[The pincer-nail syndrome--a rare differential diagnosis of finger end joint-/nail involvement].

A 55-year-old patient who clinically presented with a Heberden arthrosis and gryphosis of the second and fourth finger nails of the left hand was admitted to our outpatient department under the tentative diagnosis of psoriatic arthritis. Nature of nail damage and combination of clinical findings suggested the diagnosis of a pincer-nail syndrome. The pathogenesis of this rare disease is not yet clear. Its complete clinical picture includes gryphosis of finger and toe nails in combination with acroosteolytic shortening of the end-phalanx and destructive arthrosis of the terminal joints of toes and fingers. Since deformation of the nail, which sometimes includes inflammation of the nail bed, may cause marked pain, surgical intervention with excision of the nail and, if necessary, revision of the nail bed has to be performed in most cases.