A Boutonniere deformity is caused by a change in the balance of muscles/tendons in the finger, often from an original trauma that has not been appropriately managed or treated in the past. If there is damage to the tendon along the back of the hand that is left untreated, the tear can prevent the middle joint from straightening. Without treatment, this stretching over the middle joint can cause the tendons at the end joint to over-work, causing the tip of the finger to hyperextend. Depending on the original injury and time since injury, treatment can differ.
Definition
Boutonniere deformity is the term used to describe the finger when it is flexed at the proximal interphalangeal joint (middle joint) and hyperextended at the distal interphalangeal joint (end joint or fingertip). It is usually a result of trauma and is caused by a rupture or tear to the central slip. A boutonniere deformity can also be the result of a laceration injury to the central slip and dorsal capsule or can be secondary to a burn injury and rheumatoid arthritis.
Causes
A boutonniere deformity results when the triangular ligament and the central slip of the extensor tendon are disrupted. This disruption of the ligament and tendon causes the lateral bands to displace volarly. This results in forced flexion of the finger, and subsequent limitation of the DIP joint to extend. Over time, the oblique retinacular ligament gradually contracts or tightens.
When the tendon and the skin are cut, this is referred to as an open injury. This often occurs from a laceration injury. When the tendon rupture does not harm the skin, it is referred to as a closed injury. This often occurs when the back of the finger is impacted while in a bent position, such as a ball injury.
Signs & Symptoms
Commonly seen with:
- Central slip injuries – open and closed injuries.
- Ball vs finger and sports-related injuries
- Direct trauma or forceful blow to the back of hand/finger
- Can be caused by OA & RA
- Jammed finger/traumatic avulsion fracture
Symptoms/presentation:
- The finger at the PIP joint (middle joint) cannot straighten and the DIP (fingertip) cannot be bent.
- Swelling and pain may occur and continue along the top of the PIP joint.
How Can I Prevent Boutonnière Deformity?
- Get appropriate treatment for central slip and laceration injuries
- Compliance with splinting
- Getting immediate treatment for injuries to the back of the hand to avoid complications such as Boutonniere deformities.
- Appropriate rest for injured structures
- Protection when returning to sport or high-risk activities, such as taping.
Treatment
Treatment of Boutonniere deformities can be both surgical and non-surgical depending on severity, structures involved, trauma and time since injury. Non-surgical treatment involves splinting and immobilisation of the affected joint. Splints are usually maintained for 3-6 weeks depending on severity, age of the person, and time since injury. This will allow the tendon to heal and allow for the PIP joint to straighten. Patients may then be instructed to wear the splint at night or during activities for several more weeks.
Management of these injuries may also require stretching and strengthening of the affected structures, scar management, and taping for sports for 3 to 4 weeks following full time splinting. Surgical treatment is often used if the tendon is severed or if there is a significant displacement of bone as a result of a fracture. The deformity can become more difficult to correct if it is left untreated for longer than 3 weeks and may require longer healing times and splinting.
Melbourne Hand Therapy Can Help You
At Melbourne Hand Therapy we treat Boutonniere deformities with the use of stretching, splinting, strengthening and scar management. We treat patients postoperatively and those who require non-surgical management. Our treatment is tailored to your individual needs and is dependent on the type of injury, age of injury, presentation and severity. Book in today to see one of our highly skilled therapists if you are experiencing any of the symptoms above.
