The intercondylar fossa indices of male and female dog femora.

The intercondylar fossa (ICF) indices can be used to evaluate fossa geometry, which may in turn affect the function, pathology and intracapsular surgical repair of the cranial cruciate ligament. The measurements of digital images of the distal femur of 44 dogs were used to calculate the fossa width, shape, height and area indices. The mean values of fossa width index were found to be 0.19, 0.28 and 0.37 at the cranial, central, and caudal levels of the fossa, respectively. The mean values for fossa shape, height and area indices were found to be 0.71, 0.33, and 0.16, respectively. The differences in ICF indices between male and female dog were not significant. Therefore, it is suggested that gender differences related to ICF geometry may not have any effect on incidence of cranial cruciate ligament injury in dogs.

The effects of ovariectomy on bone mineral density, geometrical, and biomechanical characteristics in the rabbit femur.

The aim of the study was to evaluate the bone mineral density, as well as the biomechanic and morphometric changes in the femur of ovariectomised rabbits. Twenty-four six-month-old New Zealand rabbits were randomly divided into an ovariectomy (n = 12) and a sham (n = 12) group. Six rabbits in each group were euthanatized at eight and 16 weeks after surgery, and the femora were resected. The morphometric data were obtained from tomographic images. Periosteal and endosteal diameters and cortical thickness were measured. Total cross- sectional, cortical and medullary areas were also measured. The bone mineral content, the bone area and the bone mineral density were measured from the proximal, distal and midshaft of the femur as well as the total femur by dual energy X-ray absorptiometry. Employing the three-point bending method, the ultimate force, stiffness and work-to-failure were measured. The mechanical data were normalised to obtain intrinsic biomechanical properties such as ultimate stress, elastic modulus, and toughness, all of which are independent of size and shape. The results indicated that the femur was both larger and weaker 16 weeks after surgery in the ovariectomised group. Results also suggest that the rabbit might be a useful animal model for investigation of diseases related to oestrogen loss such as human postmenopausal osteoporosis. However, additional studies with advanced techniques at several time points via in vivo animal studies, and precision and predictability analyses should be designed to standardise the rabbit as a model for osteoporosis.

Computed tomographic measurements of the hip morphology of 10 healthy German shepherd dogs.

Linear measurements were made by computed tomography of the diameter of the femoral head, the width and depth of the acetabulum and the dorsal and ventral acetabular rim distances in 10 healthy German shepherd dogs, and angular measurements were made of the axial acetabular index, acetabular anteversion, and the dorsal and ventral centre-edge angles. There were no significant differences between the measurements made on the left and right sides. The width of the acetabulum was about twice its depth, and was a little larger than the diameter of the femoral head. The mean values of the axial acetabular index, acetabular anteversion, and ventral and dorsal centre-edge angles were 100.9 degrees, 25.1 degrees, 48.0 degrees and 12.2 degrees, respectively.

Morphometry of the thoracic spine in German shepherd dog: a computed tomographic study.

Computed tomographic images of the thoracic spine of 13 German shepherd dogs were examined in order to determine the thoracic spine morphometry. Examinations were carried out in the transverse plane both intervertebral and mid-vertebral levels of the each thoracic vertebrae. The dorsoventral and interpedicular diameters of the spinal canal, the dorsoventral and transverse diameters of the vertebral body, the dorsoventral and transverse diameters of the spinal cord and also the cross-section area of the spinal canal were measured. The maximum values were found to be at the level of C7-T1. The shapes of the spinal canal and cord were circular in middle part, the shape became transverse oval in the cranial and caudal parts of the thoracic spine. The most significant correlation between the diameters was found to be in male dogs, except between dorsoventral diameters of the spinal canal and that of the vertebral body and between dorsoventral diameters of the spinal canal and transverse diameters of the vertebral body.

Computed tomographic pelvimetry in German shepherd dogs.

