The difference in passive tension applied to the muscles composing the hamstrings – Comparison among muscles using ultrasound shear wave elastography

Highlights

• The passive tension applied to hamstrings during passive elongation was examined.

• The passive tension applied to semimembranosus is the highest in hamstring muscle.

• The passive tension applied to hamstring increases with anterior tilt of pelvis.

Abstract

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.

Purpose

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.

Conclusion

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.

Introduction

Hamstring muscle strain is one of the most common injuries in sports (Bishop and Fallon, 1999, Brooks et al., 2006, Gabbe et al., 2006, Feeley et al., 2008, Ekstrand et al., 2011) and results in considerable time lost from training and competition (Brooks et al., 2006, Ekstrand et al., 2011). Many studies have investigated the risk factors and epidemiological features of hamstring muscle strain to identify preventive measures. Some have suggested that hamstring muscle strain is particularly likely to occur during the terminal swing phase of sprinting (Heiderscheit et al., 2005, Schache et al., 2009). The biceps femoris is the most commonly injured muscle among the hamstring muscles (Verrall et al., 2003, Koulouris et al., 2007). A previous study (Thelen et al., 2005) using a computer simulation reported that the percentage change in the length of the biceps femoris muscle tendon unit from standing upright to the terminal swing phase during running was higher than that of the semitendinosus and semimembranosus muscles, and this has been considered one of the reasons for some of the epidemiological features of hamstring muscle strain.

An ultrasound technology, ultrasound shear wave elastography, has enabled us to noninvasively and reliably measure the muscle shear elastic modulus (Bercoff et al., 2004). Previous studies have reported a strong linear relationship between the shear elastic modulus measured using ultrasound shear wave elastography and the passive muscle tension (Maisetti et al., 2012, Chernak et al., 2013, Koo et al., 2013). Therefore, the shear elastic modulus measured using ultrasound shear wave elastography was used as an index of the indirect passive tension. Using this technique, our previous study (Umegaki et al., 2015) reported that the passive tension applied to the semimembranosus was the highest among those applied to the hamstring muscle components at 45° knee flexion and 90° hip flexion. To reveal the cause of this inconsistency, it is important to investigate the in vivo differences in the passive tension applied to the muscles composing the hamstring at the same knee and hip positions as during the terminal swing phase.

The increases in the passive tension applied to the hamstring muscles and in hamstring muscle strain occur mostly during the terminal swing phase of sprinting, in which the hamstring muscle is greatly elongated, in accordance with the hip flexion and knee extension seen in this phase (Yu et al., 2008, Chumanov et al., 2011). If the increase in passive muscle tension during this phase is an important factor in hamstring muscle strain, an anterior or a posterior tilt of the pelvis should likewise be an important factor affecting the passive tension applied to the hamstrings, considering that the hamstring muscles originate from the ischial tuberosity (Abebe et al., 2009). In addition, although the hip joint angle, which is defined as the angle of the trunk with respect to the femur, remains the same, it is possible that the anterior or posterior tilt of the pelvis is different. Therefore, we hypothesized that an anterior tilt of the pelvis can increase the passive tension applied to the hamstring muscles at the same hip joint angle. However, to the best of our knowledge, no study has investigated the effect of pelvic tilt on the passive tension applied to the hamstring muscles.

The aims of this study were to investigate the differences in the passive tension applied to the individual muscles (semitendinosus, semimembranosus, and biceps femoris) composing the hamstrings during passive elongation with the knee and hip angles simulating those seen during the terminal swing phase, and to investigate the effect of pelvic tilt on the passive tension by measuring the shear elastic modulus.