Natasha is 15 years old and is brought into the GP surgery by her concerned mother. She is a keen gymnast and trains 4 times a week. Over the last 4 months her left knee is very painful intermittently, despite no obvious injury. Her mother has read about Osgood-Schlatter disease on the internet and is convinced that she has this.
Which one of the following statements would be least in-keeping with this condition?