The Myotendinous Junction-A Vulnerable Companion in Sports. A Narrative Review.

Jens Rithamer Jakobsen,Michael Rindom Krogsgaard

doi:10.3389/fphys.2021.635561

Jens Rithamer Jakobsen, Michael Rindom Krogsgaard

Open Access

https://doi.org/10.3389/fphys.2021.635561

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Abstract

The incidence of strain injuries continues to be high in many popular sports, especially hamstring strain injuries in football, despite a documented important effect of eccentric exercise to prevent strains. Studies investigating the anatomical properties of these injuries in humans are sparse. The majority of strains are seen at the interface between muscle fibers and tendon: the myotendinous junction (MTJ). It has a unique morphology with a highly folded muscle membrane filled with invaginations of collagen fibrils from the tendon, establishing an increased area of force transmission between muscle and tendon. There is a very high rate of remodeling of the muscle cells approaching the MTJ, but little is known about how the tissue adapts to exercise and which structural changes heavy eccentric exercise may introduce. This review summarizes the current knowledge about the anatomy, composition and adaptability of the MTJ, and discusses reasons why strain injuries can be prevented by eccentric exercise.

Highlights

The transition zone between skeletal muscle and tendon, the myotendinous junction (MTJ), has a key role in being the structure where muscle fibers interact with tendon
During muscle activity and especially during high effort exercise, large forces are transmitted from muscle fibers to the tendon through the MTJ (Huijing, 1999)
To identify studies regarding the structure of the MTJ and strain injuries, the following strategy was used: (Myotendinous junction OR Muscle-tendon interface) AND

Summary

INTRODUCTION

The transition zone between skeletal muscle and tendon, the myotendinous junction (MTJ), has a key role in being the structure where muscle fibers interact with tendon. Force applied to the MTJ can be so extensive, especially during eccentric loading, that strain injuries occur (Garrett, 1996). These are among the most frequent injuries in many popular sports (Orchard and Seward, 2002). There has been a negligible focus on the ultrastructure of the human MTJ, which is where many injuries occur, and how the MTJ adapts to training and inactivity (Mjolsnes et al, 2004; Petersen et al, 2011; Seagrave et al, 2014; Van Der Horst et al, 2015). The review suggests directions for research related to the MTJ in the future

METHODOLOGY

Method of measurement Results

Findings

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