Morton's mark

Important diagnostic sign in lymphedema: Oedematous swelling of the back of the toes with transverse skin folds over the metatarsophalangeal joints of the toes.

• The Stemmer's sign is positive if the skin fold is widened over the back of the toe (check the 2nd toe) or the back of the finger (> 4), or is difficult or impossible to lift off. The Stemmer's sign can be false negative, especially in secondary lymphedema, which extends from the root of the limb from proximal to distal.
• In lymphedema, the clinical phenomenon that the natural skin folds at the transition from the toes to the back of the foot or from the back of the foot to the lower leg are deepened can be distinguished from Stemmer's sign.

According to Pannier et al (2007), different degrees of the Stemmers sign can be distinguished:

• Grade 0: normal skin fold
• Grade 1: thickened skin fold, between 0,5 and 1,0cm
• Grade 2: thickened skin fold > 1,0cm
• Grade 3: thickened skin fold > 1,0cm + pronounced induration and/or papillomatosis of the skin

1. Pannier F et al (2007) Prevalence of the stemmer sign in the average adult population. Results of the Bonn Vein Study. Phlebology 36: 289-292