What is syringomyelia?

Syringomyelia (sear-IN-go-my-EEL-ya) is a disorder in which a cyst forms within the spinal cord. This cyst, called a syrinx, expands and elongates over time, destroying a portion of the spinal cord from its center and expanding outward. When a syrinx widens enough to affect nerve fibers that carry information from the brain to the extremities, this damage results in pain, weakness, and stiffness in the back, shoulders, arms, or legs. Other symptoms may include headaches and a loss of the ability to feel extremes of hot or cold, especially in the hands. Each patient experiences a different combination of symptoms depending on where in the spinal cord the syrinx forms and how far it expands.

Other, more common disorders share the early symptoms of syringomyelia. In the past, this has made diagnosis difficult. But the widespread availability of an outpatient imaging procedure called magnetic resonance imaging (MRI) has significantly increased the number of syringomyelia cases diagnosed in the beginning stages of the disorder.

Because syringomyelia can occur in association with other conditions, estimates of the number of Americans with the disorder vary widely, but a conservative estimate is that about 40,000 people in the United States are affected, with symptoms usually beginning in young adulthood. Signs of the disorder tend to develop slowly, although sudden onset may occur with coughing or straining. If not treated surgically, syringomyelia often leads to progressive weakness in the arms and legs, loss of hand sensation, loss of bladder and other functions, and chronic, severe pain.