Corns are often seen in athletes and in patient populations exposed to uneven friction from footwear or gait abnormalities, including elderly persons, diabetic patients, an. Knuckle pads may be idiopathic; however, they are often of the pseudo-knuckle pad variety and related to repetitive trauma . Predisoposing work-related trauma with repeated motions or rubbing of the PIP joints or knuckles, as seen in live-chicken hangers in a poultry processing plant, [] has been reported.