Blood supply of the articular disc of the antebrachiocarpal joint in dogs.

The normal vascular anatomy of the articular disc of 48 antebrachiocarpal joints was studied in 24 dogs (12 puppies and 12 adult animals) using an India ink vascular injection technique. It was found that the articular disc receives its blood supply mainly from the palmar and dorsal branches of the palmar interosseous artery. Branches of these 2 arteries arborise and give direct peridiscal vessels to the dorsal, proximal and palmar sides of the articular disc. The peridiscal vessels ramify and anastomose with one another to form a cup-shaped terminal peridiscal capillary plexus around the disc which ends at the peripheral parts of the disc in a series of terminal capillary loops. This leaves the major central segment of the disc without blood vessels. The proportion of vascularised to nonvascularised areas of the disc depends upon the age of the animals. In young puppies, the degree of vascular penetration into the disc is quite extensive, while in adult animals it ranges from 15 to 25% of the discal width; the considerably larger central area of the articular disc is thus avascular.