Effects of the trunk position on muscle stiffness that reflects elongation of the lumbar erector spinae and multifidus muscles: an ultrasonic shear wave elastography study
The present study aimed to clarify the effects of the trunk position on muscle stiffness that reflects elongation of the lumbar erector spinae and lumbar multifidus muscles using ultrasonic shear wave elastography (SWE).
The study included ten healthy men. The shear elastic modulus of the left lumbar erector spinae and lumbar multifidus muscles were evaluated using ultrasonic SWE. Measurement postures for the left lumbar erector spinae muscle were (1) prone position (Rest), (2) sitting position with the trunk flexed (Flexion), (3) the Flexion position adding right trunk lateral flexion (Flexion-Lateral Flexion), and (4) the Flexion position adding right trunk rotation (Flexion-Rotation 1). The left lumbar multifidus muscle were measured in positions (1)–(3), and (5) the Flexion position adding left trunk rotation (Flexion-Rotation 2).
The shear elastic modulus of the lumbar erector spinae muscle in the Flexion-Lateral Flexion position was significantly higher than that in the Rest, Flexion, or Flexion-Rotation 1 positions. Shear elastic modulus of the lumbar multifidus muscle was similar in the Flexion, Flexion-Lateral Flexion, and Flexion-Rotation 2 positions, but significantly lower in the Rest position.
The results of the present study suggest that the lumbar erector spinae muscle is stretched effectively in the position adding trunk contralateral lateral flexion to flexion. The results also indicate that the lumbar multifidus muscle, which does not appear to be affected by adding trunk contralateral lateral flexion or ipsilateral rotation to flexion, is stretched effectively in the trunk flexion position.
KeywordsParaspinal muscles Muscle elongation Muscle stiffness Ultrasonography
Intraclass correlation coefficient
Low back pain
Region of interest
Shear wave elastography
This study was supported by the Grant-in-Aid for Scientific Research (B) 15H03043. The authors wish to thank all of the individuals who participated in the present study.
All authors conceived and designed the research. MM, XJ, and TY conducted experiments. MM and XJ analyzed data. MM, HT, and NI wrote the manuscript. All authors read and approved the manuscript.
Compliance with ethical standards
Conflict of interest
On behalf of all authors, the corresponding author states that there is no conflict of interest. No funding sources were used for the present study.
- Chaffin DB, Redfern MS, Erig M, Goldstein SA (1990) Lumbar muscle size and locations from CT scans of 96 women of age 40 to 63 years. Clin Biomech (Bristol, Avon) 5, 9–16Google Scholar
- Kelly JP, Koppenhaver SL, Michener LA, Proulx L, Bisagni F, Cleland JA (2018) Characterization of tissue stiffness of the infraspinatus, erector spinae, and gastrocnemius muscle using ultrasound shear wave elastography and superficial mechanical deformation. J Electromyogr Kinesiol 38:73–80CrossRefGoogle Scholar
- Masaki M, Aoyama T, Murakami T, Yanase K, Ji X, Tateuchi H, Ichihashi N (2017) Association of low back pain with muscle stiffness and muscle mass of the lumbar back muscles, and sagittal spinal alignment in young and middle-aged medical workers. Clin Biomech (Bristol Avon) 49:128–133CrossRefGoogle Scholar
- Umehara J, Hasegawa S, Nakamura M, Nishishita S, Umegaki H, Tanaka H, Fujita K, Kusano K, Ichihashi N (2017a) Effect of scapular stabilization during cross-body stretch on the hardness of infraspinatus, teres minor, and deltoid muscles: an ultrasonic shear wave elastography study. Musculoskelet Sci Pract 27:91–96CrossRefGoogle Scholar