Rectus femoris intrasubstance tear in a collegiate football kicker and its mechanism.

Rectus femoris muscle belly tears have not been reported in the literature to our knowledge. This is a case of an isolated rectus femoris intrasubstance tear in a healthy college football kicker possibly caused by the eccentric and concentric load cycles associated with kicking activities. Dynamic ultrasound was crucial in establishing a diagnosis and investigating the mechanism behind this rare injury.