Helping Hands Heal since 2005
From Dr. Z - Carpal tunnel syndrome specialist
There are two basic kinds of carpal tunnel tests: provocative and electrodiagnostic. The provocative tests are manual exams, which your doctor performs. But you can also perform them on yourself. The electrodiagnostic tests requires special equipment and must be performed in the doctor's office.
The provocative carpal tunnel tests are composed of the individual Tinel, Phalen, and Durkan tests. Holding the hand in a certain position or tapping the wrist will "provoke" symptoms if you have carpal tunnel syndrome.
The electrodiagnostic carpal tunnel tests are composed of the individual nerve conduction test and the electromyogram (EMG). They measure the electrical health of the nerve responsible for causing carpal tunnel syndrome.
This article describes each one of these test. It also explains what to you can expect from each test and what the results mean.
Your carpal tunnel tests are performed once you've established you have symptoms of this disorder. Those symptoms occur in your fingers and palm, but not your little finger. The illustration below indicates where these symptoms most likely occur. Signs of carpal tunnel syndrome in these areas are:
Signs of carpal tunnel syndrome first appear while the hand is resting. This is why patients are often awakened during a deep sleep to shake out the numbness in their fingers.
Another sign carpal tunnel is knocking at the door is when your hand feels awkward or clumsy while handling objects. People are aware of a change in their ability to open car doors, turn a door knob, or grasp a drinking glass.
Picking up small objects like keys or coins is also awkward. Tying s shoelace, buttoning a shirt or even using a comb seems clumsy.
As carpal tunnel syndrome becomes more advanced, symptoms intensify. They also appear during the day, when the hand is working. Pain can be unbearable. Numbness is often described as "crushing" or "punishing". Doctors call this stage severe carpal tunnel syndrome.
But that's not the end of the disorder. Carpal tunnel syndrome can get even more intense and severe. Patients lose the ability to perform fine motor tasks like writing with a pen. Many have severe loss of grip strength, and constantly drop things from their grasp. Then they lose the ability to sense hot and cold temperature in your fingertips.
Finally, end stage carpal tunnel syndrome is when the median nerve has died. Patients experience catastrophic loss of hand function. The thumb muscle wastes away.
Most patients also exhibit a phenomenon known as "claw hand". That's where the hand forms a claw shape when at rest due to the lack of median nerve input.
Within 6 months of symptoms appearing on the first hand, approximately 80% of patients will see symptoms appear on the other hand, too. Doctors refer to this "two-sided" disorder as bilateral carpal tunnel syndrome.
The primary risk factors for getting carpal tunnel syndrome are not well understood by medical science. However, we do know that certain conditions favor your getting this disorder. These are called "risk factors" and include:
Perhaps the most often-cited risk factor is performing stressful hand activities. When your hands are strained, the tendons react and cause the area to inflame and swell. As discussed below, this is the root cause of carpal tunnel syndrome.
So which activities cause such hand stresses? You can perform slow and forceful hand motions (like lifting weights). Or you can perform rapid and repetitive motions like typing or using a scissors.
This is why the following professions are known to have a high incidence of carpal tunnel syndrome:
Your doctor will perform carpal tunnel tests once he or she is satisfied that your symptoms match those of the disorder. Those symptoms are described above.
Why is it important to be sure of the diagnosis? It's because you don't want to be treated for carpal tunnel syndrome if you have another disorder!
There are several common "mimics" of carpal tunnel syndrome. Doctors can easily (and mistakenly) diagnose you with carpal tunnel syndrome when you actually have:
The nightmare scenario is being diagnosed with carpal tunnel syndrome but having one of these other disorders. And then you're wrongly referred to carpal tunnel surgery!
Sound impossible? Actually, studies show that carpal tunnel syndrome is frequently misdiagnosed. Some estimates are that misdiagnoses occur in over 70% of patients. That means over 70% of patients undergo carpal tunnel surgery unnecessarily!
So what's the actual cause of carpal tunnel syndrome? You might be surprised to find out that they're caused by damage to your median nerve. And that damage happens as a result of swollen flexor tendons.
