Pachydermodactyly: four additional cases.

Pachydermodactyly (PDD) is a rare, benign form of digital fibromatosis characterized by an asymptomatic soft tissue swelling affecting the skin of the lateral aspects of the proximal interphalangeal joints of the fingers, and it sometimes can be misdiagnosed with some rheumatic condition. Recognition on these features should lead to its more frequent diagnosis. The purpose of our study is to report four additional cases of PDD and discuss the differential diagnosis.