Epidemiological and structural findings supporting the fibromatous origin of dorsal knuckle pads.

Epidemiological, optical and electron microscopical findings suggest that dorsal knuckle pads and Dupuytren's disease are fibrosing disorders with common features. In all cases examined, knuckle pads were always associated with Dupuytren's contracture and, in a significant number of cases, with bilateral Dupuytren's contracture. In a statistically significant number of patients with knuckle pads, Ledderhose's and Peyronie's diseases were also present (P less than 0.001). Optical and electron microscopical studies showed that cell types and extracellular matrix were identical in knuckle pads and Dupuytren's nodules in different patients.