Scenario: Katherine was walking her dog with the lead wrapped around her hand. Her dog suddenly pulled and the lead caught and yanked her finger. The middle joint is now swollen and she cannot straighten her finger.
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.
If left untreated a boutonniere deformity can occur, where the PIP joint rests in a flexed position and the distal interphalangeal joint (DIP joint) sits in hyperextension. Without the central slip to straighten the PIP joint, other parts of the extensor mechanism collapse creating a deforming force on the finger joints.
Treating a Central Slip Injury?
Treatment includes holding the PIP joint in an extended position for 6-8 weeks using a cylinder thermoplastic splint or a dynamic PIP extension splint. Care is taken to keep the PIP extended at all times.
Your hand therapist can show you how to safely don and doff the splint for hygiene whilst maintaining the integrity of the healing central slip tendon. DIP joint flexion exercises are important to maintain the natural balance of the mechanism and prevent a boutonniere deformity.
Your hand therapist can also help to reduce oedema with compression garments.
If you have any questions about a central slip injury, or about another injury to the fingers, hands, wrist, and arms and would like to book an appointment, get in touch today.