Lumbar Spine Cysts

Is Surgery the Only Option?

Question: My husband has a cyst on his lumbar spine. Can the cyst become infected or burst? And is surgery the only option?
—Kenosha, WI

Answer: There are actually 6 kinds of cysts that occur near the lumbar spine. The causes and treatments for each are very different.

Digital illustration of cyst in colour background The first kind is called a synovial cyst. This is an outpouching of the lining of the facet joint. The joint is normally lined with lubricating fluid called synovium. That lining can extrude out of the joint from trauma or degeneration and form a cyst.

This cyst can be painful and can also pinch nerves. They may rupture, but usually it is the cyst wall that is problematic. The wall is often very thick and adheres to the surrounding nerve tissue. Consequently, needle aspiration, or drainage, of these cysts is seldom effective and surgery is usually required.

Ganglion cysts function much like synovial cysts but arise from the posterior longitudinal ligament (which is located behind the spine and inside the spinal canal). They often require surgical removal if they become symptomatic.

The third kind of cyst is a Tarlov cyst, which is a cyst of the nerve roots commonly in the sacrum (or lower spine). These are more common in women and are frequently found incidentally on MRI imaging for low back pain.

Tarlov cysts rarely cause any problems, but when they do, they can affect the neighboring nerves. This may result in pain, weakness, numbness, or bowel/bladder problems. While drainage of the cyst is easy, the fluid typically recurs. So if treatment is truly indicated, most surgeons recommend removal of the cyst and closure with glue.

Arachnoid cysts are the fourth type of lumbar spine cyst and, like Tarlov cysts, they are usually asymptomatic (that is, they typically don't have any symptoms). They are often present at birth and make a pocket of fluid in the cerebrospinal fluid space that may be found on MRI but have no clinical consequence (they won't cause medical problems down the line). Since they cause no symptoms, they do not need to be treated.

Intradiscal cysts are the fifth kind of cyst, but they are very rare. They are similar to disc herniations in that they arise from the disc and can cause radiculopathies (pain that travels away from its source). These cysts typically respond to non-operative treatments.

Finally, sebaceous cysts are the sixth kind of cyst that may be found in the low back. These are cysts in the skin that can occur anywhere in the body. Typically they arise from swollen hair follicles, and these cysts may produce protein or oil.

Because sebaceous cysts can build up pressure and are close to the skin where normal bacteria are found, they can rupture and become infected. These are the only cysts with a propensity for infection. Like the other lumbar spine cysts, they may need surgery if other treatments fail.