Pelvimetry was performed on a computed tomographic scanner using dorsal and lateral scout-view images of 10 adult German shepherd dogs. The vertical and transverse diameters of the pelvis were measured and the pelvic inlet and pelvic outlet areas were also calculated. No significant correlations between the pelvic measurements and body weight, age and sex were found. Although the conjugata vera, diameter verticalis, diameter sacralis, sagittal diameter and the distance between the two medial tubera ischiadica were longer in females, no significant statistical difference was found between male and female animals for all measurements. It is proposed that the computed tomographic pelvimetry should be preferred for the sensitive measurements when the normal standards are determined for different animal species and the cost is reduced to an acceptable level.

Computed tomographic measurements of the trachea in dog.

Computed tomographic examination of the trachea was performed on 18 mix-breed dogs. The measurements were taken from 5 segments from which the first 3 segments were extrathoracic trachea, 1 segment at the level of thoracic inlet and 1 segment intrathoracic trachea. The inner and outer transverse and vertical diameters were measured at each of the segments. The cross-sectional area of the lumen, ratio of the inner and outer transverse and vertical diameters were also calculated. It was seen that the diameters and cross-sectional area of the lumen decreased gradually in the extrathoracic trachea from larynx to thoracic inlet but these values showed an increase in the intrathoracic trachea. Correlation coefficients between the inner diameters, cross-sectional lumen areas and the body weight was calculated and a high correlation was found between the inner transverse and vertical diameters and the cross-sectional area of the lumen except between the inner transverse and vertical diameters at the level of S5 segment.

A quantitative study on the trachea of the dog.

This study was carried out to record the detailed morphometric structure of the trachea in dogs using 15 female and four male healthy adult mongrel dogs. The diameter and thickness of each tracheal ring were measured, the number of tracheal rings varying from 36 to 45. All data were subjected to statistical analysis which was carried out on individual sections of the trachea, i.e. the cranial cervical, middle cervical, thoracic inlet and the intrathoracic tracheal regions, which consisted of 12, 12, nine and 12 tracheal rings, respectively. Fusion of the tracheal rings was especially obvious in the cranial cervical and thoracic inlet regions as a result of neck movements. The diameter and thickness of the tracheal rings are smallest at the thoracic inlet level because the direction of the trachea changes at this point where the thoracic inlet is relatively small and surrounded by bone. The ratios of inner transverse to inner vertical and outer transverse to outer vertical diameters were almost the same, between 1.14 and 1.25 in all regions, which indicated that the trachea is near-circular in shape in the dog. At the thoracic inlet level cross-sectional lumen areas are 7 and 6% smaller than those in the middle cervical and intrathoracic regions, respectively. The thinnest cartilage was seen at the thoracic inlet level where there is a risk of tracheal collapse.

A quantitative study of the circulus arteriosus cerebri of the camel (Camelus dromedarius).

The afferent vessels of the circulus arteriosus cerebri in the camel were studied quantitatively. It was found that the diameters of the arteries did not differ significantly on the left and right sides. An interesting observation was that the basilar artery contributed to the blood supply of the brain in the camel, in contrast to the situation in other ruminants.

A quantitative study on the retial arteries in one-humped camels.

The brain arteries of camels were injected with latex and the rostral epidural rete mirabile, which is situated inside the cavernous sinus at the base of the brain, was studied both grossly and quantitatively. The rostral epidural rete mirabile is formed by the retial branches of the maxillary and external ophthalmic arteries and also the internal carotid artery. When the ratio of the blood supply to the rete was estimated from the diameter of each vessel, it was found that the branches of the maxillary artery carried 76.41%, the branches of the external ophthalmic artery carried 10.26% and the internal carotid artery carried 13.33%.

Anatomical factors in displacement of the superficial digital flexor tendon in dogs.

The superficial digital flexor muscles of 12 adult dogs were investigated to get informations on the possible anatomical factors which could play a role in the displacement of the superficial digital flexor tendon in dogs. It was seen that the lateral displacement of the superficial digital flexor tendon, tearing its medial attachment, was a result of the weaker medial attachment on the tuber calcanei and the change of the angulation between the calcaneus, insertion and origin points of the muscle in flexed hind limb.