Also called ?nger-sucking, this is a universal and harmless habit in infancy. It is usually given up gradually during the pre-school period, but quite often persists after school age – especially if the child is tired, lonely or unhappy. In these cases the remedy is to deal with the cause. It is cruel to use threats or punishment to try to stop the habit.... thumb-sucking
(gamekeeper’s thumb) an injury to the ulnar collateral ligament of the thumb, caused by forced abduction across the metacarpophalangeal joint, at the base of the thumb. Treatment is by splintage or, in the case of severe injuries, by surgical repair of the torn ligament ends.... skier’s thumb