On the basis of the study results, the full-range translation and rotation cannot differentiate LSI from not LSI and control groups. Moreover, the mid-range translation only differentiates control from LSI, whereas mid-range rotation differentiates control from both LSI and not LSI.

Introduction:The prevalence of Anterior Knee Pain (ANP) has been reported between 15% and 45% in Europe. Muscle weakness is a predisposing factor for ANP. The purpose of this study was to investigate and compare the effect of McKenzie and common exercises on quadriceps and hamstring muscles strengthening and consequently relieving anterior knee pain. Materials and Methods:A total of 22 patients with ANP (Mean [SD] age: 29.191 [1.658] y) were randomly assigned into control and experiment groups. Each group consisted of 11 subjects. The treatment program included hot pack and acupuncture like TENS modalities for 10 sessions. From the third session, the exercise was added to each group's treatment program separately. The control group exercises consisted of strengthening exercises of the knee, thigh and trunk muscles. In the experiment group, the subjects were initially classified according to mechanical diagnostic tests of McKenzie. This classification is based on patient's response to repetitive movements or constant positions at their end range of motion. The exercise was prescribed according to directional preference which was specific for each case. The strength of quadriceps and hamstring muscles were assessed in three stages with hand held dynamometer. The repeated measure ANOVA test was used to compare variables between two groups. The ANOVA and the Tukey post hoc test were used for intra-group comparisons. All statistical analyses were performed in SPSS V. 21. Results:The strength of quadriceps muscle in both groups showed a significant improvement (P<0.001) after the third evaluation. There was no significant difference between the two groups in this regard. There was no significant difference between two groups in hamstring strength among all stages. Conclusion:In patients with ANP, McKenzie exercises like common exercises can improve the strength of quadriceps muscle.