Relationship Between Hip Muscle Strength and Kinematics of the Knee Joint during Single Leg Squatting and Dropping

Abstract

Abstract.[Purpose] The aim of this study was to determine relationship between hip muscle strength and kinematics of the knee joint during single leg squatting and dropping.[Subjects] Twelve healthy subjects participated in this study.[Methods] The knee medial displacement was measured during single leg squatting and dropping using a highspeed camera. Peak isometric muscle strengths of the following muscles were measured hip abductors, hip adductors, hip external rotators, hip internal rotators, knee extensors and knee flexors.[Results] Muscle strength of hip external rotators was associated with knee medial displacement during both single leg squatting (r=-0.69) and dropping (r =-0.59), and muscle strength of knee flexors was associated with knee medial displacement during dropping (r = -0.58).[Conclusion] The present results suggest that hip muscles' strength, particularly hip external rotators' strength are closely associated with knee medial displacement.

The refinement and validity evaluation of a 2-Dimensional motion capture method to quantify lumbo-pelvic-hip complex motion in chronic low back pain

“…There was an overall lack of evidence for the relationship between maximal hip muscle strength (especially abduction and extension) and test performance [143,169,173,175,179,184,185,191,192,[194][195][196]. Only hip external rotation strength was found to have strong evidence of relationship with test outcome (frontal plane knee movement) during the SLSQUAT test [143,184,185,192,195].…”

“…Evidence of correlation between maximal hip abduction strength and frontal plane knee kinematics was conflicting. Although most studies showed no relationship [143,169,185,191,192,194,195], three showed low to moderate correlations between hip abduction strength and knee valgus movement [184,185,195]. Conflicting evidence was found for correlations between hip abduction strength and hip adduction angle (negligible non-significant correlations in one study, moderate negative correlations in another) [173,184].…”

“…Limited evidence was found that isokinetic hip extension and abduction strength was not related to frontal plane knee angles [169,192]. There was inconclusive evidence that maximal hip external rotation strength demonstrated moderate negative correlations with medial knee displacement angle during the SLDROP [192] test.…”

“…Limited evidence was found that isokinetic hip extension and abduction strength was not related to frontal plane knee angles [169,192]. There was inconclusive evidence that maximal hip external rotation strength demonstrated moderate negative correlations with medial knee displacement angle during the SLDROP [192] test. Limited evidence was found that maximal hip extension and abduction strength was related to the magnitude and velocity of trunk bending in some, but not all planes of motion, during the SLDROP test [196].…”

“…There was strong evidence that maximal hip extension strength was not associated with frontal plane knee kinematics during SLSQUAT [169,185,191]. In contrast, strong evidence was found for a low to moderate correlation between hip external rotation strength and medial frontal plane knee movement [143,184,185,192,195]. Limited evidence was found for a low correlation between eccentric hip external rotator torque and femoral adduction or lateral pelvic tilt excursions [184].…”