Numb Hands Not Always Carpal Tunnel
Tuesday, February 21, 2012
By: Dale J. Buchberger, PT, DC, CSCS
Numbness and tingling in the hand may seem like a benign symptom but there can be many different causes of this symptom with different treatment strategies. The most common thought from patients is that numbness and tingling in the hand equals carpal tunnel syndrome. While carpal tunnel syndrome, or CTS, is common, there are other causes of numbness that need to be ruled out before putting on that wrist brace.
One of the nerves that supply the hand is called the median nerve. This is the nerve involved in carpal tunnel syndrome. This nerve travels across the wrist to supply sensation to the fingers. Repetitive bending and straightening of the wrist will injure this nerve. This tends to occur in people that use the computer frequently, use the cash register, or are involved in activities that require repetitive motion at the wrist.
Another nerve that supplies the hand is called the Ulnar nerve. This nerve passes behind the elbow at a point commonly referred to as the “funny bone”. Leaning on your elbow can put chronic pressure at this point compressing the ulnar nerve and causing numbness and tingling in the small finger of the hand. The radial nerve is the third nerve that supplies the hand. If you have numbness in the back of the web area between the thumb and index finger there may be a problem with the radial nerve either at the elbow or wrist.
Generally speaking, if the entire hand is numb or tingling then the problem is between the shoulder and the neck. If it involves both hands then a systemic cause such as diabetes should be considered. In the case of an anatomical cause between the shoulder and the neck, there are five areas in this short distance that can create numbness in the entire hand. This area is commonly referred to as the Thoracic outlet. Symptoms from this area are referred to as thoracic outlet syndrome, or TOS. If your shoulder is too loose or unstable this can also cause pressure on the nerves and blood vessels that pass by the shoulder, resulting in numbness and tingling in the entire hand. This is known as secondary TOS.
Since the nerves that supply the arms and hands originate in the spine, injury to the nerves at this level could cause numbness, tingling, and weakness in the hands. Generally patients often have shooting pain down the arm with this kind of a problem. The most common reason for nerve irritation in the neck is compression of the nerves as they exit the spine. There could be multiple causes for nerve compression, such as a herniated disc or arthritic development in the nerve tunnel. Injuries to the neck, such as a whiplash mechanism seen in a rear end automobile accident or even a collision sport such as football or ice hockey, can also result in numbness and tingling in the hands.
There are also other conditions that can cause numbness in the hands, such as an underactive thyroid (hypothyroid), kidney failure, infections such as shingles or herpes zoster virus, tumors and abnormal levels of calcium, potassium, or sodium in your body. This is by no means a complete list of the many causes of numbness and tingling in the hands, but it does give you the sense that there are many causes. Jumping to the “carpal tunnel conclusion” can be an error in judgment.
The good news is that the majority of these problems are treatable with a variety of treatments ranging from physical therapy to chiropractic treatment. If the cause turns out to be a herniated disc pushing on a nerve, this warrants a consultation with a neurosurgeon. When patients hear the word “surgeon” they can get nervous. Remember it never hurts to talk. Consulting with a surgeon doesn’t mean you are going to need or have surgery. Sometimes surgery affords you the best opportunity to resolve your condition. The majority of the time a good surgeon will offer you an opportunity to treat your condition non-operatively. You won’t know unless you speak to the right people.
In the case of the more peripheral nerve problems such as TOS or one of the nerve problems there are a number of soft tissue techniques such as Active Release Techniques (www.activerelease.com) or Sound Assisted Soft Tissue Mobilization (www.sastm.com) that are designed specifically for these types of nerve problems. If you have been diagnosed with a loose or unstable shoulder a program of physical therapy exercises for the rotator cuff can help to strengthen and stabilize the shoulder. If you have numbness and tingling in your one or both of your hands and it has been there for longer than 14 days you should have it examined by your doctor to establish the underlying cause.