Gross osteology and radiology of the pelvic limb of the adult small East African goat

The aim of this study was to provide the detailed normal gross osteology and radiographic anatomy of the pelvic limb in adult small East African goats as a reference for clinical use, biomedical research and teaching. Radiography of the pelvic limb was performed in five adult small East African goats. Bone specimens of four skeletally mature small East African goats were used for gross osteological study. The ilial wing was wide. The ischiatic tuberosity was prominent and well developed. The acetabulum was rounded. The minor trochanter was located caudomedially, and the femoral trochlea was deep and narrow. The lateral and medial condyles of the femur were approximately of the same size. The tibial tuberosity was prominent, and the cochlea grooves were deep with a pronounced intermediate ridge. The trochlea of the talus was deep. The patella presented a prominent tuberosity on the cranial surface. The metatarsal sesamoid bone was seen in all animals. The observed gross osteology and radiographic anatomy of the pelvic limb of small East African goats was consistent with the presence of strong extensor muscles of the hip, stifle and tarsus for propulsion during terrestrial walking and trotting.     

XERORADIOGRAPHIC ANATOMY OF THE EQUINE DIGIT AND METACARPOPHALANGEAL REGION

The purpose of the project was to use xeroradiography to provide a reference for radiographic anatomy of the equine digit and metacarpophalangeal region. The left foredigits and metacarpophalangeal joints of a mature horse and a 30-day-old foal were radiographed, using xeroradiographic techniques. Fifteen xeroradiographs, illustrating standard projections of each area, were selected and appropriately labeled to demonstrate normal radiographic anatomy of these regions. These xeroradiographs have been used successfully for several years to teach radiographic anatomy of these areas to first-year veterinary students at North Carolina State University.     

THE NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE COCKATIEL (NYMPHZCUS HOLLANDZS)

The purpose of the study was to provide a reference for the normal radiographic anatomy of the cockatiel ( Nymphicus hollundis ). The head, body, wing, and pelvic limb of mature males were radiographed using xeroradiographic and conventional radiographic techniques. Ten xeroradiographs and ten corresponding conventional radiographs were selected, and the xeroradiographs appropriately labeled to illustrate the normal radiographic anatomy of these regions.     

COMPUTED TOMOGRAPHIC ANATOMY OF THE DISTAL EXTREMITY OF THE HORSE

X-ray computed tomography (CT) is an imaging tool that is becoming increasingly available for use in veterinary medicine. Advantages, including depiction of detailed cross-sectional anatomy, improved contrast resolution, and computer reformatting, make it a potentially valuable diagnostic technique. Veterinary application of CT has been primarily limited to use in small animals. Current reports describe the technique for use in the horse, but there are no published studies correlating serial CT images with equine cross-sectional anatomy. A study of the distal extremity of the horse was undertaken to facilitate interpretation of images produced using CT. Transverse CT images of the distal forelimb of equine cadavers were evaluated relative to gross anatomic dissection. Resolution of bone architecture in transverse plane images was satisfactory, but soft-tissue' resolution, although satisfactory for visualization of major structures, was relatively poor, probably due to lack of interposed fat and insufficient differences in physical density and atomic number. Thus it appears in the equine distal limb that CT may be most useful for evaluation of complex bone abnormalities.     

Radiographic interpretation of normal skeletal variations and pseudolesions in the equine foot.

Effective radiographic interpretation requires a veterinarian who is knowledgeable of equine limb anatomy and the various principles that affect the resulting image. The normal and its variations must be recognized and understood before the abnormal can be confidently identified as pathologic. Proper patient positioning and sound radiographic technique are mandatory if reliable diagnostic radiographs are to be produced. This review emphasizes equine foot radiographic variations of normal and pseudolesions that occur with commonly used radiographic views performed in equine practice.     

NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE MALLARD DUCK (ANAS PLATYRHYNCHOS) WITH REFERENCE TO OTHER ANSERINE SPECIES

The purpose of this study was to provide a reference for xeroradiographic and conventional radiographic anatomy of the mallard duck ( Anas platyrhynchos ) as a representative of the avian Order Anseriformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Nine xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate normal anatomy. Selected views of other anseriform species were included to illustrate certain anatomical features unique to those species.     

NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE GREAT HORNED OWL (BUBO VIRGINIANUS), WITH SPECIAL REFERENCE TO THE BARN OWL (TYTO ALBA)

The purpose of this study was to provide a reference for xeroradiographic and conventional radiographic anatomy of the great horned owl ( Bubo virginianus ) as a representative of the avian Order Strigiformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Twelve xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate normal anatomy. Selected views of the barn owl ( Tyto alba ) were included to illustrate significant differences between this and other species of owls.     

THE NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE ORANGE-WINGED AMAZON PARROT (AMAZONA AMAZONICA AMAZONICA)

The purpose of the study was to provide a reference for xeroradiographic and conventional radio-graphic anatomy of the orange-winged Amazon parrot ( Amazona amazonica amazonica ) as a representative of medium-sized psittacine birds that are commonly kept as pets. The head, body, wing, and pelvic limb of a mature bird were radiographed using xeroradiographic and conventional radiographic techniques. Ten xeroradiographs and ten corresponding radiographs were selected, and the xeroradiographs labeled to illustrate the normal radiographic anatomy of these regions. Also included is a short discussion of unique avian anatomic features which are important to clinical evaluation.     

Morphology of the thoracic limb of goat as evidenced by gross osteology and radiology

The objective of this study was to provide the detailed normal gross osteology and radiographic anatomy of the thoracic limb in goats as a reference for clinical use and in biomedical research. Radiography of the thoracic limb was performed in five small East African goats. Radiographic findings were correlated with bone specimens from four adult small East African goats. The scapula was narrow. The major tubercle was large and extended proximally above the head of the humerus. The lateral supracondylar crest was less prominent. The lateral and medial epicondyles of the humerus were almost of the same size. The lateral surface of the lateral condyle of the humerus presented a prominent depression for the origin of extensors of the carpus and digits. The cranially located radial notch was deep seated and the radial tuberosity was represented by a rough area located nearer to the head of the radius. The fifth metacarpal bone was seen in all animals. The morphology of the thoracic limb of small East African goats indicated the presence of powerful extensor muscles and is restricted to forward and backward movements as an adaptation to terrestrial lifestyle.     

NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE RED-TAILED HAWK (BUTEO JAMAICENCIS), WITH REFERENCE TO OTHER DIURNAL RAPTORS

The purpose of this study was to provide a reference for xeroradiographic and conventional radio-graphic anatomy of the red-tailed hawk (Buteo jamaicencis) as a representative of the avian Order Falconiformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Twelve xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate the normal anatomy of these regions.     

FEASIBILITY OF ULTRASOUND‐GUIDED EPIDURAL ACCESS AT THE LUMBO‐SACRAL SPACE IN DOGS

Epidural injections are commonly performed blindly in veterinary medicine. The aims of this study were to describe the lumbosacral ultrasonographic anatomy and to assess the feasibility of an ultrasound‐guided epidural injection technique in dogs. A cross sectional anatomic atlas of the lumbosacral region and ex vivo ultrasound images were obtained in two cadavers to describe the ultrasound anatomy and to identify the landmarks. Sixteen normal weight canine cadavers were used to establish two variations of the technique for direct ultrasound‐guided injection, using spinal needles or epidural catheters. The technique was finally performed in two normal weight cadavers, in two overweight cadavers and in five live dogs with radiographic abnormalities resulting of the lumbosacral spine. Contrast medium was injected and CT was used to assess the success of the injection. The anatomic landmarks to carry out the procedure were the seventh lumbar vertebra, the iliac wings, and the first sacral vertebra. The target for directing the needle was the trapezoid‐shaped echogenic zone between the contiguous articular facets of the lumbosacral vertebral canal visualized in a parasagittal plane. The spinal needle or epidural catheter was inserted in a 45° craniodorsal–caudoventral direction through the subcutaneous tissue and the interarcuate ligament until reaching the epidural space. CT examination confirmed the presence of contrast medium in the epidural space in 25/25 dogs, although a variable contamination of the subarachnoid space was also noted. Findings indicated that this ultrasound‐guided epidural injection technique is feasible for normal weight and overweight dogs, with and without radiographic abnormalities of the spine.     

