Carpal tunnel syndrome is a painful condition affecting roughly 5% of the American adult population and is the most common “compressive neuropathy” that can afflict the hand and wrist. It can be successfully treated in the vast majority of cases but when left untreated can cause severe disability.
It is caused by the median nerve in the wrist being compressed by the carpal tunnel, a passageway on the underside of the wrist that passes into the hand. The median nerve is the uppermost of a series of nerves that pass through the carpal tunnel and is the one most affected by the chronic inflammation that characterizes carpal tunnel syndrome.
This compression causes hand pain, numbness and tingling in the thumb and first two fingers, as well as the radial (thumb) side of the third finger. Other symptoms are a weakening of grip strength and wasting of the muscles at the base of the thumb. This muscle wasting is one of the key diagnostic signs for carpal tunnel syndrome. These symptoms are often more severe at night and can cause disrupted sleep.
Usually, in about 55-65% of cases, both wrists are affected. The severity of carpal tunnel syndrome can vary from mild tingling symptoms in one hand to severe pain and loss of use in both hands. In the UK, females are more than twice as likely to develop the syndrome and to develop it earlier. Typically, CTS will present symptoms in a female between the ages of 45 and 54 years old, while in males it develops usually between 75 and 84 years of age. Pregnant women can develop CTS in late pregnancy but it usually does not remain as a chronic condition, dissipating after pregnancy.
CTS is generally regarded as a “work-related musculoskeletal disorder”, or WMSD, caused by repetitive wrist movements and strain. Another term for this is biochemical overload. This is the reason that CTS occurs more often in manual workers than in other, less physically intensive workplaces and disciplines.
There is an association between CTS and hypothyroidism (a condition where the thyroid gland is under producing), diabetes of all kinds, and rheumatoid arthritis. The reasons for this are, at present, unclear but the association with inflammation in the body and especially the hands is thought to be a contributor. Arthritis is believed to be an autoimmune condition where the body’s immune cells turn from fighting invaders to attacking the body’s own tissues, believing them to be a threat.
One small study with six patients found that carpal tunnel syndrome, in these patients of unknown cause, was a precursor to autoimmune conditions, such as rheumatoid arthritis. This link, while tenuous and needing more research, could suggest a possible link between a “faulty” immune system and the onset of carpal tunnel syndrome and a potential early symptom for the disease. This might account for the onset of the condition in females during the time they are most likely to start the menopause, which is strongly related to changes in the immune system. Estrogen appears to play a role in the development and maintenance of a strong immune system and the relatively sudden withdrawal of large quantities of estrogen during menopause is currently under some scrutiny for its effects on autoimmune conditions.
When an immune response is launched by the body, whether against a pathogen or mistakenly against the body’s own tissues in an autoimmune attack, one of the consequences is inflammation. This is very helpful for increasing the temperature of the tissue to help kill bacteria, for targeting and containing pathogens and directing an adequate response.
This inflammatory response is essential but when it goes wrong, can cause lots of problems. One such is carpal tunnel syndrome. When there is a general immune response or raised level of immune cells in the blood, tissues that are already under strain such as the carpal tunnel have a higher level of inflammation anyway. With a flood of inflammation “factors”, as they are known, this high base level of inflammation goes through the roof, causing the tissues to expand in response and press down on the median nerve. The body behaves like it is under attack but it is, in fact, causing the symptoms itself. This is the current thinking on CTS as an immune disorder.
Poor circulation is a closely related to carpal tunnel syndrome, with the inflamed nerve sheath pressing on blood vessels and reducing the amount of blood that can flow. The pressure from the blood can increase the inflammation in the carpal tunnel and lead to a worsening cycle of symptoms. Poor circulation can cause nerve damage, pain, and discomfort, as well as a loss of feeling.
First of all, relating to the autoimmune theory, the onset of CTS can be seen as an indicator of further autoimmune or inflammatory conditions such as rheumatoid arthritis, hypothyroidism, systemic lupus and more. Many conditions like MS, Parkinson’s and type 1 diabetes are being found to have increasing amounts of evidence for them being auto-immune related, whether due to an overreaction to infection or a reprogramming of the immune system. This isn’t well understood but is the focus of intense research. The presence of carpal tunnel syndrome as an early indicator of problems with the immune system could be a potential lifesaver, or life quality saver, as it can lead to further testing and potential treatments earlier than would otherwise be possible. This is not well explored so anyone thinking they might be developing the condition shouldn’t panic, consult their doctor and see what they say.
