A jersey finger is an injury causing rupture of the Flexor Digitorum Profundus (FDP) tendon – the tendon responsible for bending the fingertip.
Tendons connect muscles of the forearm to bone. The FDP tendon is located on the palm side of the finger and attach to the small bone at the fingertip (distal phalanx). The pull of this tendon bends the fingertip.
Jersey finger can occur if the tendon comes off the bone or if it pulls a fragment of bone with it causing a fracture.
This injury commonly happens in tackle sports and the ring finger is most commonly involved.
Sporting injuries are the most common causes.
These injuries commonly occur in sports such as rugby when attempting to grab an opponent’s shirt / jersey. The fingertip is forcibly straightened and the tendon is pulled off.
Signs and symptoms
Diagnosis is based on examination of the finger and scans.
The fingertip will be straight, and tip cannot straighten on its own. There will be bruising, swelling, pain and tenderness.
This is used to determine if there is an associated fracture and if the finger joint is in normal alignment.
This is usually not necessary but can be used to show detachment of the tendon if the diagnosis is uncertain. This will also show how far a ruptured tendon has retracted.
If left alone, the fingertip will not bed and hence cause problems with function causing loss of grip and weakness.