Dr. Joseph Donahue is an orthopedic surgeon at SOAR Clinic in Redwood City and has served as team physician for the San Francisco 49ers and Stanford University as well as an orthopedic consultant for the San Francisco Giants. He is the team physician for Santa Clara University.

Here, Dr. Donahue examines the rise in ACL injuries among younger athletes. He cites year-round play and overuse as the culprits and explains how fatigue can contribute to an athlete's susceptibility to ACL problems. He also explains some preventative measures in terms of core strength and hip flexibility.