Yet the condition called cervical myelopathy can progress with few symptoms.
If you have rheumatoid arthritis, you’re well-acquainted with its ability to wreak extensive joint damage and destruction. This erosive process is typically all but impossible to ignore, causing the joints to become painful, swollen, tender and warm to the touch. If left untreated or if there is poor response to treatment, the erosion can lead to disabling and even crippling joint deformation.
RA damages the joints by producing inflammation of the synovium, the membrane that lines the joints. Chronic inflammation of the synovium causes fluid to accumulate in the joints, irritating the bones and causing the supporting ligaments to stretch and lose their elasticity and strength.
In the neck, the ligaments supporting the cervical discs become lax and can even tear, causing the discs to become unstable and misaligned. This can ultimately lead to cervical myelopathy, which is defined as compression – or squeezing – of the spinal cord.
The joint of the first and second cervical vertebrae – C1 and C2 – is most commonly affected. This joint is unusual because it allows more movement than any other joint in the spine.
“As a result, the first cervical vertebra, called the atlas, can shift onto the second vertebra, or axis,” says Dr. Christopher Morris, a rheumatologist in private practice in Tennessee. “This causes narrowing of the canal where the spinal cord goes through.”
The joint destruction seen in RA is usually clear – you can feel and see the damage. But in the case of cervical myelopathy, the joint erosion often progresses with few – if any – noticeable symptoms.
“[Cervical myelopathy] can often be asymptomatic, [although] some people will notice numbness and tingling in their arms and legs,” Morris says. In some cases, it can also affect bowel or bladder function, causing a lack of control.
When cervical myelopathy compresses or irritates the nerves where they branch away from the spinal cord, it can cause cervical radiculopathy, or a pinched nerve, causing pain that radiates into the shoulder and muscle weakness and numbness that can extend into the arm and hand.
According to Morris, between 5 percent and more than 80 percent of people with RA are estimated to have changes to the cervical spine.
Dr. Kushagra Verma, a spine surgeon at the University of Washington Medical Center in Seattle, puts the number even higher.
“Patients with RA have a 90 percent risk of cervical spondylosis, or advanced degenerative changes in the spine,” Verma says. “In both RA and non-RA spines, cervical myelopathy develops as the spine ages. In RA, these changes occur more rapidly than in non-RA patients,” says Verma, who is an assistant clinical professor of spine surgery at the University of Washington School of Medicine. “The disc degenerates over time, causing a loss of disc height. This leads to a loss of the normal cervical spine curvature, called kyphosis.”
According to Morris, although the incidence of cervical myelopathy in people with RA does increase with age, it is more common in people who have had RA for several years, particularly in individuals with known joint damage and deformity. “Age does not play a role [in the development of cervical myelopathy] as much as duration of the disease, and the severity of deformity and ‘mutilation’ caused by the disease.” The use of corticosteroids also seems to increase the risk, he says.
“Most patients with mild compression have no symptoms,” Verma says.
“Most patients with mild compression have no symptoms,” Verma says.
And, Morris says, in some cases, symptoms may not be identified correctly. “It can take months for someone to be diagnosed [correctly], usually because symptoms are attributed to other reasons,” he says.
The larger the shifting and separation of the discs, called subluxation, the more likely there will be nerve damage.
“Patients with neurologic symptoms suggest urgent intervention is needed,” Morris says. “Stabilization of the neck is certainly required. The concern is that a mild trauma, such as being ‘rear-ended,’ could result in permanent damage to the spinal cord, paralysis and even death,” he explains. “The goal is usually to proceed to surgery when mild nerve symptoms are found, since delay might lead to more severe damage and a poorer outcome.”
Neurological symptoms can include difficulty with fine motor skills and problems with balance or walking in a straight line. “One of the first notable changes is a change in handwriting,” Verma says. “The goal of surgery is to prevent the progression of symptoms, but often surgery can help many of the symptoms.”
It’s also possible to have significant compression of the spinal cord in the cervical spine without significant symptoms, Verma says. “If the compression is mild without bruising of the spinal cord, then the patient can be observed closely,” he says. “If there is bruising of the spinal cord on MRI, it suggests early injury. Most surgeons would recommend surgery even if a patient has no symptoms,” he adds.
In general, patients with RA have a high rate of complications compared with patients in the general population, Verma says. “This has to do with the increased wound infection risk and poor bone quality associated with RA,” he explains. But despite the elevated risks, “patients with RA and cervical myelopathy have good outcomes, especially when the myelopathy is not too severe,” he says.
Some people may not be good candidates for surgery, including individuals with multiple medical problems, the elderly or those with very poor bone quality, Verma says.
“Some people may not be good candidates for surgery, including individuals with multiple medical problems, the elderly or those with very poor bone quality.”
There are no good nonsurgical treatment options for cervical myelopathy. “If balance issues are mild, they can sometimes be treated with physical therapy,” Verma says. “Patients may benefit from seeing a neurologist as well, especially if the cause of the balance problems is not clear.”
There are three main surgical treatment options for cervical myelopathy. The first is anterior cervical discectomy/disc replacement and fusion, in which the damaged disc is removed and either replaced with an artificial disc to preserve motion or fused. The second option is posterior decompression/fusion, in which the bony arch, or lamina, is removed from the back of the spine to open up space for the spinal cord. The third technique is cervical laminoplasty, a newer, nonfusion surgery.
“The space for the spinal cord is opened up with a bone graft or small plates without fusion of the cervical vertebrae,” says Verma. “This procedure is best done to preserve range of motion in a person with myelopathy but no significant neck pain,” he adds.
New Mexico Orthopaedics is a multi-disciplinary orthopedic clinic located in Albuquerque New Mexico. We have multiple physical therapy clinics located throughout the Albuquerque metro area.
New Mexico Orthopaedics offers a full spectrum of services related to orthopedic care and our expertise ranges from acute conditions — such as sports injuries and fractures — to prolonged, chronic care diagnoses, including total joint replacement and spinal disorders.
Because our team of highly-trained physicians specialize in various aspects of the musculoskeletal system, our practice has the capacity to treat any orthopedic condition, and offer related support services, such as physical therapy, WorkLink and much more.
If you need orthopedic care in Albuquerque New Mexico contact New Mexico Orthopaedics at 505-724-4300.