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Ninety-four flat panel catheter angiotomography acquisitions obtained during the selective injection of intersegmental arteries providing an anterior radiculomedullary artery were reviewed. The location of radicular arteries could be ascertained in 78/94 flat panel catheter angiotomography acquisitions. Fifty-three acquisitions (67.9%) were on the left side, and 25 (32.1%), on the right, between T2 and L3. The arteries were found in the anterosuperior quadrant in 75 cases (96.2%), in the posterosuperior quadrant in 2 (2.6%), and in the anteroinferior quadrant in 1(1.3%). Needle placement in the anterosuperior quadrant (subpedicular approach) should be avoided during transforaminal epidural steroid injection. The authors advocate the posterolateral approach that allows placing the needle tip away from the documented position of ARMA contributors within the neural foramen, reducing the risk of intra-arterial injection or injury to the spinal vascularization.