|Throughout the literature survey we tried to present and explain why the radiological and clinical examination of the canine hip joints frequently do not coincide and agree. The genetic polymorphism and involvement of the several environmental etiological factors make the Canine Hip Dysplasia (CHD) to have an onset at variable age depending on the breed and in excess presence of the various environmental factors.
The complexity of interactions of the etiological factors leads to the development of various quantification and prediction models. Radiographic measurements and scoring systems that have a common aim: To include or exclude a dog in breading having CHD based on a scoring scale and thus provide measure means for comparing dogs of within the same or different breed and assessing their appropriateness for reproduction of a CHD ―free offspring.
In our experimental work by employing a simple statistical method we proven that the quality of X-ray film picture taken is of paramount importance. Moreover, utilization and digitalization of X-ray films and the use of image software such as DP-Scale® proves to be valuable. The use of image software can help in averting errors in measurements and can create a more user-friendly environment for the operator than the routine task of manually marking and drawing lines upon hip joint X-ray films. Errors frequently occur during the traditional mode ( e.g. The use of markers with variable diameters, using different instruments for measure of the circumference of the femoral head), are well avoided by using the DP-Scale®. Finally, we believe, an interesting result from our work is that the DP-Scale is very much dependent on the quality and the magnification of the digitally processed X-ray films. From our work appears that radiographic films either digitalized ―as they are -(i.e. without magnification or zooming) or highly magnified provide unclear skylines, thus less reliable results when measuring with DP-Scale®. These values are, however, still within comparable range to the manually performed measurements made by the experienced veterinary professionals the traditional way. Our recommendation is that DP-Scale® can be highly accurate, precise and reliable tool in measuring the Norberg angle when the imported digital image is moderately magnified . In the ―medium‖ magnification, the screen pixels feel to be clearer and the fine details of ridges and bony borders are easier to identify. At this setting, we believe DP-Scale® proves to be very reliable, easier to operate with less dilemma in finding the right demarcation spots upon the image. It should not be difficult to repeat the measuring-procedure (by different examiners or at different times). A further advantage of DP-Scale ® is the simple way of forwarding the digitalized X-rays – with and without the indication of the Norberg Angle - thus making (inter)national correspondence among veterinarians and dog breeders much more efficient.