In Vivo Activity of Genetically Modified Cells Preseeded in Rat Vascularized Composite Allografts.

OBJECTIVE: Transplantation of the hand or face, known as vascularized composite allotransplantation (VCA), has revolutionized reconstructive surgery. Notwithstanding, there are still several areas of improvement to mitigate immune rejection while sparing systemic adverse effects. The goal of this study was to evaluate the engraftment and viability of a genetically modified cell population pre-engrafted into a VCA transplant, to potentially act as a local biosensor to report and modify the graft in vivo. A rat fibroblast cell line genetically modified to secrete Gaussia-Luciferase (gLuc), which served as a constitutive biomarker of cells, was incorporated into a VCA to study the viability of biosensor cells in a syngeneic rat heterotopic partial hindlimb transplantation model. RESULTS: Five perfusions were first performed as engineering runs to have a stable limb perfusion protocol, followed by 3 perfusions to analyze the cell engraftment during machine perfusion, and finally 4 perfusions to study in vivo persistence of the cell biosensors. Blood samples were collected to monitor gLuc secretion during perfusion and postoperatively. A time-dependent increase in gLuc secretion in the limb perfusion outflow during machine perfusion indirectly verified the presence of biosensors within the graft. After the ex vivo perfusion, VCA hindlimbs were analyzed for near infrared fluorescence emission that showed a presence of dyed engineered cells in all areas of the limbs. Postoperatively, gLuc was detectable 4 to 5 days after transplantation (W = 16, P = .02857). This study demonstrated that engineered cells could be successfully preimplanted into VCAs-an important step toward development of an in vivo biosensor platform to use in modulating acute VCA outcomes.

Development of a three-dimensional computer model of the canine pelvic limb including cruciate ligaments to simulate movement.

Gait analysis as subjective visual assessment forms the foundation of the veterinarian's lameness examination. Pelvic limb lameness is frequently seen in dogs and the stifle joint with its cruciate ligaments, is a main cause of lameness due to cruciate ligament deficiency. In this study, we developed an open-source three-dimensional musculoskeletal pelvic limb model of a 30 kg Labrador Retriever including cruciate ligaments, simulating the gait cycle of the walking movement with the open-source programs NMSBuilder (Institutio Ortopedico Rizzoli, Bologna, Italy) and OpenSim (National Center for Simulation in Rehabilitation Research (NCSRR), Stanford, CA, USA). The computer model generated muscle activations based on motion data. The computed activations were similar to experimental electromyogram data. Highest joint torque was in extension/flexion in the stifle joint at 54 Nm at 14% of the gait cycle with cruciate ligaments. Highest stifle joint reaction force was 408 N at 16% of the gait cycle and was reduced after adding cruciate ligaments. Especially the cranial cruciate ligament loads up to 102 N (34% body weight). Cranial cruciate ligament forces increase with stifle extension and decrease with stifle flexion. On the contrary, the caudal cruciate ligament loads up to 27 N (9% body weight) during the swing phase with a flexed stifle joint. The model was validated with electromyogram data. The model's predictions are plausible because joint torques and forces match the applied ground reaction forces in curve progression and in timing. This model forms a basis for further investigations into stifle surgery after cruciate ligament deficiency.

Anatomy of the Tarsometatarsal Region and Digits in the Ostrich (Struthio Camelus): A Computed Tomography and Cross-Sectional Study.

