Variability in Biceps Femoris Long Head Muscle-Tendon Morphology

INTRODUCTION The biceps femoris long head, one of the muscles of the hamstrings group, is one of the most commonly injured lower-limb muscles. Previous studies have suggested that aponeurosis morphology influences injury susceptibility in muscle [1]. In that study, a model of the biceps femoris long head muscle predicted that the width of the muscle’s proximal aponeurosis greatly affects localized tissue strains and therefore injury susceptibilities. However, it is currently unknown how much variability in aponeurosis morphology exists in the normal population. In the present work, we used magnetic resonance imaging (MRI) to characterize how muscle volume, proximal external tendon cross sectional area, and proximal aponeurosis width of the biceps femoris long head muscle vary across a group of healthy subjects.