Carpal Tunnel Syndrome
There has been a lot of recent hype about Carpal Tunnel Syndrome. This is because it is one of the syndromes that has been shown to be caused by chronic repetitive motions, such as typing or other computer work. However, in modern times it seems to have become a “garbage can diagnosis”: a catch phrase for any chronic wrist problem. The danger in this is it is often misdiagnosed, resulting in improper treatment and leading people to believe that their problem is worse than it really is. Lets examine the cause of Carpal Tunnel Syndrome more closely:
What is Carpal Tunnel Syndrome?
Wrap two of your fingers around your opposite wrist, right where your wrist is the smallest. Almost directly underneath your fingers lay the eight “carpal” bones. These bones connect with ligaments to create a groove on the palmar surface of the wrist, which allows some protection for the median nerve and the tendons that flex your fingers. The median nerve controls muscles of the thumb and the first 2 fingers of your hand. It also sends signals to your brain about temperature, pain and touch of these same fingers.
When this tunnel gets smaller (usually due to constant irritation of the tendons in the tunnel) it can irritate and restrict the nerve. This results in weakness and altered sensation in the thumb and first two fingers of the hand.
Though this scenario can occur, it is less common than most people may think, as any pinch on the median nerve will cause similar or identical symptoms.
Dispelling the Myths about Carpal Tunnel Syndrome
The following are three common myths that are often believed to be true:
Myth #1: All wrist pain is Carpal Tunnel Syndrome (CTS)
The Reality: True CTS is actually a lot more rare than people are led to believe, and is very specific in nature.
The wrist is especially designed for dexterous, sophisticated movement: There are approximately 23 joints in the wrist alone! The drawback to this enhanced degree of movement is that the wrist pays for it in stability: Other joints in the body depend on muscles as well as ligaments for strong support, however, there are no muscles that cross the wrist, so all the stability of these joints has to come from the tendons and the ligaments that hold all the wrist bones together. An injured ligament lacks the proper blood supply required for complete healing- meaning that once a wrist is injured, it very often results in permanent instability.
Considering that we use our wrists and hands constantly throughout the day, the potential for injury in the wrist tends to be quite high. Ask your family and friends. You will find that a significant number of them have chronic wrist pain, or have had a wrist injury at some point in the past. However, this does not mean that they have CTS.
There are many other “mimics” for CTS. Muscles in the forearm and the hand, or even the shoulder and neck can cause wrist and hand pain and numbness that is similar if not identical in nature to CTS. This is because the nerves that supply sensation and movement to the hand start as they branch off the spinal cord at the neck. These nerves can become pinched anywhere along their course, as they wind their way down to the hand. Often people will only feel the pain at the distant end of the nerve (called referred pain), especially if this is an area of previous injury and is now weakened. These problems respond quite well to treatment, and are easy to prevent- if the treating practitioner even looks at these areas.
Myth #2: I have CTS and it is not getting better. I must need Surgery.
Reality: Pain that appears to be CTS may not be getting better simply because the practitioner has not found the true source of the pinch on the nerve. Surgery may be unnecessary and detrimental.
Conservative treatment focuses on loosening the sheath of the carpal tunnel and relaxing the muscles that may be contributing to the tunnel’s constriction, thereby taking the pinch off the nerve. Cases that are resistant to treatment are commonly scheduled for surgery to release the pressure of the tunnel by splitting the sheath open. This surgery can be successful for properly diagnosed cases, however if the pinch on the nerve is coming from an area other than the wrist, not only will the surgical attempt fail, but the problem can get worse, because a buildup of scar tissue at the surgical site can actually begin to create a pinch of the median nerve at the carpal tunnel as well!
Once again, proper diagnosis is imperative. A thorough exam for symptoms of CTS will include a neck, shoulder, ribcage, elbow, wrist and hand evaluation. Nerve conduction tests can minimize the chances of unnecessary surgery, so they are an important diagnostic procedure for a stubborn case of wrist pain.
Myth #3: Because I have CTS I will have disabling wrist pain for the rest of my life.
Reality: Lifestyle modifications may be necessary, but the majority of cases of wrist pain are quite treatable, even if it is CTS.
The wrist is a complicated joint, and injuries to the wrist don’t tend to heal as well as injuries to the arm or forearm, therefore those problems tend to persist. However, with a correct diagnosis and occasional maintenance treatment, the majority of wrist pain can be minimized or even prevented.
The bottom line
Don’t diagnose yourself: If you think you have CTS get it treated. A good practitioner will check along the whole chain of the nerve to determine if the pinch is truly coming from the wrist. Try every alternative therapy before submitting to the knife! Remember, this wrist is complicated: maintenance treatment may be necessary if you are in a job which requires repetitive forearm or wrist motion.
References:
D’Arcy and McGee: Does this patient Have Carpal Tunnel Syndrome?
JAMA Vol 283 No. 23(June 21, 2000) 3110-3117
Netter, F: Atlas of Human Anatomy. Novartis. 1989. pp.428-429
Souza TA: Differential Diagnosis for the Chiropractor. Aspen Publishers, 1998.
pp. 191-219.