Q: I just got this very cool metal ring for a finger injury and I'm wondering if you've ever heard of it? It's called a pulley splint. Looks like jewelry. What does it really do?

A: It sounds like you are benefitting from a newer feature in treatment related to flexor pulley injuries: a pulley splint. This type of metal ring fits over the injured pulley and provides support during the rest period needed for healing. Rock climbers and fastball pitchers experience this type of injury most often and can benefit from these new pulley splints.

To help you understand the splint's intended purpose, a brief anatomy lesson may help. The tendons that move the fingers are held in place on the bones by a series of ligaments called pulleys.

These ligaments form an arch on the surface of the bone that creates a sort of tunnel for the tendon to run in along the bone. To keep the tendons moving smoothly under the ligaments, the tendons are wrapped in a slippery coating called tenosynovium. The tenosynovium reduces the friction and allows the flexor tendons to glide through the tunnel formed by the pulleys as the hand is used to grasp objects.

Nonoperative care for these ligamentous injuries is usually under the supervision of a hand therapist (occupational or physiotherapist). Treatment is designed to reduce pain, restore motion, and improve function. The therapist may provide a custom-made (designed for each individual patient) splint when needed. Splinting has been shown to allow early active motion that protects the healing ligament while encouraging healing. That's what this pulley splint does, too.

Surgery to repair or reconstruct the damaged soft tissues is advised when there is a partial or complete (avulsion) tear of the ligament away from the bone. Operative care is also required when the patient does not respond to conservative care (such as the splinting you are using) and/or when joint instability persists.

Reference: Zahab S. Ahsan, and Jeffrey Yao, MD. Ligamentous Injuries of the Hand. In Current Orthopaedic Practice. July/August 2012. Vol. 23. No. 4. Pp. 313-317.