Forty-one knees from adult cadavera (twenty female and twenty-one male)
were dissected to study the relationship between the longitudinal axis of
the patella and the angles of insertion into it of the vastus lateralis and
vastus lateralis obliquus muscles. The mean and variance in the angles of
insertion of the vastus lateralis obliquus tendon were found to be
significantly different between men and women (p less than 0.05 and p less
than 0.01, respectively). Three distinct anatomical patterns in the
insertion of the vastus lateralis obliquus muscle were delineated. The
vastus lateralis muscle, particularly the vastus lateralis obliquus,
creates an important lateral force-vector on the patella.