Anatomy of the femur

The diaphysis/Shaft of the femur is surrounded by a thick muscular envelope which is divided into three compartments.  The anterior (extensor) compartment for knee extension, the posterior (flexor) compartment for knee flexion and the medial compartment (adductor) for thigh adduction.

The major neurovascular structures are located medially and, therefore, the femur can be safely approached from laterally.  The internervous plane lies along the posterior border of vastus lateralis.