Carpal tunnel syndrome is also known as the compression of the median nerve. This condition is a very common condition that affects people of all ages and races.
This condition causes the patient to experience severe pains, tingling, numbness, and eventual muscle weakness of the wrist and hand.
There is a particular nerve in the arms that is known as the median nerve. The median nerve provides nervous supply and sensations to the lateral three and a half fingers(which includes the thumb, the index finger, the middle finger, and half of the ring finger).
Hence, anything that causes an injury to this nerve; these fingers will not be able to function properly.
The pinky finger, however, may not be quite affected as this nerve doesn’t supply it. It is supplied by another nerve known as the Ulnar nerve.
The discovery of this carpal tunnel syndrome occurred in the mid-1800s, where it was first described. The first surgery that was ever carried out to relieve the effects of this syndrome occurred in the 1930s.
Ever since then, it has become a common condition that is often treated by orthopedic surgeons for over 40years and counting.
What is the Carpal Tunnel?
The Carpal tunnel is a narrow tunnel, canal or tube that is found just in front of the wrist. One can liken it to the tunnel that you drive through using your vehicle.
This carpal tunnel is the one that allows for the passage of the median nerve as well as tendons of muscles into the hand.
These tendons are from muscles that are found in the forearm, and since they are needed for the general movements of fingers, as well as the functionality of the palm, the tendons need as well as the median nerve have to pass through this tunnel to get into the palm.
The carpal tunnel has some components which make it up, and they include:
1. The Carpal bones
The Carpal bones are a set of bones that are found just at the wrist. There are eight carpal bones, which are arranged in two roles; Proximal and distal.
The proximal carpal bones are four, which include scaphoid, lunate, triquetrum, and pisiform bones, while the distal carpal bones include the trapezium, trapezoid, capitate, and hamate.
The arrangement of the carpal bones is in the form of a semi-circle.
2. The ligament
There is a strong ligament that holds the carpal tunnel together, and it is found just at the top of the tunnel; hence, it can be said to sort of form the roof of the tunnel. This ligament is known as the flexor retinaculum.
There are ten structures that are allowed to pass through this very narrow tunnel, and these ten structures include nine tendons and one nerve.
The function of this nerve is to provide sensation to the fingers as well as the palm (except in some cases such as a part of the ring finger and the small finger which are supplied by another nerve).
Asides the provision of sensation, it likewise provides strength to the base of the thumb as well as the index finger.
On the other hand, however, the tendons are rope-like structures that connect the muscles of the forearm to the bones of the hand, and as such, providing the fingers the ability to move and bend at will.
Generally, the median nerve is sandwiched between these tendons, and under normal circumstances, the tendons will not cause the crushing or the squashing of the median nerve.
If for any reason, there is an increased pressure within this narrow tunnel such that these tendons now crush the median nerve, the person will begin to experience the syndrome known as Carpal Tunnel Syndrome.
Causes of Carpal Tunnel Syndrome
Carpal Tunnel Syndrome is caused when there is an increased compression of the median nerve in the carpal tunnel by the tendons that pass through it. Anything that causes the median nerve to become irritated or squeezed may lead to carpal tunnel syndrome.
Often, doctors don’t have an idea as to what exactly causes the irritation or the compression of the median nerve to occur. However, many doctors have attributed the causes to not just one but a combination of several factors.
Some factors that have been considered to be the cause of carpal tunnel syndrome include:
- Repetitive motions: When you are often engaged in conditions that cause you to make repetitive motions such as typing, or any other movements that involve the constant use of your wrist and fingers, then you have the tendency to develop carpal tunnel syndrome.
- Some certain health conditions can cause you to have carpal tunnel syndrome. Conditions such as hypothyroidism, obesity, diabetes, hypertension, or arthritis can cause you to develop carpal tunnel syndrome suddenly.
- A wrist fracture: Wrist fractures that have previously occurred but weren’t well treated or recently occurred can lead to the narrowing of the carpal tunnel and, as such, lead to the compression of the median nerve by the tendons and as such cause irritations causing carpal tunnel syndrome.
Symptoms of Carpal Tunnel Syndrome
The symptoms of Carpal Tunnel Syndrome are often developed over time; however, one may not quite notice it at first. Generally, these symptoms begin gradually, and if not properly treated, will increase into something bigger.
The symptoms that may be experienced include:
1. Numbness or tingling of the fingers and palm
One typical sign that is associated with carpal tunnel syndrome is the tingling of the fingers and general paralysis of the palm and hands. Usually, one will generally experience this tingling in the thumb, the index, middle fingers as well as part of the ring fingers.
The little finger is often exempted from this because it does not receive its nerve supply from the median nerve; instead, it receives sensations from the Ulnar nerve, which is a different nerve altogether.
Often, patients have complained of feeling sensations like an electric shock in their fingers as part of their symptoms. Sometimes, these sensations may travel far up the arm from the wrist, causing general discomfort.
According to research, most patients have complained to have had these symptoms when they are holding the steering wheel while driving, when they wake up from sleep or when they are holding a book or newspaper.
At the beginning of this syndrome, the patient may shake their hands in order to try to relieve themselves of the electric shock sensation, and that often works. However, after a while, these sensations become constant, causing intense hand pain and discomfort.
Once the tingling of the fingers begins to occur continuously, the next symptom which the patient will likely experience is the weakness of the hand muscles. This is because the nerve which supplies them has been crushed, and as such, the muscles begin to grow weak.