The ostrich is the largest living bird and has unique characteristics in its locomotor system that differentiate it from other bird species. The purpose of this study was to provide a reference atlas of reference-interval computed tomography (CT) and cross-sectional anatomy of the tarsometatarsal region and digits in the ostrich (Struthio camelus). The pelvic limbs of 25 ostriches were used for this imaging study. The transverse CT images were obtained from the middle third of the tarsometatarsal bone to the distal end of the third digit. The specimens were frozen and sectioned with an electric band saw at 1.5-2 cm intervals. The CT images were compared with the corresponding frozen cross sections. The bones, ligaments, and tendons were identified and labeled at each 1.5-2 cm intervals. The CT images provided anatomic details of the tendons and ligaments in the tarsometatarsal region and digits of the ostrich. The transverse CT images provided an excellent depiction of the anatomic structures of the leg and foot when compared with the corresponding frozen cross sections. The information presented in this study may be used as an initial reference when evaluating the CT images of an ostrich's tarsometatarsal region and digits. Moreover, the information provided in this report may be helpful in determining definitive diagnoses of musculoskeletal disorders affecting the lower leg in this species.

Anatomia óssea e muscular do antebraço e mão de Chrysocyon brachyurus (Carnivora, Canidae) / Bone and muscular anatomy of the antibone and handof Chrysocyon brachyurus (Carnivora, Canidae)

O lobo-guará Chrysocyon brachyurus Illiger, 1815, é o maior canídeo da América do Sul, pesa cerca de 25 kg quando adulto e está ameaçado de extinção. Descrições anatômicas contribuem para a complementação das informações sobre espécies silvestres e para implicações conservacionistas, clínicas e cirúrgicas. Objetivou-se descrever os ossos e os músculos do antebraço e mão do lobo-guará. A preparação das peças foi feita a partir dos métodos usuais de dissecação, em animais preservados em solução de formol a 10%. Os espécimes pertencem ao acervo didático do Laboratório de Ensino e Pesquisa em Animais Silvestres da UFU e são provenientes de indivíduos atropelados. Os ossos descritos foram: rádio, ulna, ossos cárpico acessório, cárpico ulnar e cárpico intermédio; ossos cárpicos I, II, III e IV; ossos metacárpicos I, II, III, IV, V; falanges proximais, falanges médias e falanges distais do primeiro ao quinto dedo. Os músculos observados foram: extensor radial do carpo; pronador redondo; braquiorradial; extensor comum dos dedos; extensor ulnar do carpo; extensor lateral dos dedos; supinador; abdutor longo do dedo I; flexor radial do carpo; flexor profundo dos dedos; flexor superficial dos dedos; flexor ulnar do carpo; pronador quadrado; interflexor; lumbricais; abdutor curto dos dedos I e II e flexor curto do dedo I.

The maned wolf Chrysocyon brachyurus (Illiger, 1815) is the largest canid in South America, weighs about 25 kg as an adult and is threatened of extinction. Anatomical descriptions contribute to the complementation of information on wild species and for conservation, clinical and surgical implications. The purpose of this study was to describe the bones and muscles of the forearm and hand of the maned wolf. The methodology was through the usual dissecting methods in animals preserved in 10% formalin solution. The animals belong to the didactic collection of the Laboratory of Teaching and Research in Wild Animals of the UFU and come from run over. The bones evaluated were: radius, ulna, carpal accessory, carpi ulnar and carpi intermedium; carpal bones I, II, III and IV; metacarpal bones I, II, III, IV, V; proximal phalanges, middle phalanges and distal phalanges from first to fifth finger. The muscles observed were: radial extensor carpal; pronator round; brachioradial; common extensor of fingers; ulnar carpal extensor; lateral extensor of the fingers; supinator; abductor long finger I; flexor carpi radialis; flexor deep fingers; superficial flexor of the fingers; ulnar flexor of the carpus; square pronator; interflexor; lumbrils; short abductor of fingers I and II and short flexor of finger I.

Variations in Surgical Procedures for Inducing Hind Limb Ischemia in Mice and the Impact of These Variations on Neovascularization Assessment.

Mouse hind limb ischemia is the most common used preclinical model for peripheral arterial disease and critical limb ischemia. This model is used to investigate the mechanisms of neovascularization and to develop new therapeutic agents. The literature shows many variations in the model, including the method of occlusion, the number of occlusions, and the position at which the occlusions are made to induce hind limb ischemia. Furthermore, predefined end points and the histopathological and radiological analysis vary. These differences hamper the correlation of results between different studies. In this review, variations in surgical methods of inducing hind limb ischemia in mice are described, and the consequences of these variations on perfusion restoration and vascular remodeling are discussed. This study aims at providing the reader with a comprehensive overview of the methods so far described, and proposing uniformity in research of hind limb ischemia in a mouse model.

