Description
The extensor tendons, which are located on the back of the hand, allow individuals to straighten the thumb and fingers. These tendons originate from the muscles in the forearm. The tendons become thin and flat as they continue on into the fingers of the hand. It is these small tendons that allow for coordination and delicate finger motions. Extensor tendons are located just beneath the top surface of the skin, directly on the bone, and on the back of the fingers and hands. Due to their location, these tendons are often injured.
A mallet injury occurs when an object hits the tip of the finger or thumb, and the force of the blow tears the extensor tendon. Occasionally, a minor force such as tucking in a bed sheet or jamming a finger could cause a mallet finger. After an injury of this type, it may prove difficult to straighten one or more of the finger joints. The injury may pull the tendon away from the place where it attaches to the finger bone (distal phalanx) and in some cases, a small piece of bone is pulled away along with the tendon. This is called an avulsion injury.
Symptoms
- Pain
- Swelling
- Bruising
- Fingertip drooping- inability to straighten finger without assistance
Causes
- Object such as a ball strikes the tip of the finger or thumb
- Jamming a finger
- Tucking in a bed sheet
Risk Factors
- Sports that require a ball (baseball, softball, football, basketball, rugby, volleyball)
Prevention
- Use caution when participating in physical activities
- To prevent the same mallet finger from reoccurring, wear the splint for the entire duration of time that was recommended by the doctor.
Diagnosis
- Your doctor will discuss your symptoms, review your medical history and complete a physical examination of the injured finger.
- During the examination, your doctor will hold the affected finger and ask you to straighten it on your own. This is called the mallet finger test.
- X-ray: X-rays are necessary to determine if a fragment of the distal phalanx was pulled away when the tendon ruptured, or if there is a larger fracture of the bone. An x-ray will also show whether the injury pulled the bones of the joint out of alignment.
Treatment
- Most mallet finger injuries can be treated with splinting, however there are surgical options for more severe cases. Mallet fingers that go untreated can result in deformity and stiffness of the affected finger joint.
- The most common treatment for a mallet finger is to place the finger in a splint, at all times, for approximately six weeks. The splint will secure the finger in a straight (extended) position, allowing the torn tendon to properly heal in appropriate position. Upon removing the splint, the patient’s injured joint is usually stiff and mobility is limited. The finger will gradually regain flexibility over time. Surgical intervention is rarely needed unless bone fragments are present.
- If a large fracture fragment is present or the joint is misaligned, a surgical repair may be considered. In these situations, pins are inserted to hold the pieces of bone together as the tendon heals.
- Temporary pins may also be inserted if the patient is struggling with a splinting regimen. Temporary pins will remain for about 8 weeks.
Complications
- Full extension of the fingertip is not regained.
- Patient struggles with following recommended splinting regimen
Outcomes
- Splinting treatment usually results in both acceptable function and appearance, however, many patients may not regain full fingertip extension.
- If mallet finger injuries are left untreated, it may result in stiffness and deformity of the injured fingertip.
