Sports-related pads.
Knuckle pads, first described by Garrod in 1893, 1 are benign, asymptomatic, well- circumscribed, smooth, firm, skin colored papules, nodules, or plaques. They most commonly occur on the dorsal aspect of the proximal interphalangeal joint of the finger, 2 but also may occur on the dorsal aspects of the foot over joints. 3-5 Knuckle pads may be inherited or acquired. 1 While some authors suggest that trauma is not a significant factor, 6 acquired knuckle pads have been associated with repetitive friction and trauma, 2,7 and may resemble athlete's nodules (also referred to as collagenomas). 1 Histologically, knuckle pads are characterized by hyperkeratosis, hypergranulosis, proliferation of fibroblasts and capillaries, and thickened and irregular collagen bundles. 1 Few cases of knuckle pads involving the lower extremities have been reported. 7 Knuckle pads of the feet have been described in association with inherited syndromes, such as acrokeratoelastoidosis Costa, 3 a syndrome of knuckle pads, leukonychia and deafness, 4 and a syndrome of knuckle pads, leukonychia, deafness and keratosis palmoplantaris. 5 We report a case that illustrates an unusual presentation of acquired knuckle pads of the feet secondary to repetitive friction from athletic gear.
Dickens
Rio
R
Department of Dermatology, College of Medicine, University of Cincinnati, Ohio 45267-0592, USA.
Adams
Brian B
BB
Mutasim
Diya F
DF
D000293:Adolescent; D005260:Female; D005533:Foot Dermatoses / Q000209:etiology* / Q000473:pathology*; D006801:Humans; D007642:Keratosis / Q000209:etiology* / Q000473:pathology*; D011482:Protective Devices / Q000009:adverse effects*; D019876:Sports Equipment / Q000009:adverse effects*