Fig. 1
![Fig. 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40634-021-00422-2/MediaObjects/40634_2021_422_Fig1_HTML.png)
Posterior aspect of a knee joint. A Posterior view of the femur; B Posterior view of the femur, showing the location of the femoral attachment of the posterior capsule of the knee joint with stainless pins; C After excision of the gastrocnemius muscle. 1: lateral head of the gastrocnemius tendon; 2: medial head of the gastrocnemius tendon: 3: biceps femoris muscle; 4: semimembraneous muscle; 5: posterior aspect of the femur; 6: posterior capsule of the knee joint