You are looking at 1 - 3 of 3 items for
- Author or Editor: Sabine M. Breit x
- Refine by Access: All Content x
Objective—To determine the ratio of ventral-to-dorsal transverse diameters between the wings of the sacrum on ventrodorsal radiographic views of the pelvis in large dogs and to validate the reliability of this morphometric analysis for functional interpretation.
Sample Population—Pelvic specimens from 40 large-breed dogs and radiographs of 113 large-breed dogs.
Procedure—In an anatomic and radiographic evaluation, the transverse dorsal diameter (TVDS) and transverse ventral diameter (TVV) between the wings of the sacrum were evaluated in sacrum specimens and on corresponding radiographs of the pelvis and sacrum. The ratio between TVV and TVDS (VD ratio) was calculated. Intraobserver reliability was determined by calculation of the coefficient of variation. In a retrospective radiographic evaluation, the VD ratio was determined in Rottweilers, Golden Retrievers, and German Shepherd Dogs. Correlations between VD ratio and breed, age, and sex were tested.
Results—The VD ratio was significantly higher in Rottweilers than in Golden Retrievers and German Shepherd Dogs, denoting an oblique alignment of the sacral wings in Rottweilers (ie, the dorsal aspects of the sacral wings were located more medially than the ventral aspects) and an almost sagittal alignment in the other breeds. The VD ratio was significantly associated with age but not with sex.
Conclusion and Clinical Relevance—Sagittal alignment of the wings of the sacrum is considered to be biomechanically less efficient. These results provide a basis for further studies to evaluate radiographic assessment of the sacroiliac joints similar to the evaluation for hip dysplasia. (Am J Vet Res 2002; 63:1220–1225)
Objective—To assess joint geometry and highlight potential evidence of physiologic incongruity in cubital (elbow) joints of large, small, and chondrodystrophic breeds of dogs.
Sample Population—Nonarthritic elbow joints obtained from cadavers of mature dogs of large breeds (n = 19), small breeds (14), or chondrodystrophic breeds (8).
Procedure—Magnetic resonance imaging was used to quantify interosseous gaps at 6 defined positions and 2 sagittal planes of the humeroantebrachial region by use of a fat-suppressed 3-dimensional gradient-echo sequence.
Results—Interosseous gaps in the more medially located sagittal plane were significantly narrower at the level of the anconeal process than at any other position of the joint in large-breed dogs, compared with results for small- or chondrodystrophic-breed dogs. In both sagittal planes, the gaps were significantly wider at the center of the ulnar trochlear notch than at any other position. Significant correlation between body weight and width of the interosseous gaps was found only in large-breed dogs and was found in both sagittal planes at the center of the ulnar trochlear notch (r, 0.834 and r, 0.680, respectively).
Conclusions and Clinical Relevance—In large-breed dogs, the interosseous gap was especially narrow at the level of the anconeal process and its diametric position. This suggests less ability to compensate intra-articular steps in dogs with short ulna syndrome, which predisposes to failure of the union between the anconeal process and olecranon. Geometric incongruity may be regarded as clinically normal in nonarthritic humeroulnar joints. The degree of geometric incongruity increases with body weight.
Objective—To compare bone mineral measurements obtained by use of dual-energy x-ray absorptiometry (DEXA), peripheral quantitative computed tomography (pQCT), and chemical-physical analyses and determine effects of age and femur size on values obtained for the various techniques.
Sample Population—Femurs obtained from 15 juvenile and 15 adult large-breed dogs.
Procedure—In each femur, 7 regions of interest were examined by use of DEXA to measure the bone mineral content (BMC) and bone mineral density (BMD), and 5 were examined by use of pQCT to measure BMD. Among these, 1 region was examined by both noninvasive methods and an invasive method. Volume of the femur was determined by water displacement. Volumetric bone density (VBD) was calculated. Calcium (Ca), phosphorus (P), total Ca, and total P contents were determined.
Results—DEXA- and pQCT-derived results revealed that all values increased with age in juvenile dogs. In adults, VBD and pQCT-derived BMD decreased significantly and DEXA-derived BMD increased with increasing femur length. The pQCT-derived BMD correlated well with VBD and Ca content, whereas DEXA-derived BMC was strongly correlated with Ca content. In juveniles, values correlated regardless of the technique used, whereas in adult dogs, DEXA-derived BMD did not correlate with pQCT-derived BMD, Ca concentration, or VBD unless data were adjusted on the basis of femur length.
Conclusions and Clinical Relevance—DEXA-derived BMD adjusted for femur length yields approximately the same percentage variability in VBD as for pQCT-derived BMD. However, pQCT-derived BMD is still more sensitive for determining variability in Ca concentration, compared with DEXA-derived BMD adjusted for femur length. (Am J Vet Res 2004;65:891–900)