Repetitive Strain Injury Trigger Finger

What is Trigger Finger?

Trigger finger is a form of repetitive strain injury (RSI) in which the tendon in the thumb swells or is unable to freely move due to buildup of scar tissue in the tunnel where the tendon resides. This swelling and lack of movement is generally accompanied by pain and a crackling sound when a person with trigger finger tries to straighten his fingers. Typically, trigger finger affects more than one digit at a time, namely the middle and ring fingers, as well as the thumb.

This form of RSI is known as “trigger finger” because, as you try to straighten the affected fingers, the tendon gets stuck and then quickly pops through the blocked area, causing the fingers to recoil as they would if a person had just shot a gun.

Causes and Risk Factors of Trigger Finger

Although the exact causes of trigger finger are unknown, the following are some risk factors that have been known to contribute to the condition:

  • Age: Those between 40 and 60 are at a higher risk of developing trigger finger.
  • Diabetes: While it’s not known why diabetes contributes to trigger finger, diabetics are more likely to come down with it.
  • Gender: Women are more likely to suffer from trigger finger than men.
  • Hypothyroidism: Like diabetes, the connection between hypothyroidism and trigger finger is known to exist, but the reasons for this connection are still unknown.
  • Occupation: Those who regularly work with vibratory tools, such as a jackhammer, are more likely to develop trigger finger.
  • Rheumatoid Arthritis: RA patients are at a higher risk of developing trigger finger, most likely due to the fact that their joints already contain a fair amount of scar tissue and other blockage.

Symptoms of Trigger Finger

Although a specific injury may set off trigger finger, the development of this condition tends to be far subtler, arising slowly over a period of time like most forms of RSI. Common symptoms of trigger finger include:

  • fingers stuck in a bent position
  • increased stiffness or an intensified “trigger” reaction after periods of inactivity
  • more intense symptoms in the morning
  • pain in the palm of the hand
  • sensations that the joint has been dislocated when the tendon finally pushes through the blockage
  • small lumps throughout the palm of the hand
  • swelling.

As soon as you start experiencing any of these symptoms, seek medical attention. Delaying diagnosis and treatment will only cause the condition to worsen, causing you more pain.

Doctors diagnose trigger finger by examining your hand. Diagnosing this condition doesn’t involve X-rays, as the tissue blockage doesn’t show up on them.

Treatments for Trigger Finger

The method of treating trigger finger depends on how severe the condition is. To minimize the immediate pain, your doctor will likely prescribe you anti-inflammatory medication, such as prescription strength Tylenol or Advil. For more serious cases, doctors may administer a corticosteroid shot, a more intense anti-inflammatory that has faster results.

However, while this does reduce swelling and temporarily relieves pain, it doesn’t treat the root of the problem, the swollen tendon or tissue blockage. As a result, doctors will also prescribe physical therapy, a treatment regimen that works to restore movement, flexibility and functionality to various areas of the body.

Physical therapy for trigger finger may involve:

  • performing certain exercises
  • regular corticosteroid injections
  • therapeutic ultrasound to break up scar tissue and reduce swelling
  • wearing a splint.

If the case of trigger finger doesn’t respond to physical therapy, then surgery may be needed. Surgery for trigger finger is a straightforward, easy procedure that can generally be done on an outpatient basis under local anesthesia. During the procedure, the surgeon cuts the sheath and removes the tissue blockage that hinders the movement of the tendon.

While patients can move their fingers immediately after the procedure, full recovery takes a few weeks. Doctors recommend that patients avoid certain movements and regularly elevate their hand during the recovery period to reduce pain and swelling. In certain cases, patients who get surgery for trigger finger may need to visit a physical therapist after they have recovered in order to regain full mobility of their fingers.

Preventing Trigger Finger

Unfortunately, most people are unaware that they are developing trigger finger until the case is full-blown and they experience painful symptoms. Because those who type, play instruments or perform otherwise repetitive tasks with their hands for extended hours each day are at a higher risk of developing trigger finger (or any repetitive strain injury, for that matter), the best way to prevent this condition is to be sure to warm up your hands before working with them.

Similarly, taking breaks and changing positions throughout the day can relieve some the pressure you put on your hands. For those who work with vibratory tools, wearing anti-vibration gloves can reduce the chances of getting this condition. Because some other medical conditions, such as diabetes and hypothyroidism, can also contribute to the development of trigger finger, keeping these conditions in check and caring for them properly is another good way to prevent trigger finger.

Resource

American Academy of Orthopaedic Surgeons (2007), Trigger Finger (2007). Retrieved June 28, 2007 from: http://orthoinfo.aaos.org/fact/thr_report.cfm?Thread_ID=168