Thumb Sprain

While a bone can fracture or break, a sprain results from an injured ligament. Ligaments connect bones across joints.

Causes of Thumb Sprains

Thumb sprains occur the thumb is jammed and bent in an unnatural, extreme position. For example, many individuals sprain their thumbs when they hit against another player, the ground, or ball during a sporting event. After the injury, the thumb will usually swell, show signs of bruising, and hurt when it is moved.

Common Causes

The ligament most often injured is the ulnar collateral ligament. Because that ligament is often injured in skiing accidents, the injury is sometimes referred to as "skier's thumb." The injury often results when a skier falls and the pole bends the thumb back unnaturally.

The ligament can also be injured if the thumb is jammed into the ground during a fall, or into another player or ball during athletic activities. Although it isn't injured as often, the radial collateral ligament is also subject to injury.

Diagnosis & Treatment

An x-ray will usually be taken to determine whether any bones have broken. Your hand surgeon will also examine your thumb to see if the ligament is torn. A cast or splint will be used to hold the ligament in place so as to facilitate healing if it was partially torn, or if the radial collateral ligaments were injured.

If the ulnar collateral ligament was completely torn, the torn end usually ends up stuck behind a tendon. Tears to that ligament usually require surgery, and what remains of the ligament may need to be reconstructed.

Explanation of the Injury

When an old injury lasts for several weeks, it's referred to as chronic. These conditions usually result in pain, especially when utilized for pinching purposes, and the thumb joint may be unstable and weak in strength. Such injuries can be treated by having the ligaments surgically reconstructed, or by fusing the joint if arthritis has developed.

Concerns of a Sprained Thumb

Whenever the thumb has been jammed hard enough to injure a ligament, the possibility of a broken bone is a real concern. To fix a fracture, your hand surgeon may use metal screws, pins, or plates to hold the fractured bone together and this may require a separate surgery. X-rays won't show any damage to the cartilage, which may cause arthritis. Surgery or injections of cortisone to treat that condition may be needed at a later time.