Medically reviewed by: Mark A. Yaffe(opens in a new tab), MD — Board-Certified Orthopedic Surgeon, Subspecialty Certified in Hand Surgery
Key Takeaways
- A broken thumb is a fracture of one of the thumb's three bones, from the tip bone to the metacarpal at its base, and breaks near the base joint are often the most serious.
- Pain, swelling, bruising, a crooked thumb, and a weak pinch are typical, but a bad sprain or ligament injury can look the same, so an X-ray is needed to confirm a break.
- Many thumb fractures heal with a splint or removable brace and hand therapy, while fractures that are displaced, unstable, or involve a joint may need pinning or screws.
- Bone healing often takes about four to six weeks, and grip and pinch strength can take two to three months or longer to fully return.
- Early evaluation helps the bone heal in the right position and lowers the risk of stiffness and later thumb arthritis.
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What Is a Broken Thumb?
A broken thumb is a fracture of one of the three bones that make up the thumb: the tip bone, the middle bone, or the long metacarpal bone that connects the thumb to the wrist. Fractures can be a simple crack or a complete break, and breaks that reach the joint at the base of the thumb are often more serious because that joint is so important for gripping and pinching.
Thumb breaks are among the most common hand fractures(opens in a new tab), and their care is part of broader hand and wrist(opens in a new tab) treatment. The thumb is responsible for a large share of hand function, so even a small break is worth treating properly.
What Causes a Broken Thumb?
Most broken thumbs come from a fall onto an outstretched hand, a direct blow, a crush injury such as a thumb caught in a car door, or a forceful bend backward during a collision or a catch. Contact sports, skiing, and ball sports are common causes, and so are workplace accidents and car accidents. If the injury happened while playing, read how sports injuries(opens in a new tab) are evaluated and treated.
Symptoms of a Broken Thumb
Symptoms usually appear right away and often include:
- Pain at the site of the injury that worsens when you move, grip, or pinch
- Swelling and bruising around the thumb or the base of the thumb
- A thumb that looks crooked, shortened, or out of position
- A weak or painful pinch, or trouble holding objects
- Tenderness when you press on the bone
- Numbness, tingling, or a pale or cold thumb, which need prompt care
You can sometimes still move a broken thumb, so being able to bend it doesn't rule out a fracture. A bad sprain or a torn ligament can cause the same pain and swelling, and the two can't be told apart without an exam and X-rays. For a closer look at how to sort out a possible break in the hand, see these broken finger signs(opens in a new tab).
How Is a Broken Thumb Diagnosed?
A hand surgeon starts with how the injury happened and a hands-on exam that checks for tenderness, alignment, motion, and stability of the thumb joints. X-rays from several angles confirm whether the bone is broken, where, and whether the pieces have moved out of position. A CT scan is sometimes used when a fracture involves a joint and more detail is needed. The same exam checks the ligaments, since a ligament injury at the base of the thumb, often called skier's thumb, can happen with or without a small fracture.
Pain on the thumb side of the wrist can also come from other problems, including a distal radius fracture(opens in a new tab), a scaphoid fracture(opens in a new tab), or, with long-standing pain and no injury, thumb CMC arthritis(opens in a new tab).
Non-Surgical Treatment for a Broken Thumb
Many thumb fractures heal without surgery, particularly when the bone is still in good alignment. Treatment typically includes:
- Immobilization: A splint or removable brace holds the thumb still while the bone heals. Dr. Yaffe uses splints instead of casts whenever possible, including custom splints made by Certified Hand Therapists, and a removable fracture brace can be an option for some fractures.
- Ice and elevation: Keeping the hand raised above the heart and applying ice in the first few days can reduce swelling and pain.
- Pain relief: Over-the-counter medication can help control pain and swelling.
- Follow-up X-rays: Repeat images in the first weeks confirm that the bone is staying in position.
- Hand therapy: Once the bone is stable, guided exercises restore motion, grip, and pinch strength.
For fractures of the fingers, which are treated in a similar way, this guide to broken finger treatment(opens in a new tab) explains what to expect.
Surgery for a Broken Thumb
Surgery is considered when a fracture is displaced, unstable, or rotated, when it involves the joint surface, or when it doesn't heal properly with conservative care. A well-known example is a break at the base of the thumb metacarpal that enters the joint, such as a Bennett fracture, which tends to slip out of position without fixation.
For these fractures, Dr. Yaffe uses minimally invasive surgery(opens in a new tab) techniques such as temporary pinning and micro screw fixation, which hold the bone in position while it heals and avoid the need for large incisions. When surgery is needed, he provides expeditious surgical care in-office. Because the thumb is so important for hand function, getting the alignment right early also helps protect the joint over the long term. A fracture that involves the joint can increase the risk of arthritis later, which is one reason a thumb that stays painful after healing is worth re-checking.
How Long Does a Broken Thumb Take to Heal?
Most thumb fractures need about four to six weeks for the bone to heal, though the timeline depends on which bone is broken, how severe the break is, and whether surgery was needed. Light daily activities are often possible earlier, but pinching, gripping, and sports usually have to wait until the bone is solid, and strength often takes two to three months or longer to return. Stiffness and swelling can linger, which is why hand therapy matters. For a broader overview, see this fracture healing timeline(opens in a new tab).
When to See a Hand Surgeon
See a hand surgeon as soon as you can after a thumb injury, since early evaluation helps the bone heal in the right position and helps avoid stiffness. Seek care right away for an open wound, numbness, a thumb that looks pale, cold, or clearly deformed, or pain that is severe or not improving after a day or two. If you aren't sure what to do first, this guide on what to do when you think you broke a bone(opens in a new tab) walks through the first steps, and this overview of care after ER(opens in a new tab) explains what comes after an urgent care or emergency room visit. If your pain is mostly at the wrist, you may also want to read about broken wrist(opens in a new tab) treatment.
Dr. Yaffe can see you quickly, and even emergently when needed, at Schaumburg(opens in a new tab), Elk Grove Village(opens in a new tab), and Buffalo Grove(opens in a new tab). To get started, schedule an appointment(opens in a new tab) online, and it helps to note how and when you were injured.
Frequently Asked Questions
How do you know if your thumb is broken?
A broken thumb usually causes pain and swelling right away, often with bruising, tenderness over the bone, a crooked appearance, or a weak pinch. Because a sprain can look the same, an X-ray is the only reliable way to know. See a doctor the same day or the next day if you suspect a break.
What does a broken thumb look like?
A broken thumb is often swollen and bruised, and it may look bent, shortened, or out of line with the rest of the hand. Some fractures cause very little visible change, so a thumb that looks normal can still be broken.
How long does a broken thumb take to heal?
Most thumb fractures heal in about four to six weeks. Pinch and grip strength can take two to three months or longer to fully return, and fractures that need surgery or involve a joint may take longer.
What should you do for a broken thumb?
Keep the thumb still with a splint or by taping it gently to the hand, remove rings, apply ice wrapped in a cloth, and keep the hand raised above the heart. Take over-the-counter pain medication if needed, and get an X-ray and an evaluation by a hand specialist as soon as possible.
Can you still move a broken thumb?
Sometimes. Many people can still bend a broken thumb, so being able to move it doesn't mean it isn't broken. Pain, swelling, and tenderness over the bone are better clues, and an X-ray confirms the diagnosis.
