To assess the association between dorsal midline skin discolorations, tethering of the spinal cord, and the role of ultrasound screening of these stigmata, focusing specifically on vascular lesions. We conducted a prospective observational study of infants <6 months of age with suspicious dorsal midline skin stigmata. All were evaluated by physical examination and ultrasound scan. A subset also had a magnetic resonance imaging examination. We examined the association between small, red-shaded discolorations and their respective imaging findings. Among 100 cases with discolorations of vascular types, either isolated or combined with low-risk simple dimples or deviated gluteal folds, none had clinically significant pathologic findings requiring surgical intervention. Midline lumbar discolorations are more benign than previously thought. Despite the very low association of this group of stigmata with surgical implications, we still recommend the routine use of ultrasound scanning.