Carpal Tunnel Syndrome Part 2: Treatment and Prevention

The carpal tunnel is a narrow passageway in the wrist that the median nerve passes through. The median nerve provides sensation to the palm side of the thumb, index and middle fingers. It also carries nerve impulses to the muscles of these digits to bring about movement.   Carpal tunnel syndrome (CTS) occurs when the median nerve becomes compressed or 'pinched' in the carpal tunnel. Last week we looked at what caused CTS and how it is diagnosed.  This week we'll look at ways of treating CTS, and better yet, how it may be prevented.
 

How is carpal tunnel syndrome treated?

The decision of how best to treat CTS depends on a number of factors----the severity of symptoms, the duration of the problem, and what's causing CTS. Non-surgical as well as surgical treatments are available for treating CTS. In most cases, non-surgical options are employed initially, with surgery being reserved for severe cases or those that don't respond to conservative measures. If CTS occurs in someone with medical problems such as diabetes or rheumatoid arthritis, the first step is make sure that the condition is being managed as well as possible. When CTS accompanies pregnancy, symptoms usually resolve after delivery.

What non-surgical treatments are available?
 
Of the non-surgical treatments, the ones most commonly employed are resting/splinting and use of corticosteroid medications. Initial treatment generally involves resting the affected hand and wrist for at least 2 weeks, avoiding activities that may worsen symptoms, and immobilizing the wrist in a splint to avoid further damage from twisting or bending.  The best type of splint holds the wrist in a neutral (unbent) position. This serves to maximize the opening of the carpal tunnel, reducing pressure on the median nerve.  Wearing the splint continuously, both day and night, for a period of time appears to be more effective than just wearing it at night.

If splinting and rest are not effective, use of a corticosteroid (e.g. prednisone), either taken by mouth or injected into the carpal tunnel is often the next step in treatment. Corticosteroids, are potent anti-inflammatory medications and help by shrinking inflamed tissue surrounding the carpal tunnel.  Other non-surgical treatments include taking nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen and physical therapy measures such as ultrasound and mobilization exercises.

What if non-surgical treatments don't help?

If several months of non-surgical treatment has been unsuccessful and the diagnosis has been confirmed, surgery becomes a reasonable option.  A carpal tunnel release involves cutting a band of tissue (carpal ligament) at the wrist to reduce pressure on the median nerve. The traditional procedure requires an incision up to two inches in length on the wrist. A newer endoscopic method is done through one or two small incisions. Although complete recovery can take months, CTS symptoms rarely recur following surgery.

Can Carpal Tunnel Syndrome be prevented? 

Although proof of measures to prevent CTS is lacking, the American Academy of Family Physicians has offered the following suggestions to help avoid developing CTS:

• Lose weight if you're overweight
   
• Get treatment for any disease you have that may cause carpal tunnel syndrome.
   
• If you do the same tasks with your hands over and over, try not to bend, extend or twist your hands for long periods.
   
• Don't work with your arms too close or too far from your body.
   
• Don't rest your wrists on hard surfaces for long periods.
   
• Switch hands during work tasks.
   
• Make sure your tools aren't too big for your hands.
   
• Take regular breaks from repeated hand movements to give your hands and wrists time to rest.
   
• Don't sit or stand in the same position all day.
   
• If you use a keyboard a lot, adjust the height of your chair so that your forearms are level with your keyboard and you don't have to flex your wrists to type.

Carpal Tunnel Syndrome Part 1: Symptoms, signs and diagnosis

The carpal tunnel is a narrow passageway in the wrist that the median nerve passes through. The median nerve provides sensation to the palm side of the thumb, index and middle fingers. It also carries nerve impulses to the muscles of these digits to bring about movement.   Carpal tunnel syndrome (CTS) occurs when the median nerve becomes compressed or "pinched" in the carpal tunnel.  In today's Health Tip we'll look at the causes for the development of CTS and how CTS is diagnosed.  Next week's discussion will be on the treatment and prevention of CTS.

What causes carpal tunnel syndrome? 
Rather than being a disease of the nerve itself, CTS is caused by conditions that impinge on the median nerve.   Someone with a congenitally narrowed carpal tunnel would be especially prone to developing CTS.  Conditions that cause swelling of the tissue surrounding the canal with resulting narrowing can cause CTS also. These include injury, inflammation, repetitive activities of the hand and wrist, and arthritis.

What are the symptoms of carpal tunnel syndrome?
 Symptoms associated with CTS include burning, tingling, or numbness in the thumb, index, and/or middle finger. Often, the symptoms first appear during the night, since many people sleep with bent a (flexed) wrist which functionally narrows the carpal tunnel.  As CTS progresses people experience tingling during the day, especially with certain activities such as keyboarding or operating machinery. Decreased
grip strength may make it difficult to form a fist, grasp small objects, or perform other manual tasks.  In chronic and/or untreated cases, the muscles at the base of the thumb may waste away.

Who gets carpal tunnel syndrome?   
For the most part, CTS is a disease that affects adults.  Genetic factors which affect the structure of the hands and wrists have been shown to be more important in the development of CTS than repetitive hand use or other occupational factors.  Women are three times more likely than men to develop the condition, perhaps due to having smaller carpal canals than men.  Those with diabetes, rheumatoid arthritis and pregnant women are also at increased risk.  CTS is especially common in those performing assembly line work such as sewing, finishing, cleaning, and meat packing.   Although keyboarding is frequently blamed for causing CTS, one study found no increased risk of developing CTS among a group of individuals using their computers up to 7 hours per day.

