You are correct. Reticulated telangiectasia, hyperpigmentation, and ulceration are characteristics of erythema ab igne. On questioning, he admitted to spending long periods in front of an open fire to alleviate his knee pain. Removal of the heat source is usually sufficient to resolve the rash. In cases where ulceration persists despite removal of the heat source, further investigation is warranted to rule out a Marjolin-type ulcer (malignant change in an area of chronic ulceration).