Carpal tunnel syndrome is a common condition of the wrist and hand and can often be treated non-surgically. Carpal tunnel syndrome occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes pressed or squeezed at the wrist.
Anatomy of the Carpal Tunnel
In order to understand carpal tunnel syndrome, it’s important to understand the anatomy of the hand—namely the carpal tunnel. The carpal tunnel is a narrow passageway or channel located on the palm side of the wrist. It is comprised of eight bones—called carpals—that form an arch creating three rigid walls of the channel. A band of tissue—called the transverse carpal ligament—covers this arch, forming a “roof” over the channel. This tunnel protects the median nerve, which is the main nerve to the hand and the nine tendons that bend the fingers and thumb.
The median nerve is important because it controls sensations to the palm side of the thumb and first three fingers (not the little finger) and impulses to some of the small muscles in the hand that enable movement in the fingers and thumb.
Carpal Tunnel Syndrome
Carpal tunnel syndrome is a condition of the hand and wrist that occurs as a result of pressure on the median nerve in the wrist. Compression of the median nerve can lead to numbness, tingling, weakness, and pain in the hand and wrist. This numbness sometimes radiates up the arm.
Symptoms of Carpal Tunnel Syndrome
Carpal tunnel syndrome may begin with a gradual onset of numbness and tingling in the thumb, index, and middle fingers (but not the little finger). The numbness may come and go. Some people experience pain in the arm between the hand and the elbow.
Typically, carpal tunnel syndrome is characterized by:
- Numbness: The first symptom of carpal tunnel syndrome is usually numbness or tingling in the thumb, index finger, middle finger, and half of the ring finger. The sensation may occur during everyday activities, such as gripping a steering wheel, holding a book, combing hair, holding the phone, or when waking from sleeping. Initially, the numbness may come and go. Over time, it may become more constant. Many people “shake out” their hands to try to relieve the symptoms.
- Weakness: Carpal tunnel syndrome can result in weakness and muscle loss. As pressure on the median nerve increases, some people experience a weakened grip. As a result, people with carpal tunnel syndrome may have a tendency to drop objects.
- Pain: Pain is a less common symptom of carpal tunnel syndrome. Sometimes constant numbness can lead to pain. Some people experience an ache in the thumb, wrist, hand, or even pain that spreads up to the shoulder and neck.
Causes of Carpal Tunnel Syndrome
Put simply, carpal tunnel syndrome is caused by compression of the median nerve—but what causes that compression? There is no simple answer to that question. The compression could be the result of one or a combination of many factors. Anything that causes swelling or makes the carpal tunnel smaller can cause pressure on the median nerve.
Factors that can lead to carpal tunnel syndrome include:
- Congenital Predisposition: Some people are born with a carpal tunnel that is smaller than average, which leaves little room for the nerve and tendons. This places them at higher risk of developing carpal tunnel syndrome.
- Trauma: An injury to the wrist—such as a sprain or fracture—can cause swelling that leads to pressure on the nerve.
- Disease: Diseases such as hypothyroidism, rheumatoid arthritis, and diabetes can cause inflammation or fluid build-up, which can put pressure on the median nerve.
- Repetitive Motion: Activities that involve repetitive motion can lead to compression of the median nerve. For example, assembly line workers, hairstylists, cashiers, or people who use a computer all day may be at risk for developing carpal tunnel syndrome.
- Hormonal Changes: Hormonal changes during pregnancy or menopause may cause fluid retention, which can place pressure on the median nerve.
- Growths: Infections, cysts, or tumors in the carpal tunnel will take up extra space and compress the median nerve.
The median nerve can only withstand a small amount of pressure for a short time. Anything that crowds, irritates or compresses the median nerve over time can lead to carpal tunnel syndrome.
Diagnosis of Carpal Tunnel Syndrome
Early diagnosis of carpal tunnel syndrome is important to avoid permanent damage to the median nerve and to prevent the condition from worsening.
Diagnosis may involve some or all of the following:
- History: The history of symptoms often serves as a good indicator of carpal tunnel syndrome. In addition, work and activity patterns may provide insight.
- Physical Examination: A doctor will examine the wrist and the thumb and first three fingers for tenderness and swelling. Each finger will be tested for sensation and the muscles at the base of the hand will be examined for strength and signs of atrophy. Doctors can perform manual tests to produce the symptoms of carpal tunnel syndrome:
Phalen’s Maneuver: This is a wrist-flexion test that requires a patient to hold the forearms upright with the wrist bent and the fingers pointing down and pressing the backs of the hands together. If the added pressure on the nerve creates tingling or numbness, carpal tunnel syndrome may be present.
Tinel’s Sign: During this test, the doctor gently taps on or presses on the median nerve in the wrist. If the patient experiences tingling in the fingers or shock-like sensations, carpal tunnel syndrome may be present.
