These are some of the best authors in the field of biomechanics. The research facility at the University of Southern California consistently puts out clinically significant studies. This paper is no different as the authors demonstrate that compared to a control group, individuals with patellar tendinopathy exhibit significantly larger tibiofemoral joint internal rotation when performing single-leg landing. In fact, the authors state “transverse plane rotation of the tibiofemoral joint was the best predictor of peak maximum principal stress in the patellar tendon.”

This important paper shows that in order to effectively treat the majority of athletes suffering patellar tendinopathy, you have to address the degree of internal tibial rotation. This can be accomplished with strengthening exercises that target transverse plane stabilizers of the lower extremity and/or using the previously described 2-piece varus posting system to reduce internal tibial rotation. Prior research shows that varus wedges placed beneath insoles can reduce valgus collapse of the knee, and may play a role in preventing anterior cruciate ligament injury.