Key Points ▸ Hip abductor strength is moderately associated with single-leg dynamic balance as measured by the Y-Balance test (YBT). ▸ The association between hip strength and single-leg dynamic balance is strongest during the posterior reaches of the YBT. ▸ The requirement for greater hip flexion
Peter Francis, Kay Gray and Nic Perrem
Richard A. Brindle, David Ebaugh and Clare E. Milner
Weakness of hip abductor muscles during eccentric loading and associated medial collapse have been hypothesized as an etiology of overuse and noncontact injuries, such as patellofemoral pain syndrome 1 and anterior cruciate ligament tears. 2 Furthermore, hip abductor muscle eccentric
Daniel Viggiani and Jack P. Callaghan
-based changes in fatigability in clinical LBP populations appear to be related to altered neural commands to the muscle rather than fiber composition or atrophy. 29 , 30 Since PDs also have altered neural drive to their hip abductors, they may also demonstrate similar fatigue onset and recovery differences as
Gretchen D. Oliver, Jessica K. Washington, Sarah S. Gascon, Hillary A. Plummer, Rafael F. Escamilla and James R. Andrews
further investigation into the role of the hip abductors, specifically the gluteus medius, during throwing. The gluteus medius muscle is a primary hip abductor. The anterior fibers function to internally rotate and abduct the hip, whereas the posterior fibers externally rotate and abduct the hip. 13
Becky L. Heinert, Thomas W. Kernozek, John F. Greany and Dennis C. Fater
To determine if females with hip abductor weakness are more likely to demonstrate greater knee abduction during the stance phase of running than a strong hip abductor group.
Observational prospective study design.
University biomechanics laboratory.
15 females with weak hip abductors and 15 females with strong hip abductors.
Main Outcome Measures:
Group differences in lower extremity kinematics were analyzed using repeated measures ANOVA with one between factor of group and one within factor of position with a significance value of P < .05.
The subjects with weak hip abductors demonstrated greater knee abduction during the stance phase of treadmill running than the strong group (P < .05). No other significant differences were found in the sagittal or frontal plane measurements of the hip, knee, or pelvis.
Hip abductor weakness may influence knee abduction during the stance phase of running.
Jung-Hoon Choi, Heon-Seock Cynn, Chung-Hwi Yi, Tae-Lim Yoon and Seung-Min Baik
dynamic alignment of the lower limbs. 14 Although previous studies have shown that hip muscular strengthening and foot intrinsic strength exercises were effective for ankle and foot stability, no previous studies have applied isometric hip abduction (IHA) for hip stability during SFE. During SFE, the
Mark A. Sutherlin and Joseph M. Hart
Individuals with a history of low back pain (LBP) may present with decreased hip-abduction strength and increased trunk or gluteus maximus (GMax) fatigability. However, the effect of hip-abduction exercise on hip-muscle function has not been previously reported.
To compare hip-abduction torque and muscle activation of the hip, thigh, and trunk between individuals with and without a history of LBP during repeated bouts of side-lying hip-abduction exercise.
12 individuals with a history of LBP and 12 controls.
Repeated 30-s hip-abduction contractions.
Main Outcome Measures:
Hip-abduction torque, normalized root-mean-squared (RMS) muscle activation, percent RMS muscle activation, and forward general linear regression.
Hip-abduction torque reduced in all participants as a result of exercise (1.57 ± 0.36 Nm/kg, 1.12 ± 0.36 Nm/kg; P < .001), but there were no group differences (F = 0.129, P = .723) or group-by-time interactions (F = 1.098, P = .358). All participants had increased GMax activation during the first bout of exercise (0.96 ± 1.00, 1.18 ± 1.03; P = .038). Individuals with a history of LBP had significantly greater GMax activation at multiple points during repeated exercise (P < .05) and a significantly lower percent of muscle activation for the GMax (P = .050) at the start of the third bout of exercise and for the biceps femoris (P = .039) at the end of exercise. The gluteal muscles best predicted hip-abduction torque in controls, while no consistent muscles were identified for individuals with a history of LBP.
