Pterigio inverso delle unghie

Four new cases of 'pterygium inversum unguis' are described. These diseases differ in clinical and histopathologic aspects of the primitive and congenital pterygium and of the secondary pterygium as well from the undernail hyperkeratosis. The process peculiarity which strikes only the female sex is confirmed; it begins in a latent form and goes on with symptomatology which consists essentially in aching whenever the nails are cut.