroplasty for treatment of medial compartment disease of the elbow. This prospective multicenter case series is the first group of clinical cases to receive CUE arthroplasty. Cases (each elbow that underwent CUE performed by a participating surgeon) were enrolled into an electronic database and prospectively followed to determine and record all associated complications, as well as functional outcomes. There were 103 cases from 18 surgeons. Final follow-up time ranged from 6 to 47 mo with a mean and median of 10 mo. Canine unicompartmental elbow was associated with 1 catastrophic (1%), 11 major (10.7%), and 28 minor (27.2%) complications. Outcomes following CUE were reported as full function in 49 cases (47.6%), acceptable function in 45 cases (43.7%), and unacceptable function in 9 cases (8.7%). We conclude that CUE arthroplasty is an appropriate consideration for treatment of medial compartment disease of the elbow in dogs.

Résultats cliniques associés à l'utilisation initiale du système d'arthroplastieCanine Unicompartmental Elbow (CUE) Arthroplasty SystemMD. Nous avons évalué les résultats à long et à moyen terme relativement à la fonction et aux complications chez les chiens subissant une arthroplastie du coude unicompartimental canin (CUC) pour le traitement de la maladie compartimentale médiale du coude. Cette série prospective de cas multicentres représente le premier groupe de cas cliniques à recevoir une arthroplastie CUC. Les cas (chaque coude qui a subi une CUC réalisée par un chirurgien participant) étaient inscrits dans une base de données électroniques et suivis de manière prospective afin de déterminer et de consigner toutes les complications connexes ainsi que les résultats fonctionnels. Il y avait 103 cas provenant de 18 chirurgiens. Le temps de suivi final s'échelonnait de 6 à 47 mois avec une moyenne et une médiane de 10 mois. Le coude compartimental canin a été associé à 1 complication catastrophique (1 %), à 11 complications majeures (10,7 %) et à 28 complications mineures (27,2 %). Les résultats après l'arthroplastie CUC ont été signalés comme une fonction complète dans 49 cas (47,6 %), une fonction acceptable dans 45 cas (43,7 %) et une fonction inacceptable dans 9 cas (8,7 %). Nous avons conclu que l'arthroplastie CUC est une considération appropriée pour le traitement de la maladie compartimentale médiale du coude chez les chiens.(Traduit par Isabelle Vallières).

In vitro biomechanical comparison of load to failure testing of a canine unconstrained medial compartment elbow arthroplasty system and normal canine thoracic limbs.

Elbow dysplasia, primarily affecting the medial compartment, is the most common cause of lameness in the thoracic limb. Elbow arthroplasty is an option for end stage or severely affected patients. The purpose of this study was to compare ex vivo axial load to failure of an implanted novel elbow arthroplasty system to control limbs. The partial arthroplasty is a medial compartmental, unconstrained system, intended to allow conversion to total arthroplasty. We hypothesized that there would not be any significant difference between implanted and controlled limbs when loaded to failure. Six pairs of medium mixed breed canine cadaveric thoracic limbs were prepared for comparison of failure loading of control and implanted limbs. Axial compression was performed using a mechanical testing system. Failure loads were normalized to bodyweight. The mean normalized failure load (N/kg) for the implanted limbs and control limbs were 2.47 (range: 1.62-3.38) and 2.68 (range: 2.25-3.25), respectively. An implanted to control ratio of 0.93 ± 0.19 was calculated. The difference between paired control and implanted limbs in normalized failure loading was not significant (p = 0.38). There were not any differences noted in the yield load (p = 0.30), stiffness (p = 0.62), or energy (0.58). Failure modes were recorded. We concluded that the differences between implanted and control limbs in supra-physiologic axial load to failure were not significant.

Femoral head and neck excision arthroplasty in a leopard tortoise (Stigmochelys pardalis).

