What is Mallet Finger?
Mallet finger, also known as baseball finger, occurs when the tendon that straightens the end joint of a finger or thumb is injured. This joint is known as the distal interphalangeal (DIP) joint in the fingers and the interphalangeal (IP) joint in the thumb. The injury typically results from a forceful impact to the tip of the finger or thumb, causing the digit to bend further than it normally would. Consequently, the affected finger or thumb cannot be straightened without assistance, resulting in a characteristic droop.
Anatomy of the Finger
Tendons are robust tissues connecting muscles to bones, essential for movement. The muscles controlling finger and thumb movements are located in the forearm and hand. Tendons extend from these muscles through the wrist and attach to the finger and thumb bones.
- Extensor Tendons: Located on the top of the hand, these are responsible for straightening the fingers.
- Flexor Tendons: Located on the palm side, these enable the fingers to bend.
Causes of Mallet Finger
Mallet finger usually occurs when a rigid object, like a ball, strikes the tip of a finger or thumb, forcing it to bend beyond its normal range. This force can tear the tendon at the last joint of the digit. While a significant force is typically needed to cause this injury, minor actions like tucking in bed sheets can sometimes result in mallet finger.
The injury can either tear the tendon or pull it away from its attachment point on the finger bone (distal phalanx). In some instances, a small piece of bone is pulled away with the tendon, known as an avulsion injury. Larger avulsion fractures may cause joint instability, necessitating surgery.
Symptoms of Mallet Finger
- Pain, swelling, and bruising of the affected finger.
- Drooping of the fingertip.
- Inability to straighten the fingertip without manual assistance.
Risk of Infection
Immediate medical attention is necessary if there is blood beneath the nail or if the nail is detached, indicating a potential cut in the nail bed or a fracture extending to the bone (open fracture), increasing the risk of infection.
First Aid for Mallet Finger
- Apply ice to the finger to reduce pain and swelling.
- Keep the hand elevated above heart level.
- Use acetaminophen or NSAIDs like ibuprofen for pain relief.
- Create a well-padded splint for the tip of the digit, ensuring it does not restrict the movement of uninjured joints.
- Seek evaluation by a hand surgeon as soon as possible, ideally within a week of the injury.
Medical Examination and Diagnosis
A doctor will conduct a physical examination and may order X-rays to assess the extent of the injury. X-rays can reveal if a fragment of the distal phalanx was pulled away or if there are other fractures that may need surgical correction.
Treatment Options
Nonsurgical Treatment:
- Splinting is the primary treatment, holding the fingertip straight for 6 to 8 weeks.
- The splint must be worn continuously, including during bathing, to prevent disruption of healing.
- Follow-up visits with the doctor will monitor progress and manage any skin irritation from prolonged splint use.
Surgical Treatment:
- Considered if there is a large avulsion fracture or if the joint is out of alignment.
- Surgery may involve using pins to hold the bones in place while they heal.
- For chronic mallet finger injuries, joint fusion may be an option to create a permanent, stable position.
Recovery and Prognosis
With proper and prompt treatment, most patients with mallet finger recover well. Even if treatment is delayed, many cases still achieve good outcomes. However, adherence to the prescribed treatment regimen is crucial for optimal recovery and function.
Understanding the causes, symptoms, and treatment options for mallet finger allows individuals to manage their injuries effectively and return to their normal activities safely. If you suspect a mallet finger injury, seek medical advice promptly to ensure the best possible outcome.
