What is spondylolisthesis?

The spine is made up of a series of connected bones called “vertebrae.” In about 5% of the adult population, there is a developmental crack in one of the vertebrae, usually at the point at which the lower (lumbar) part of the spine joins the tailbone (sacrum). It may develop as a stress fracture. Because of the constant forces the low back experiences, this fracture does not usually heal as normal bone. This type of fracture (called a spondylolysis) is simply a crack in part of the vertebra and may cause no problem at all. However, sometimes the cracked vertebra does slip forward over the vertebra below it. This is known as adult isthmic spondylolisthesis..

What are the symptoms?

Isthmic spondylolisthesis may not cause any symptoms for years (if ever) after the slippage has occurred. If you do have symptoms, they may include low back and buttocks pain; numbness, tingling, pain, muscle tightness or weakness in the leg (sciatica); increased sway back; or a limp. These symptoms are usually aggravated by standing, walking and other activities, while rest will provide temporary relief.

Studies have shown that 5-10% of patients seeing a spine specialist for low back pain will have either a spondylolysis or isthmic spondylolisthesis. However, because isthmic spondylolisthesis is not always painful, the presence of a crack (spondylolysis) and slip (spondylolisthesis) on the X-ray image does not mean that this is the source of your symptoms.

How is it diagnosed?

Your doctor will begin by taking a history and performing a physical examination, and may order X-ray studies of your back. However, sometimes it is difficult to see a crack and/or slippage on an X-ray image, so additional tests may be needed. A computed tomography (CT) scan can show a crack or defect in the bone more clearly. A magnetic resonance imaging (MRI) scan may be ordered to clearly show the soft tissue structures of the spine (including the nerves and discs between the vertebrae) and their relationship to the cracked vertebra and any slippage. It also will show whether any of the nearby discs have suffered any wear and tear because of the spondylolisthesis (slippage).

If isthmic spondylolisthesis is present, it can be graded as I, II, III or IV based on how far forward the vertebra has slipped.

How is it treated?

If your doctor determines that a spondylolisthesis is causing your pain, he or she will usually try nonsurgical treatments first. These treatments may include a short period of rest, anti-inflammatory medications (orally or by injection) to reduce the swelling, analgesic drugs to control the pain, bracing for stabilization, and physical therapy and exercise to improve your strength and flexibility so you can return to a more normal lifestyle. If you are told to rest, follow your doctor’s directions on how long to stay in bed. Generally, if recommended at all, this would be limited to a few days. (Strict bed rest is usually not necessary.) Ask your doctor whether you should continue to work while you are being treated.

Your doctor may also — sometimes with the help of a nurse or physical therapist — begin education and training in performing activities of daily living without placing added stress on your lower back.

If a combination of medication and therapy fails to provide relief, however, your doctor may order additional tests, which will provide greater detail so he/she can plan further treatment.


Also see...