A Patient’s Guide to Spondylolysis/Spondylolisthesis


Image showing a weak point in the spine affected by a Spondylolysis

Spondylolysis and spondylolisthesis are not your everyday terms thrown around by people who suffer from back pain. However, for some people, these words do have meaning. These two conditions affect about five to six percent of the population, and can lead to chronic back pain.

The purpose of this information is to help you understand:

  • The causes of spondylolysis and spondylolisthesis
  • How a diagnosis is made
  • The treatment for spondylolysis and spondylolisthesis


In order to understand your symptoms and treatment choices, you should start with some understanding of the general anatomy of your spine. This includes becoming familiar with the various parts that make up the spine and how they work together.

Please review the document, entitled:

Spondylolysis refers to a defect in one of the vertebra in the lower back, usually the last vertebra of the lumbar spine. The area of the vertebra called the pedicle is affected. The pedicle is part of the bony ring that protects the spinal nerves, and is the portion that connects the vertebral body to the facet joints. When a spondylolysis is present, the back part of the vertebra and the facet joints simply are not connected to the body – except by soft tissue. It is almost as if the back portion had been broken off and tried to heal – but never did. Actually, there is good evidence to suspect that this is exactly what has occurred. Spondylolysis is not something people are born with, but it appears to first show up sometime in childhood. Interestingly, boys who are football linemen and girls who are gymnasts seem to be affected the most. The current thought is that the spondylolysis is probably a stress fracture that never completely healed.

Spondylolisthesis is the term used to describe when one vertebra slips forward on the one below it. This usually occurs because there is a spondylolysis in the vertebra on top. There are two main parts of the spine that keep the vertebrae aligned – the disc and the facet joints. When a spondylolysis occurs, the facet joint can no longer hold the vertebra back. The intervertebral disc may slowly stretch under the increased stress and allow the upper vertebra to slide forward. In the vast majority of cases, the stretching only allows a small amount of forward slip. Furthermore, there is no real danger in an adult that the slipping will continue until the upper vertebra slips off.

There is a special type of spondylolisthesis in teenagers where the forward slipping is extremely severe. This can lead to the upper vertebra slipping completely off the lower vertebra.


Spondylolysis and spondylolisthesis are important because they can be a cause of low back pain. Just because you have one of these conditions does not mean that you will necessarily ever have problems with your back. However, you are at a higher risk than the normal population of developing chronic low back pain. These conditions can cause typical mechanical and/or compressive (or neurogenic) type back pain symptoms.

If you have not reviewed A Patients Guide to Back Pain you may want to now.

A Spondylolysis causing an irritated nerve root

The mechanical symptoms occur primarily because the spinal segment affected by the spondylolysis is unstable resulting in segmental instability. The compressive symptoms can arise because the nerves at the segment involved are pinched. There is usually a lump of tissue in the area of the spondylolysis – probably where the fracture tried to heal itself. This lump of tissue may press on the nerve roots as they leave the spine. The forward slip of the vertebra also makes the spinal canal smaller, leaving less room for the nerve roots.

There is usually pain across the small of the back and into the buttocks. If there are compressive symptoms, there may be pain down the leg to the foot, numbness in the foot, and possibly weakness in trying to raise the foot.


The diagnosis of spondylolysis and spondylolisthesis is dependent on seeing the abnormality on either: X-rays, a CAT scan, or an MRI scan. In most cases, it is easily seen on regular X-rays of the low back. The symptoms are no different from other causes of low back pain. On the other hand, just because you have a spondylolysis or spondylolisthesis on your X-ray does not mean your symptoms are from the defect. You may still have a herniated disc or some other condition that is causing your pain. Your doctor will need to carefully look for any possible causes of pain.


In order to make a proper diagnosis and rule out other possible conditions, the first step is to take a history. The provider may ask about the following:

  • Date of Onset – When did you first notice the appearance of your spinal condition?
  • The Presence or Absence of Pain – Not all cases of spondylolysis produce pain. However, if there is pain, the doctor will need to know where it is, what brings on or intensifies the pain, and if there is any radicular pain. Radicular refers to pain that radiates away from the spine to other parts of the body. This usually comes from irritation of the nerves as they leave the spine.
  • Bowel or Bladder Dysfunction – Are you having problems knowing when you have to urinate or have a bowel movement? This is extremely important because it could signal the presence of serious nerve damage.
  • Motor Function – Has there been a change in how your muscles work? This may be the result of pressure on the nerves or spinal cord itself.
  • Previous – If you have had any surgery on your spine, it may have caused some type of degenerative spondylolisthesis. In order to evaluate your condition properly, it is important that your physician knows about any spinal surgery you have had in the past.

Physical Exam

The spine specialist will then perform a physical examination. During the exam, the provider will try get an understanding of your back problem and how it is affecting you. Finally, your nerves will be tested by: checking your sensation, your reflexes, and the strength of your muscles.

Additional Tests

Usually, after the examination, X-rays will be ordered that allow the provider to see the structure of the spine and measure the slippage from the spondylolisthesis. During the X-rays, you will be asked to hold certain positions while standing or lying on a table, and you will need to hold very still while pictures are taken of your spine.

Depending on the outcome of your history, physical examination, and initial X-rays, other tests may be ordered to look at specific aspects of the spine. The most common tests that are ordered are: the MRI scan – to look at the nerves and spinal cord; the CAT scan – to get a better picture of the vertebral bones; and special nerve tests – to determine if any nerves are being irritated or pinched.

To learn more about these tests, you may wish to review the document, entitled:


Treatment for spondylolysis and spondylolisthesis is not much different than for other causes of mechanical and/or compressive back pain. In most cases, surgery will not be necessary. Strengthening the back muscles can reduce the mechanical symptoms resulting from the segmental instability.

A physical therapist will probably be recommended to help you with a series of exercises designed to help stabilize the spine by strengthening the back and abdominal muscles.

Medications may be used for short periods to: control pain, ease muscle spasms, and help regain a normal sleep pattern (if you are having trouble sleeping). Short periods of bed rest may help with acute painful episodes.

A back brace, or corset, may reduce pain. For more information on the braces used in the treatment of spondylolisthesis, you may wish to review the document, entitled:


Surgery is necessary only if all of the above treatments fail to keep your pain at a tolerable level. Surgical treatment for spondylolysis and spondylolisthesis must address both the mechanical symptoms and the compressive symptoms if they are present. Usually this means that the nerves exiting the spine must be freed of all pressure and irritation. Performing a complete laminectomy (removing the lamina) usually does this. Removing the lamina allows more room for the nerves. It also enables the surgeon to remove the lump of tissue surrounding the spondylolysis defect. The result is reduced irritation and inflammation on the nerves. Once the nerves are freed, a spinal fusion is usually performed to control the segmental instability.

For more information on the surgical treatment of spondylolisthesis, you may wish to review the document, entitled: