In contrast to textbooks of anatomy (Moore et al. 2014; Netter 2011; Pabst 2008; Platzer 2013; Schünke et al. 2011) we found a two-layered medial aponeurosis of the vastus intermedius. Thus, it contributed to the deepest as well as to the intermediate layer of the quadriceps tendon. The vastus medialis, as an important dynamic stabiliser against laterally directed forces, inserted in all layers of the vastus intermedius aponeurosis (Figs. 2, 3a and 5). Hence, not only the vastus medialis, but also the vastus intermedius represents a dynamic restraint to lateral tracking of the patella. In contrast to some publications (Andrikoula et al. 2006; Iriuchishima et al. 2012; Sonin et al. 1995; Warwick & Williams 1973; Yablon et al. 2014) the vastus medialis is not directly involved in the architecture of the quadriceps tendon. It inserts into the aponeurosis of the vastus intermedius and tendon of the rectus femoris on its anterior and posterior side.