Cases of femoral head and neck excision arthroplasty are infrequently reported in reptiles, and details of surgical technique and clinical outcome in chelonia are lacking. An adult female leopard tortoise (Stigmochelys pardalis) was presented with chronic non-weight-bearing lameness of the left hind limb. Examination and radiography were consistent with coxofemoral luxation, and as a result of the chronic presentation, surgical intervention was recommended. A cranial approach to the joint via the prefemoral fossa afforded good surgical exposure. A depressed lytic acetabular lesion was noted during the procedure, postulated to be a result of abnormal wear from the luxated femoral head. A fiberglass prop was used during recovery to allow extension of the limb without full weight-bearing. Lameness persisted postoperatively, but limb usage significantly improved.

Cervical arthroplasty in two dogs with disk-associated cervical spondylomyelopathy.

CASE DESCRIPTION: A 4-year-old sexually intact male Doberman Pinscher (dog 1) was evaluated for signs of recurrent cervical pain and ataxia, and a 12-year-old neutered male mixed-breed dog (dog 2) was evaluated for a 4-month history of ataxia and tetraparesis. CLINICAL FINDINGS: Examination via magnetic resonance imaging (MRI) revealed spinal cord compression due to disk-associated cervical spondylomyelopathy at C6-7 in dog 1 and at C5-6 in dog 2. TREATMENT AND OUTCOME: Both dogs were surgically treated with a ventral slot procedure and spinal cord decompression, followed by insertion of a titanium cervical disk prosthesis at the affected site. Evaluation of radiographs obtained immediately after surgery indicated that each prosthesis was appropriately placed and provided adequate distraction. Radiographic and neurologic evaluations were performed 2 weeks and 3, 6, and 12 months after surgery in both dogs and 18 months after surgery in dog 1. Distraction of the vertebral bodies decreased moderately over time in both dogs. Intervertebral mobility determined via radiographic assessment of the prosthetic disk during neutral positioning, flexion, and traction of the cervical vertebral column was lost over time in dog 1 and was not achieved in dog 2. Eighteen months after surgery, results of MRI in dog 1 indicated adequate spinal cord decompression with no degeneration in other cervical disks. CLINICAL RELEVANCE: Cervical arthroplasty was well tolerated with no complications, and outcome was excellent in both dogs; prosthesis presence did not affect ability to reassess the area via MRI. Studies of cervical arthroplasty in dogs with disk-associated cervical spondylomyelopathy are warranted.

Successful management of simple fractures of the femoral neck with femoral head and neck excision arthroplasty in two free-living avian species.

A red-tailed hawk (Buteo jamaicensis) and a Canada goose (Branta canadensis) were evaluated for unilateral pelvic limb lameness. Physical examination findings and results of diagnostic imaging revealed femoral neck fractures in both birds. Both birds were treated with a femoral head and neck excision arthroplasty. The affected legs were not immobilized, and the birds were encouraged to use the legs immediately after surgery to encourage formation of a pseudoarthrosis. Within 2 weeks, both birds were using the affected limb well enough to be either successfully released or transferred to a wildlife rehabilitation facility. Femoral head and neck excision arthroplasty without immobilization of the limb is recommended for managing avian femoral neck fractures, especially in free-ranging species in which a rapid and complete or near complete return to function is vital for survival in the wild.

Artroplastia total coxofemoral em cães: estudo experimental com prótese nacional / Total hip arthroplasty in dogs: experimental study using a prosthesis made in Brazil

A prótese total da articulação coxofemoral representa uma das técnicas mais aceitas, nos Estados Unidos e na Europa, para o tratamento cirúrgico da displasia coxofemoral severa em cães. Entretanto, ainda é pouco difundida e estudada no Brasil. No presente trabalho, foi utilizada prótese confeccionada no Brasil, com o objetivo de avaliar a sua aplicação, evolução pós-operatória e complicações associadas. Foram utilizados dez cães, sadios e adultos. Todos foram submetidos ao procedimento de prótese total cimentada da articulação esquerda utilizando-se um componente femoral de cromo-cobalto, cabeça fixa, e uma cúpula acetabular de polietileno de alta densidade. As avaliações clínicas e radiográficas foram realizadas no pré-operatório e aos 30, 60, 90, 120 e 150 dias após a intervenção cirúrgica. A prótese total utilizada proporcionou um bom resultado funcional ao membro operado, em 80 por cento dos animais. As principais complicações relacionadas foram a luxação protética e a soltura do componente acetabular.

