About Pars

Athletes are driven with intense training and performance goals. At times young athletes can push themselves harder than their growing bodies can handle as they try to gain a competitive edge.

As athletes pursue excellence, they are rewarded for their discipline and focus — sometimes at a cost. When athletes are under-fueled for their sport and stress their bodies repeatedly, their growing bones can fail them.

Gaining peak performance and the competitive edge through repetitive overuse and without sufficient nutrition, especially during puberty, may lead to Athletic Energy Deficit (AED), a decrease in bone formation and PARS stress fractures.

When viewing the lumbar spine in a anterior oblique view the result is an image which resembles a "Scotty Dog". A fracture of the par interarticularis (isthmus) results on the X-Ray as a dark "collar" on the neck of the dog.


What is PARS stress fracture?

The PARS stress fracture (spondylolysis) usually occurs in the lower back (lumbar spine) and results from repetitive hyperextension (bending backwards) and rotation activities. This fracture is often considered an ?“overuse injury.?” The Pars stress fracture is estimated to occur in 30% of young athletes.

What is a repetitive hyperextension activity?

Athletes who practice sports or activities that involve twisting movements and backward bending are more likely to experience a PARS stress fracture. Sports where hyperextension of the back routinely occurs include gymnastics, diving, football (offensive linemen), pole vaulting, weight lifting, wrestling, dancing, high jumping and volleyball.

What is Athletic Energy Deficit (AED)?

AED is a gap in energy. AED results when high levels of physical activity (energy output) are not balanced with an appropriate diet (energy input). AED often develops when there is pressure to change eating habits, particularly in some sports where a low body weight may be encouraged.

Why Young Athletes?

The years around puberty are a time of rapid bone growth. Girls and boys build 60% to 80% of their bone mass by age 18. During this time, pre-teens and teenagers who do not eat enough to meet their energy needs face an "energy deficit" that can impair proper bone growth. Once bone growth is complete, PARS fractures are rarely seen.

What is the link between AED and PARS?

With insufficient energy intake there may be slower bone formation. Theoretically, insufficient energy leading to slower bone formation combined with repetitive hyperextensions of the back put enormous pressure on developing bones, making them more susceptible to fractures. Left unchecked, AED and poor bone growth may result in more stress fractures and early osteoporosis, a disease where bones become fragile and are more likely to break.


Step 1

Know the Danger

The PARS stress fracture (spondylolysis) usually occurs in the lower back (lumbar spine) and results from repetitive hyperextension (bending backwards) and rotation activities. This fracture is often considered an ?“overuse injury.?” The Pars stress fracture is estimated to occur in 30% of young athletes.

Step 2

Educate young athletes about nutrition and overuse injuries

Early, frequent and open talks about the relationship between healthy eating and bone development can help prevent AED and PARS stress fractures. Work with sports dietitians, team doctors or volunteer medical professionals to discuss the topic with your team.

Step 3

Watch for signs of a problem

Early recognition is important. Pain that gets better with forward bending and worse with extension may be a sign of a more serious problem.

Step 4


Consume enough food to make up for the energy lost during physical activity. Eating adequate carbohydrates and proteins within 20-30 minutes of the most strenuous athletic activity will help replenish the body. But, focus on replacing total calories during the course of the day and prevent the development of Athletic Energy Deficit.

The long term consequences of Athletic Energy Deficit and PARS Stress Fractures can be both severe and potentially permanent. Ignoring them is not worth career-ending injuries.

Building and maintaining bone strength is important in the transition to collegiate or elite athlete training that adds higher intensity stress on the bones.

"You don't have to sacrifice bone health to be a star athlete" says Kathleen Cody, Executive Director of American Bone Health. "All athletes must be educated about the risks of AED and PARS. Nutrition and sports conditioning are crucial for long term bone health."



Lay off of the sport or activity that is causing the pain. A short time of rest may help the bones repair.


Focus on bone strengthening nutrition, especially calcium and vitamin D. Vitamin D is very difficult to get from our normal diet and often requires a supplement. Consume nutrient rich foods and beverages and avoid soft drinks such as soda.


Work with your coach on a program to strengthen your abdominal and most importantly, your gluteal muscle groups. These powerhouse muscles can help protect the spine. The hip flexor, quadriceps and hamstring muscles often get tight in the growing athlete and need to be properly stretched.


Work with your coach or team doctor on how to modify and prevent the overextension and rotation of your spine. Proper technique is essential in all sports and often can greatly reduce the forces on the spine. Don't overdo it and be sure to incorporate overall conditioning.

PARENTS: Talk to your kids about balancing the intensity of their training with proper nutrition and the importance of this to the development of strong bones.

Coaches who are aware of possible symptoms should not hesitate to contact their athlete's parents and tell them about AED, PARS and their health risks.

There are many health benefits associated with regular exercise or athletic competition.

What can a parent or coach do if they suspect PARS? Parents should contact their family doctor immediately. The doctor may perform a one-legged hyperextension test, an x-ray, bone scan or a CT scan.

NOTE: This fracture can be difficult to diagnose.

