Hamstring muscles rupture under traction, peeling and shear lap tests: A biomechanical study in rabbits. (April 2021)

• Record Type: Journal Article
• Authors: Pillet, Baptiste; Badel, Pierre; Edouard, Pascal; Pierrat, Baptiste
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 116(2021)
• Publication Date: 2021-04
• Subjects: Hamstring muscles -- Rupture test -- Energy release rate -- Muscle injury -- Peeling test -- Shear lap test; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2021.104324
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: Lesions of the Musculotendinous Unit (MTU, i.e. tendon, myotendinous junction, muscle, aponeurosis and myoaponeurotic junction) are a common injury and a leading cause of functional impairment, long-term pain, and/or physical disability worldwide. Though a large effort has been devoted to macroscopic failure evaluation, these injuries suffer from a lack of knowledge of the underlying tissue-scale micro-mechanisms triggering such lesions. More specifically, there is a strong need for experimental data to better understand and quantify damage initiation and propagation on MTUs. The present study presents original experimental data on muscle tissue extracted from the hamstring muscle group of rabbits under relevant mechanical solicitations up to rupture, revealing elementary micro-mechanisms and providing quantified values of elastic properties as well as initiation stress and energy release rate. More specifically, tensile, peeling and shear lap tests were performed to explore cohesion of muscle tissue along the fibre direction or across fibres (mode I) and in shear (mode II), as well as at the muscle/tendon interface. We show that muscle tissue is weaker in shear than tension ( p -value < 0.01) and that the Biceps Femoris had the lowest energy release rate as calculated from mode I peeling tests (G = 0.23 ± 0.16 N/mm) compared to the Semi-Membranous (G = 0.53 ± 0.08 N/mm) and the Semi-Tendinous (0.45 ± 0.20 N/mm), and that this energy is the lowest at the musculotendinous junction. Our study suggests a preferred damage initiation mechanism based on fibre decohesion in mode I or II and provides quantitative data to model these phenomena. Results also suggest that the Biceps Femoris and more precisely its musculotendinous junction could be the weakest point of the hamstring group. These findings could be used as a basis to develop mechanical models (e.g. finite element) to better understand and predict the onset of hamstring lesions and help in preventing such events. Graphical abstract: Highlights: Experimental rupture tests were performed on rabbit hamstring muscle. Mode I and mode II, in fibre and cross-fibre directions were investigated. Muscle tissue was weaker in shear (mode II) than tension (mode I) : p -value ¡ 0.01. Biceps Femoris (BF) had the lowest energy release rate from peeling tests (mode I). Results suggest that the BF could be the more at risk from hamstring group injuries.