Spondylolisis is the most common cause of back pain in children and adolescents. The condition is caused by fatigue fracture in the bony elements of one of the spinal segments. The technical name for the area of weakness or fatigue fracture is called the “Pars Interarticularis”. The level most commonly affected is L5 and is thought to occur due to repetitive backward bending (hyperextension) stress. There maybe a hereditary factor involved but has not been conclusively proven. Other factors include race and gender. Eskimos have a very high prevalence of spondylolysis. At risk are adolescents and children participating in sports such as gymnastics, football linemen, judoists, and new army recruits. The highest incidence of the disease was found in Italian weight lifters in Italy (50%). It has been postulated that the initial fatigue fracture occurs at a young age ( 4% of 7 year old children) and becomes symptomatic in some patients later in life. Not all patients having a fatigue fracture will become symptomatic.
Adolescents and children presenting with back pain should be suspected of having Spondylolysis since it is the most diagnosis. Plain X-rays which include oblique views will show 80% of the lesions. Diagnosis will be difficult in 20% of patients which warrant further studies. Since the lesion is a fatigue fracture, a bone scan is a good initial study. The area of the fracture usually has increased blood flow and the bone scan will be positive. In old standing cases that the blood flow is no longer increased, the bone scan may not detect the lesion. Newer variations to the bone scan are the SPECT Scan. This is the combination of bone scanning with CT scanning and increased the accuracy of the test. Another option is the CT scan itself. Since CT scanning is a good test to visualize bone anatomy, the fatigue fracture may be visualized with this test. MRI scanning is another option, however the accuracy is not as good as CT scanning since the MRI is not as good in detecting bone pathology.
Once the diagnosis of Spondylolysis is made the treatment is almost always non-operative. The patient is prescribed anti-inflammatory medications and is instructed in activity modifications to reduce the stress on the spine. In simple cases that the pain is relieved with these simple modalities, the patient will be able to return to usual activities within 6-8 weeks. Other options may include a spinal brace to provide support while the pain subsides and inflammation resolves. Physical therapy is prescribed after the symptoms resolve and concentrate on endurance training and back muscle strengthening. Follow up X-ray examinations should be performed, especially in the growing child to detect the development of Spondylolisthesis. In some cases one vertebral level will slide over another and cause Spondylolisthesis. Not all Spondylolysis will develop into Spondylolisthesis but this danger is the highest with the growing adolescent.