Review Question - QID 211644

The patient has a left middle finger central slip injury (Zone III extensor tendon) as confirmed by a positive Elson's test. This can be managed with PIP extension splinting for 4-6 weeks while maintaining DIP motion.

Central slip (Zone III extensor tendon) injuries can occur after hyper-flexion injuries, direct blunt trauma or penetrating trauma to the digit. Diagnosis can be made by a thorough physical exam with a positive Elson's test. This is performed by placing the PIP joint over a table at 90 degrees and asking the patient to extend PIP against resistance. If the central slip is intact, the DIP joint will remain supple while if the central slip is disrupted, the DIP will be rigid. Management involves immobilization of the PIP joint while allowing for DIP motion to prevent stiffness and adhesions. If left untreated, these injuries can progress to a Boutonniere deformity.

Scott wrote an overview of the pathoanatomy and management of injuries to the flexion-extension system of the digits. He cites that any imbalance as a result of the injury will often lead to both visible and functional deformities. He stresses that while these deformities are initially supple they can become fixed and progress to IP joint osteoarthritis if not managed appropriately.

Posner and Green performed a review of various finger extensor tendon injuries. They emphasized that diagnosis is contingent on the understanding of the anatomy of the extensor apparatus as well as the ability to perform the appropriate physical exam. They note that the majority of acute injuries can be managed non-operative with immobilization alone whereas chronic conditions generally require surgical management.

Illustration A is a video demonstration of the Elson's test.


Incorrect Answers:
Answer 1: Full-time DIP splinting for 4-6 weeks is the preferred treatment for Zone 1 extensor tendon injuries (mallet finger).
Answer 3: MCP extension splinting is the management for Zone V extensor tendon injuries (sagittal band rupture).
Answer 4: Dorsal blocking splint of the PIP joint is indicated for unstable PIP joint dorsal dislocations.
Answer 5: While extension splinting of the PIP joint is the appropriate management of central slip injuries, the DIP should be allowed to have free ROM to prevent adhesions.