This is a partial separation of the tibia tuberosity. It is also apophysitis (inflammation) of the tibial tuberosity. This condition is caused by sudden or continued strain placed upon the tuberosity by the patellar ligament during exercise. The inflexibility of the quadriceps, especially the rectus femoris and vastus lateralis, is a major cause of the strain which leads to a stress fracture. This is frequently repeated over and over, healing with recalcification, until the condition is corrected. Repeated deceleration of the quadriceps during the landing phase after running or jumping is a leading cause.

A program of AIS stretching including the hamstrings, quadriceps, IT band, and calves. AIS strengthening of the quadriceps employing straight leg raise, and short arc extension held for 5 seconds, hip adduction, hip abduction and straight leg hip hyperextension.