Human leg the anterior superior iliac spine to the pes anserinus on the medial side of the knee, from where it is further extended into the crural fascia. The sartorius acts as a flexor on both the hip and knee, but, due to its oblique course, also contributes to medial rotation of the leg as one of the pes anserinus muscles (with the knee flexed), and to lateral rotation of the hip joint. There are four posterior thigh muscles. The biceps femoris has two heads: The long head has its origin on the ischial tuberosity together with the semitendinosus and acts on
Articular capsule of the knee joint the suprapatellar bursa is seemingly redundant. It is however also referred to as the "suprapatellar synovial recess" as it gradually unfolds as the knee is flexed; to open up completely when the knee is flexed 130 degrees. The suprapatellar bursa is prevented from being pinched during extension by the articularis genus muscle. On the tibia, the anterior reflection and attachment of the synovial membrane is located near the cartilage. Anteriorly, the infrapatellar fat pad is inserted below the patella and between the two membranes. It extends from the lower margin of the patella above, to the infrapatellar synovial fold below.