Are cursorial birds good kinematic models of non-avian theropods? / ¿Son los pájaros corredores buenos modelos cinemáticos de terópodos no aviares?

Determining kinematics of hindlimbs of theropod dinosaurs has been a challenge. Since cursorial birds are phylogenetically closest to theropod dinosaurs they are commonly used as a kinematic model of theropod dinosaur locomotion. Using a comparative biomechanical approach, we found that cursorial birds have a different morphology of legs than non avian theropodos and that appears to be that felines and ungulates share more morphological properties in the hindlimbs with theropod dinosaurs than cursorial birds. We calculated the ratio between the lower leg and the femur, and the relative length of the tibia and the metatarsus with respect to the length of the femur in cursorial birds, as well as felines, ungulates and non-avian theropods. We found that as the length of the femur increases, the length of the lower leg increases similarly in felines, ungulates and non-avian theropods. On the other hand, existing and extinct cursorial birds did not follow this pattern. This observation suggests that the hindlimb of cursorial birds are not well suited to serve as kinematic models for hindlimb of extinct theropod dinosaur locomotion.

Determinar la cinemática de los miembros pelvianos de los dinosaurios terópodos ha sido un desafío. Dado que las aves corredoras son filogenéticamente más cercanas a los dinosaurios terópodos, son comúnmente utilizadas como modelo cinemático de la locomoción del dinosaurio terópodo. Usando un enfoque biomecánico comparativo, encontramos que las aves corredoras tienen una morfología de pies diferente a la de los terópodos no aviares y parece ser que los felinos y los ungulados comparten más propiedades morfológicas en los pies con los dinosaurios terópodos que las aves corredoras. Calculamos la proporción entre la parte inferior de la pierna y el fémur, y la longitud relativa de la tibia y el metatarso con respecto a la longitud del fémur en aves corredoras, así como en los terópodos no aviares y ungulados. Encontramos que a medida que aumenta la longitud del fémur, la longitud de la parte inferior de la pierna aumenta de manera similar en los terópodos, los ungulados y los terópodos no aviares. Por otro lado, las aves corredoras existentes y extintas no siguieron este patrón. Esta observación sugiere que el miembro pelviano de las aves corredoras no es adecuada para servir como modelos cinemáticos de locomoción del miembro pelviano del dinosaurio terópodo extinto.

Functional Anatomy of the Craniomedial and Caudolateral Bundles of the Cranial Cruciate Ligament in Beagle Dogs.

OBJECTIVE: The aim of this study was to investigate detailed functional anatomy of the craniomedial bundle (CrMB) and caudolateral bundle (CdLB) of cranial cruciate ligament (CrCL) for application of intra-articular anatomical reconstruction in dogs. MATERIALS AND METHODS: Twelve stifle joint of 12 Beagle cadavers were used. Anatomical characteristics of femoral attachment regions of the CrCL were determined. Then, the location and area of the footprints of the CrMB and CdLB were objectively measured. Each bundle was equally divided into four fibre bundles, and changes in the fibre arrangement were recorded during stifle range of motion. Additionally, the tension of each fibre bundle at various stifle joint angles was objectively measured. RESULTS: The attachment region of the CrCL clearly differed from that reported in humans. The centre of the CdLB attachment site was located craniodistal to that of the CrMB on the femur and slightly caudal to that of the CrMB on the tibia. The area of the CrMB on the femoral and tibial attachment sites was larger than that of the CdLB. During stifle range of motion, each divided fibre bundle in the CrMB and CdLB was twisted intricately. The tension of the CrMB was higher than that of CdLB. The central part of the CrMB was always tense during stifle range of motion. CLINICAL SIGNIFICANCE: These results may contribute to the application of anatomical reconstruction surgery for CrCL deficient stifle in dogs.

