A Boutonniere Deformity involves the tendons and ligaments of the fingers. The top of the finger has a complex arrangement of tissues of which the top sheet is called the central slip. The central slip helps straighten the PIP joint (middle knuckle) and bend the DIP joint (end knuckle).
A Boutonniere Deformity is often caused by a jamming or crush injury when the middle finger bone tears through the central slip leaving a hole the bone can extend through. The tendons and ligaments that normally straighten the PIP now bend the joint instead. These same tendons and ligaments that helped bend the DIP joint, now hyperextend the fingertip so that it bends backwards.
If left untreated, what seemed like "just a jammed finger", can end up becoming a long term deformity that is not easily corrected with therapy or even surgery. The best treatment for a Boutonniere Deformity is early treatment with appropriate splinting or casting.
The term Boutonnière (French for Buttonhole) Deformity refers to a finger where the middle joint (the PIP joint) is stuck in flexion (bent towards the palm) and the end joint (DIP joint) hyperextends (bends backwards). The middle finger joint may be enlarged due to a jamming injury and the finger may be painful to the touch for several weeks after an injury has occurred.
Oval-8 Finger Splints from 3-Point can be used on both the PIP joint and on the DIP joint to hold them in the proper position while the tissues heal. One or two splints can be used on each joint to hold them straight and may need to be worn for several weeks.
3pp Buddy Loops are recommended in milder cases of jammed or crushed fingers. 3pp Buddy Loops secure the injured finger to the adjacent finger(s) so the healthy finger can help the finger move without the need to use the muscles of the injured finger.
How to Treat a Boutonniere Deformity with an Oval-8 Finger Splint (video):