Total hip prosthesis is one of the most accepted methods used in the United States and Europe for the treatment of severe hip dysplasia in dogs. However, there are few studies with the technique and the procedure is still not well established in Brazil. A prosthesis made in Brazil was used. The purpose of this study was to evaluate its application and determine the postoperative finds and complications. Ten mature healthy dogs were used. A fixed-head cemented total hip prosthesis was applied on the left leg of the dogs. A chrome-cobalt femoral stem and high density polyetylene acetabular cup was used. Clinical and radiographic evaluations were performed before surgery and again at 30, 60, 90, 120 e 150 days post operation. Proper weight bearing was noticed on the operated limb in the majority of the dogs. The main complications were the dislocation and loosening of the acetabular cup.

In vitro biomechanical comparison of cervical disk arthroplasty, ventral slot procedure, and smooth pins with polymethylmethacrylate fixation at treated and adjacent canine cervical motion units.

OBJECTIVE: To compare the biomechanical properties of cervical arthroplasty to a ventral slot procedure and pin-polymethylmethacrylate (pin-PMMA) fixation. SAMPLE POPULATION: Fresh cadaveric cervical (C2-T1) spines from 6 large dogs. METHODS: Four spinal conditions were studied in each spinal specimen: intact, disk arthroplasty, ventral slot, and fixation with smooth pin-PMMA at C5-C6 intervertebral space. Axial compression, torsion, flexion-extension, and lateral bending moments were sequentially tested on each specimen for the 4 spinal conditions. Data from the C3-C4, C4-C5, C5-C6, and C6-C7 vertebral motion units (VMUs) were compared among treatments. RESULTS: In axial compression and torsion, the ventral slot procedure allowed significantly less motion than intact, pin-PMMA, and arthroplasty groups at C5-C6. In lateral bending and flexion-extension, pin-PMMA had the least motion of C5-C6, followed by the arthroplasty group, intact spine, and ventral slot, all of which were significantly different from each other. Overall, the artificial disk was better able to mimic the behavior of the intact specimens compared with the ventral slot and pin-PMMA, producing similar displacements in axial compression and rotation in torsion, but more limited motion than intact in flexion-extension and in lateral bending. CONCLUSION: Cervical spine specimens with an implanted prosthesis have biomechanical behaviors more similar to an intact spine compared with spinal specimens with ventral slot and pin-PMMA procedures. Cervical arthroplasty may then preserve some of the motion in the affected area after neural decompression while providing distraction. CLINICAL RELEVANCE: Cervical arthroplasty should be further investigated in vivo to determine if it is a viable alternative to the ventral slot or pin-PMMA procedures for surgical treatment of cervical diseases in dogs and in particular for treatment of disk-associated caudal cervical spondylomyelopathy.

In vitro elution studies of amikacin and cefazolin from polymethylmethacrylate.

OBJECTIVE: To compare the in vitro elution characteristics of amikacin and cefazolin from polymethylmethacrylate (PMMA) alone and in combination. STUDY DESIGN: A prospective, controlled, experimental study. METHODS: Three aliquots of 6 g sterile PMMA were measured and to them added (1) 750 mg amikacin; (2) 1050 mg cefazolin; and (3) 750 mg amikacin and 1050 mg cefazolin. Ten beads of each antimicrobial/PMMA combination were placed in 5 mL phosphate-buffered saline (PBS) at pH 7.4 and room temperature with constant agitation. PBS was sampled at 15 time points between 1 hour and 30 days. Amikacin concentrations were determined by fluorescence polarization immunoassay and cefazolin concentrations by high-performance liquid chromatography. RESULTS: Amikacin and cefazolin eluted at concentrations greater than 8 and 4 times, respectively, above the minimum inhibitory concentration (MIC) for susceptible bacteria over 30 days. Co-elution of the antibiotics resulted in a greater rate and proportion of antibiotic eluted. Concentrations of amikacin and cefazolin in the co-eluted fluid were not maintained sufficiently above the MIC for selected bacteria over 30 days. CONCLUSIONS: PMMA beads of only amikacin or cefazolin-eluted concentrations greater than the MIC for selected bacteria for 30 days. Co-elution of the antibiotics at the selected doses resulted in a significantly shorter duration of elution and may not be effective for treatment of wound infection. CLINICAL RELEVANCE: Co-elution of amikacin and cefazolin from PMMA at the selected doses cannot be recommended for sustained treatment of infection.

