What is Boutinneire Deformity?
Boutonniere is a French word meaning buttonhole. When the middle joint of your finger is bent while the distal joint is pointed upward, this is called a boutonniere deformity. It gets its name when the tendon on the top of the finger that extends from the furthest joint to the middle joint tears, it looks like a buttonhole.
To make sense of this, it helps to have a little background on the anatomy of the hand. The hand has over 29 bones, 29 joints, and 23 ligaments. There are eight carpi (wrist) bones and four metacarpal bones within your palm area. The metacarpal bones start at the wrist and extend up to the knuckles and thumb.
The knuckle is where the metacarpal bone connects with the phalanges or fingers. The medical term for your knuckle is called metacarpophalangeal joint (MCP). The thumb knuckle is called carpometacarpal joint (CMC).
The middle joint of the phalanx (finger) is called proximal interphalangeal joint (PIP). For the thumb, the middle joint is called metacarpophalangeal joint (MP). The tip of the finger joint is called distal interphalangeal joint (DIP). The thumb’s distal joint is called interphalangeal joint (IP).
Ligaments are tough fibrous tissue which helps bone connect to bone. Ligaments are important because they not only allow for joint movement, but they also stabilize a joint which means they prevent unwanted movements too. For example, we have ligaments on either side of our PIP joints; they are called collateral ligaments. They allow the finger to flex (bend) and extend (straighten), but they don’t allow the finger to move side to side.
Tendons connect muscle to bones. Every movement we make requires bones, tendons, and ligaments. When one of these structures is injured, it can cause deformity and immobility which is the case with the boutonniere deformity.
The tendon on the top (dorsal) side of the DIP (tip of a finger joint) extends down to the PIP (middle of a finger joint). When this tendon is injured at the PIP, it no longer allows for that joint to straighten and it causes the DIP to extend (bend upwards).
What causes boutonniere deformity?
The three most common causes of boutonniere’s deformity are trauma, arthritis, or burns. Some people are born with a mild case of (congenital) boutonniere deformity, but this is rare.
When trauma occurs on the top side of the PIP (middle) joint, it can cause a tear of the tendon. Trauma may include anything from a laceration (cut) to dislocation (jammed finger) of the joint. Rheumatoid arthritis can be painful and debilitating. In severe cases, joints within the hand become deformed. This deformity, if at the PIP joint, can cause a boutonniere deformity.
With a full-thickness (3rd degree) burn over the PIP joint, the damage to the tissue is significant enough where the tendon is no longer healthy and is unable to attach to the bone.
Symptoms of Boutinneire Deformity
In the case of a traumatic incident, the injury occurs instantaneously and causes an immediate deformity. Pain and swelling are likely to settle into the joint.
In cases where there is a slow progression of deformity, as with rheumatoid arthritis, over time the joint becomes stiffer, and the flexion (bending) of the PIP joint worsens over time.
How is boutonniere’s deformity diagnosed?
If a traumatic incident occurred, the physician would determine if further diagnostics are necessary beyond a physical exam. The cause of the injury will help the doctor understand what may be going on and if any further examination beyond the physical exam is needed.
For example, if you “jammed” your finger, the physical exam would include you showing the doctor if you can straighten your PIP joint. With a boutonniere’s deformity, you would be unable to extend the PIP or flex the DIP joint. An X-Ray may be ordered, even though the doctor knows it is a boutonniere’s deformity because he or she may want to ensure there are no broken bones.
In the case of a slow onset, your doctor would monitor your hand and finger deformities over time. The goal would be to prevent a boutonniere’s deformity through splinting; however, it is not always avoidable. Regardless if it was a traumatic injury or slow onset, the clinical presentation is the same.
Treatment of Boutinneire Deformity
Unfortunately, there is no self-treatment for a boutonniere’s deformity. Timing is everything with, in most cases if not properly treated with 3-weeks, it is much more challenging to treat. Medical treatment is required.
With trauma not caused by lacerations, or slow onset, your physical or occupational therapist (PT or OT) will customize a finger splint allowing the PIP joint to extend and the DIP joint to bend. The goal of the splint is to position both joints back into a resting, or neutral, position to allow the tendon to heal. The healing process takes approximately six weeks; for some, even after six weeks, they may need to wear the splint at night.
Your PT or OT will carefully select graded exercises for your finger and hand during the healing process. If you have rheumatoid arthritis, your PT or OT may also provide hand splints for you to prevent further deformity of all the joints within your hand.
When conservative treatments do not work, surgery may be indicated. Even with surgery, the deformity will never fully go away. Surgical cases are usually only for the most severe cases of deformity and for those fingers that are “limber.” If the PIP and DIP deformity occurred some time ago and now has a contracture (stuck), surgery is most likely not the appropriate intervention. It is best to visit with your hand surgeon to determine the right treatment.
In the case of a laceration that caused the deformity, it is recommended a hand surgeon be advised. A hand surgeon will need to fully access the risk of infection as well as if there is any other damage to the tendons, ligaments, nerves or joints.
Early treatment is the key to managing the boutonniere’s deformity successfully. It cannot be treated, or heal, on its own. The sooner you get medical care; the more likely conservative care will work for you.
As a consumer of health care, you have a choice in finding the right provider for you. Do your homework and search for a health care provider, like a physical therapist, with excellent outcomes, great customer reviews, and can provide you the care you need for a reasonable cost.
In most states, you can be seen by a PT first, without a physician’s order. To determine if your state has direct access, please visit the American Physical Therapy Association’s website Physical Therapy Direct Access By State.
To get started with conservative care today, you can find a highly qualified PT or OT in your area. There are many qualified PTs and OTs, so to find one near you, please click on Find A Clinic. This link will help you find a PT or OT that has top national rankings for treating the hand.