A New Approach for Quantifying Radio-Biological Effects Using the Time Course of Mouse Leg Contracture.

A digitization approach to the time course of radiation-induced mouse leg contracture was proposed for quantifying the radiation effect on an individual living mouse. The shortening of the mouse leg length can be easily measured with a caliper/ruler to offer a very simple digitalized index of the radiation effect. Left hind legs of mice were irradiated with single dose of 32 Gy of 290 MeV carbon-ion beam using 0, 50, or 117 mm binary filter (BF). The right legs were used as a control. The lengths of both hind legs of the mice were measured using a digital caliper before irradiation and every week after irradiation. The degree of leg contracture, ΔSt, at the time point t was estimated by subtraction of the left irradiated leg length from the right control leg length. Equation was fitted on the daily time course of ΔSt, and two parameters, ΔSmax and Ts, were estimated. ΔSt=ΔSmax×(1-exp(t/Ts)), where ΔSmax is the maximum degree of leg contracture, and Ts is time of leg contracture. The effect of carbon-ion irradiation on a living mouse was quantified by ΔSmax and Ts of the leg contracture, and then compared to that of X-rays. By 32 Gy irradiation, ΔSmax was largest for the BF117 experiment, followed by X-ray~BF50>BF0. Ts was shortest for the BF50 experiment, while other irradiation conditions give similar Ts. A logarithmic function was successfully repurposed for the evaluation of radio-biological response.

Osteochondral repair using an acellular dermal matrix-pilot in vivo study in a rabbit osteochondral defect model.

The aim of this pilot project was to introduce a novel use of acellular dermal matrix (ADM) in combination with infrapatellar fat pad mesenchymal stromal cells (IPFP-MSCs) to effect repair in a rabbit osteochondral defect model. ADM, in a range of surgical procedures, has been shown to promote remodelling of tissue at the site of implantation. Rabbit-derived ADM (rabADM) was prepared from the skin of donor rabbits. Autologous IPFP-MSCs were obtained at the time of knee surgery. Osteochondral defects (4 mm cartilage outer/2 mm central bone defect) were drilled into distal femoral condyles of 12 New Zealand White rabbits. Treatments groups: (i) defect only; (ii) rabADM alone; (iii) IPFP-MSCs alone; and (iv) rabADM with IPFP-MSCs. Condyles were harvested at 12 weeks, and analyzed using histology, immunohistochemistry (types I and II collagen) and histomorphometry to evaluate osteochondral repair. The rabADM only group achieved the highest ratio of type II to non-type II collagen (77.3%) using areal measures (similar to normal cartilage), which indicated a higher quality of cartilage repair. The addition of IPFP-MSCs, with or without rabADM, formed a fibrous collagen cap above the lesion site not seen with rabADM alone. Macroscopically, there was no joint erosion, inflammation, swelling or deformity, and all animals maintained full range of motion. CONCLUSIONS: RabADM alone resulted in neocartilage formation similar to native cartilage. IPFP-MSCs limited osteochondral repair and contributed to fibrosis, even in combination with the rabADM. Further studies using ADM for osteochondral repair are warranted in a more appropriate pre-clinical model of osteochondral repair. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1919-1928, 2018.

Biomechanics and Microstructural Analysis of the Mouse Knee and Ligaments.

