The clearest symptom of boutonnière deformity is a bend in your finger that you can’t straighten out. This symptom can start as soon as you are injured, or it might take a few weeks to appear. Other symptoms can be related to the injury that causes the deformity and might include:
- Swelling and pain on the middle joint of your finger.
- A cut in the top of your finger.
If you have a boutonnière deformity, you should see a healthcare provider as soon as possible. If it’s not treated, the bend in your finger can get worse over time, and you might even have permanent problems using your fingers and hands. Since the boutonnière deformity is caused by damage to the hand, you might also have other symptoms or injuries that also need a healthcare provider’s care.
The most common causes of this deformity are injuries and rheumatoid arthritis.
- Injury. The deformity can be caused by injuries to your hand. For example, instance, your finger could get hit while your finger joint is bent, or you could have a cut in the top of your finger joint that goes through the tendon. Sports injuries can also cause this problem.
- Rheumatoid arthritis. Rheumatoid arthritis, or RA, is an autoimmune disease that causes damage to your joints and connective tissues in your body. RA can cause inflammation that can hurt the tendon and middle joints of your finger, causing the deformity.
If your healthcare provider thinks you have boutonnière deformity, they will ask you some questions and do a physical exam of your finger and hands. Questions your healthcare provider might ask include:
- When did your symptoms start?
- Were you injured?
- Can you bend your finger back to being straight?
Your healthcare provider might also order imaging tests, like x-rays, to take pictures of your finger and look for any other problems like broken bones or slipped tendons. These tests will help your symptoms are caused by boutonniere deformity or a similar injury.
If your healthcare provider diagnoses you with boutonnière deformity, they might suggest a few different treatment options:
- Splint. The most common treatment for boutonnière deformity is a finger splint. This is a stiff sleeve that goes over the finger and is secured with tape or Velcro. The splint helps keeps your finger straight for up to 6 weeks, giving the tendon a chance to heal. You may also need to wear a protective splint while playing sports for several weeks more.
- Surgery. Surgery is more serious, but might be needed if the splint doesn’t help, if your deformity is caused by RA, or if the tendon in your finger is cut all the way through. In these cases, your healthcare provider might recommend surgery, like joint replacement or tendon repair, to help you get some of the function of your joints back.
Sometimes, this deformity is caused by conditions that you can’t prevent, like rheumatoid arthritis. However, injury is also a common cause of this condition. Taking some commonsense safety steps can help reduce the chance that your finger will be hurt. These include:
- Drive safely. Automobile accidents are one of the leading causes of injuries in America.
- Be careful when playing sports. Sports and exercise can cause injuries to many parts of your body, including your hands. Using the proper equipment, stretching, and playing sports safely can lower your chance of injury.
- Be aware of your surroundings. You should look for things that might cause you to trip and fall like ice or extension cords. Be safe when moving furniture or lifting anything heavy to avoid getting your fingers and hands caught under these objects.
A boutonnière [BOOT-tuhn-yehr] deformity is a condition that causes the middle joint of your finger to stay bent while the tip of your finger bends back. If you have this condition, you might not be able to straighten out your finger, even if you try. This condition can happen because of rheumatoid [ROO-muh-toyd] arthritis (RA) or osteoarthritis [ah-STEE-oh-AR-thry-TIS]. It can also happen if the tendons in your finger are hit or cut (for instance, if your hand gets stepped on or crushed in a door). When this happens, the boutonniere deformity can be called a “jammed finger”.
Mallet finger is a similar finger deformity that can be caused when a ball or other object hits that tip of your finger or thumb. Sometimes, this blow can be strong enough to tear the tendon that straightens the finger, which can make it bend without you being able to straighten it.