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 to each finger and one for the thumb. The tendons run inside tunnels at the wrist and in the fingers, and they bend your fingers in the manner of a bicycle brake cable.
The 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 under the skin. Occasionally, the tendon is detached from the bone by a violent pulling injury to the finger.
- A wound across the palm or fingers
- Inability to bend the finger either partly or totally
- Finger lying out straighter than the adjacent digits.
- Pain when trying to bend the fingers
There may also be numbness of the finger due to injury to the nerves, which lie close to the tendons.
X-rays may be taken if the injury was caused by glass. Occasionally, ultrasound or MR scans are needed to give more information about the tendon.