Forty to fifty percent of critical limb ischemia patients have infrainguinal chronic total occlusions, frequently below-the-knee. With probabilities ranging from 21 to 90%, the Infrapop-CTO Score presented here in CCI predicts the likelihood of anterograde crossing of infrapopliteal chronic total occlusions (CTO). Based on cap morphology, occlusion length, calcification, and restenosis status, the score is easily assessed in the lab. An unfavorable Infrapop-CTO Score of 5 or 6, particularly coupled with convex proximal and distal caps (chronic total occlusion plaque [CTOP] Type IV), portends very low (21%) probability of successful anterograde crossing. An initial retrograde crossing strategy should be considered in these patients when technically feasible, followed by combined anterograde-retrograde intervention.