What is spondylolysis?

Spondylolysis is an injury that occurs in the lower (Lumbar) vertebrae of the spine, usually in people who are predisposed to develop it. most of the time, this develops like a stress fracture, with early microscopic injury that can progress to the point that a visible fracture line exists. The posterior (back) portion of the vertebrae is the area involved, in a region called the “pars”. Arching the back into extension puts stress across this area and can lead to worsening of the problem if done often enough. Athletes involved in activities where the back is extended repetitively have a higher incidence of this problem. Some activities that carry a higher risk include:

• Gymnastics
• Weight lifting
• Diving
• Interior lineman in football
• Wrestling
• Volleyball
• Tennis

There are two Pars on any given vertebrae, to the left and right, and so spondylolysis can occur on one or both sides at any given level. It is most common in the lower lumbar areas. Most of the time, a spondylolysis does not cause symptoms, and often, there is probably union of the fracture fragments with scar-like tissue that makes the fracture stable. Athletic activity has the potential to disrupt these fibrous unions and bring out symptoms in a person who has previously been symptom-free.

If a spondylolysis is bilateral (on both sides), the portion of the vertebral column above the level of the fractures can actually start to slide forward relative to the portion of the spine that is underneath the fractures. This forward slip is termed “Spondylolisthesis”.

Spondylolysis is a problem that develops in young people and only progresses, if it is going to, until the early 20’s at the latest.

What are the symptoms of spondylolysis?

The important consideration for young athletes with back pain is that most young people do not have back pain, and that the relative incidence of back pain that is caused from things other than simply “muscle strain” is higher in young people than in adults. This means that any persistent complaint of low back pain in young people should be evaluated.

Those athletes who do have symptoms usually just complain of focused low back pain with activity, occasionally slightly to the side of the midline. If a spondylolisthesis is present, the nerves going into the legs from the back can be irritated and can cause symptoms that might be similar to patients with disc-related low back pain.

How is spondylolysis diagnosed?

Although certain findings on physical exam might point toward the possibility of spondylolysis, and physical exam in the hands of someone who is capable is usually good at excluding spondylolysis, ultimately, imaging studies will be required to diagnose this problem and to help make decisions about management once identified.

X-rays may show the fracture, and may show the forward slip of spondylolysis, and in that sense are diagnostic. if the x-rays are negative though, further imaging (such as with a CT scan or bone scan may be required to see if there is microscopic injury (a stress fracture). Alternatively, if the x-rays do show a fracture, further imaging is helpful to clarify whether or not there is much healing potential at the site of injury.

How is spondylolysis treated?

The management of spondylolysis varies based on the estimated healing potential of the injury. If the healing potential is felt to be low, the emphasis of treatment is on back strengthening for pain control (to minimize motion through the area of injury). Most of the time, pain from these injuries will slowly resolve and not cause chronic problems.

If healing potential is felt to be good, more aggressive treatment is warranted. Bracing to limit extension of the back will often be utilized, along with various periods of activity restriction to minimize ongoing injury.

Follow-up imaging studies, usually with CT scanning, will help to document if healing is occurring. When spondylolysis is bilateral, x-rays will insure that a spondylolisthesis is not occurring during the period of early and late adolescence when patients are most at-risk for this. Rarely, bone stimulators may be used in instances where healing is not occurring as expected.

Surgery for spondylolysis is rare, and is limited to either intractable pain in a non-healing lesion, or a large forward slip.