Nia's Story

Three years ago I was an eighth grader at Mildred E. Strang Middle School in Yorktown Heights, New York. At thirteen years old I was an avid athlete. I held every track record for the school, both boy's and girl's, and was playing basketball with the top high school and even collegiate players in the area. I pushed myself to and past my limits every day, never giving myself a break. By the spring of that year my body was breaking down and during one basketball game it snapped (literally).

As athletes pursue excellence, they are rewarded for their discipline and focus — sometimes at a cost. When athletes are under-fueled for their sport and stress their bodies repeatedly, their growing bones can fail them.

My team was down six with seven minutes left in the second half when I pulled down a rebound. I jumped up for the ball but when I landed I felt something snap- pop- break. I tried running up the court but every step I took sent a searing pain from my lower back down into my leg. It was the first time I had ever cried on the court. My coach took me out right away. The trainer rushed to our bench; he told me to stretch and put heat on my back. He believed I had pulled a muscle. But as I was carried to my car and sent to the emergency room later that night, I realized there was no way this was a pulled muscle. I had broken bones in the past: both my wrists, a couple of fingers, but never had the pain been this bad. I prayed it was nothing serious.

The doctor initially found nothing seriously wrong, and ordered a month of no exercise. A month later, I returned to the season loaded up on painkillers and Bengay, the same searing pain running down my leg. I played one of my best games that year but can hardly remember it; I was in too much pain. My father took me to more and more doctors, trying to figure out what was wrong, but they all said the same thing: that they couldn't find anything and that I should probably just get weekly massages until the pain subsided. But it didn't. Finally, a doctor informed us that I had an inoperable tumor in my spinal canal that was the cause of all my pain. The doctor told me there was nothing he could do, that the worst-case scenario would be paralysis. My father refused to believe it and took me to yet more doctors, who all told us the same thing. They told me that unless I became paralyzed, I could continue to play as long as I could deal with the pain, that I couldn't make the condition worse. So I kept pushing through it.

That summer was one of the most painful for me. I woke up and played basketball every day, with my friends, with my teammates, but the pain never went away and I began dreading having to even walk. There were days when the pain was tolerable and days I couldn't get out of bed. I had to give up soccer because it was too painful to kick the ball; I had to give up running. All I had left was basketball and even that made me cry. Fall soon came. I was entering my first year of high school, and all I dreamt about was making the high school basketball team before it was too late. I woke up every morning to practice by myself, getting ready for tryouts. Finally the week in November came. Tryouts for the '07-'08 varsity basketball season began and I was planning to make it as a freshman, as proof to everybody that a five foot white girl could compete with the best and to prove to myself that I could get through this pain. But as the weeks went on things only got worse. The pain became intolerable, but I had no choice but to play.

When the coach talked to me after the week of tryouts and told me I had made the team I was ecstatic, and the pain subsided. But with our first Saturday morning practice it resurfaced. A week later my dad got a phone call at work from me, telling him that I hadn't been able to walk down the stairs. We went to one last doctor who had me take one last MRI. That night the doctor called our house with the results. He told us he had "good news" for us: the previous findings had been incorrect. I did have a large cyst in my back, but it was completely benign and not causing my problems. However, it had been obscuring what was: I had had two broken bones in my back all along, apparently due to my low bone density levels.

Shortly thereafter I was fitted for a full body cast and then ordered to 2 months of absolutely no activity. After this confinement I returned to sports. A year passed and I felt fully recovered, but something was still wrong. July 2009 I was rushed back to the hospital after collapsing on the court. After an injection of morphine and another MRI I heard devastating news: because of the false diagnosis and the many months playing on a broken back the two bones had not been able to heal. They had healed with fibrous cartilage rather than with bone and thus continuing to play basketball had put too much stress on the fracture site, and the bones re-broke. The doctors claimed there was nothing they could do unless I was willing to consider surgery.

I began the 2009-2010 school year at the Hackley School in Tarrytown, New York: with dreams of a new, pain-free start and a chance to get the years back physically that I had lost. However, on completing the soccer season and half of the basketball season the pain became to great. The surgery was scheduled and I began to mentally prepare for three months of rehab.

It has been a long road back: months in a body cast, even longer in physical therapy, a week in the hospital and now over two months of rehab, all in the hopes of getting back to the physical state I had once been, all in hope of doing the one thing that makes me happy, and that used to be my entire life: basketball. What gets me most is that all of this pain, delay and recovery – torture really -- could have been prevented. When you take a look at the athletic careers of today's youth, you see more and more athletes in my situation: a pars fracture related to over work and over stress. It is my dream to spread awareness of this condition, to stress the importance of taking care of ones body. I want to spread awareness on the importance of healthy bones so that no other athlete has to go through what I did.

Special Thanks

American Bone Health thanks Nia Yancopoulos for her passion to raise awareness about this preventable fracture.

We also thank Gerard Malanga MD, Claude Arnaud MD, Stephen Gomberg MD and Wendy Kohrt PhD for their review of this information.

For more information or to get involved contact American Bone Health at