Tarlov cysts: A cause of low back pain?

It's possible. However, Tarlov cysts are an uncommon cause of back pain.

Tarlov cysts are fluid-filled sacs that most often affect nerve roots at the lower end of the spine. Such cysts typically cause no symptoms and are found incidentally on magnetic resonance imaging (MRI) studies done for other reasons.

However, in some cases, the cysts expand, putting pressure on the affected nerve root. The results may include sharp, burning pain in the hip and down the back of the thigh, possibly with weakness and reduced sensation all along the affected leg and foot. Tarlov cysts sometimes enlarge enough to cause erosion of the surrounding bone, which is another way they may cause back pain.

In most cases, Tarlov cysts require no treatment. For those that do, some surgical treatments — such as draining the cyst — have had promising results. Because symptomatic Tarlov cysts are uncommon, studies have been too small and too dissimilar to identify the most effective treatment procedure.