• Home

Home > Medical Reference > Patient Education

• Highlights
• Introduction
• Symptoms
• Causes
• Risk Factors
• Prognosis
• Prevention
• Diagnosis
• Treatment
• Surgery
• Resources
• References

Carpal tunnel syndrome

Description

An in-depth report on the causes, diagnosis, treatment, and prevention of carpal tunnel syndrome.

Alternative Names

Repetitive stress injuries

Prevention

Because multiple factors may cause carpal tunnel syndrome, there is no single mode of prevention. Treating any underlying medical condition is certainly important. Simple common sense may help minimize some risk factors predisposing a person to work-related CTS or other cumulative trauma disorders. A patient can learn how to adjust the work area, handle tools, or perform tasks in ways that put less stress on the hands and wrists. Proper posture and exercise programs to strengthen the fingers, hands, wrists, forearms, shoulders, and neck may help prevent CTS.

Corporate Efforts

Many companies are now taking action to help prevent repetitive stress injuries. In a major survey, 84% reported that they were modifying equipment, tasks, and processes. Nearly 85% were analyzing their workstations and jobs, and 79% were buying new equipment. It should be stressed, however, that there has been no evidence that any of these methods can provide complete protection against CTS. The optimal corporate approach, if possible, is to reallocate workers suffering from repetitive stress injuries to other jobs.

Preventing CTS in Keyboard Workers

Altering the way a person performs repetitive activities may help prevent inflammation in the hand and wrist from progressing into carpal tunnel syndrome. For example, replacing old tools with ergonomically designed new ones can be very helpful.

Rest Periods and Avoiding Repetition. Anyone who does repetitive tasks should begin with a short warm-up period, take frequent breaks, and avoid overexertion of the hand and finger muscles whenever possible. Employers should be urged to vary tasks and work content.

A 2001 study conducted by the National Institute for Occupational Safety and Health reported that even taking multiple "microbreaks" (about 3 minutes each) reduces strain and discomfort without decreasing productivity. Such breaks may include the following:

• Shaking or stretching the limbs
• Leaning back in the chair
• Squeezing the shoulder blades together.
• Taking deep breaths

Good Posture. Good posture is extremely important in preventing carpal tunnel syndrome, particularly for typists and computer users.

• The worker should sit with the spine against the back of the chair with the shoulders relaxed.
• The elbows should rest along the sides of the body, with wrists straight.
• The feet should be firmly on the floor or on a footrest.
• Typing materials should be at eye level so that the neck does not bend over the work.
• Keeping the neck flexible and head upright maintains circulation and nerve function to the arms and hands. One method for finding the correct head position is the "pigeon" movement. Keeping the chin level, glide the head slowly and gently forward and backward in small movements, avoiding neck discomfort.

Good Office Furniture. Poorly designed office furniture is a major contributor to bad posture. Chairs should be adjustable for height, with a supportive backrest. Custom-designed chairs, made for people who do not fit in standard chairs, can be expensive. However, the costs are often offset by the savings in medical expenses that follow injuries related to bad posture.

Voice Recognition Software. For CTS patients who must use a computer frequently, a variety of voice recognition software packages (ViaVoice, Voice Xpress, Dragon NaturallySpeaking, IListen) are now available, enabling virtually hands-free computer use.

Keyboard and Mouse Tips. Anyone using a keyboard and mouse has some options that may help protect the hands.

• The tension of the keys should be adjusted so they can be depressed without excessive force.
• The hands and wrists should remain in a relaxed position to avoid excessive force on the keyboard.
• A 2003 study suggested that mouse-use poses a higher risk than keyboard use. Replacing the mouse with a trackball device and the standard keyboard with a jointed-type keyboard are helpful substitutions.
• Wrist rests, which fit under most keyboards, can help keep the wrists and fingers in a comfortable position.
• Some people recommend keeping the computer mouse as close to the keyboard and the user's body as possible, to reduce shoulder muscle movement.
• The mouse should be held lightly, with the wrist and forearm relaxed. New mouse supports (ErgoCat) are also available that relieve stress on the hand and support the wrist.
• Some people cut their mouse pads in half to reduce movement.

