Although carpal tunnel syndrome is the most common condition of the hand and upper extremity, not all cases of numbness and tingling in the hand are caused by carpal tunnel syndrome. There are over 30 other possible causes of hand numbness. However, alternative diagnoses, such as cubital tunnel syndrome (nerve compression at the elbow) and cervical radiculopathy (nerve compression in the neck), can occasionally be overlooked as the root cause of the problem and may need to be considered in some cases.
If you think you may be suffering from carpal tunnel syndrome, it is important to understand what carpal tunnel syndrome is. This condition is a result of a compressive neuropathy that causes numbness and tingling of the hand. A compressive neuropathy means that the nerve is trapped or compressed. This usually happens when the nerve passes through a tight passage or tunnel on its way to the hand. Similar to carpal tunnel syndrome, cubital tunnel syndrome and cervical radiculopathy are other compressive neuropathies that cause hand tingling and numbness. The differences in these conditions depend on the nerve or nerves that are involved and the location of nerve compression.
Carpal tunnel syndrome is caused by pressure on the median nerve where it passes through the carpal tunnel along with the flexor tendons as they travel from the forearm to the hand and fingers. The carpal tunnel is a bony canal formed by the carpal (wrist) bones. A strong ligament, called the transverse carpal ligament or flexor retinaculum, closes the palm side of the canal. This ligament serves as a pulley for the flexor tendons. The most common cause of the pressure causing carpal tunnel syndrome is “idiopathic,” meaning the cause is not proven or known. Many believe that the synovial lining around the tendons proliferates, or thickens, resulting in increased contents in the carpal tunnel and thereby pressing the median nerve against the transverse carpal ligament.
People who suffer from carpal tunnel syndrome often experience worse symptoms following sustained gripping activities, such as driving a car or holding a book or a newspaper. Another very common complaint is waking at night with numbness and tingling or pain in one or both hands. This is thought to potentially be the result of abnormal wrist posture during sleep, which places increased pressure on the nerve in the wrist. This theory is supported by the fact that wrist splints used to hold the wrist in a more open, physiologic position during sleep are one of the most effective nonoperative treatments.
The location of nerve pressure in cubital tunnel syndrome occurs in the elbow and involves the ulnar nerve. In the case of a cervical radiculopathy, nerve entrapment occurs in the neck. The specific nerve or nerves that are involved affect the location of hand numbness. For cases of carpal tunnel syndrome, the location of numbness is distributed along the course of the median nerve; thus, the thumb, index, middle, and a portion of the ring finger will be involved. In cases of cubital tunnel syndrome, the location of symptoms is distributed along the course of the ulnar nerve; thus, pain, numbness, and tingling will be located in the pinky and ring finger. Cervical radiculopathies may affect several nerves therefore causing the whole hand to be numb.
What Treatments are Available?
Nonsurgical treatments may include non-steroidal anti-inflammatories such as aspirin or ibuprofen, occupational therapy, chiropractic or other manipulative techniques, and cortisone injections. Patients that do not respond to these conservative treatments are usually treated surgically to relieve the pressure on the median nerve. Without surgery, permanent nerve damage may occur. Research has shown that nerve damage is a result of the length of time and amount of pressure on the nerve.
The most common surgery for carpal tunnel syndrome involves dividing the transverse carpal ligament to alleviate pressure on the median nerve. The ligament is cut to open the carpal tunnel about 5 mm; the larger passage relieves the pressure on the median nerve. In about six weeks, the ligament heals, allowing for return of normal strength. This older, more traditional, open surgical procedure requires a large incision through the skin, subcutaneous tissues, nerves, and muscles in order to allow the surgeon to see and cut the transverse carpal ligament. This results in longer healing times and more scar tissue than the newer, minimally invasive approach.
A newer surgical technique is endoscopic carpal tunnel release. Using an endoscope (tiny video camera smaller than a pencil), the surgeon is able to see and divide the transverse carpal ligament from inside the carpal tunnel through a very small incision called a “portal”. The surgery is performed without having to cut through tissue overlying the transverse carpal ligament. The incision is so small that no stitches are required following the procedure. Patients recover faster and experience less postoperative scarring, pain, and stiffness than patients that undergo the older, open surgical technique. Wide-awake anesthesia is an option for patients that do not want any sedation. Whereby the name implies, patients can be wide-wake during the surgery and can even watch the surgery on the monitor if they want. Wide awake methods have a lower risk of anesthesia and require no tourniqiuets (used for other types of surgery to stop the blood flow during surgery) are not typically used.
A study was conducted to compare the outcomes of endoscopic versus open carpal tunnel release on patients with carpal tunnel syndrome in both hands; they underwent an open procedure on one side and an endoscopic procedure on the other. The results of this study showed that patients universally preferred the endoscopic carpal tunnel procedure. Patient preference for the technique that uses was also later backed by a larger research study (a meta-analysis) showing similar results. This minimally invasive, no-stitches approach requires only tape (Steri-Strips) to close the wound. The incisions are so small that many patients are unable to see their scars. Most of patients return to work in a matter of days instead of months.
Dr. Tyson Cobb of Orthopaedic Specialists is performing this newer open surgery technique. One of Dr. Cobb’s patient’s who previously had an open surgery by another surgeon stated, “It was amazing the difference between the two surgeries and the recovery…I would recommend this surgery to anyone.” (Watch this patient’s success story at http://youtu.be/zGDIYXN4PLk). For more information on other procedures that Dr. Cobb performs or to learn more about Orthopaedic Specialists, visit our website at www.osquadcities.com. For a request for an evaluation, contact our office at 563-344-9292 or click here. Find us on Facebook and like us to stay up to date with treatment options and information: facebook.com/osquadcities.com.
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