Callosities of other sites (Q93012)

Callosities located other than on the hands and feet. They may arise as the result of friction from appliances (e.g. trusses, calipers, prostheses) or from often repeated minor frictional trauma as, for instance, over the ischial tuberosities in cyclists or, in devout Muslims, on the central forehead from repeatedly touching the head on a prayer stone (prayer nodules).