Patellofemoral pain syndrome is one of the most common musculoskeletal disorders in young adults. The pain existing in anterior knee or posterior patellar without other knee pathologies is called patellofemoral pain syndrome. In prospective studies the prevalence of this disease is reported to be 7% in active young adults and 15% in military staff. Although the main cause of this syndrome is unknown, some researchers believe that the pain can be attributed to some biomechanical, soft tissue or muscle abnormalities. This syndrome causes pain and functional disorder in the corresponding patients and if not treated well, it may result in chronic pain and/or weaknesses in quadriceps muscles.
In the studies conducted so far, a variety of treatments including low power laser, orthoses, ultrasonography and rehabilitative exercises has been investigated while none of them has been proved to be significantly effective. Moreover, despite the growing use of high power lasers in alleviating musculoskeletal pains and its confirmed physiologic effects, studies investigating the effect of high power laser in pain management and function of patients with patellofemoral pain syndrome are very limited. Thus, the focus of this study is on analyzing the efficacy of high power laser in treatment of patients with patellar chondromalacia. To do so, a double blinded randomized clinical trial for the new treatment is designed in order to compare the efficacy of high power laser with the control group of isometric knee exercise, as the standard treatment for patellofemoral pain syndrome.
In this study, 44 patients from PM&R clinic of Modarres and Shohada hospitals diagnosed with patellofemoral pain syndrome by clinical tests (Shrug test, Grind test,Perkins test) having the symptoms for three months with normal AP , lateral and patellar view knee xray are selected and divided into control and intervention groups, randomly. Five session of high power laser in 2 weeks along with training isometric knee exercises are carried out on the intervention group. On the other hand, the control group undergoes 5 sessions of sham laser in 2 weeks accompanied by training isometric knee exercises. To evaluate and compare the two groups, the outcome of treatments will be measured by VAS score, WOMAC and kujala questionnaires. These measurements will be performed before intervention and 1 and 3 months after intervention.