Willis Paull, PhD

A 16-year-old boy complains of right lower leg pain that began 2 weeks earlier, after his first week at a summer basketball conditioning camp. Before he left for the camp, he was jogging off and on, averaging a few miles a week. At camp he began running 7 miles a day and doing sprints 3 times a week.

A 17-year-old boy with no history of foot problems decided to try some new moves with his skateboard on a steep ramp. Midway down the ramp, he tumbled head over heels and landed with most of his weight on his plantar-flexed right foot.

A 12-year-old girl complains of left knee pain and swelling that resulted from a collision with another player while she was playing kickball the day before. Her left foot was planted as she tried to catch a ball, and she was hit on the outside of the left knee. She fell to the ground and was unable to walk on the injured leg; overnight, the knee became more swollen and painful.