How Will Lesion Affect Growth In Leg/knee?

My daughter is 12 she plays football and cricket regularly, she complains of a pain in her knee, and says it feels like a bubble. was told she has a lesion on the growth plate and that it is not (please excuse spelling) Osgute schlasen?! Can you please explain what a lesion is and how it will affect the growth in her leg/knee? she rested for 14 days but it still flairs up. Thank you