"Adolescent Back Pain"-Issue 9

About 80% of the population suffers from low back pain at some point in their lifetime. For obvious reasons, athletes are at a greater risk of low back injuries due to the amount of stress and load the spine endures with high impact, repetitive activity. It is estimated that approximately 10-15% of adolescent sport injuries involve the low back/lumbar spine. This incidence is even higher in sports that involve repetitive hyperextension, or arching, of the spine, such as: gymnastics, football, volleyball and swimming.

            Adolescents may be predisposed to back injuries because of muscle imbalances, inflexibility, and structural differences of the spine. As we have discussed in the past, in the growing athlete, the joints have a soft, cartilaginous growth center that is at a higher risk of injury than adults. The joints of the spine are no different.   

In sports that require repetitive backward bending, there is a greater stress placed across this delicate growth center. This amount of stress can increase even more if the athlete develops decreased flexibility during a growth spurt. For instance, tight hip flexors prevent the hips from rotating properly, creating additional stress on the spine during extension. Over time this extra stress may eventually become what is called spondylolysis. 

            Spondylolysis is a stress fracture of the spine caused by repetitive spinal extension and rotation. It is estimated that nearly 50% of adolescent athletes with low back pain results from spondylolysis. 

When this fracture first occurs, pain is not typically severe. The athlete will experience mild complaints of pain across the low back that tends to worsen with arching of the back. Many athletes will ignore this early sign of pain and continue training and competing in sport.

If the athlete chooses to continue, repeated exposure to stress on the spine can cause the fracture to progress into a more serious condition called spondylolisthesis. This condition occurs when the weak area of the bone begins to cause one vertebrae to slip forward over the one below it. The athlete will begin to experience more intense and more frequent pain that may even start to spread down into the legs.

            Both conditions are difficult to diagnose, as they do not always appear on x-rays. This can result in misdiagnosis early on, resulting in improper treatment and potential for the injury to worsen. More extensive imaging such as a bone scan, MRI or CT scan is often required to discover the break/fracture in the spine.

            Once diagnosed, treatment will vary depending on how far the injury has progressed. The primary method of treatment includes rest from sport or activity, allowing time for the fracture to heal. During that time, physical therapy may be recommended to strengthen the abdominal muscles, stretch the muscles of the legs and increase mobility in the low back.

Bracing may also be recommended to relieve pain and prevent further slippage of the vertebrae.  These braces work to flatten out the normal curve of the low back, preventing the athlete from moving into painful extension.  These braces are often worn for several months as the athlete works back toward normal training.

Complete return to sport for these athletes can take time.  Returning to sport with even mild complaints of pain can result in a rapid return to the same injury.  An athlete is considered safe for return if they are pain free and non-reliant on a brace. 

For more information about this injury and others like it, contact your local physician or physical therapist.

References:
1. Kraft DE. Low back pain in the adolescent athlete. Pediatr Clin N Am. 2002; 49:643-53.
2. www.childrenshospital.org
3. Purcell L. Causes and prevention of low back pain in young athletes. Pediatr Child Health. 2009; 14(8):533-535.
4.www.seattlechildrens.org
5.Gerbino PG. Back injuries in the young athlete. Clinics In Sports Medicine. 1995; 14(3):571-596.
6. Nittoli V. Back pain in young athletes. Technique. 2008;14-18.