The purpose of this study is to determine the feasibility of using murine models for translational study of knee ligament injury, repair, and reconstruction. To achieve this aim, we provide objective, quantitative data detailing the gross anatomy, biomechanical characteristics, and microscopic structure of knee ligaments of 44 male mice (C57BL6, 12 weeks of age). Biomechanical testing determined the load-to-failure force, stiffness, and the site of ligament failure for the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and the medial and lateral collateral ligaments (MCL and LCL). These data are complemented by histological characterization of each of the knee ligaments. In addition, the osseous morphology of the mouse knee was examined using high-resolution nanofocus computed tomography (CT), while standard micro-CT was employed to measure bone morphometrics of the distal femur and proximal tibia. Collectively, our findings suggest that the gross anatomy of the mouse knee is similar to the human knee despite some minor differences and features unique to the murine knee. The ACL had the highest load to failure (5.60 ± 0.75 N), the MCL (3.33 ± 1.45 N), and the PCL (3.45 ± 0.84 N) were similar, and the LCL (1.44 ± 0.37 N) had the lowest load to failure and stiffness. Murine models provide a unique opportunity to focus on biological processes that impact ligament pathology and healing due to the availability of transgenic strains. Our data support their use as a translational platform for the in vivo study of ligament injury, repair, and reconstruction.

Radiographic Anatomy of the Metatarsophalangeal Joint and Digits of the Ostrich (Struthio camelus).

The aim of this study was to develop a detailed and accessible set of reference images of the normal radiographic anatomy of the digits of the ostrich (Struthio camelus), with emphasis on the metatarsophalangeal joint and its arthrography. The distal excised pelvic limbs of 10 normal ostriches of different ages (ranging from 10 to 365 days of age) obtained from an abattoir were radiographed, and 2 arthrograms were performed. To illustrate the normal radiographic anatomy of the tarsometatarsal bone, 39 images were selected, labelled, and presented along with detailed descriptions and corresponding images of the bony skeleton. These results provide a valuable dataset to assist in understanding the normal anatomy of the ostrich metatarsophalangeal joint and digits and allow comparison of abnormal corresponding structures in clinical cases in ostriches.

An anatomical and histological study of the equine proximal manica flexoria.

OBJECTIVES: The main aim was to describe the gross and histological appearance of the equine manica flexoria and to identify any differences between the forelimbs and hindlimbs. An additional aim was to relate the findings to diagnostic and surgical anatomy of the manica flexoria. METHODS: Measurements of the manica flexoria were made on cadaveric limbs from horses free from pathology within the digital flexor tendon sheath. Histological sections, stained with haematoxylin and eosin and alcian- periodic acid schiff, were evaluated based on three micro-anatomical zones from dorsal to palmar or plantar. The prevalent tenocyte morphology, number, and distribution of blood vessels and nerves were described in each zone. Forelimb and hindlimb measurements were compared using a Students T-test. RESULTS: Proximally, the manica flexoria attaches to the digital flexor tendon sheath via a reflection of areolar tissue. The fibrous manica flexoria is longer in the forelimb (32.0 ± 4.2 mm) than the hindlimb (29.4 ± 3.8 mm) (p = 0.04), with the areolar portion longer in the hindlimb (22.9 ± 5.3 mm) compared to the forelimb (16.7 ± 4.3 mm) limb (p = 0.0005). Histologically, degenerate blood vessels were prevalent in the palmar/plantar regions and were associated with chondrocyte-like tenocytes, indicative of fibrocartilagenous metaplasia. CLINICAL SIGNIFICANCE: The study has provided a detailed anatomical description of the manica flexoria relevant for interpretation of diagnostic and surgical evaluation. Fibrocartilaginous metaplasia occurs on the palmar/plantar surfaces of the manica flexoria.

Fluorescence Imaging In Vivo at Wavelengths beyond 1500†nm.

Compared to imaging in the visible and near-infrared regions below 900 nm, imaging in the second near-infrared window (NIR-II, 1000-1700 nm) is a promising method for deep-tissue high-resolution optical imaging in vivo mainly owing to the reduced scattering of photons traversing through biological tissues. Herein, semiconducting single-walled carbon nanotubes with large diameters were used for in vivo fluorescence imaging in the long-wavelength NIR region (1500-1700 nm, NIR-IIb). With this imaging agent, 3-4 µm wide capillary blood vessels at a depth of about 3 mm could be resolved. Meanwhile, the blood-flow speeds in multiple individual vessels could be mapped simultaneously. Furthermore, NIR-IIb tumor imaging of a live mouse was explored. NIR-IIb imaging can be generalized to a wide range of fluorophores emitting at up to 1700 nm for high-performance in vivo optical imaging.

