The difference in passive tension applied to the muscles composing the hamstrings - Comparison among muscles using ultrasound shear wave elastography.
BACKGROUND
Hamstring muscle strain is one of the most common injuries in sports. Therefore, to investigate the factors influencing hamstring strain, the differences in passive tension applied to the hamstring muscles at the same knee and hip positions as during terminal swing phase would be useful information. In addition, passive tension applied to the hamstrings could change with anterior or posterior tilt of the pelvis.


OBJECTIVE
The aims of this study were to investigate the difference in passive tension applied to the individual muscles composing the hamstrings during passive elongation, and to investigate the effect of pelvic position on passive tension.


METHODS
Fifteen healthy men volunteered for this study. The subject lay supine with the angle of the trunk axis to the femur of their dominant leg at 70° and the knee angle of the dominant leg fixed at 30° flexion. In three pelvic positions ("Non-Tilt", "Anterior-Tilt" and "Posterior-Tilt"), the shear elastic modulus of each muscle composing the hamstrings (semitendinosus, semimembranosus, and biceps femoris) was measured using an ultrasound shear wave elastography.


RESULTS
The shear elastic modulus of semimembranosus was significantly higher than the others. Shear elastic modulus of the hamstrings in Anterior-Tilt was significantly higher than in Posterior-Tilt.


CONCLUSIONS
Passive tension applied to semimembranosus is higher than the other muscles when the hamstring muscle is passively elongated, and passive tension applied to the hamstrings increases with anterior tilt of the pelvis.
Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan; Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan. Electronic address: masatoshi-nakamura@nuhw.ac.jp.
Masatoshi
M
Nakamura
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Satoshi
S
Hasegawa
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Hiroki
H
Umegaki
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Satoru
S
Nishishita
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Takuya
T
Kobayashi
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Kosuke
K
Fujita
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Hiroki
H
Tanaka
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Satoko
S
Ibuki
Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan.
Noriaki
N
Ichihashi
D000328:Adult; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods; D000070633:Hamstring Muscles / Q000293:injuries* / Q000502:physiology*; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000502:physiology; D006801:Humans; D007717:Knee / Q000000981:diagnostic imaging / Q000502:physiology; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D052580:Muscle Stretching Exercises; D009129:Muscle Tonus / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D010388:Pelvis / Q000000981:diagnostic imaging / Q000502:physiology; D016059:Range of Motion, Articular / Q000502:physiology*; D014463:Ultrasonography
Hamstrings; Pelvis; Shear wave elastography