injuries and poisoning
Thumb Sprains
Introduction
Thumb sprains are tears in the ligaments that attach the thumb to the hand. When the thumb is sprained, people have difficulty grasping objects between their thumb and index finger, and the thumb is painful and swollen. Doctors diagnose a thumb sprain by examining the thumb, sometimes after giving the person an anesthetic to make the examination less painful. Most thumb sprains are immobilized with a thumb spica splint, but sometimes surgery is needed. (See also Overview of Sprains and Other Soft-Tissue Injuries .) Most thumb sprains involve the main ligament at the base of the thumb on the inside of the hand. This ligament is often sprained when people fall on their hand while holding a ski pole. Thus, this injury is often called skier's thumb. This ligament may also be injured by jamming the thumb backward on a hard surface when falling or on a ball as when catching a baseball. Repeated overstretching of the joint can also tear the ligament, as occurred in English gamekeepers, who broke the necks of rabbits with their hands. Thus, this injury is sometimes called gamekeeper's thumb. Sometimes when the ligament tears, it pulls a small piece of bone from the bottom of the thumb bone (called an avulsion fracture). 