The author of the present study examined electric activity of the muscle in three types of chronic arterial occlusions, i.e. in obliterating atherosclerosis, obliterating thromboangiitis and diabetic angiopathy. He obtained two different electromyographic patterns. One, present in patients suffering from obliterating atherosclerosis, showed signs of a peripheral nerve-damage (characterized by broad action-potentials) and another, found in patients with obliterating thromboangiitis and in diabetics suffering from diabetic angiopathy, with a pattern corresponding to a combined injury--of impaired muscle-fibre and peripheral nerve (characterized by pathological action-potentials of short and long duration). The last group could be further divided into a subgroup where both electromyographic lesions were distinctly noted, comprising patients with obliterating thromboangiitis, and another subgroup, clearly characterized by primary myogenic disorder with a milder disturbance of peripheral nerves. The last subgroup consisted of diabetic patients suffering from diabetic angiopathy. According to the author's suggestion, the divergence in electromyographic patterns in individual diseases of peripheral arteries may be conditioned by different in individual diseases of peripheral arteries, may be conditioned by different localisations of arterial occlusions. Various preferential levels of arterial occlusions give to various diseases a different clinical, as well as electromyographical feature. Neurogenic findings in obliterating atherosclerosis is determined by occlusions of large arteries. From these vessels afferent branches divert for the nutritive supply of the nerve-trunk of the leg. This results in ischaemic lesions of nervous fibers of various degrees in the leg. In the periphery a total of fine or gross changes may be registered on the electomyogram--as a sign of a peripheral nervous lesion. Electromyographic pattern of obliterating thromboangiitis reveals changes similar to those of obliterating atherosclerosis--namely a picture of a peripheral nervous lesion--but in addition there appear regular changes indicating a primarilly muscle impairment. The interpretation means that nervous impairment is present. In fact, no occlusions of the main arteries take place at the level of the diverted nutrient branches of the nerve-trunk, but obliterating thromboangiitis, affecting small and medium vessels, presses the occlusions more proximally to the nervous trunk. The final result and effect is the same and in more severe instances even more striking. Nutrient muscle-arteries, being vessels of medium caliber, are obturated--in cases of obliterating thromboangiitis--commonly with main trunks in the tibial and foot-zone. Possibilities of a collateral circulation in instances where medium and small arteries are obturated, are worse than in large artery-occlusions and the blood-flow becomes more impaired. Realizing the adjacent diffuse affection of arteriolar muscle-net, we get a picture described by Scalabrino and Bianchi...