<unk>  usually involves highly localized lichenification, mild hyperpigmentation, and erythema where the chin rest or instrument body presses against the skin of the<unk> . Other signs and symptoms include scale buildup, cyst and scar formation, papules and pustules related to local infection, and focal edema. In Blum & Ritter's study in West Germany (1990), they found that 27% of their population had only minor issues, 72% had a palpable mass at the site, and 23% reported pain and other signs of inflammation such as hyperthermia, pulsation, and cystic, pustular, or papular lesions. Size of masses were an average of 2 cm in diameter ranging up to 4 cm, some being associated with purulent drainage, continuous discharge, and crusting. Dystrophic calcinosis cutis has also been reported. Other serious sequelae include sialolithiasis of the submandibular gland and adenolymphoma of the parotid gland. The histopathology of<unk>  frequently shows hyperkeratosis and acanthosis, along with plugging of follicles. Histiocytic infiltration with granulomas to foreign body and follicular cysts are also common. Foreign body granulomas are thought to derive from abrasion of the wooden surface of the chin rest and its absorption into the superficial dermis. The location and complex mechanism of causation for<unk>  give rise to a wider spectrum of skin changes when compared to contact dermatitis from more common irritants.<unk>  can be differentiated from rosacea and sarcoid reaction with granulomas.
Fiddler's neck
Cradle cap
Golfer's elbow
Barrel chest
Maddox wing
Saber shin
Burn center
Cramp-ring