FINGER SPRAINS AND DISLOCATIONS
Sprains and dislocations of the finger joints are one of the most common injuries to the hand. The most frequently injured joint is the proximal interphalangeal joint (PIP joint), which is the second closest joint to the fingertip. From a simple “jammed” finger playing basketball to a sudden fall from tripping on the sidewalk, the PIP joint can get bent backwards (hyperextended) causing injury to the supporting structures.
Like most of the joints of the fingers, the PIP joint has three main supporting structures. On each side of the joint there are strong bands of tissue known as the collateral ligaments. These keep the joint from bending sideways. On the palm side of the joint, there is a thick band of tissue known as the volar plate. This keeps the joint from being able to hyperextend. You can test these stabilizers on your own uninjured fingers and feel the resistance to movement. When a joint is forcibly hyperextended, such as when a basketball unexpectedly hits the fingertip, the stabilizers are stretched and sometimes even torn. This injury to the stabilizers and the subsequent pain, swelling and stiffness are what we refer to as a sprain. When the stabilizers are torn completely and the bones of the joint separate and become misaligned, we refer to this as a dislocation.
Judging the severity of a sprain or dislocation is difficult, and any suspicious injury should be evaluated by a qualified health care provider. Not all sprains and dislocations, even when properly realigned, heal normally with simple rest and time.
If a PIP joint is merely sprained, rest, icing and a brief period of splinting are often recommended as initial treatment. When comfort allows, movement of the joint is encouraged to try to counter the stiffening that occurs as the body tries to heal the damaged tissue. Taping of the injured finger to the neighboring uninjured finger (buddy taping) is often done to allow movement with some degree of protection. Caution with high risk activities such as sports is usually needed for at least a few weeks to allow the injured ligaments to heal and re-stabilize the joint. Hand therapy is sometimes required to help regain motion and strength.
If a PIP joint is dislocated, urgent realignment of the joint is required. Although some people are able to successfully realign their own finger with a quick tug, evaluation by a health care provider including the use of x-ray should be considered for all dislocations. Subtle misalignments and even broken bones may be impossible to detect by simple inspection. If a simple dislocation is officially confirmed and realignment of the joint has been achieved, the injury is usually treated similar to a sprain. Soft-tissue injury to the joint is more severe, this can result in a greater degree of swelling and stiffness as well as a longer period of recovery.