Digital clubbing is characterized by bulbous fusiform enlargement of the distal portion of a digit with loss of the angle between the proximal nail fold and the nail plate (Lovibond angle). The mechanism underlying clubbing is not known. It is associated with multiple medical conditions including carcinoma, intrathoracic sepsis, bacterial endocarditis, cyanotic congenital heart disease, esophageal disorders, cirrhosis, inflammatory bowel disease, pulmonary disorders, atrial myxoma, multiple pregnancies, and pachydermoperiostosis. The incidence of clubbing with each of these conditions is variable. It may be reversible in certain disease processes.
Management and Disposition
Treatment of the underlying condition is indicated.
Clubbing. Marked digital clubbing can be seen in this patient. Note the hyperemia in the skin folds around the nail. (Photo contributor: Alan B. Storrow, MD.)
Clubbing. Pronounced digital clubbing. Note the loss of angle between the proximal nail fold and the nail plate (Lovibond angle). (Photo contributor: Robert Tubbs, MD.)
Patients rarely recognize clubbing in their own fingers even if the condition is marked.
Pseudoclubbing is an overcurvature of the nails in both longitudinal and transverse axes, with preservation of the angle between the proximal nail fold and nail plate.