Circumscribed thickening of the skin over the metacarpophalangeal and interphalangeal articulations was first described by Garrod, who reported 3 cases in 18931 and 12 cases in 1904.2 Since then, infrequent references have appeared in dermatologic literature and this entity is discussed in only one available textbook on dermatology.3 The affliction is probably not unusual but has lacked attention because it is rarely a presenting complaint by the patient and escapes notice in routine dermatologic examinations. This article will present 30 patients manifesting this dermatosis and will primarily discuss etiologic factors.
Unfortunately, in the literature, thickenings over the finger and knuckle articulations have been called "knuckle pads," giving the impression that only the knuckles are involved. This is not true, as will be shown, because many appear over the finger joints; in fact, the proximal phalangeal joints are most frequently involved. A more accurate clinical