More immediate consequences of CTS include a person not being able to work, exercise, play sports, engage in hobbies, the list goes on. As this counts as about 1 in 20 Americans, the cost to society and the individual are immense. The NCBI estimated in 1995 that the cost to the economy alone was over $2 billion. Fast forward 20 years and the cost will be much higher. Partly this was due to the compensation for workers but the loss to the economy from their production was the biggest factor.
A later study by the same group found that after developing CTS, workers are earning roughly half of what non-CTS workers are earning or a loss of up to $80,000. While surgery helped in many cases, the burden to the economy, their families, and lifestyles from CTS was enormous. Periods of unemployment are related to higher rates of ill health, depression and lower wages in the future, especially in women.
The personal costs of carpal tunnel syndrome are multiple and severe. Being out of work has a clearly negative effect on the individual, but the physical limitations are more pernicious. When someone finds themselves unable to open a jam jar or hold a book to read because their hands are, they can find this very upsetting, not to mention limiting. The pain can be quite severe, as can the pins and needle and numbness. For everyday tasks such as typing, using a mobile phone, brushing teeth, cooking or cleaning, carpal tunnel syndrome can have a marked impact, making some of them impossible.
Disrupted sleep is a major factor in both a reduced quality of life and a higher risk of mortality from heart disease, car accidents, and reduced cognitive ability. Carpal tunnel syndrome symptoms regularly occur more severely at night and can regularly wake patients. When this occurs over a lengthy period, it can have severe consequences on the quality life and health of the patient.
This is a less recognized form of disability, and while in many Western countries the compensation available can be adequate for a decent standard of living, many people around the world have no insurance that would cover CTS and are therefore at risk of destitution. The availability of treatment is not complete or widespread in many countries and indeed is far beyond the means of many. The most immediate consequence of this is unemployment, but the wider consequences can be children not having enough to eat because the breadwinner cannot work, missing out on vital education, medical costs and more. Children who miss education because they have to work in the place of a disabled parent or carer are much more likely to face a cycle of poverty than those that get a good standard of education. Carpal tunnel syndrome is one of the most common causes of disability but one rarely mentioned in the news or assessed for its impact. There have been no studies this author could find where the link to poverty was discussed, so the above reasoning is based on the effects that the related symptoms of CTS cause in other diseases.
Clearly, this is an area that needs more attention. While in many cases the symptoms of CTS are not debilitatingly severe, when they are untreated they can result in permanent nerve damage. This can put someone out of economic production for good, and in poorer demographics and countries, where menial work is most common, CTS can be a direct route to poverty. Further study and awareness can make this significant relationship more known.
There appears to be a strong genetic factor in the development of carpal tunnel syndrome, with roughly 25% of people who develop the condition having a family member who also has CTS. This is poorly understood, however, and so far, no genes have been reliably related to the syndrome.
When a family member is diagnosed with CTS, it is worth getting other family members tested. Early treatment can avoid some of the more severe symptoms and ensure a more successful recovery for the individual. Further research should be able to identify the genes involved in a higher risk and people can therefore understand the associated risks and contributing factors, enabling them to modify their lifestyle to avoid the condition.
As discussed above, there is a strong link between CTS and other conditions. If someone suffers from any of the following, they should also consider looking at whether they have any carpal tunnel syndrome symptoms and getting them checked out. If CTS develops, these diseases could be linked, so getting tested for them could help with an early diagnosis.
A difference in the structure of the wrist, whether from birth or due to an accident and healing process, can be a cause of carpal tunnel syndrome. Some people have naturally narrow carpal tunnels, meaning the level of inflammation needed to develop the condition is lower than normal.
Cysts, ganglions, tumours or growths around the carpal tunnel can cause it to become depressed or inflamed and cause the symptoms of CTS.
As the underlying causes of CTS are barely understood, it is very difficult to establish what should be done to avoid developing it. Clearly, avoiding menial labour or wrist intensive work would reduce your risk but that is hardly feasible for many people. If a family member has developed the condition, it is worth assessing your own risk and what you could do about CTS if it were to emerge.
Carpal tunnel syndrome is related to the overwork of the wrist, so by taking regular breaks from hand-based work such as typing or physical labour can help.
Obesity is commonly related to CTs and by losing weight, you not only reduce your risk of dozens of life-threatening conditions but also of carpal tunnel syndrome. Losing weight is also a successful part of alleviating symptoms when CTS does develop.
The widely used initial test to diagnose carpal tunnel syndrome is a light tap to the affected wrist(s). If this produces numbness or tingling in the affected hand, this is a sign of the condition. A similar test requires the wrist to be moved in a circular motion for about a minute. Again, if numbness or tingling is felt, there is a chance it is CTS.
