An Investigation of the Immediate Effect of Static Stretching on the Morphology and Stiffness of Achilles Tendon in Dominant and Non-Dominant Legs.
This study was undertaken to investigate the immediate effect of static stretching on normal Achilles tendon morphology and stiffness, and the different effect on dominant and non-dominant legs; and to evaluate inter-operator and intra-operator reliability of using shear-wave elastography in measuring Achilles tendon stiffness.



20 healthy subjects (13 males, 7 females) were included in the study. Thickness, cross-sectional area and stiffness of Achilles tendons in both legs were measured before and after 5-min static stretching using grey-scale ultrasound and shear-wave elastography. Inter-operator and intra-operator reliability of tendon stiffness measurements of six operators were evaluated.



Result showed that there was no significant change in the thickness and cross-sectional area of Achilles tendon after static stretching in both dominant and non-dominant legs (p > 0.05). Tendon stiffness showed a significant increase in non-dominant leg (p < 0.05) but not in dominant leg (p > 0.05). The inter-operator reliability of shear-wave elastography measurements was 0.749 and the intra-operator reliability ranged from 0.751 to 0.941.



Shear-wave elastography is a useful and non-invasive imaging tool to assess the immediate stiffness change of Achilles tendon in response to static stretching with high intra-operator and inter-operator reliability.
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
Tsz-Chun Roxy
TC
Chiu
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
Hiu-Ching
HC
Ngo
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
Lai-Wa
LW
Lau
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
King-Wah
KW
Leung
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
Man-Him
MH
Lo
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
Ho-Fai
HF
Yu
Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
Michael
M
Ying
D000125:Achilles Tendon / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D054459:Elasticity Imaging Techniques; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D008297:Male; D052580:Muscle Stretching Exercises; D014463:Ultrasonography; D055815:Young Adult