Ulnar Collateral Ligament Injuries of the Thumb: Symptoms and Treatment

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A gamekeeper's thumb, also called a skier's thumb, is an injury to one of the important ligaments at the base of the thumb joint. The injury involves the ulnar collateral ligament (UCL) of the thumb.

The UCL is a band of tough, fibrous tissue that connects the bones at the base of the thumb. This ligament prevents the thumb from pointing too far away from the hand. An injury to the ulnar collateral ligament occurs when this structure is stretched too far.

A skier falling on the side of a mountain
Bob Winsett / Getty Images

Types of UCL Injury

The two common descriptive terms for injuries to the ulnar collateral ligament are:

  • Skier's thumb
  • Gamekeeper's thumb

These names are often used interchangeably, although they describe slightly different types of injury.

Skier's Thumb: Acute UCL Injury

A skier's thumb injury is described as an acute injury to the ulnar collateral ligament. When a skier falls with his or her hand caught in a ski pole, the thumb can be bent away from the hand. Because of the shape of the ski pole, the thumb tends to get caught and significant stresses are placed on the ulnar collateral ligament. If the thumb is bent far enough, the ulnar collateral ligament will tear.

While there are many ways to injure the ulnar collateral ligament, a skier's thumb is the term used for an acute injury to the ligament.

Gamekeeper's Thumb: Chronic Injury to the UCL

The other injury is called a gamekeeper's thumb; this refers to a more chronic pattern of injury that leads to loosening of the ulnar ligament over time. The name comes from the European gamekeepers who would kill their game by grasping the head of the animal between their thumb and index finger to break its neck. Over time, the thumb loosens and the ulnar collateral ligament is stretched, eventually causing problems.

Gamekeeper's thumb is the term used to describe chronic injuries to the ulnar collateral ligament.


An ulnar collateral ligament injury most often occurs as a result of sports injuries. Athletes who are skiers and soccer players often sustain this injury. An ulnar collateral ligament injury can also occur as the result of a fall or other trauma.

Patients who sustain an acute tear of the ulnar collateral ligament typically complain of pain and swelling directly over the torn ligament at the base of the thumb. Patients will often have a difficult time grasping objects or holding objects firmly in their grip. Because this injury is commonly seen in athletes, they may complain of difficulty holding a tennis racket or throwing a baseball. Patients may also complain of instability or catching their thumb in pockets of their pants.


Tests used to confirm the diagnosis may include X-rays or MRIs. X-rays can be helpful as they allow your healthcare provider to stress the joint and see if the ligament is doing its job or if it damaged too much to stabilize the joint. In addition, sometimes X-rays show a small piece of bone pulled off the thumb metacarpal by the UCL ligament. This bone, called a Stener lesion, is a sign that surgery may be necessary as the bone can prevent the UCL from healing in its proper position without a surgical repair.


Treatment depends on several factors, including the extent of the injury, how long ago the injury occurred, the age of the patient, and the physical demands of the patient. If the tear is partial, and the thumb is not too loose, the patient is usually placed in a cast or a modified wrist splint (called a thumb spica) for 4 to 6 weeks. By immobilizing the damaged ligament, healing can take place while the thumb will be protected from further injury.

If the tear is complete or if the patient has significant instability due to the tear of the ulnar collateral ligament, then surgery may be considered. In acute cases, the surgeon may repair the torn ends of the ligament back together. If the ligament is torn from the bone, then the torn end will be sutured down to the bone itself.

If the injury to the ulnar collateral ligament is more chronic, then it is likely that a direct repair will not be possible. In this case, either another structure (graft) will be transferred to reconstruct the ulnar collateral ligament or one of the muscles at the base of the thumb can be advanced to compensate for the torn ligament.

Following surgery, patients will be placed in a cast for four to six weeks to protect the repaired ligament. At that point, gentle motion of the finger will begin. Most patients are able to play sports 3 to 4 months after surgery. Risks of surgery include infection, healing problems, and nerve injury. In addition, even with the surgical procedure, the damage to ligament will need time for healing.

Inadequate rehabilitation or insufficient protection following surgery can lead to stiffness and weakness of the thumb.

A Word From Verywell

Injury to the ulnar collateral ligament of the thumb can cause pain and instability. The instability of the thumb often makes activities such as gripping or pinching uncomfortable and difficult to perform. For these reasons, people with more significant injuries to the ulnar collateral ligament may choose to have a surgical procedure to repair or reconstruct the damage to ligaments. For minor injuries to the ligaments, often a course of immobilization with a splint or cast will allow the injury to heal.

2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Hung CY, Varacallo M, Chang KV. Gamekeepers Thumb (Skiers, Ulnar Collateral Ligament Tear). In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2019 Jan-.

  2. Tsiouri C, Hayton MJ, Baratz M. Injury to the ulnar collateral ligament of the thumb. Hand (N Y). 2009;4(1):12-8. doi:10.1007/s11552-008-9145-8

Additional Reading

By Jonathan Cluett, MD
Jonathan Cluett, MD, is board-certified in orthopedic surgery. He served as assistant team physician to Chivas USA (Major League Soccer) and the United States men's and women's national soccer teams.