EPL tendon Rupture in Colles Fractures
What is the EPL tendon?
- The EPL = Extensor Pollicus Longus tendon runs along the back of the wrist to the thumb and wraps around Lister’s tubercle, using it as a pulley.
- It allows you extend your thumb and lift it up when your hand is palm downward.
- The muscles are in the forearm. Tendons are like rope joining the muscles to the fingers and thumb. There is a strap of tissue ( extensor retinaculum) on the back of the wrist that holds the tendons down. There are 6 tunnels on the back of the wrist containing the Extensor tendons to the thumb, fingers & wrist.
- It runs along the back of your wrist
- The Tunnels are lubricated by the fluid produced by a thin layer of tissue called synovium.
- Synovium around a tendon is called Tenosynovium
- Inflammed synovitis is called Synovitis
- Hence "teno-synov-itis”.
- If the EPL ruptures the thumb droops down.
How is it related to a Colles fracture?
- A Colles fracture is a break in the distal radius (the main forearm bone near the wrist).
- This is the commonest fracture, often from a fall onto an outstretched hand.
- In some patients, the fracture edges can be rough and they “saw” their way through the EPL tendon.
- This applies particularly when the fracture involves Lister’s tubercle – a prominence on the back of the radius around which the EPL changes direction
- The tendon may wear down and rupture, usually weeks – years after the fracture.
- Paradoxically, rupture is more frequent after nondisplaced (less severe) fractures.
Symptoms
- Pain & swelling on back of the wrist with thumb extension
- Sudden Inability to lift the thumb up (extend the thumb) without warning.
- Pain settles after the rupture
Treatment
- Prevention is better than treating a ruptured tendon.
- EPL Decompression - Removing the EPL from the groove adjacent to Lister’s tubercle & placing it superficial to the retinaculum
- Once ruptured, the EPL tendon cannot heal by itself.
1. Repair of the tendon is not possible – The tendon is often frayed over a considerable distance before it eventually ruptures
2. EI to EPL tendon transfer.
- There are 2 tendons that extend the Index finger ( EI & EDC tendons)
- The EI tendon is available for transfer because the EDC tendon to the index finger can still provide normal index finger extension on its own
- The Extensor Indicis (EI) tendon (used to extend the index finger) is redirected to take over the function of the EPL.
- Surgery is usually performed as a day procedure.
- The thumb and wrist are protected in a cast for 6 weeks.
- The transfer is intentionally made “tight” because it tends to stretch over a period of weeks. When you first come out of the cast you will be convinced that the thumb will “never move again”. It will. By 10 - 12 weeks most patients have full motion.
- Hand therapy helps restore movement and strength.
- Gradual introduction of motion and limited lifting—no pinching or gripping initially.
- Strengthening exercises begin around 8 weeks, with lifting restrictions gradually easing.
- Most patients achieve functional recovery by 10–12 weeks, with ongoing therapy as needed.