Ischemia of the motoneurons in the anterior horn is a well known pathological entity. Their clinical signs and symptoms are similar to those of amyotrophic lateral sclerosis. Evidence by selective angiography of angiomas of the spinal cord or compression or deviation of Adamkiewicz artery may be suggestive of an initial vascular lesion. Various data (knowledge of development or lesions during experimental ischemia, selective electrophysiologic analysis of anterior horn neurons, evidence of precise circumstances of spinal vascular disorder or spinal arteriography) suggest that anterior horn ischemia is a multiple aspect phenomenon. Our 4 cases illustrate this hypothesis and demonstrate under confirmed vascular circumstances the different clinical aspects of anterior horn ischemic lesions. In addition to typical amyotrophic paralysis unusual or misleading symptoms may occur such as claudication, paroxysmal contractures or progressive spastic paraparesis. Investigations required and possible treatment of the lesions are simplified by awareness of these various clinical aspects.