Morphological analysis, isometric peak torque and rate of torque development of hip muscles and their relations with the kinematics and kinetics of the lower limb, pelvis and trunk in women with and without patellofemoral pain

Abstract

Although the etiology of patellofemoral pain (PFP) is not yet fully understood, recently factors proximal to the knee joint, such as the weakness of the extensor and abductor hip muscles, have been linked to the PFP. While studies show that subjects with PFP have weakness of the hip muscles, the possible causes of this weakness have not been studied, such as muscle atrophy. In addition to muscle strength, other elements of muscle function, such as rate of force (torque) development, they may be related to PFP. Finally, it is unclear whether the strength and rate of force development of the hip muscles are related to kinematics of the trunk, pelvis and lower limb and lower limb kinetics (joint moments and patellofemoral stress) in subjects with PFP. Thus, the main objectives of this study are to compare the thickness of the gluteus medium and maximum muscles between women with and without PFP; to compare rate of force development of the abductor and extensor muscles of the hip among women with and without PFP; to evaluate the relationship of the maximum isometric torque and rate of force development of the abductor and extensor muscles of the hip with the kinematics of the hip, knee, pelvis and trunk and the kinetics of the lower limb (hip and knee moments, and the patellofemoral stress) during the single-leg squat. Participate in the study 70 women, aged between 18 and 35 years, divided into two groups: group with PFP (n = 35) and control group (n = 35). The thickness and the non-contractile tissue content are measured by means of ultrasound. The lower limb kinematics, pelvis and trunk and lower limb kinetics will be evaluated during single-leg squat using Qualisys system and a Bertec force plate. The maximum isometric torque and the rate of force development will be measured in isokinetic dynamometer Biodex System 3. Multivariate analysis of variance tests will be used to compare the variables measured between groups and correlation statistical tests will be used to assess the relationship between the variables independent and dependent. (AU)