Most athletes have had the experience. You are reaching to catch a ball and somehow you mistime it just a little bit. Instead of the ball nestling nicely into your palm, it strikes the tip of your finger. The pain is instantaneous. You reach down, cradle your finger and go back to playing. After the game is over you notice your finger is swollen and painful but you can bend it and think to yourself “it will get better,” but after a few weeks the pain persists, the swelling doesn’t go away and you wonder if you should go to the doctor for something that seems so trivial.
The truth is that so-called “jam” injuries of the finger present with a wide variety of problems that can be effectively treated without surgery and treatment usually results in excellent function of the injured finger. However, without proper assessment and treatment many people will develop significant stiffness and deformity. The three most common finger injuries requiring intervention are: The Boutonniere, Volar Plate and Mallet finger injury.
Boutonniere deformities are injuries to the middle joint of your finger. This injury causes a tear in the extensor tendon over the middle joint called the “central slip” and secondary injury of the ligament that supports a structure called “the lateral bands.” The injury is actually a twofold problem. The central slip tear prevents the athlete from fully straightening the middle joint of the finger. The loss of support causes the lateral bands to slip, and the patient develops the characteristic deformity seen in Figure 1. Treatment in the early phase is actually relatively simple and quite effective. If the joints of the finger remain supple and easily positioned, the finger is splinted with the middle joint completely straight (Fig. 2).
The splint must be worn continuously for 6 weeks. The tip of the finger must be exercised three or four times per day to rebalance the lateral bands. Mild stiffness is sometimes encountered when the splint is removed. However, this typically resolves with little or no formal hand therapy. For fingers that have developed stiffness, hand therapy may be needed to regain joint flexibility prior to the 6 week splint regimen. Therefore, early assessment and treatment improves the outcome and reduces rehabilitation costs.
The volar plate injury actually occurs in association with dislocations of the middle joint (Fig. 3). Many of us have seen or heard of athletes who have “popped” their finger back into place. When the finger is “popped back in,” or relocated as it is referred to, the finger may in fact be quite stable and little more than buddy taping the finger to an adjoining finger is necessary. However, when the volar plate is torn, the finger may not remain relocated and it can “pop back out.” The joint is now unstable and needs formal intervention to regain stability. Most cases can effectively be treated with splints that will block extension while allowing the person to bend the finger. This splint is typically fabricated for the patient, and the treatment program of flexion movements and splinting is supervised weekly by a hand therapist for progressive correction of finger posture (Fig. 4). Surgery is occasionally indicated and does require a vigorous hand rehabilitation program to restore finger function.
The Mallet finger injury is characterized by the dropped finger deformity. The deformity results from a tear in a structure called the terminal tendon and is seen in Figure 5. This is sometimes accompanied by a fracture and then it is termed a bony mallet (Fig. 6).
Either way the treatment is the same. The tip joint of the finger is splinted in full extension for 6 weeks. It may then be necessary to splint at night for another 2 weeks to maintain the corrected posture. While this injury may seem relatively trivial, it is important to correct the deformity to prevent instability of the middle joint from occurring. Mild stiffness of the joint can develop following prolonged splinting. However, this typically responds to home exercise instruction and does not need formal hand therapy.
While many injuries to the finger are relatively minor and present no permanent issue to the athlete, there are more serious injuries that require professional attention by a qualified hand surgery/therapy team. Early diagnosis followed by appropriate splinting and patient education will result in excellent correction of deformity and pre injury function in the vast majority of cases.