 This is a multi-center, randomized controlled clinical trial, the purpose of which is to determine if patients age 25 and younger who undergo medial patellofemoral ligament MPFL reconstruction have lower rates of recurrent instability compared to those treated non-operatively. The MPFL is a ligament that stabilizes the kneecap, and maintains its proper position in the groove on the femur thighbone. Instability refers to a situation in which the kneecap moves out of place, or dislocates. When instability is recurrent, it occurs more than once in the same knee. 