Carpal tunnel syndrome (CTS) is a common result of the inflammation caused by rheumatoid arthritis. CTS occurs when pressure is put on the median nerve, which runs from the forearm to the hand through a narrow space formed by bones and ligament at the center of the wrist called the carpal tunnel. The median nerve controls some of the muscles that work the thumb.
Tendons also run through the carpal tunnel alongside the median nerve. Rheumatoid arthritis prompts carpal tunnel syndrome when it causes swelling of the synovium, a membrane that surrounds those tendons.
"The tissues around the tendons get inflamed, and their near neighbor is the median nerve," says Nortin M. Hadler, MD, professor of medicine and microbiology/immunology at University of North Carolina at Chapel Hill and an attending rheumatologist at UNC Hospitals. The increased pressure on the median nerve causes the wrist pain and other symptoms related to carpal tunnel syndrome.
Carpal Tunnel Syndrome Symptoms
Callie Krakauskas, 31, a software engineer from Denver, has battled rheumatoid arthritis symptoms for 10 years. When she began having wrist pain about a year ago she just chalked it up to her arthritis.
"I would have little shooting pains in my wrists that went into my hands," she says. "I noticed I was losing strength. Things were slipping out of my hands more so than usual."
It's normal to mistake the signs of carpal tunnel syndrome for rheumatoid arthritis symptoms because they are very similar. "Rheumatoid arthritis has features that can mimic carpal tunnel syndrome, and carpal tunnel syndrome can be hidden under these features," Dr. Hadler says. Carpal tunnel syndrome symptoms include:
- Numbness, tingling, and pain in the thumb, index finger, and middle finger of the affected hand
- Progressive weakness and wasting away of the muscles around the base of the thumb, with subsequent loss of grip strength
- Shooting pains up into the forearm
- Loss of sensation in the affected thumb and fingers
For Krakauskas, the final clue came last fall when her hands began to go numb while she slept. "I would wake up with a pins and needles feeling in my hands," she says. She spoke to her doctor, who performed tests and diagnosed her problem as carpal tunnel syndrome.
Diagnosing and Treating Carpal Tunnel Syndrome
Diagnosis of carpal tunnel syndrome involves a series of tests that can include:
- A physical examination of the hands, arms, shoulders, and neck to rule out other possible causes for the symptoms
- Examination of the wrist and hands for swelling, warmth, pain, or discoloration, including testing fingers for sensation and examining the muscles at the base of the thumb for early signs of atrophy
- Specific physical tasks doctors have developed to reproduce the carpal tunnel syndrome symptoms
- Diagnostic procedures such as a nerve conduction study in which electrodes on the hand and wrist measure the function of the median nerve
Once carpal tunnel syndrome is diagnosed, doctors can proceed through a series of treatment options that include:
- Rheumatoid arthritis medications to reduce inflammation of the tissues causing CTS, other medications including NSAIDs (aspirin or ibuprofen, for example), and steroid injections
- Bracing or splinting the wrists to immobilize the tendons and give the inflamed tissue a chance to calm down
- Stretching the wrists regularly and taking frequent rest breaks
- Surgery on the top of the carpal tunnel to relieve pressure on the median nerve — an outpatient procedure done under local anesthesia that usually gives immediate relief
"For right now, I have braces I sleep in at night that engulf my wrists and hands, and I have smaller braces that I can use during the day at work," Krakauskas says. "It seems to be working pretty well. If I'm out of the braces, I can feel it sometimes and I have to put them back on. I'm trying to spend more and more time out of the braces, so I don't become reliant on them. My doctor said eventually I may need the surgery, but that's not for several years down the road."
Preventing Carpal Tunnel Syndrome
It may be possible to avoid carpal tunnel syndrome by:
- Taking medication to adequately control rheumatoid arthritis symptoms
- Stretching wrists and taking frequent rest breaks on the job
- Using ergonomically correct workstations and tools to ease pressure on the hands and wrists
- Avoiding repetitive tasks done for long periods of time that inflame the tendons of the wrist
However, keep in mind that studies have not shown that any of these approaches is a surefire way to prevent carpal tunnel syndrome. The best thing you can do is be aware of CTS symptoms and talk to your doctor as soon as you notice any of them.
Learn more in the Everyday Health Rheumatoid Arthritis Awareness Center.