For a Mallet finger injury, how should the DIP be immobilized?

• A. Immobilize in full extension for 6-8 weeks WITHOUT FLEXING
• B. Immobilize with the DIP in flexion
• C. Immobilize the DIP with the PIP flexed
• D. Remove splint after 2 weeks

Answer: (A)

Immobilizing the DIP in full extension lets the terminal extensor tendon heal in the length it’s meant to be, preventing a persistent flexed posture and extension lag. In a mallet finger, the injury disrupts the extensor mechanism at the distal phalanx, often with a small bony avulsion. Keeping the DIP extended maintains tension on the repaired or reattaching tendon, promoting proper healing. Extending the DIP for about 6–8 weeks with a splint provides time for the tendon or bone fragment to secure, and removing the splint after only 2 weeks would be premature and increase the risk of a deformity. Immobilizing in flexion, or with the PIP flexed, fails to restore the extensor mechanism and would not correct the deformity.