Innovative keyboard designs may reduce hand stress:

• Alternative geometry keyboards (Microsoft Natural Keyboard, Apple Adjustable Keyboard) allow the user to adjust and modify hand positions as well as adjust key tension. Most have a split or "slanted" keyboard that places the wrists at an angle. Studies suggest they are useful in promoting a neutral position for the wrist.
• The continuous passive motion (CPM) keyboard lifts and declines gently and automatically every three minutes to break tension on the hands and wrist. A report of a clerical worker with CTS who used this device found an overall improvement of 10 words per minute in the typing tests, a decrease in disability score and symptom severity, and an improvement in function.
• A keyless keyboard (orbiTouch) is an innovative device that uses two domes. The typist covers the domes with his or her hands and slides them into different positions that represent letters.

Reducing Force from Hand Tools

The force placed on the fingers, hands, and wrists by a repetitive task is an important contributor to CTS. To alleviate the effect of force on the wrist, tools and tasks should be designed so that the wrist position is the same as it would be if the arms dangled in a relaxed manner at the sides.

• No task should require the wrist to deviate from side to side or to remain flexed or highly extended for long periods.
• The handles of hand tools such as screwdrivers, scrapers, paint brushes, and buffers should be designed so that the force of the worker's grip is distributed across the muscle between the base of the thumb and the little finger, not just in the center of the palm.
• People who need to hold any tools (including pencils and steering wheels) for long periods of time should grip them as loosely as possible.
• In order to apply force appropriately, the ability to feel an object is extremely important. Tools with textured handles are helpful.
• If possible, people should avoid working at low temperatures, which reduces sensation in hands and fingers.
• Power tools and machines should be designed to minimize vibrations.
• Wearing thick gloves, when possible, may lessen the shock transmitted to the hands and wrists. One 2001 study found, however, that wearing gel-padded gloves clearly increased comfort but did not actually protect against compression-induced CTS.

Hand and Wrist Exercises for Prevention of Carpal Tunnel Syndrome

Hand and wrist exercises may help reduce the risk of developing carpal tunnel syndrome. Isometric and stretching exercises can strengthen the muscles in the wrists and hands, as well as the neck and shoulders, improving blood flow to these areas. Performing the simple exercises described below for 4 to 5 minutes every hour may be helpful.

Exercises for Carpal Tunnel Syndrome
Wrists	Exercise 1. Make a loose right fist, palm up, and use the left hand to press gently down against the clenched hand. Resist the force with the closed right hand for 5 seconds. Be sure to keep the wrist straight. Turn the right fist palm down, and press the knuckles against the left open palm for 5 seconds. Finally, turn the right palm so the thumb-side of the fist is up, and press down again for 5 seconds. Repeat with the left hand.
	Exercise 2. Hold one hand straight up shoulder-high with fingers together and palm facing outward. (The position looks like a shoulder-high salute.) With the other hand, bend the hand being exercised backward with the fingers still held together and hold for 5 seconds. Spread the fingers and thumb open while the hand is still bent back and hold for 5 seconds. Repeat five times for each hand.
	Exercise 3. (Wrist Circle) Hold the second and third fingers up, and close the others. Draw five clockwise circles in the air with the two finger tips. Draw five more counterclockwise circles. Repeat with the other hand.
Fingers and Hand	Exercise 1. Clench the fingers of one hand into a fist tightly. Release, fanning out the fingers. Do this five times. Repeat with the other hand.
	Exercise 2. To exercise the thumb, bend it against the palm beneath the little finger, and hold for 5 seconds. Spread the fingers apart, palm up, and hold for 5 seconds. Repeat five to 10 times with each hand.
	Exercise 3. Gently pull the thumb out and back and hold for 5 seconds. Repeat five to 10 times with each hand.
Forearms (stretching these muscles will reduce tension in the wrist)	Place the hands together in front of the chest, fingers pointed upward in a prayer-like position. Keeping the palms flat together, raise the elbows to stretch the forearm muscles. Stretch for 10 seconds. Gently shake the hands limp for a few seconds to loosen them. Repeat frequently when the hands or arms tire from activity.
Neck and Shoulders	Exercise 1. Sit upright and place the right hand on top of the left shoulder. Hold that shoulder down, and slowly tip the head down toward the right. Keep the face pointed forward, or even turned slightly toward the right. Hold this stretch gently for 5 seconds. Repeat on the other side.
	Exercise 2. Stand in a relaxed position with the arms at the side. Shrug the shoulders up, then squeeze the shoulders back, then stretch the shoulders down, and then press them forward. The entire exercise should take about 7 seconds.

• Review Date: 3/14/2007
• Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial process . A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-2007 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.