Cephalic and limb anatomy of a new Isoxyid from the Burgess Shale and the role of "stem bivalved arthropods" in the disparity of the frontalmost appendage.

We herein describe Surusicaris elegans gen. et sp. nov. (in Isoxyidae, amended), a middle (Series 3, Stage 5) Cambrian bivalved arthropod from the new Burgess Shale deposit of Marble Canyon (Kootenay National Park, British Columbia). Surusicaris exhibits 12 simple, partly undivided biramous trunk limbs with long tripartite caeca, which may illustrate a plesiomorphic "fused" condition of exopod and endopod. We construe also that the head is made of five somites (= four segments), including two eyes, one pair of anomalocaridid-like frontalmost appendages, and three pairs of poorly sclerotized uniramous limbs. This fossil may therefore be a candidate for illustrating the origin of the plesiomorphic head condition in euarthropods, and questions the significance of the "two-segmented head" in, e.g., fuxianhuiids. The frontalmost appendage in isoxyids is intriguingly disparate, bearing similarities with both dinocaridids and euarthropods. In order to evaluate the relative importance of bivalved arthropods, such as Surusicaris, in the hypothetical structuro-functional transition between the dinocaridid frontal appendage and the pre-oral-arguably deutocerebral-appendage of euarthropods, we chose a phenetic approach and computed morphospace occupancy for the frontalmost appendages of 36 stem and crown taxa. Results show different levels of evolutionary decoupling between frontalmost appendage disparity and body plans. Variance is greatest in dinocaridids and "stem bivalved" arthropods, but these groups do not occupy the morphospace homogeneously. Rather, the diversity of frontalmost appendages in "stem bivalved" arthropods, distinct in its absence of clear clustering, is found to link the morphologies of "short great appendages," chelicerae and antennules. This find fits the hypothesis of an increase in disparity of the deutocerebral appendage prior to its diversification in euarthropods, and possibly corresponds to its original time of development. The analysis of this pattern, however, is sensitive to the-still unclear-extent of polyphyly of the "stem bivalved" taxa.

Description of the Anatomy, Surgical Technique, and Outcome of Hemipelvectomy in 4 Dogs and 5 Cats.

OBJECTIVE: To provide (1) a comprehensive description of hemipelvectomy; and (2) report clinical application and outcome of hemipelvectomy in dogs and cats. STUDY DESIGN: Descriptive report and retrospective case series. ANIMALS: Dogs (n = 4) and 5 cats. METHODS: Cadaveric dissection was performed for imaging purposes using 4 mixed breed dogs euthanatized for reasons unrelated to this study. Medical records (2005-2012) were reviewed for dogs and cats that had hemipelvectomy. Data collected included signalment, body weight, body condition score, clinical presentation, diagnostic imaging findings, location and extent of tumor, definitive diagnosis, use of adjuvant therapy, ability to ambulate postoperatively, complications, and survival. RESULTS: The most common indication for hemipelvectomy in cats was injection site sarcoma (ISS) and in dogs, osteosarcoma or peripheral nerve sheath tumor (PNST). Complete tumor excision was achieved in 6 (67%) cases. Incomplete excision occurred in 2 dogs with lumbosacral PNST and 1 cat having a 2nd surgery for ISS. Complications included intraoperative hemorrhage (n = 2), postoperative soft tissue infection (2), and discharge from the incision site (1). All but 1 animal were ambulatory at the time of discharge. Hospitalization ranged from 1-10 days (median, 4 days). Survival after surgery was individually assessed. CONCLUSION: With in-depth anatomic familiarity, hemipelvectomy can be successful for excision of neoplastic lesions of the proximal aspect of the pelvic limb, with only minor complications.