The flexor tendons of the hand pull on your fingers to enable curling and gripping. They also allow you to play a piano, hold a scissors or lift heavy objects.
But those tendons can become strained very easily. You can strain them in dozens of ways. The most common examples are:
Any one of these actions can produce tremendous stress on your tendons. In fact, it's technically called repetitive stress injury or RSI.
As tendons undergo stress injury, they
inflame and swell.
As they do so, they push against the adjacent median nerve. This is a major nerve of the hand. When it's injured (or crushed by tendons) it reacts by giving you all of the
symptoms of carpal tunnel syndrome.
The provocative carpal tunnel tests are the Tinel, Phalen, and Durkan tests. Doctors perform these tests if they suspect you have carpal tunnel syndrome.
Note that you can also perform these provocative tests on yourself if you follow the instructions below. But it's always better if you have another person (a partner) perform the tests on you. The results will be more accurate.
A Tinel test starts by holding your hand straight out in front of you. With your opposite forefinger, tap the area of your wrist crease. Tap firmly, rapidly, and repeatedly. Move the tapping finger around about an inch, left and right. Keep tapping for 10-20 seconds.
A normal person will not feel anything but tapping. But if you feel pain, shooting electric shocks, numbness or tingling, then this is a positive sign you have carpal tunnel syndrome.
A Phalen test is best performed by holding your hand in an "L" position. You can push down on your own hand, press it against a hard surface, or have your partner bend it for you.
Be sure to push as hard as you can tolerate in order to make a sharp bend. Then hold the bend for 30-40 seconds.
A normal person will only feel stress in the wrist joint. But a positive sign for carpal tunnel syndrome is if you feel pain, tingling, or numbness in your fingers or palm.
A Durkan test begins by identifying the 2 large fleshy bumps in your lower palm, just above your wrist crease (as shown in the photo). Using your opposite thumb (or a partner's), press down between the bumps. Press hard, and hold the pressure for 30-40 seconds.
A normal person will only feel pressure at that point. But if you have carpal tunnel syndrome, a positive sign is when the pressing produces pain, numbness or tingling in the fingers or palm.
Electrodiagnostic carpal tunnel tests are usually conducted in 2 parts. These are the nerve conduction test and electromyographic test (also called EMG). Both of these tests must be performed by your carpal tunnel doctor because electronic equipment is needed.
It's important to mention that these electrodiagnostic tests are only used to confirm the above provocative carpal tunnel tests. The doctor should not use them alone to establish a diagnosis of carpal tunnel syndrome.
The reason is because both electrodiagnostic tests often give "false positive" results. In other words, they are not more accurate than the above provocative tests.
The nerve conduction test is used to determine if your median nerve is affected by crushing (by the tendons) in the wrist area. Electrical signals are applied at one end of the nerve, and their speed is recorded at the other end. If the nerve is crushed, then the electrical signal's velocity will be delayed.
This test begins when the medical technician tapes several electrodes to your palm area. The technician then uses an electrical stimulation device to initiate multiple pulses (bursts) of low-level electricity. These are the "signal pulses". The instrument can detect the speed of the pulses travelling along the median nerve.
These nerve conduction carpal tunnel tests are not painful. But patients say they feel tiny electric shocks on their skin, similar to static electricity.
Electromyographic (or EMG) carpal tunnel tests are similar to nerve conduction tests. They basically measure the health of your median nerve and your thumb muscles. The EMG can show if there is a delay in the electrical signals travelling between the nerve and muscle, possibly indicating carpal tunnel syndrome.
The test begins when the medical technician inserts one or two thin needles into your thumb muscles. These are the electrodes. Other surface electrodes are applied on the skin along the length of your arm.
Electrical pulses are sent between the surface and needle electrodes. The instrument they're connect to can determine the signal's speed and if there are any delays in the transmission. This can indicate if you have carpal tunnel syndrome.
There is no doubt that the EMG test is somewhat painful due to the needles required. When the signals are transmitted, patients say they feel burning or electrical shocks. The good news is that this test only lasts a few minutes.