How is Carpal Tunnel Syndrome diagnosed?
Awakening with hand numbness in the distribution of the median nerve is a hallmark of the disease.  Activity-related wrist pain or numbness in the little finger is not.  Activities that produce symptoms, such as holding a telephone or gripping a steering wheel also suggest the possibility of CTS. The physical exam can reveal important clues to the diagnosis also. Tapping on the median nerve at the wrist or bending the hand toward the wrist can sometimes reproduce the patient's symptoms. In many cases, electrical testing of median nerve function is done to help confirm the diagnosis.  Electrodiagnostic testing includes the electromyogram and nerve conduction velocity (NCV).   When performing an electromyogram, needles are inserted into muscles to measure the electrical activity of these muscles at rest and during contraction.  For the NCV, electrodes are placed on either side of the carpal tunnel.  The speed of small shocks passed through the median nerve is then assessed. Slowing of the electrical impulse confirms the presence of CTS.  In addition to confirming the diagnosis, electrodiagnostic studies can also help in determining the best treatment option.

Please note an error in last week's Health Tip on breast cancer screening.  In regard to the recommendations for screening in women age 50 to 75, the United States Preventive Medicine Task Force (USPMTF) currently recommends that mammograms be performed every 2 years.  The statement that "The current evidence is insufficient to assess the balance of benefits and harms of screening" is the USPMTF position on screening women over the age of 75.  Note that both the USPMTF as well as the American Cancer Society recommend the use of screening mammograms in this age group of women, although the recommended interval differs.

Breast Cancer Screening - Conflicting Guidelines, Common Goals

Two of the leading organizations issuing guidelines for cancer screening, the United States Preventive Services Task Force (USPSTF) and the American Cancer Society (ACS), have separately made recommendations for the early detection of breast cancer.  In both cases, data from current research was analyzed and compiled to develop their recommendations.  Not surprisingly, when analyzing complicated research with unanswered questions about a disease, somewhat different conclusions were reached regarding certain aspects of breast cancer screening.  Despite these differing opinions, both groups are acting in the best interest of women and are committed to helping to reduce breast cancer deaths.  All of the authorities on the subject also agree that additional research will be necessary to help clarify and refine these recommendations.

The ACS recommendations come from a 2014 review of the topic and apply primarily to women without breast cancer symptoms who are at average risk for the development of breast cancer.   The USPSTF recommendations are in draft form currently, pending final review.  Their recommendations apply to women age 40 or older who do not show signs of breast cancer, have not been diagnosed with breast cancer previously and who are not at high risk for the development of breast cancer.

Screening Recommendations for Women in their 20s and 30s
 
            ACS:   "For women in their 20s and 30s, it is recommended that clinical breast examination be part of a periodic health examination, preferably at least every three years.  Beginning in their 20s, women should be told about the benefits and limitations of breast self-examination (BSE). The importance of prompt reporting of any new breast symptoms to a health professional should be emphasized. Women who choose to do BSE should receive instruction and have their technique reviewed on the occasion of a periodic health examination. It is acceptable for women to choose not to do BSE or to do BSE irregularly."
            USPSTF:  The most recent recommendations did not address this age group of women.

Screening Recommendations for Women between 40 and 49
 
            ACS:  "Women age 40 and older should have a mammogram every year and should continue to do so for as long as they are in good health."  Along with screening, the ACS believes that "women should have an opportunity to become informed about the benefits, limitations, and potential harms associated with regular screening."

            USPSTF:   The USPSTF does not recommend screening mammograms in this age group of women.  While they are aware of some research indicating that mammography screening can be effective in women in their 40's, the USPSTF believes that "The decision to start screening mammography in women before age 50 years should be an individual one. Women who place a higher value on the potential benefit than the potential harms may choose to begin screening between the ages of 40 and 49 years."  Potential harms from breast cancer screening include overdiagnosis and false-positive test results.  Overdiagnosis occurs "when a woman is diagnosed with, and receives treatment for, breast cancer that would not become a threat during her lifetime".  False positives occur when a test indicates has breast cancer when not actually present. This can lead to unnecessary anxiety and invasive procedures, such as breast biopsy.

Screening Recommendations for women ages 50 to 75
 
            ACS:  "Mammograms should be continued regardless of a woman's age, as long as she does not have serious, chronic health problems such as congestive heart failure, end-stage renal disease, chronic obstructive pulmonary disease, and moderate to severe dementia."

            USPSTF:  "The USPSTF recommends screening mammography every two years"

Both groups agree that screening for early breast cancer with mammograms is particularly applicable to women in the 50 to 75 year age groups, although there is disagreement as to the screening interval.  To complicate things further, other medical groups have offered their own screening recommendations. The American Congress of Obstetricians and Gynecologists and the American College of Radiology recommendations follow closely to the ACS guidelines while recommendations from the Canadian Task Force on Preventive Health Care are similar to those of the USPSTF.

These recommendations relate to women who are of average risk.  Having a parent, sibling, or child with breast cancer, a genetic mutation (such as BRCA), or a history of receiving chest radiation at a young age increases one's risk of developing breast cancer.  These situations should be handled individually and may call for more specialized screening strategies such as shorter screening intervals or the use of other tests, such as breast MRI.

While it may seem troubling that there is no consensus among experts, it is important to note that the development of screening guidelines is an ongoing process with new research updating and refining the criteria along the way.  When there are questions regarding your personal situation, a discussion with your doctor is a good way of determining how you will approach breast cancer screening.