Kinematic examination of the effect of patellar tendon strap on related anatomic structures

There are studies concerning the anterior knee pain may be resulting from vastus medialis and vastus lateralis muscle contraction speed difference. In some studies, it has been found that vastus medialis muscle contracts later than the vastus lateralis muscle and exercise and bracing decreases pain in patients with patellofemoral pain. As pain has decreased, the difference between vastus medialis and vastus lateralis muscles contraction time has decreased in these patients. Patellar tendon strap is being applied between patella and tuberositas tibia on patellar tendon with some tightness and decreasing patellar tendon derived anterior knee pain. The aim of this study is to design a metodology on healthy volunteers for determining the effect of patellar tendon strap on vastus medialis/ vastus lateralis onset timing and maximal amplitudes during free fall in patients with patellofemoral pain. Four healthy participants attended to the study and they made free fall movement from a 50 centimeter height platform onto a smooth floor. The movement was examined by the help of reflective markers on right lower extremity, fast cameras and EMG system and a methodology was prepared to compare the change of EMG onset, maximum amplitudes and the change in joint angles for both conditions. The maximal EMG amplitudes of RF and VL muscles were decreased for four participants. VM-VL muscle onset timing were different for strap/no strap conditions for all participants. Studies on patellofemoral pain syndrome patients will clarify the effects of strap on pain. Keywords: Patellar tendon strap, anterior knee pain.