Investigation into hamstring strains: the case of the hybrid muscle.

Past research on hamstring strains indicated an imbalance in leg strength as a cause of hamstring strains. No theory has been put forth to explain why the strength imbalance would cause strain. Investigation on cadavers of the muscular attachment of the short head of the biceps femoris indicated the varied attachment of this muscle to the linea aspera. It is theorized that an extensive attachment to the linea aspara and a strength imbalance would cause hamstring strains.