Flexor Tendon Injury [Hand]
Overview
The flexor tendons are strong, smooth cords that connect the muscles of the forearm to the bones in the fingers and thumb. There are two tendons to each finger and one to the thumb. These tendons run inside tunnels at the wrist and in the fingers, helping bend the fingers in a way similar to a bicycle brake cable.
When a flexor tendon is injured, it can make it difficult or impossible to bend part of the finger or thumb. Because these tendons are close to the skin on the palm side of the hand and fingers, cuts and lacerations in this area can easily damage them.
Causes
The flexor tendons can be damaged by any cut across the palmar surface of the wrist or hand, especially at the finger creases where the tendons lie just beneath the skin. In some cases, the tendon may also be pulled away from the bone by a sudden, forceful pulling injury to the finger.
Symptoms
- A wound across the palm or fingers
- Inability to bend the finger either partly or completely
- A finger lying straighter than the adjacent fingers
- Pain when trying to bend the fingers
- Numbness in the finger if nearby nerves are also injured
Because the nerves run very close to the tendons, some injuries may involve both structures at the same time.
Diagnosis
X-rays may be taken if the injury was caused by glass or if there is concern for associated bone injury. Occasionally, ultrasound or MRI may be needed to provide more information about the tendon and help determine the extent of the damage.