A 66-year-old white man presented with a solitary subcutaneous nodule on the dorsum of his left hand (Figure 1). The nodule had gradually enlarged over the past 2 years and had become quite tender to the touch. The patient recalled no preceding trauma or infection at the site. The nodule, which was located in the first dorsal web space, measured approximately 12 mm in diameter, was well demarcated, round, slightly compressible, and somewhat mobile under the skin surface. The overlying skin was intact, with a faint blue hue. A skin examination did not reveal any other abnormalities. The nodule was removed and examined microscopically (Figure 2).
Rao J, Goldman MP. A Painful Blue Nodule on the Dorsum of the Hand—Quiz Case. Arch Dermatol. 2004;140(11):1393-1398. doi:10.1001/archderm.140.11.1393-g