palmar carpal arch palmar carpal arch the palmar carpal arch is a joining of an artery to an artery, a circulatory anastomosis, known as an arterio-arterial anastomosis. the two connected arteries are the palmar carpal branch of the radial artery and the palmar carpal branch of the ulnar artery. palmar carpal archdeep view of ulnar and radial arteries (palmar carpal arch visible at level of "volar radial carpal" and "volar ulnar carpal", but not labeled)detailssourcepalmar carpal branch of radial artery and palmar carpal branch of ulnar arteryanatomical terminology this anastomosis is joined by a branch from the anterior interosseous artery above, and by recurrent branches from the deep palmar arch below, thus forming a palmar carpal network which supplies the articulations of the wrist and carpus.