Comparison of Difference of the Gluteus Medius Muscle Fiber Thickness during maximum muscle contraction between Chronic Low Back Pain with Gluteus Medius Weakness and Healthy Subject

Abstract

Fish eye STUDY DESIGN: Controlled laboratory study using a cross-sectional design. Fish eye OBJECTIVES: To determine whether females with patellofemoral pain (PFP) demonstrate differences in hip kinematics, hip muscle strength, and hip muscle activation patterns when compared to pain-free controls. Fish eye BACKGROUND: It has been proposed that abnormal hip kinematics may contribute to the development of PFP. However, research linking hip function to PFP remains limited. Fish eye METHODS AND MEASURES: Twenty one females with PFP and 20 pain-free controls participated in this study. Hip kinematics and activity level of hip musculature were obtained during running, a drop jump, and a step-down maneuver. Isometric hip muscle torque production was quantified using a multimodal dynamometer. Group differences were assessed across tasks, using mixed-design 2-way analyses of variance and independent t tests. Fish eye RESULTS: When averaged across all 3 activities, females with PFP demonstrated greater peak hip internal rotation compared to the control group (mean ± SD, 7.6° ± 7.0° versus 1.2° ± 3.8°; P