Sometimes a physician can suspect conditions like a trapped nerve in the spine (cervical neuropathy) as the cause and order further tests. These can include electromyography and nerve conduction assessments. These use electrical pulses to measure the reactions of the muscles or nerves respectively to see if there is any permanent damage. A slow signal indicates damage or compression to the nerve sheath.
Carpal tunnel syndrome generally goes away in less than 6 months as the underlying inflammation is reduced. By treating the associated condition (see above), CTS can be relieved in most cases. In long-lasting and severe cases, however medication or surgical treatment can be the only option.
For mild to moderate cases of CTS, wearing a wrist splint reduces pressure on the wrist and can allow the inflammation to go down. The regular movement in a wrist, especially in a menial job, can mean that any opportunity for the wrist to heal is missed, leading to a worsening of symptoms and leading to permanent damage. A wrist splint can prevent this in many cases and is especially helpful at night when the wrist might be placed unwittingly in uncomfortable positions.
Wrist splints are available at many pharmacies and can be obtained on prescription. Consult your physician for advice as to the right kind for you before you buy as the wrong one might exacerbate your condition.
There is a family of steroids called corticosteroids that can help with carpal tunnel syndrome. Corticosteroids have the effect of reducing inflammation on the body and are found to be helpful with CTS. An injection of corticosteroids usually brings relief from symptoms but the underlying causes of the inflammation might not have been treated so symptoms may reoccur. It is unwise to take corticosteroids for a lengthy period of time as there are side effects including diabetes, cataracts, compromised immune system, obesity and more, so eventually, the treatment cannot be continued. When this is the case, usually surgery is the last option.
Simply a term for changing your habits, by modifying your behaviour you can lessen the risks of the condition getting worse. This involves avoiding things that you know make the condition worse. This can be difficult due to the wide range of activities that this can include, but in order to halt the progression of CTS and promote healing, the wrist needs to have as little movement as possible. Currently, there is little evidence that “ergonomic” devices work for CTS but they are unlikely to do any harm if they make you more comfortable.
Behavioural modification can be very difficult for many people as their jobs involve heavy use of the hands. Cooking, cleaning, building, driving, it can all make the condition worse or not improve fast. A comprehensive health insurance plan can provide the cover needed to receive treatment and recover in good time. Without savings or insurance, many people will struggle to modify their behaviour and run the risk of making the condition much worse, even causing permanent damage.
Most cases of severe carpal tunnel syndrome can be treated to some degree by surgery. The surgery offered is routine and relatively low risk, though it usually requires a general anesthetic, which carries a risk of mortality.
Surgery for CTS involves cutting the ligament and sheath around the median nerve to allow the inflamed tissue space to expand. This can be done from through the skin above the nerve directly or via an endoscope, a long, flexible tool inserted into a small incision in the palm that can release the nerve. Endoscopic surgery is less invasive and has a lower recovery time, so is generally preferable though not always possible. Both procedures have about the same success rate.
Three-quarters of patients treated by the NHS rated their recovery as a complete success, a relatively high rate for invasive surgery, especially on nerves.
The risks of surgery cannot be ignored, including infections, nerve damage, pain and bleeding. Also, in a relatively small number of cases, the symptoms return. Recovery from surgery can take a couple of days for an endoscopic procedure or a few weeks for invasive surgery. Due to muscle wastage and nerve damage, it can take 6 months or more for some patients to recover full functioning in their wrists and hands.
After surgery, follow the physician’s instructions as to the use of your hands. Recovery times can vary between patients so only return to work or play sports like squash or tennis when you have been checked by your doctor.
If you think you have Carpal Tunnel Syndrome, don’t worry, most cases will go away within 6 months. Even when it does develop into a more severe case of CTS, there are very successful treatments available. Although you might think it can go away on its own, consultation with a doctor can rule out other causes and prevent a worsening of symptoms and the associated permanent damage that can occur. If in doubt, talk to your doctor.
Any numbness or tingling in the fingers can be a sign of a number of neurological conditions and should always be reported to a doctor. Consult your doctor, they will do a non-invasive test to diagnose the condition and have plenty of advice on the correct course of action if it is indeed CTS. Most insurers have CTS covered in their policies, but it is certainly worth checking and updating if it is not included.
The prospects for carpal tunnel syndrome sufferers is much better than it used to be, and most people can resume a normal lifestyle in weeks or months after the onset of symptoms or surgery.