Three dimensional morphologic analysis of the lateral surface of the canine femur.

OBJECTIVES: Analyze the lateral plating surface of the femur to obtain bend and twist angles in dogs with non-chondrodystrophic phenotype. STUDY DESIGN: Retrospective computed tomography (CT) morphologic analysis. SAMPLE POPULATION: Historical cohort, hindlimb CT scans (n = 30). MATERIALS AND METHODS: The CT images of 30 normal femurs were uploaded to surgical planning software and 13 points of interest and their respective bend/twist angles were identified on the lateral surfaces. Mean, standard deviation, coefficient of variation (CV), and range were calculated for each bend/twist angle. Hierarchal clustering and fast Fourier Analyses were used to segment the cohort. Distribution of age, breed, sex, and weight was evaluated between clusters with an exact Wilcoxon-Mann-Whitney test. RESULTS: The CV of bending ranged from 17% to 46% and for twisting ranged from 21% to 58%. The greater trochanter was the most pronounced bend on the lateral surface of the femur (mean ± SD 8.11 ± 1.35°, CV 17%), and the supracondylar region of the distal femur was the most marked twist (mean ± SD 48.98 ± 10.06°, CV 21%). Although there were no differences between dogs in proximal femur anatomy, 2 clusters of 9 and 21 dogs each were identified due to differences in bend/twist angles in the distal femur. There was no difference between clusters for age (P = .85), breed (P = .62), and sex (P = .15); however, weight differed (P = .03) but was not predictive. CONCLUSION: Although distal femoral lateral surfaces varied sufficiently to result in 2 population clusters, further analysis is needed to determine if the differences prevent using the mean bending and twisting parameters as a template for clinical applications.

Magnetic resonance imaging, computed tomography, and gross anatomy of the canine tarsus.

OBJECTIVES: To describe the normal anatomy of the soft tissues of the canine tarsus as identified on computed tomography (CT) and magnetic resonance imaging (MRI) and to evaluate specific MRI sequences and planes for observing structures of diagnostic interest. STUDY DESIGN: Prospective descriptive study. ANIMALS: Canine cadavers (n = 3). METHODS: A frozen cadaver pelvic limb was used to trial multiple MRI sequences using a 1.5 T superconducting magnet and preferred sequences were selected. Radiographs of 6 canine cadaver pelvic limbs confirmed the tarsi were radiographically normal. A 16-slice CT scanner was used to obtain 1 mm contiguous slices through the tarsi. T1-weighted, proton density with fat suppression (PD FS) and T2-weighted MRI sequences were obtained in the sagittal plane, T1-weighted, and PD FS sequences in the dorsal plane and PD FS sequences in the transverse plane. The limbs were frozen for one month and sliced into 4-5 mm thick frozen sections. Anatomic sections were photographed and visually correlated to CT and MR images. RESULTS: Most soft tissue structures were easiest to identify on the transverse MRI sections with cross reference to either the sagittal or dorsal plane. Bony structures were easily identified on all CT, MR, and gross sections. CONCLUSIONS: The anatomy of the canine tarsus can be readily identified on MR imaging.

Innervation mapping of the hind paw of the rat using Evans Blue extravasation, Optical Surface Mapping and CASAM.

