We were interested in the vignette by Iraci et al1 in the February 1993 issue of the Archives. The authors mention the traumatic origin of this form of digital fibromatosis in otherwise healthy young male patients. We have seen similar findings in another patient and thereby confirm this possible pathogenetic mechanism.
Report of a Case.
A 12-year-old otherwise healthy boy presented with a 1-year history of asymptomatic swelling of the proximal interphalangeal joints of the index, middle, and ring fingers of both hands. There was no family history, and the roentgenogram of his hands showed no bony abnormality. During physical examination, the boy repeatedly clasped his hands and rubbed his crossed fingers in a striking manner.
We agree that these peculiar lesions are probably exclusively caused by repetitive mechanical stimuli. With this ritualistic behavior (ticlike habit) in our patient, the friction was highest on the index, middle, and