Boutonniere deformity
What is it:
Deformity of the finger characterised by hyperextension of the fingertip and flexion of the proximal interphalangeal joint.
Mechanism:
Can be caused by the extensor tendon of the finger being severed due to trauma or tearing/weaning of the extensor tendon due to an injury or condition e.g. rheumatoid arthritis.
Most often it is due to a forceful blow to the top side of a bent middle finger joint.
Clinical presentation:
- Loss of extension at the middle finger joint and hyperextension at the fingertip.
- A weak grip
- Inability to grasp and manipulate small objects with the top of the finger.
- Swelling and pain.
Management:
Non surgical:
- The creation of a custom thermoplastic splint that will hold middle finger joint into extension full time for around 6-8 weeks. When full extension of the joint can be maintained throughout the day progress to night splinting.
- Thermoplastic splinting of the fingertip into slight flexion may be indicated.
- Exercises can be gradually incorporated after splinting to improve range of motion and strength.
Surgical:
May be indicated when the deformity results from rheumatoid arthritis, the tendon is severed, a large bone fragment is displaced from its normal position or the condition does not improve with splinting.
