surfer’s nodules

surfer’s nodules [ME, suffe, rush; L, nodus, knot] , nodules on the skin of the knees, ankles, feet, or toes of a surfer caused by repeated contact of the skin with an abrasive, sandy surfboard. The nodules slowly diminish in size and disappear if surfing is discontinued. When treatment is necessary, injection of corticosteroids is usually effective.