Artroplastia excisional pelo acesso dorsal-caudal em 16 cães com necrose asséptica na cabeça do fêmur / The excisional arthroplasty through the dorsocaudal access of 16 dogs with aseptic necrosis of the femoral head / Arthoplastía escisional por acceso dorso-caudalen 16 perros con necrosis aséptica de la cabeza femoral

O trabalho teve como objetivo, descrever a técnica da artroplastia excisional pelo acesso dorso-caudal em 16 cães com necrose asséptica da cabeça do fêmur, como uma nova alternativa terapêutica cirúrgica para o alívio do paciente traumatizado. A necrose asséptica da cabeça femoral, também conhecida como Legg-Calvé-Perthes, apresenta em todos os casos, o osso da cabeça e colo femorais com necrose e deformação. Acomete normalmente animais de pequeno porte, apresentando ao exame clínico claudicação gradual do membro afetado, devido à dor articular. Ao exame radiográfico observam-se focos de diminuição da densidade óssea na cabeça e colo femorais, e em casos mais graves presença de osteófitos na margem acetabular dorsal. Foram atendidos 16 cães (7 Poodle; 4 Pinscher; 1 Pequinês; 1 Beagle; 1 Yorkshire Terrier; 2 Sem Raça Definida) no Hospital Veterinário da Universidade Norte do Paraná (UNOPAR), Arapongas, PR, com diagnóstico de necrose asséptica da cabeça do fêmur. O tratamento preconizado foi cirúrgico, através da artroplastia por excisão da cabeça e colo femorais com abordagem dorso-caudal, e o pós-operatório constituíram-se de antibioticoterapia por 3 dias, curativo tópico até a cicatrização da ferida cirúrgica. A administração de DMSO (Dimesol®) na dose de 0,8 mL/Kg diluído em 125 mL de solução fisiológica de NaCl a 0,9%, durante 4 dias, repouso nos primeiros 7 dias e volta gradativa ao exercício. O retorno ao uso do membro afetado e o desaparecimento total da claudicação foram observados 20 dias após a cirurgia.

The aim of this study is to describe the excisional arthroplasty technique through dorsocaudal access in 16 dogs with aseptic necrosis of the femoral head as a new therapeutic alternative for the relief of traumatized patients. The femoral head necrosis, also known as Legg-Calvé-Perthes, presents, in all cases, both the bone of the femoral head and the neck with necrosis and deformation. Small animals are usually affected thus presenting a gradual level of lameness upon the painful member due to joint pain in the clinical exam. Traits of bone density loss in the femoral head and neck, and, in severe cases, the occurrence of osteophyte in the dorsal border of acetabular appear in the radiographical exam. Sixteen dogs (7 Poodle; 4 Pinscher; 1 Pekinese; 1 Beagle; 1 Yorkshire Terrier; 2 mongrel dogs) presenting aseptic necrosis of the femoral head were assisted in the Veterinary Hospital of the Universidade do Norte do Paraná (UNOPAR) in Arapongas–PR . The surgery was carried out through the excision arthroplasty of the head and femoral neck with a dorsocaudal approach. The postoperative period consisted of antibioticotherapy for 3 days, topical curative until the surgical wound healing. The administration of 0,8 ml/kg DMSO (Dimesol®) diluted into 125 ml of NaCL 0.9% physiological solution for 4 days; a rest cure in the first 7 days followed by a gradual return to the exercise. Returning to use the affected member as well as the total disappearance of the lameness level was observed 20 days after the surgery.