RADIOGRAPHIC PROTOCOL AND NORMAL ANATOMY OF THE HIND FEET IN THE WHITE RHINOCEROS (CERATOTHERIUM SIMUM)

Foot pathology is a common and important health concern in captive rhinoceroses worldwide, but osteopathologies are rarely diagnosed, partly because of a lack of radiographic protocols. Here, we aimed to develop the first radiographic protocol for rhinoceros feet and describe the radiographic anatomy of the white rhinoceros (Ceratotherium simum) hind foot (pes). Computed tomographic images were obtained of nine cadaver pedes from seven different white rhinoceroses and assessed for pathology. A single foot deemed free of pathology was radiographed using a range of different projections and exposures to determine the best protocol. 3D models were produced from the CT images and were displayed with the real radiographs to describe the normal radiographic anatomy of the white rhinoceros pes. An optimal radiographic projection was determined for each bone in the rhinoceros pes focusing on highlighting areas where pathology has been previously described. The projections deemed to be most useful were D60Pr‐PlDiO (digit III), D45Pr45M‐PlDiLO (digit II), and D40Pr35L‐PlDiLO (digit IV). The primary beam was centered 5–7 cm proximal to the cuticle on the digit of interest. Articular surfaces, ridges, grooves, tubercles, processes and fossae were identified. The radiographic protocol we have developed along with the normal radiographic anatomy we have described will allow for more accessible and effective diagnosis of white rhinoceros foot osteopathologies.     

The anatomy and physiology of the avian endocrine system.

The endocrine system of birds is comparable to that of mammals, although there are many unique aspects to consider when studying the anatomy, physiology, and biochemistry. Avian endocrinology is a field of veterinary medicine that is unfamiliar to many practitioners; however, it is important to have a comprehensive understanding when evaluating companion birds in clinical practice. This article covers the anatomy and physiology of the normal avian, and readers are referred to other articles for a more detailed explanation of altered physiology and pathology.     

SCINTIGRAPHIC EVALUATION OF THE DISTAL TARSAL REGION IN HORSES WITH DISTAL TARSAL PAIN

Distal tarsal pain is a common reason for hind limb lameness, but diagnosis cannot always be made on radiographic examination. Scintigraphy may allow detection of subtle changes undetected by other diagnostic methods. We hypothesized that (1) distal tarsal pain would be associated with a loss of the expected pattern of radiopharmaceutical uptake (RU) detected in normal horses, (2) distal tarsal RU would be greater in limbs with tarsal pain than without pain, (3) RU in painful tarsi with radiographic evidence of osteoarthritis (OA) would be greater than in distal tarsal pain with no radiographic evidence of OA. The study aimed to describe radiopharmaceutical distribution in the distal tarsal region of horses with distal tarsal pain, and to compare this with the contralateral limb and results from horses without tarsal pain. Retrospective evaluation of scintigraphic images of the distal tarsal region was performed for 52 horses with distal tarsal pain: 15 with no radiographic evidence of OA (Group 1) and 37 with radiographic evidence (Group 2). The images were assessed using vertical and horizontal profile analysis across the distal tarsal region and regions of interest comparisons between the distal tarsal region and tibia within each horse (RU ratio). Painful limbs in unilaterally lame horses from Groups 1 and 2 had a significantly greater RU ratio than the respective contralateral limbs, and were significantly greater than the RU ratio in normal horses. On plantar images, mean region of interest counts were greater in the lame than the contralateral limb in Group 2 but not in Group 1. Although there was a positive correlation between lame and contralateral limb RU ratio in group 1, this was lost in group 2 horses. In lame limbs, the normal vertical activity profile was lost in 85% of group 1 and all of group 2, and the normal horizontal activity profile was lost in all of group 1 and 96% of group 2. There was a significant effect of lameness, but not of group on sites of peak activity on all profiles. The results of this study indicate that distal tarsal pain is associated with loss of the expected pattern of RU detected in normal horses. The findings also suggest that distal tarsal RU in lame limbs is greater than in limbs without pain, and that painful limbs with radiographic evidence of OA have a greater RU than painful limbs without radiographic evidence of OA.     

