Kids these days are playing more and more sport and naturally there will be an increase in adolescent injuries. One of the more common adolescent condition is an overuse condition of the knee in young athletes. This is called Osgood Schlatter’s. It usually affects boy aged 11-15 and girls aged 8-13. It has a higher incidence of occurring in sports that require high level of impact and running. It is a apophysitis (normal bony outgrowth, the site of a tendon or ligament attachment) of the tibial tuberosity.