Mallet or baseball finger is a common finger injury that occurs during ball handling sports. The injury occurs when the fingertip is hit by the ball or by another player and the finger is forcefully bent at the last joint of the finger. There is pain on the top of the finger behind the nail and the athlete is unable to straighten the end of the finger up.
In most cases, the injury ruptures the tendon that straightens the tip of the finger. The degree of deformity is related to the degree of tendon injury. Sometimes the tendon may be connected to a piece of bone with a fracture that involves the joint.
To confirm the diagnosis a classic history of being struck in the tip of the finger with a ball and an x-ray are all that is needed. The x-ray identifies any associated bony injuries and helps to determine if the joint is partially dislocated or subluxed.
If the injury involves the tendon alone splinting the finger joint in full extension for six weeks is the recommended treatment. After six weeks the splint is removed and motion exercises are started. If the finger joint begins to droop again the splint is left on for an additional two weeks and motion delayed.
Some patients will not go to see the orthopedist for treatment immediately and initial treatment should be to immobilize the finger for eight weeks at this point. It is critical that during the splinting treatment that the finger not be allowed to bend or the treatment must be restarted from the beginning again. Movement is allowed at the joint in the middle of the finger throughout treatment and in fact encouraged to prevent stiffness. In most cases continued sports participation is allowed with the splint.
If the injury involves a fracture treatment will be determined by the size of the bony fragment and whether the joint is subluxed. Fractures, which involve more than 30% of the joint surface, may be unstable. In cases when the joint is unstable surgery with temporary pinning of the fracture and joint are required. Injuries treated with surgery tend to be stiffer and may develop wound issues.
After completion of the initial splinting program a skilled hand or occupational therapist is needed to restore motion and return the finger to a healthy state. This is especially true in injuries that require surgery. A splint will often be worn at night for a month to prevent recurrence of the deformity.