Computed Tomography and Cross‐Sectional Anatomy of the Metatarsus and Digits of the One‐humped Camel ( Camelus dromedarius) and Buffalo ( Bos bubalis)

The purpose of the present study was to provide a detailed computed tomography (CT) and cross‐sectional anatomic reference of the normal metatarsus and digits for the camel and buffalo, as well as to compare between metatarsus and digits in these animals to outstand a basis for diagnosis of their diseases. Advantages, including depiction of detailed cross‐sectional anatomy, improved contrast resolution and computer reformatting, make it a potentially valuable diagnostic technique. The hind limbs of 12 healthy adult camel and buffalo were used. Clinically relevant anatomic structures were identified and labelled at each level in the corresponding images (CT and anatomic slices). CT images were used to identify the bony and soft tissue structures of the metatarsus and digits. The knowledge of normal anatomy of the camel and buffalo metatarsus and digits would serve as initial reference to the evaluation of CT images in these species.     

Magnetic Resonance Imaging (MRI) Anatomy of the Ovine Lumbar Spine

Although the ovine spine is a useful research model for intervertebral disc pathology and vertebral surgery, there is little peer‐reviewed information regarding the MRI anatomy of the ovine spine. To describe the lumbar spine MRI anatomy, 10 lumbar segments of cadaver ewes were imaged by 1.5‐Tesla MR. Sagittal and transverse sequences were performed in T1 and T2 weighting (T1W, T2W), and the images were compared to gross anatomic sagittal and transverse sections performed through frozen spines. MRI was able to define most anatomic structures of the ovine spine in a similar way as can be imaged in humans. In both T1W and T2W, the signals of ovine IVDs were similar to those observed in humans. Salient anatomic features were identified: (1) a 2‐ to 3‐mm linear zone of hypersignal was noticed on both extremities of the vertebral body parallel to the vertebral plates in sagittal planes; (2) the tendon of the crura of the diaphragm appeared as a hypointense circular structure between hypaxial muscles and the aorta and caudal vena cava; (3) dorsal and ventral longitudinal ligaments and ligamentum flavum were poorly imaged; (4) no ilio‐lumbar ligament was present; (5) the spinal cord ended between S1–S2 level, and the peripheral white matter and central grey matter were easily distinguished on T1W and T2W images. This study provides useful reference images to researchers working with ovine models.     

Angiographic Anatomy of External Iliac Arteries in the Sheep

External iliac artery atherosclerotic disease and aneurism occur in man. For treatment, imaging is required to facilitate minimally invasive introduction and advancement of stents within the intended vessels. Sheep are commonly used to test and improve stents. However, little information is published regarding the angiographic anatomy of the iliac arteries in the ovine species. The objective of this study was to describe the angiographic anatomy of the iliac arteries in the sheep. Computed tomography (CT) angiography and gross anatomical dissection were performed in, respectively, 10 and 43 adult ewes. Diameters and lengths of the arteries were measured. In comparison with man, salient anatomical differences were identified in the sheep: (1) the absence of common iliac arteries, (2) the common trunk at the origin of internal iliac arteries and (3) the location of the bifurcation of the external iliac arteries into femoral arteries in the pelvis (not in the limb). External iliac arteries in this series of sheep were 86 mm long in average and had a mean diameter of 7.5 mm. Lengths of arteries are only slightly different between man and sheep, while diameters are rather similar. Therefore, the sheep model appears to be sufficiently similar to man to test stent properties. This study provides useful reference images and measures of lengths and diameters of relevant arteries that could be applied to research with ovine models.     

Utility of two‐view vs. three‐view abdominal radiography in canines presenting with acute abdominal signs

There are clear differences in the normal radiographic appearance of the abdominal organs between a left lateral vs. a right lateral view. While a few veterinary academic institutions have transitioned to a three‐view abdominal radiographic study protocol, obtaining only two views of the canine abdomen remains the current standard in veterinary medicine. In this combined retrospective and prospective, case‐controlled study, 48 canine patients presenting with signs of acute abdomen were recruited. Four board‐certified veterinary radiologists and four general practice veterinarians with greater than 3 years of experience in small animal practice were asked to determine if 10 predetermined findings were present within the set of images and if surgery was recommended based on those findings. Image readers were unaware of the clinical history. Three‐view studies did not yield statistically significantly greater accuracy than two‐view studies when evaluating all readers together. No statistically significant associations between the availability of the third view and increased accuracy or confidence were found in evaluations of general practitioners specifically. Evaluation of three‐view radiographic examination, as compared to two‐view examination, did not have perceived or statistically significantly increased diagnostic utility. Based on our findings, there is no statistically increased utility to justify a standard three‐view abdominal radiographic examination over a two‐view study for canines presenting with signs of acute abdomen.