BACKGROUND: Although numerous studies investigate sensory regeneration and reinnervation of the hind paw of the rat after nerve damage, no comprehensive overview of its normal innervation is present in literature. The Evans Blue extravasation technique is a well-known technique to study patterns of skin innervation. This technique has been performed differently by various groups but was never used to study the entire skin innervation in rats' hind paw including all three branches of the sciatic nerve and the saphenous nerve in detail. NEW METHOD: In this paper, we have used the Evans Blue extravasation technique to chart the skin areas innervated by the sural, peroneal, tibial and/or saphenous nerves, which together innervate the entire hind paw of the rat, and use a new technique to analyze the distribution, overlap and variability of the results. The technique is based on analysis of whole hind paws using Optical Surface Mapping (OSM) in combination with the Computer Assisted Surgical Anatomy Mapping (CASAM) technology. RESULTS: While the plantar hind paw is mainly innervated by the tibial nerve, the dorsal hind paw is supplied by the sural, peroneal and the saphenous nerve. COMPARISON WITH EXISTING METHODS: Although our results basically concur with the general nerve-specific innervation of the rat hind paw, they show considerable detail in their areas of overlap as well as in the amount of variability between animals. CONCLUSION: These results will be invaluable to study and evaluate patterns of innervation and reinnervation of intact and damaged nerve fibers.

Determination of the normal arthroscopic anatomy of the femoropatellar and cranial femorotibial joints of cattle.

The arthroscopic approach and anatomy of the bovine femoropatellar and femorotibial joints are described. A 4-mm diameter, 15-cm long arthroscope with a 30° forward angle view was used. The structures viewed were recorded according to the position of the arthroscope within the joint. The femoropatellar joint was best accessed via a lateral approach, between the middle and lateral patellar ligaments. The axial portion of the medial femorotibial joint was viewed from a medial approach between the middle and medial patellar ligaments and the abaxial portion was viewed from a lateral approach between the middle and the lateral patellar ligaments. The axial portion of the lateral femorotibial joint was viewed from a lateral approach between the middle and the lateral patellar ligaments and the abaxial portion was viewed from a medial approach between the middle and medial patellar ligaments. The results of this study provide guidelines regarding the location of arthroscopic portals to evaluate precisely different areas of the stifle in cattle.

Détermination de l'anatomie arthroscopique normale des articulations fémoropatellaire, et fémorotibiales, compartiments craniaux, chez les bovins. Les approches arthroscopiques et l'anatomie des articulations fémoropatellaire et fémorotibiales des bovins sont décrites dans cet article. Un arthroscope de 4 mm de diamètre et d'une longueur de 15 cm avec un angle de visionnement de 30 degré a été utilisé. La position de l'arthroscope a été notée pour chaque structure visualisée. L'articulation fémoropatellaire était pénétrée par une approche latérale, entre les ligaments patellaires médian et latéral. La portion axiale de l'articulation fémorotibiale médiale était pénétrée par une approche médiale entre les ligaments patellaire médian et médial et la portion abaxiale était pénétrée par une approche latérale entre les ligaments patellaires médian et latéral. La portion axiale de l'articulation fémorotibiale latérale était pénétrée par une approche latérale entre les ligaments patellaires médian et latéral et la portion abaxiale était pénétrée par une approche médiale entre les ligaments patellaires médian et médiale. Les résultats de cette étude s'avère être un guide afin d'utiliser la meilleure approche arthroscopique pour évaluer précisément certaines structures du grasset bovin.(Traduit par les auteurs).

Orthogonal resonators for pulse in vivo electron paramagnetic imaging at 250 MHz.

A 250 MHz bimodal resonator with a 19 mm internal diameter for in vivo pulse electron paramagnetic resonance (EPR) imaging is presented. Two separate coaxial cylindrical resonators inserted one into another were used for excitation and detection. The Alderman-Grant excitation resonator (AGR) showed the highest efficiency among all the excitation resonators tested. The magnetic field of AGR is confined to the volume of the detection resonator, which results in highly efficient use of the radio frequency power. A slotted inner single loop single gap resonator (SLSG LGR), coaxial to the AGR, was used for signal detection. The resulting bimodal resonator (AG/LGR) has two mutually orthogonal magnetic field modes; one of them has the magnetic field in the axial direction. The resonator built in our laboratory achieved 40 dB isolation over 20 MHz bandwidth with quality factors of detection and excitation resonators of 36 and 11 respectively. Considerable improvement of the B1 homogeneity and EPR image quality in comparison with reflection loop-gap resonator of similar size and volume was observed.