In 1993 Angrigiani raised the question as to whether the distal part of the posterior interosseous artery (AIP) is a recurrent branch of the anterior interosseous artery (AIA) and forms a "choke"--anastomosis with the AIP in the middle of the forearm. A dissection study was conducted on 66 upper extremities to evaluate the diameters of the dorsal branch of the anterior interosseous artery, the anastomotic branch, the diameter of the posterior interosseous artery at the point of origin of the septocutaneous perforators in the middle of the forearm and the diameter of the posterior interosseous artery at the point of emergence in the dorsal compartment. We further tried to identify different forms and types of the "distal" anastomosis and the connections to the dorsal carpal arch and the ulnar artery. A distal anastomosis between the AIA and AIP was found in 65 of the 66 upper extremities. Three different types of anastomosis could be identified. The smallest diameter was found at the middle of the forearm (mean diameter AIA 1.28 mm; anastomotic branch 0.6 mm; AIP at the middle of the forearm 0.39 mm; AIP prox. 1.35 mm). A branch through the fifth extensor compartment was present in all of our specimens (mean diameter 0.54 mm). A branch through the forth extensor compartment could be found in 16 specimens. Based on our findings and the embryological development, we conclude that the AIP is only present in the proximal half of the forearm. In the distal part, the dorsal branch of the anterior interosseous artery forms a vascular arcade, which gives off branches to the dorsal carpal arch, the ulnar head and the ulnar artery. This arcade anastomoses with the posterior interosseous artery in the middle of the forearm by means of a choke anastomosis. We also conclude that the term "recurrent branch of the anterior interosseous artery" for the distal part of posterior interosseous artery is correct.