- Electrodiagnostic Tests: Some doctors will confirm a diagnosis of carpal tunnel syndrome with electrodiagnostic tests:
- Nerve Conduction Study: This study is performed by placing electrodes in the hand and wrist and then applying mild electrical current to the nerve in order to determine the speed with which the nerve is transmitting impulses and thereby determining how well the nerve is working.
- Electromyography: Electromyography measures the electrical activity of muscles. During electromyography, a tiny needle is inserted into a muscle and the electrical activity is viewed on a screen. This can help determine the extent of damage to the median nerve.
- Imaging Tests: Ultrasound imaging can reveal impaired movement of the median nerve; however, magnetic resonance imaging (MRI) has not been shown to be helpful in diagnosing carpal tunnel syndrome.
Treatment of Carpal Tunnel Syndrome
Treatment of carpal tunnel syndrome should begin as soon as possible in order to prevent worsening of symptoms. When diagnosed early, carpal tunnel syndrome can often be treated non-surgically. In fact, most doctors will begin with a non-operative approach and will only proceed to surgery if symptoms persist.
Of course, it’s important to treat underlying causes, such as diabetes or hypothyroidism, first.
Non-Surgical Treatment for Carpal Tunnel Syndrome
There are a variety of non-surgical approaches for treating carpal tunnel syndrome:
- Rest: Rest the affected hand/wrist and avoid activities that aggravate symptoms. Repetitive movements may make symptoms worse. If possible, patients should avoid such activities. Continued computer use can be one of the worst villains for carpal tunnel syndrome. At the very least, it’s important to take frequent breaks from the computer (at least five minutes every half hour).
- Immobilization: A wrist splint can be used to hold the wrist in a straight position and prevent further damage. The splint is most important during sleep because many people curl up with bent wrists during sleep, which places added pressure on the median nerve. Many patients wear the splint throughout the day as well.
- Oral Medication: NSAIDs (non-steroidal anti-inflammatory medications), such as aspirin and ibuprofen may help reduce pain and swelling, which can relieve the pressure on the median nerve.
- Steroid Injections: A corticosteroid injection—more commonly known as a cortisone shot—is a powerful anti-inflammatory agent injected directly into the carpal tunnel. The shot can reduce inflammation and pain. Steroid injections for carpal tunnel syndrome are successful in about 20-50 percent of patients, but symptoms often return.
- Physical Therapy: Once symptoms have subsided, stretching and strengthening exercises can be helpful. It’s important to work with a hand therapist who is specially trained in treating this condition.
Surgical Treatment for Carpal Tunnel Syndrome
Surgical treatment may be necessary if symptoms do not respond to non-surgical treatment after six months or if symptoms are severe and there is significant damage to the median nerve. Surgery is more often necessary in patients who have had symptoms for several years before seeking treatment—which is why it is so important to seek treatment early.
Surgery for carpal tunnel syndrome is called carpal tunnel release and is one of the most common surgical procedures in the United States. There are two ways to perform the procedure:
- Open Release Surgery: During an open procedure, the surgeon will make a small incision at the base of the palm and cut the transverse carpal ligament to open the roof of the carpal tunnel. This relieves pressure on the median nerve.
- Endoscopic Release: During a minimally invasive endoscopic procedure, a surgeon makes two tiny incisions in the wrist and palm and inserts a small tube that contains a fiberoptic camera. This allows the surgeon to see the underside of the transverse carpal ligament and to cut it with a special knife and relieve the pressure on the median nerve.
Regardless of which procedure is performed, it is typically a short, 30-minute procedure performed in an outpatient setting. Both techniques have high success rates and 90 percent of patients experience relief of symptoms.
Recovery from Carpal Tunnel Syndrome Surgery
Recovery from carpal tunnel syndrome takes time and may require permanent lifestyle changes. With non-surgical treatment, relief of symptoms can take days, weeks, or months. Patients may need to decrease their use of repetitive motions and build more rest into their day. Patients who undergo surgical treatment may notice relief of symptoms within days—but it can take months to fully recover.
Whether a patient undergoes non-surgical or surgical treatment for carpal tunnel syndrome, a hand therapist can be fundamental to recovery. Qualified hand therapists at OSMI Fort Worth can prescribe exercises to improve circulation, motion, and strength. What’s more, hand therapists can help patients learn proper ergonomics to help prevent continued symptoms.
If you have Carpal Tunnel Syndrome, or even mild wrist or hand discomfort that you would like to relieve, choose our team of hand, wrist and elbow orthopedic and sports medicine specialists that offer state-of-the-art treatment and highly personalized care, contact the OSMI office or call 817-529-1900 today!