El trabajo tuvo como objetivo, describir la técnica de la artroplastía por escisión dorsal en 16 perros con necrosis aséptica de la cabeza femoral como una nueva alternativa terapéutica de la cirugía para el alivio del paciente traumatizado. La necrosis aséptica de la cabeza femoral, también conocida como Legg-Calvé-Perthes, presenta en todos los casos, el hueso de la cabeza y cuello femoral con necrosis y deformaciones. Acomete normalmente a los animales de pequeño porte, presentando en el examen clínico claudicación gradual del miembro afectado, debido al dolor articular. En el examen radiográfico se observa focos de disminución de la densidad ósea en la cabeza y en el cuello femoral, y en los casos más graves, la presencia de osteófitos en la borda del acetábulo dorsal. Fueron atendidos 16 perros [7 Poodles, 4 pinscher, 1 pequinés, 1 Beagle, 1 Yorkshire Terrier, 2 Sin Raza Definida (SRD)] en el Hospital Veterinario de la Universidad Norte del Paraná (UNOPAR) - Arapongas-PR con diagnóstico de necrosis aséptica de la cabeza femoral. El tratamiento proconizado fue la cirugía a através de la artroplastía por escisión de la cabeza y el cuello femoral con abordaje dorso-caudal y el posoperatorio se constituyó de antibiótico terapia por 3 (tres) días, curativo tópico hasta la cicatrización de la herida quirúrgica, administración de DMSO (Dimesol®) en la dosis de 0,8 ml/kg diluído en 125 ml de solución fisiológica de NaCL a 0.9% por 4 (cuatro) días, reposo en los primeros 7 (siete) días y vuelta gradual a los ejercicios. El retorno al uso del miembro afectado y el desaparecimiento total de la claudicación fue observado 20 (veinte) días después de la cirugía.

Mapping of donor and recipient site properties for osteochondral graft reconstruction of subchondral cystic lesions in the equine stifle joint.

REASONS FOR PERFORMING STUDY: To improve osteochondral graft reconstruction of subchondral cystic lesions in the medial and lateral femoral condyles by matching the material properties of donor and recipient sites. OBJECTIVES: To measure biomechanical and biochemical parameters that influence the function and healing of osteochondral grafts used to reconstruct subchondral cystic lesions. HYPOTHESIS: Suitable donor sites are available within the stifle joint for reconstructing the femoral condyles, despite considerable regional property variation. METHODS: Fifty-six osteochondral cores were harvested from 6 distal femurs for initial studies that determined subchondral bone modulus of elasticity and ultimate stress. In a second study, 28 osteochondral cores were harvested from 6 distal femurs to measure cartilage aggregate modulus, thickness and sulphated glycosaminoglycan (sGAG) content. Using micro-CT imaging, subchondral bone mineral density and bone volume fraction were also measured. In both studies 2-dimensional contour plots using a bicubic interpolation method and normalised data were generated to allow visual comparison of joint surface characteristics. Statistical comparisons between donor and recipient site raw data were made using an ANOVA for repeated measures with a post hoc Tukey test. RESULTS: Material properties of cartilage and bone vary considerably over the surface of the stifle joint but the central region of the medial condyle, where subchondral cystic lesions freqdently occur, typically demonstrated bone strength and modulus values of the highest observed. Cartilage thickness and aggregate modulus were highest in the medial femoral condyle and axial aspect of the lateral condyle. CONCLUSIONS: Material properties of the grafts from the trochlear groove and axial aspect of the lateral trochlear ridge were the closest match for those found in the medial condyle, whereas properties of the lateral condyle were most similar to those found in the trochlear groove and axial aspect of the medial trochlear ridge.

Autologous osteochondral grafting (mosaic arthroplasty) for treatment of subchondral cystic lesions in the equine stifle and fetlock joints.