Hip-abduction torque decreased in all individuals after hip-abduction exercise, although individuals with a history of LBP had increased GMax activation during exercise. Gluteal muscle activity explained hip-abduction torque in healthy individuals but not in those with a history of LBP. Alterations in hip-muscle function may exist in individuals with a history of LBP.
Cale Jacobs and Carl Mattacola
Decelerating movements such as landing from a jump have been proposed to be a common mechanism of injury to the anterior cruciate ligament (ACL).
To compare eccentric hip-abductor strength and kinematics of landing between men and women when performing a hopping task.
18 healthy subjects (10 women, 8 men).
Main Outcome Measures:
Eccentric peak torque of the hip abductors and peak knee-joint angles during a 350-millisecond interval after impact.
No significant sex differences were present, but there was a significant inverse relationship between women's eccentric peak torque and peak knee-valgus angle (r = –.61, P = .03).
Women with larger eccentric peak torque demonstrated lower peak knee-valgus angles. By not reaching as large of a valgus angle, there is potentially less stress on the ACL. Increasing eccentric hip-abductor strength might improve knee-joint kinematics during landing from a jump.
Jensen L. Brent, Gregory D. Myer, Kevin R. Ford, Mark V. Paterno and Timothy E. Hewett
As high school female athletes demonstrate a rate of noncontact anterior cruciate ligament (ACL) injury 3–6 times higher than their male counterparts, research suggests that sagittal-plane hip strength plays a role in factors associated with ACL injuries.
To determine if gender or age affect hip-abductor strength in a functional standing position in young female and male athletes.
Prospective cohort design.
Over a 3-y time period, 852 isokinetic hip-abduction evaluations were conducted on 351 (272 female, 79 male) adolescent soccer and basketball players.
Before testing, athletes were secured in a standing position, facing the dynamometer head, with a strap secured from the uninvolved side and extending around the waist just above the iliac crest. The dynamometer head was positioned in line with the body in the coronal plane by aligning the axis of rotation of the dynamometer with the center of hip rotation. Subjects performed 5 maximum-effort repetitions at a speed of 120°/s. The peak torque was recorded and normalized to body mass. All test trials were conducted by a single tester to limit potential interrater test error.
Main Outcome Measure:
Standing isokinetic hip-abduction torque.
Hip-abduction torque increased in both males and females with age (P < .001) on both the dominant and nondominant sides. A significant interaction of gender and age was observed (P < .001), which indicated that males experienced greater increases in peak torque relative to body weight than did females as they matured.
Males exhibit a significant increase in normative hip-abduction strength, while females do not. Future study may determine if the absence of similar increased relative hip-abduction strength in adolescent females, as they age, may be related to their increased risk of ACL injury compared with males.
James W. Youdas, Erica F. Loder, Jody L. Moldenhauer, Christine R. Paulsen and John H. Hollman
Hip-abductor weakness is associated with many lower extremity injuries. A simple procedure to assess hip-abductor performance is necessary in patient populations.
To describe the change in pelvic-on-femoral position of the stance limb before and after 45 seconds of resisted sidestepping.
24 healthy women (24.6 ± 3.5 years) and 14 healthy men (24.5 ± 3.0 years).
Main Outcome Measures:
Pelvic-on-femoral position in degrees in single-leg stance before and after 45 seconds of resisted sidestepping.
The difference between the baseline and postexercise measurements for both men and women was significant (P < .05). The effect of the resisted-sidestepping exercise on the hip abductors was not statistically different between men and women.
Forty-five seconds of resisted sidestepping using an elastic band produced a change in pelvic-on-femoral position in healthy adults. This test might be useful to detect impaired performance in hip abductors of patients with injury elsewhere in the musculoskeletal system.