Your fingers are susceptible to injury because they are constantly exposed to potential dangers as you go through your day. "Jersey finger" is a common injury named after its usual mechanism of injury -- a player's finger gets caught in another's jersey, tearing the tendon that bends the tip of the finger. This injury requires surgical repair, followed by rehabilitation.
Finger flexion, or bending, is performed by two muscles: the flexor digitorum superficialis and the flexor digitorum profundus. The FDP tendon attaches to the front of the bone in the tip of the finger, allowing you to bend the tip of your finger. It is the FDP tendon that is damaged in a jersey finger injury.
You have FDP tendons in your index, middle, ring and small fingers. These tendons all connect to a common muscle in the forearm. According to a 2010 review published in the journal "Hand Surgery," 75 percent of jersey finger injuries happen to the ring finger. Upon initial evaluation, these injuries can be missed because the finger is so swollen. Delayed diagnosis can affect recovery because the torn tendon shortens and tightens, potentially limiting use of the finger.
Jersey finger injuries require surgery to repair the damaged FDP tendon. An incision is made along the front of the finger and the end of the tendon is found and pulled back up to the tip of the finger. Small holes are sometimes drilled in the bone and the tendon is sutured back in place.
A button -- much like a regular shirt button -- is sometimes placed over the fingernail, and the sutures are passed through the bone, fingernail and button to attach them more securely. The sutured tendon may also be affixed to the bone with metal anchors. These anchors remain in the finger permanently, while the button is removed 4 to 6 weeks after surgery.
The finger needs to be kept in the same position after jersey finger repair to allow scar tissue to develop and strengthen the repaired tendon. A custom low-temperature thermoplastic splint is made by a trained occupational or physical therapist. This splint is molded over the back of the forearm and hand, covering 1/2 the length of the forearm and ending past the tips of the fingers.
The splint is molded with the wrist bent forward to approximately 30 degrees, large knuckles bent to 30 degrees and fingers straight. This splint, called a dorsal blocking splint, is secured to the forearm and hand with fastening straps. The person is instructed to keep the splint on at all times immediately after surgery. A separate finger splint is sometimes made and applied to the back of the tip of the repaired finger to keep it bent.
Hand therapy is vital after jersey finger repair. Therapists perform wound care to the surgical incisions and move the fingers according to a specific protocol. The person is taught exercises to perform at home, initially removing the finger strap while leaving the splint on and bending the fingers using the opposite hand.
Three weeks after surgery, the splint is remolded with the wrist in a straight position. The person then begins place-and-hold exercises with the fingers pressed down into a fist using the opposite hand. In this position, the repaired tendons are gently tightened, holding the fingers in place for 3 seconds. Various protocols are used, and 10 repetitions of these exercises are commonly performed several times each day. The finger strap is worn between exercise sessions.
The splint comes off 5 to 6 weeks after surgery. The person can use his hand for simple, gentle daily activities, such as getting dressed and showering. Eight weeks after surgery, the person will start strengthening exercises which increase in difficulty over time. Normal use of the hand, including heavy lifting, is not typically allowed until 3 to 4 months after surgery.