The American Academy of Orthopedic Surgeons regulates and advises doctors about carpal tunnel surgery. They also specifically ask doctors to have their patients try ALL nonsurgical remedies first, before considering carpal tunnel surgery.
Using nonsurgical remedies first is important because they work in over 90% of patients. In contrast, carpal tunnel surgery is only about 50% successful (by the second year).
The primary nonsurgical remedies recommended are known as B.R.E.M. This stands for Brace, Rest, Exercise, Massage:
Bracing your wrist at night is simply a way of allowing it to rest while you sleep. In other words, a brace prevents you from unconsciously over-bending your wrist.
If you have carpal tunnel syndrome, such bending is harmful. That's because the bending exerts added pressure on your median nerve. And the median nerve is already under pressure due to inflamed tendons. But a brace will hold your hand in the "neutral position", meaning minimal pressure on the nerve.
But be careful! Not just any wrist brace will work. Actually, most "drug store" braces are harmful because they contain a "palmar spine". That spine will exert pressure on your wrist area as you bend your hand backward.
Instead, be sure to wear a certified carpal tunnel night brace. It's designed for carpal tunnel syndrome only. These braces maintain your hand in the neutral position without a palmar spine.
As a side note, you should never wear a wrist brace while you work. It forces your hand to work extra hard: against the brace while also doing its regular activity. This further stresses tendons.
The body heals with rest. And since stressed tendons are damaged and require healing, rest is a wonderful prescription to relieve carpal tunnel syndrome.
Doctors recommend taking short breaks when performing stressful hand activities. Even a minute will suffice for every hour you work.
You can also rest your hands by avoiding or curtailing the stressful hand or finger activity. That means, for example, avoiding prolonged typing sessions.
In time, your tendons will heal and inflammation will end. This in turn de-pressurizes the median nerve which then eliminates symptoms.
Exercises for your fingers and hand are supremely effective carpal tunnel fighters. In fact, regular exercises can relieve even difficult cases of carpal tunnel syndrome.
However, you must use exercises that maximize stretching of your flexor tendons. Doing so breaks up adhesions and restrictions along the tendon surface. This in turn allows the tendons to glide freely. As a result, inflammation is reduced - and so are carpal tunnel symptoms.
The proper carpal tunnel stretching routine should never take more than a minute to complete. Being fast and easy, you can therefore perform them every hour without having to sacrifice a large chunk of your work time.
Night bracing, rest, and stretching exercises work wonders when carpal tunnel symptoms are not too advanced. But if you have more severe symptoms you'll need more aggressive help in addition to these other remedies.
This is when wrist massage is needed. But not just any massage will suffice. Specifically, the type of manual manipulation required is called myofascial release massage.
When combined with night bracing, rest, and stretching exercises, the myofascial release massage will eliminate symptoms even in very severe instances of carpal tunnel syndrome.
Therapists use myofascial release massage because it's highly reliable in relieving symptoms. It works by destroying the adhesions on the surface of tendons. And it also drains excess fluid pressure from around the median nerve. These two mechanisms ultimately relieve pressure on the median nerve, and therefore, carpal tunnel symptoms.
Two basic types of carpal tunnel tests are used to determine if you have this painful condition. These are provocative tests and electrodiagnostic tests.
The provocative tests are composed of the Tinel, Phalen, and Durkan tests. These are "manual tests" where the doctor (or you) try to provoke symptoms by tapping, bending, or squeezing your hand. If symptoms occur during the tests, it means you likely have carpal tunnel syndrome.
The electrodiagnostic carpal tunnel tests are composed of the nerve conduction test and electromyography test (also called EMG test). These tests use surface and needle electrodes. A doctor must perform them. If they show abnormalities in the function of your median nerve, then it confirms that you likely have carpal tunnel syndrome.
There are several nonsurgical ways to treat carpal tunnel syndrome. These remedies should be used before surgery is ever discussed. That's because they effectively relieve symptoms in most patients.
