What is a central slip injury?
The central slip is part of the extensor tendon that straightens the proximal interphalangeal joint (PIP joint). It is often injured from joint dislocation or forced flexion of the PIP joint. The tendon can tear away from the bone or pull a small fracture fragment with it.
What is a Boutonnière Deformity?A Boutonnière deformity is the result of an injury to the central slip, which is the tendon that straightens the middle joint of your finger. The result is that the middle joint of the injured finger cannot straighten, while the end joint bends back into hyperextension because of the force placed on the tendon creating the deformity. Unless this injury is treated promptly, the deformity may progress, resulting in permanent deformity and impaired function.