FDP TENDON AVULSION - JERSEY FINGER

FLEXOR TENDONS - GENERAL

   



There are 2 tendons acting on each finger to bend or flex the finger. The tendons run up the front of the finger in a tunnel (flexor sheath) which is lined by synovium , a lubricating tissue which allows the tendon to glide without resistance. Thickenings of the flexor sheath are called pulleys and they hold the tendon down against the bone and prevent bowstringing.

When a tendon is cut or pulls off the bone it results in bleeding up and down the sheath. The blood turns to scar tissue and hinders gliding of the tendons. Direct repair of a tendon is therefore only possible for 2–3 weeks after an injury. After this time the scaring becomes too dense and the tunnel becomes narrowed and rough thus preventing smooth gliding of the tendon.

The muscle continues to act on the proximal end of the tendon. This muscle effect results in the tendon retracting so that over a period of time the gap between the divided tendon ends becomes great.

POSSIBLE CAUSES

• Tendon lacerations.
• Football tackles.

TREATMENT

Direct Repair

• Smaller cut extending proximally from finger tip until tendon is retrieved.
• Tendon reattached using button on back of finger or bone anchor.
• Stay overnight in hospital.
• Plastic splint 6 weeks.
• Significant activity restriction for 3-4 months.
• Hand therapy.

Late Repair

1. Do Nothing

• Finger tip unable to bend.
• Pain in finger or palm may never completely settle.
• May develop carpal tunnel syndrome due to swelling in the palm.

2. Resect the retracted tendon if pain persists in the palm.

3. Fuse the end joint (D.I.P.) of the finger

• Small cut on back of finger.
• 6 weeks in a splint.
• No significant need for physiotherapy.
• Pain in finger or palm may never completely settle.
• May develop carpal tunnel syndrome due to swelling in the palm.

4. Two-Stage Flexor Tendon Graft

1st Stage

• Large cut.
• Overnight stay in hospital.
• Plastic rod inserted in finger.
• Wound heals after 2 weeks.
• No splintage.

2nd Stage

• Smaller cut.
• Removal of plastic rod and replacement with tendon graft usually harvested from forearm.
• Plastic splint 6 weeks.
• Significant activity restriction for 4 months.
• Hand therapy.