Sprained Thumb

Causes of a sprained thumb 

A sprained thumb is typically caused by a sudden force or trauma, like falling on an outstretched hand, jamming your thumb or bending it too far backward or sideways. Sports injuries (especially in skiing, basketball and football) are common causes. 

Risk factors for a sprained thumb 

Participating in contact or high-impact sports 

Skiing (especially with a fall while holding a pole – this is even called “skier’s thumb”) 

Accidents or falls 

Previous thumb or hand injuries 

Symptoms of a sprained thumb 

Pain at the base of the thumb or in the joint 

Swelling and bruising 

Weakness or instability when gripping or pinching 

Limited range of motion 

A popping or tearing sensation at the time of injury 

Diagnosing a sprained thumb 

Diagnosis begins with a doctor doing a physical exam, checking for swelling, tenderness and joint stability. X-rays may be used to rule out fractures. In more severe cases, an MRI or ultrasound may be needed to evaluate ligament damage. 

Treatment of a sprained thumb 

Treatment depends on the severity of the sprain. Mild sprains may be treated with rest, ice, compression, elevation (also known as RICE) and a thumb splint. Moderate to severe sprains might require immobilization with a brace or even surgery if the ligament is torn. Physical therapy may be needed to restore strength and mobility.