Abstract
Based on most neuroanatomical descriptions, the anterior spinal artery (ASA) originates from two small vessels of the vertebral arteries, which are anastomosed just before forming the basilar artery. This study aimed to determine and quantify the possible variants of the origin of the ASA and its trajectory in samples of human brain stems. Male brain stems with the superior portion of the spinal cord until myelomera C3 of 23 adult human, and no evident morphological alterations were selected. The brain stems were collected for three years and fixed in a 10% formalin solution at the Anatomy Laboratory of the Universidad de Caldas (Colombia). Five samples (21.7%) had variations in the origin and trajectory of the anterior spinal artery. The variations in the origin of the ASA could generate morphofunctional advantages instead of leading to complications. That is the case when there are two anterior spinal arteries since it would increase tissue perfusion, thus protecting part of the spinal cord from ischemic pathologies. It is essential to consider the variations that may exist in the supply of the anterior region of the spinal cord for clinical and surgical assessments due to variations in its supplied territory.