A Systematic Review of the Effect of Open and Closed Kinetic Chain Exercises on the Vastus Medialis Oblique and Vastus Lateralis Muscles of Patients with Patellofemoral Pain Syndrome

The Patellofemoral pain syndrome (PFPS) is a Retro patellar or per patellar pain caused by Patellofemoral joint modifications of a physical and biomechanical nature. Individuals with painful knees often receive a diagnosis of PFPS [1] which is worsened by performance of activities like stair climbing/descending, squatting or prolonged sitting with knees in a flexed position [1]. This condition has a prevalence of 22/1000 person years and women, particularly those between 18 and 35 years of age Roush and Bay, 2012 are twice as likely to be affected compared to men [2]. Moreover PFPS accompanies a quarter of knee injuries sustained during sports [3] yet no comprehensive understanding has been achieved regarding how this condition develops and how it is classified, diagnosed and treated. However, many researchers have concurred that PFPS is not the outcome of just one, but several causative factors [4] including excessive use, trauma, anatomical aspects, inadequate muscle functioning, and abnormal lower limb alignment [1]. Additionally, quadriceps deficiency or atrophy, especially imbalanced movement of quadriceps components is considered the main biochemical factor underpinning PFPS development, although conclusive evidence has not been produced so far [4].