February 23, 2013
What is the difference between Carpal Tunnel Syndrome and Thoracic Outlet Syndrome?
Let's actually start at the other end of this. How are they similar? Why are they put in the same train of thought at all? Simply put: They share symptoms.
According to the National Institute of Neurological Disorders and Stroke, Carpel Tunnel Syndrome can trigger the following symptoms:
1. Sensation of burning, tingling, or itching numbness in the palm of the hand and the fingers, especially the thumb and the index and middle fingers
2. Fingers feel useless and swollen, even though little or no swelling is apparent
3. Symptoms often first appear in one or both hands during the night, since many people sleep with flexed wrists
4. One may wake up feeling the need to "shake out" the hand or wrist
5. As symptoms worsen, people might feel tingling during the day
6. Decreased grip strength may make it difficult to form a fist, grasp small objects, or perform other manual tasks
7. In chronic and/or untreated cases, the muscles at the base of the thumb may waste away
8. Some people are unable to tell between hot and cold by touch
Using NINDS as a source again, Thoracic Outlet Syndrome (TOS) can be broken down into three categories. Each of which have common symptoms of Carpel Tunnel Syndrome.
Neurogenic TOS has a characteristic sign, called the Gilliatt-Sumner hand, in which there is severe wasting in the fleshy base of the thumb. Other symptoms include paresthesias (pins and needles sensation or numbness) in the fingers and hand, change in hand color, hand coldness, or dull aching pain in the neck, shoulder, and armpit.
Venous TOS features pallor, a weak or absent pulse in the affected arm, which also may be cool to the touch and appear paler than the unaffected arm. Symptoms may include numbness, tingling, aching, swelling of the extremity and fingers, and weakness of the neck or arm.
Arterial TOS most prominently features change in color and cold sensitivity in the hands and fingers, swelling, heaviness, paresthesias and poor blood circulation in the arms, hands, and fingers.
It should be stated that the symptoms listed above for both CTS and TOS are not an exhaustive list, but a list of most common findings.
How are the different?
By anatomical definition, which also delves into cause.
Carpel Tunnel Syndrome, as defined by the The American Heritage Stedman's Medical Dictionary : Chronic pain and paresthesia in the hand in the area of distribution of the median nerve, caused by compression of the median nerve by fibers of the flexor retinaculum and associated with repetitive motion, as in typing or playing a musical instrument.
Thoracic Outlet Syndrome, as defined by the The American Heritage Stedman's Medical Dictionary: Compression of the brachial plexus and subclavian artery by attached muscles in the region of the first rib and the clavicle, characterized by pain in the arm, numbness in the fingers, and weakness in the hand muscles.
Both conditions deal with an affected median nerve. CTS is specific to having the median nerve pathology originate at the wrist, where the forearm flexors and the nerve pass under the retinaculum - the carpal tunnel. The median nerve provides sensory innervation to the skin of the palmar side of the thumb, index, middle fingers and the radial half of the ring finger. The radial side of the palm is innervated by the palmar cutaneous branch of the median nerve as well.
For TOS, the issue begins as a brachial plexus entrapment. The brachial plexus is the origin of the median nerve, but also houses the lower 4 cervical nerves (C5-C8) and the first thoracic nerve (T1). The nerve plexus is responsible for the motor innervation of all of the muscles of the upper extremity, with the exception of the trapezius and levator scapula. As the median nerve travels down the upper arm, although it is not innervating, it could still become entrapped by other muscles causing symptoms in the lower arm and hand.
Understanding the differences between these two conditions are important in treatment plans and self care. How can we get an idea of which condition is the source of our client's (or our own) symptoms. The following are special test suggestions and are in no way presented in lieu of professional medical opinions.
For Carpel Tunnel, The National Health Service Foundation presents:
PHALEN’S TEST: The essence of the test is that the wrist is flexed for one minute while the patient is asked to report whether their usual symptoms are precipitated. The forearm is held vertically and the wrist is allowed to drop into 90 degrees of flexion under the influence of gravity. If stiffness of the wrist does not permit 90 degrees of flexion then the wrist should be allowed to fall as far as possible.
REVERSE PHALEN’S TEST - The traditional Phalen’s test works because wrist flexion elevates the carpal tunnel pressure. Pressure measurements in the carpal tunnel confirm that this is the case, both in normal individuals and those with CTS but also that bending the wrist in the opposite direction (the movement known as extension) increases the carpal tunnel pressure too and to a rather similar extent.
TINEL’S SIGN - Some examiners use their own fingers to tap the wrist, others use a tendon hammer, and the exact site percussed may be over the carpal tunnel or may be proximal to it. Percussion over the wrist elicits tingling in the fingers this is widely believed to be a positive Tinel sign for CTS. It should be mentioned that in comparisons with other methods of making the diagnosis, Tinel’s sign may be very unreliable in CTS.
DURKAN’S CARPAL COMPRESSION TEST - this relies upon direct pressure applied externally by the examiner over the carpal tunnel to increase the pressure.
TOURNIQUET TEST- One of the earlier suggestions for temporarily increasing the carpal tunnel pressure was to apply a blood pressure cuff to either the upper arm or forearm, inflated to between systolic and diastolic pressure.
HAND ELEVATION TEST (Ahn 2001) - The hands are held above the head for two minutes and if this produces the same symptoms of which the patient is complaining then the test is positive.
For Thoracic Outlet Syndrome, the Mayo Clinic presents:
ADSON'S MANEUVER: For this test, you'll be asked to turn your head toward the symptomatic shoulder while you extend your arm, neck and shoulder slightly away from your body. While you inhale, your doctor will check for a pulse on the wrist of your extended arm. If your pulse is diminished or if your symptoms are reproduced during the maneuver, your doctor considers this a positive test result, which may indicate thoracic outlet syndrome. Because false-positives often occur, your doctor may repeat the test on the unaffected side.
WRIGHT TEST: From a sitting position and with the help of your doctor, you'll hold your arm up and back (hyperabduction), rotating it outward, while your doctor checks your pulse to see if it's diminished. As in the Adson's maneuver, your doctor will want to know if your symptoms are reproduced during the test.
ROOS STRESS TEST: From a sitting position, your doctor will ask you to hold both elbows at shoulder height while pushing your shoulders back. You will then repeatedly open and close your hands for several minutes. If your symptoms are present after the test, or if you feel heaviness and fatigue in your shoulders, this can indicate the presence of thoracic outlet syndrome.
Further medical testing might suggested by a medical professional before officially diagnosing Carpel Tunnel Syndrome or Thoracic Outlet Syndrome. Those test might include, but are not limited to: X-ray, Magnetic resonance imaging (MRI), Electromyography (EMG) and Nerve conduction study.