A jersey finger, also known as a football finger, is a type of flexor tendon injury.(1) The flexor tendons of the hand play a very important role in functioning of the hand. The flexor tendons get associated with each other while performing movements of the fingers like flexing and bending the fingers, which also help the hand while performing infinite tasks. Every finger particularly consists of two long flexor tendons called as the FDS i.e. flexor digitorum superficialis and FDP i.e. the flexor digitorum profundus. The flexor digitorum superficialis and the flexor digitorum profundus begin from the forearm and pass through the carpal tunnel of the wrist and insert on the phalanges i.e. the finger bones.
A jersey finger is caused due to the tearing of the flexor digitorum profundus tendon from its attachment at the distal phalanx i.e. the bone located at the ending point of the finger. This generally occurs if a sudden force is exerted on the fingertip. This type of injury most commonly occurs when a football player tries to grab the jersey of a moving opponent and hence the name jersey finger. The flexor digitorum superficialis remains intact and is not affected in this type of injury.
The structure and function of the hand are very closely related to one another. The bones and the soft tissue structures of the hand stand on a very delicate balance. The functioning of the entire hand gets affected when there is a small disruption of the structural balance between the soft tissues and the bones.
Types of Jersey Finger or Football Finger
Leddy and Packer classification method is used to categorize jersey finger based on the presence of fracture and the level of tendon retraction.
- Type I: FDP tendon retraction to the palm. This leads to compromised vascular supply and usually requires surgery ASAP.
- Type II: Retraction of FDP to the level of the PIP joint.
- Type III: Avulsion fracture(2) with retraction of the FDP to the level of the DIP joint.
- Type IV: Fractured osseous fragment with simultaneous avulsion of the tendon from fracture fragment usually into the palm.
Causes of Jersey Finger or Football Finger
- Jersey finger very frequently occurs in contact sports like football and rugby.
- Catching of finger in a jersey and tearing a tendon while tackling opponents in contact sports is the common cause of jersey finger.
- A jersey finger injury most frequently affects the ring finger of hand.
Signs and Symptoms of Jersey Finger or Football Finger
- A jersey finger leads to tearing away of the flexor tendon creating discomfort in bending and flexing the finger.
- Pain is felt in the tip of finger.
- Inability to bend the finger. Jersey finger injury forces the distal interphalangeal joint(3) to straighten out even if it is bent forcibly.
- Swelling at the tip of the finger.
- Bruising at the tip of the finger.
- Tendon may possibly be felt as a bunch of soft mass on the palmar side of hand.
Treatment for Jersey Finger or Football Finger
- Resting the finger.
- Application of ice to the finger.
- Seek immediate medical attention if the finger is stuck in an extended position and cannot be moved.
- Conservative Therapy is not helpful in treating jersey finger and almost always surgery is required.
- Surgery is usually performed as an outpatient under regional anesthesia or general anesthesia. Surgery involves identifying the flexor digitorum profundus tendon and reattaching it back to the distal phalanx. Incision is made on the palmar side of the affected finger which may be extended into the palm to identify and repair the retracted tendon. Sutures and anchors are required to hold the tendon down to the bone. In case of fracture at the tendon attachment, it needs to be fixed during the same surgery. Pins or screws may be required to fix the fracture.
- If the retracted tendon is left untreated for a few weeks then it may not be possible to get the retracted tendon back to the bone. Flexor tendon reconstruction needs to be performed in such cases. Flexor tendon reconstruction involves taking a tendon graft and using it as a substitute. Tendon graft is usually taken from the palmaris longus tendon from the forearm as removal of this tendon does not lead to any significant loss of function. However, there is a high risk of stiffness, scaring and decreased range of motion with this procedure, hence it is generally avoided.
- Rehabilitation is very important as the tendons become very stiff. Early movement after surgery is important to avoid stiffness.
- The most skilled and efficient orthopedists and hand surgeons have been challenged by the flexor tendon injuries for decades now. Improvised treatment and repair techniques have developed over years of research and experience and the results have improved to a large extent, however, the patients are often left with problems like scar tissue formation, stiffness, and decreased function of the hand.
Exercises for Jersey Finger or Football Finger
Stretching and strengthening exercises may need to be performed during the recovery phase to gain complete motion of the jersey finger.
Stretching Exercises for Jersey Finger or Football Finger
- DIP Flexion: This exercise is performed by grasping the injured finger with healthy hand placing the thumb on the top of the finger beneath the adjoining joint of the fingernail. Bend the injured finger gradually towards the adjoining joint of the fingernail. Hold this position for about 6 seconds and release. Perform this exercise for about 8 to 12 times.
- PIP Extension: This exercise is performed by placing the healthy hand on the table with the palm facing the upward direction. Keep the hand with injured finger on the healthy hand. Grasp the below area of the middle joint of the injured finger by using the fingers and thumb of the healthy hand. Bend and straighten the ending two joints of the injured finger. Perform this exercise for about 8 to 12 times.
- Finger Extension: This exercise is performed by placing the hand on a table with palm facing downwards. Raise and drop the injured finger from the table. Perform this exercise about 8 to 12 times.
- Isolated PIP flexion: This exercise is performed by placing the injured hand on the table and pressing down the unaffected fingers with the help of the healthy hand. This will assist the affected finger to move freely. Gradually bend the injured finger. Hold this position for about 6 seconds and then straighten it. Perform this exercise about 8 to 10 times.
Strengthening Exercises for Jersey Finger or Football Finger
- Tennis Ball Squeeze: This exercise involves holding a tennis ball in the hand and squeezing it as hard as possible ensuring comfort without pain. Hold for 5 seconds and release. Repeat 5 to 10 times ensuring there is no exacerbation of symptoms.
- Towel Grab: This exercise is performed by folding the towel in half and putting it flat on a table. Place the injured hand on the towel with palm facing downwards. By grabbing the towel scrunch it as far as possible applying pressure towards the fist until a mild to moderate pain free stretch is felt. Gradually straighten the fingers releasing the towel back on the table. Perform this exercise for about 8 to 12 times.
- Finger Spring: This exercise is performed by wearing a rubber band around the outer surface of fingers including thumb. Stretch the rubber band by stretching the fingers. Perform 2 sets of 15.
Apart from this there are also some tendon glide exercises that can be performed to improve range of motion of the affected finger.
Investigations for Jersey Finger or Football Finger
A complete subjective and physical examination is necessary to diagnose a jersey finger. A thorough neurovascular examination(4) of the hand and the digits is performed to assess for injuries to the nerves and vessels. Typically, an ultrasound and an x-ray are required for confirming the severity.