During activities that involve a lot of running, jumping and bending — such as soccer, basketball, volleyball and ballet — your child's thigh muscles (quadriceps) pull on the tendon that connects the kneecap to the shinbone.

This repeated stress can cause the tendon to pull away from the shinbone a bit, resulting in the pain and swelling associated with Osgood-Schlatter disease. In some cases, your child's body may try to close that gap with new bone growth, which can result in a bony lump at that spot.

Feb. 28, 2014

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