OBJECTIVE: To describe treatment of equine subchondral bone cysts (SBCs) by reconstruction of the articular surface with osteochondral grafts. STUDY DESIGN: Case series of horses with SBCs unresponsive to conservative therapy. ANIMALS: Eleven horses (1-12 years). METHODS: SBCs were identified in 4 locations: medial femoral condyle (5 horses), lateral femoral condyle (1), distal epiphysis of the metacarpus (4), or metatarsus (1). Osteochondral autograft transplantation (mosaic arthroplasty) was performed, taking grafts from the abaxial border of the medial femoral trochlea of the unaffected limb. Graft implantation was achieved through a small arthrotomy or by arthroscopy depending on SBC location. RESULTS: All horses improved postoperatively; 10 horses had successful outcomes with radiographic evidence of successful graft incorporation and 7 returned to a previous or higher activity level. On follow-up arthroscopy (5 horses) there was successful reconstitution of a functional gliding surface. One horse had delayed incorporation of a graft because of a technical error but became sound. One horse had recurrence after 4 years of work and soundness. One stallion was used for breeding and light riding because of medial meniscal injuries on the same limb. CONCLUSIONS: Implantation of osteochondral grafts should be considered for SBC when conservative management has not improved lameness and there is a risk of further joint injury and degeneration. CLINICAL RELEVANCE: Mosaic arthroplasty should be considered for treatment of subchondral bone cysts of the femoral condyle and distal articular surface of the metacarpus/tarsus in horses that are refractory to non-surgical management.

Arthroscopic mosaic arthroplasty in the equine third carpal bone.

OBJECTIVE: To investigate survival and function of autogenous heterotopic osteochondral grafts in a site where injuries are common. STUDY DESIGN: Three osteochondral grafts were harvested arthroscopically from the femoropatellar joint and transplanted to the third carpal bone (C(3)). Nine months later, histologic, histomorphometric, and biochemical comparisons were made between the transplanted grafts in C(3) and tissue adjacent to the recipient site, the opposing radial carpal bone (C(r)), the donor site in the femoropatellar joint, and the sham-operated contralateral C(3). ANIMALS: One mixed-breed pony and 5 Standardbred horses aged 3 to 8 years old. METHODS: Using instruments modified for equine use, four 4.5-mm-diameter osteochondral grafts were harvested arthroscopically from the distal aspect of the lateral trochlea of the right femur and inserted into the radial facet of the right third carpal bone. The fourth graft was kept as a donor-site control sample. Three months later, regular exercise was started and at 6 months, repeat arthroscopy was conducted to evaluate healing. The horses were euthanatized 9 months after transplantation, and comparisons were made between the grafts, opposing radial carpal bone, and contralateral third carpal bone. The assessment criteria included paravital staining, a modified Mankin scoring system, and biochemical analyses for collagen type, total collagen content, and sulfated glycosaminoglycan concentration. RESULTS: All horses were sound 21 days' postoperatively. At 6 months, all 18 grafts were intact but somewhat soft and opaque compared with surrounding carpal cartilage. Nine months' postoperatively, the bony portions of the grafts were well integrated with the recipient sites, but 6 grafts had histologic evidence of cartilage degeneration. From biochemical analysis of grafts, there was little or no new repair tissue invading the experimental sites, but sulfated glycosaminoglycan (proteoglycan) loss from the transplanted cartilage was marked. CONCLUSIONS: Heterotopic transfer of osteochondral grafts from the distal aspect of the lateral femoral trochlea to the third carpal bone is feasible with minor modifications of human mosaic arthroplasty instruments. The bony portion of the osteochondral grafts was quickly remodeled to provide subchondral support to the transplanted articular cartilage. The loss of proteoglycan from the transplanted cartilage indicates that the grafts might have been injured during harvesting or insertion, or, more likely, did not remodel to meet the demands of a new biomechanical environment. CLINICAL RELEVANCE: These findings suggest that arthroscopic resurfacing of focal osteoarticular defects will not be successful in the long term unless donor and recipient sites can be matched with respect to cartilage thickness, biochemical constituents, and physical properties. Mosaic arthroplasty may be indicated in selected cases in which no other options exist to create a confluent cartilage-covered surface.