Degeneration of the atrioventricular valves renders the leaflets thicker and irregular, leading to insufficient
coaptation of the leaflets and regurgitation of blood with accompanying enlargement of the atria and ventricles.
The thickening of the leaflets and consequent
inadequate coaptation result in mitral valve insufficiency, with regurgitation into the left atrium (LA) during systole.
External coaptation is unsuitable for use in fractures where bending and rotational forces of high magnitude (such as in large breed or very active dogs) are expected.
External
coaptation is also unsuitable in comminuted fractures or in long oblique fractures as it can not prevent collapse and overriding of the fracture fragments.
Unfortunately, if your dog's luxation has been diagnosed as a Grade 3 - 4 luxation, an external
coaptation, such as an OrthoPets dog knee brace will not be able to achieve adequate tibial alignment nor would the patient tolerate the extreme twisting force needed to keep the knee cap in alignment.