Simple digital clubbing: Characteristic bone scan appearance

Clubbing is a well-recognized entity that heralds intrathoracic disease. Clinically, characteristic soft tissue changes involve both the fingers and toes, most often together. Although clubbing may be an isolated finding, as in the case presented here, the syndrome of hypertrophic pulmonary osteoarthropathy (HPO) includes clubbing, hypertrophy of the upper and lower extremities, joint pain and swelling, neurovascular disturbances, and bilateral proliferative periostitis. While HPO is almost always related to chest malignancy, simple clubbing, which may progress to HPO, is associated with malignant tumors in only 15-20% of cases. The scintigraphic appearance of digital clubbing is characteristic and distinctive from the pericortical pattern of HPO.