Effects of lower extremity posture on hip strength and their influence on lower extremity motion during a single leg squat

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Anh Dung Nguyen, PhD (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/
Advisor
Sandra J Shultz

Abstract: "This research investigated the effects of static lower extremity posture on hip strength, and then examined their collective influence on knee and hip joint kinematics during a single leg squat in males and females. Thirty one healthy males and 31 healthy females, predominantly college students, between the ages of 18 and 35 participated in a single data collection session during which six lower extremity posture characteristics were measured, followed by measurement of hip abduction and extension strength and concluded with neuromuscular and kinematic analysis of the hip and knee during a single leg squat. Hip torque was normalized to body mass and electromyographic data were normalized to maximum voluntary isometric contractions. Five single leg squats were performed on the dominant stance limb to a depth of 60° of knee flexion. Path analysis, implemented by structural equation modeling, was used to examine whether greater lower extremity posture characteristics predicted decreased hip torque and whether greater lower extremity posture characteristics and decreased hip torque collectively predicted greater dynamic valgus knee motion (increased hip adduction and internal rotation, and knee external rotation and valgus). Separate multivariate analyses of variance determined whether females and males differed on measures of lower extremity posture, hip strength, and total hip and knee motion during the single leg squat. The findings were that greater hip anteversion predicted decreased hip abduction torque, and greater tibiofemoral angle predicted decreased hip extension torques. Direct relationships were noted between greater hip anteversion and genu recurvatum with greater knee external rotation, and between greater navicular drop and hip anteversion with greater hip internal rotation during the single leg squat. Furthermore, decreased hip abduction torque predicted greater knee external rotation while decreased hip extension torque predicted greater knee valgus during a single leg squat. Hence, it was concluded that greater lower extremity posture characteristics predicted decreased posterio-lateral hip strength, and collectively, greater lower extremity posture characteristics and decrease posterio-lateral hip strength predicted greater functional valgus collapse during the single leg squat."--Abstract from author supplied metadata.

Additional Information

Publication
Dissertation
Language: English
Date: 2007
Keywords
static, lower extremity, posture, hip strength, influence, knee, kinematics, leg squat, males, females
Subjects
Hip joint--Muscles
Leg--Movements
Posture