Pachydermodactyly (PDD) is a benign, asymptomatic soft tissue swelling affecting the skin of the lateral aspects of the proximal interphalangeal joints of the fingers II-IV, mostly in young adolescent males, and could be interpreted as a consequence of tic-like behaviour as an obsessive-compulsive disorder in male adolescents. The differential diagnosis includes numerous diseases; a rapid clinical recognition of PDD would avoid many useless and expensive diagnostic tests. There is no effective medical treatment for PDD, but discontinuation of the tic-like mechanical traumatisation generally leads to a marked amelioration of the finger swelling. In this article we review the world literature, which contains 87 additional cases on this topic.