Finger injuries: 5 cases to test your skills

Some finger injuries require little more than icing; others are more serious, often emergent, conditions with outcomes that are dependent on an accurate diagnosis and rapid initiation of treatment.

The 5 cases that follow describe injuries with varying degrees of severity. Read each case and select the multiple-choice answer you think is most appropriate. Then read on to find out if you were right—and to learn more about the clinical presentation, diagnosis, and treatment for each type of injury.

CASE 1 A 45-year-old auto body worker walks into your office at 5:30 pm, just as your staff is closing up for the day. A few hours ago, he reports, he was spray-painting a car with a paint gun when he felt a sudden pain in his right index finger. His immediate thought was that he had torn something, but the pain quickly subsided. So he continued to work—until about 45 minutes ago, when the pain became so intense that he knew he needed medical care right away.

Examination reveals redness and increased skin temperature on the radial palmar side of the proximal interphalangeal (PIP) joint of the index finger. Two-point discrimination is decreased to 10 mm, vs 5 mm on the same finger of the opposite hand. The patient can flex his PIP and distal interphalangeal (DIP) joints but complains of pain and stiffness. You obtain x-rays of the injured
finger (FIGURE 1).

WHAT'S YOUR NEXT STEP?

Answer: Send the auto-body worker to the nearest ED and call ahead (A).The risk for amputation of a finger with a high-pressure injection injury is high, unless aggressive surgical debridement is done within 6 hours.

This patient sustained a high-pressure injection injury to the PIP joint of his right index finger. The patient’s description of how the injury occurred suggested this, and the radiograph confirmed it by showing some paint under the skin (See arrow, FIGURE 1). Such injuries occur when a high pressure (typically from a hose) forces air or a substance—eg, diesel fuel, paint, or solvent—through the skin into the finger.

Although high-pressure injection injury often has a benign presentation, it is actually a medical emergency. If aggressive surgical debridement does not occur within a 6-hour window, the patient runs a high risk for amputation of the digit.¹ A hand surgeon should be contacted as soon as possible.

The severity of the injury varies, depending on the amount of pressure (amputation rates are as high as 43% when the pressure per square inch >1000), the type of material injected (diesel fuel is the most toxic), and the location.^1,2

Instruct the patient to remove any jewelry, such as a wedding band or watch, on the affected hand or wrist, and to keep the hand elevated. Broad-spectrum antibiotics should be started right away, and a tetanus booster given, if needed. Do not apply heat or use local anesthesia, as both can increase the swelling.²

CASE 2 A 17-year-old cheerleader comes to see you on Monday afternoon, after injuring her left pinky during a Friday night game. The patient, who is right-handed, points to the left PIP joint when you ask where it hurts, and tells you that the finger is stiff. She has been icing it since the injury occurred, to make sure she is ready to cheer by next weekend.

The injury occurred when she was spotting another cheerleader during a routine, the patient reports, adding that the pinky was “dislocated.” The coach “popped” it back in place and buddy-taped the injured finger to her ring finger.

The patient is able to flex and extend the DIP joint on the pinky when the PIP joint is stabilized. She can also flex the PIP joint unassisted, but has difficulty extending it. The digit demonstrates slight flexion of the PIP joint. You note tenderness over both collateral ligaments and the dorsum of the PIP joint, but not over the volar aspect of the injured finger, and order x-rays (FIGURE 2).

WHAT'S YOUR NEXT STEP?