Generally, the patient will notice his inability to hold things for long, and as a result, he or she begins to drop objects unconsciously. The patient may also experience that his fingers suddenly go numb on him or her and, as such, causing a lack of sensations in hand.
These are the two common symptoms of Carpal Tunnel. However, there are some other symptoms which may likely occur to the patient, and they include:
- Decreased sensations around the fingertips of the patient.
- Difficulties in doing specific simple tasks such as using small objects, holding a book to read, and so on.
- In severe conditions, the patient will start experiencing a visible decrease in the muscle mass at the base of the thumb, which is often referred to as muscular atrophy.
There are quite a number of risk factors that are attached to Carpal Tunnel syndrome. Although, they may not be directly linked as the causes of this syndrome, however, they tend to increase the chances of one having median nerve irritations as well as compressions.
These factors include;
Research has shown that the occurrence of Carpal Tunnel Syndrome is often more common in women than in men. This may be because the carpal tunnel that is found in women is relatively smaller than that which is located in men.
Some doctors speculate that the length of the carpal tunnel, even among women, is different. Some women generally have a larger carpal tunnel than others.
As such, those women who have a smaller carpal tunnel are likely to experience irritations and compression of the median nerve leading to Carpal Tunnel syndrome.
2. Anatomic factors
There are some certain conditions that indirectly affect the carpal tunnel, and as a result, causing this syndrome, these factors are referred to as anatomic factors.
Factors such as dislocation of the wrist, fracture of the wrist, or any form of arthritis which may deform the small carpal bones that are found in the wrist can ultimately lead to carpal tunnel syndrome.
Also, some people who have a thicker flexor retinaculum can, in turn, lead to the formation of a smaller carpal tunnel causing the compression of the median nerve.
Some conditions can cause inflammation. These conditions are known as inflammatory conditions. Examples of such conditions include rheumatoid arthritis.
Once a patient develops rheumatoid arthritis, the patient will have an inflammatory component that tends to affect the lining of the tendons around the wrist and, as such, putting pressure on the median nerve.
4. Conditions that damage the nerves
There are certain conditions that may cause the nerves to become damaged. Examples of such conditions include diabetes, which can increase a patient’s chances of damaging your nerves, including the median nerve, which will lead to carpal tunnel syndrome.
There are some medications that have been seen to have a direct link to causing carpal tunnel syndromes. Examples of such medications include anastrozole(Arimidex), which is often used to treat breast cancer.
This drug has been seen to have carpal tunnel syndrome as one of its side effects.
6. Physiological conditions
Some physiological conditions, such as pregnancy, can cause the formation of Carpal Tunnel Syndrome.
This is because pregnancy is often associated with retention of body fluids, which can, in turn, lead to the build-up of pressure within the carpal tunnel leading to irritations and compression of the median nerve.
However, after pregnancy, carpal tunnel syndrome tends to resolve itself, and everything goes back to normal. Likewise, another physiological condition that is often associated with carpal tunnel syndrome is menopause.
7. Pathological conditions
Unlike physiological conditions, there are some medical conditions that can relatively lead to Carpal Tunnel syndrome. These conditions include kidney failure, lymphedema, as well as thyroid disorders.
8. Workplace factors
There are some factors that can cause carpal tunnel syndrome, which is often as a result of the type of tools used regularly at one’s workplace.
For those who work at places using heavy machinery, having to work all day with vibrating tools or on an assembly line that requires the prolonged and repetitive flexing of the wrists can cause the build-up of pressure within the carpal tunnel leading to Carpal Tunnel syndrome.
Also, those who work in extremely cold environments have been seen to develop carpal tunnel syndrome often. Research has speculated that this could be because the extreme temperatures have resulted in the irritation of the median nerve.
How then can Carpal Tunnel Syndrome be treated?
The treatment of carpal tunnel syndrome largely depends on how fast it is treated after symptoms occur.
For this article, we would divide treatment into three stages:
1. The mild or early stages
Once a person notices the signs of this defect at the early stages, he or she can do the following:
- Take a rest: you must take more breaks in order to rest your wrists and hands. This will help reduce the pressure that is already beginning to build up within the carpal tunnel.
- Avoid engaging in activities that will further worsen the condition or increase the pressure build-up.
- If swelling has already begun to occur, you can apply an ice pack to help reduce the swelling.
2. The moderate stage
This is the stage by which irritation has already occurred, and compression on the median nerve has already caused the syndrome.
In this case, one may need to apply a wrist splint and take medications in order to relieve the pressure and decrease the symptoms. At this stage, the numbness has already begun to occur; however, it is not as severe as the last stage.
3. The severe stage
At this stage, the person has begun to experience severe hand pain, increased numbness as well as atrophy of the muscles of the hand.
The patient will be required to go for a surgical procedure in which the pressure build-up can be relieved.
In the surgical procedure, the anterior transverse ligament, also known as the flexor retinaculum, is cut in order to relieve the pressure pressing on the median nerve. This surgical procedure may take two forms namely
- Endoscopic Surgery: This surgery involves the use of an endoscopic device to see the inside of the carpal tunnel. This kind of surgery is often less painful.
- Open surgery: This kind of surgery is more painful than endoscopic surgery, and it is often done when there is extreme pressure within the carpal tunnel.