Anatomy of the rectus femoris muscle origin in humans, Cebus apella e Alouatta guariba

Abstract

It was realized a anatomic comparative study of rectus femoris muscle between primates that use the biped position, the humans; the quadrupeds, Cebus apella capuchin and the Alouatta guariba howler monkey, all fixed in formaldehyde 10% and carefully dissected. In the humans, the rectus femoris muscle showed one tendon on the anterior inferior spine of the ilium (straight head) and another that surround the superior acetabular ridge of the acetabulum (reflected head). All the specimens showed two tendons of fixation to the rectus femoris muscle, only with origin and structures different.  In 33% of the human sides, a recurrent tendon were observed, the presence of one part that joined by the insertion of gluteus minimus muscle and another that joined by the iliofemoral ligament in the greater trochanter. The recurrent tendon wasn’t found in any specimens. The reflected head is fixed, and the recurrent tendon has the function of make an additional stability to the anterior part of the hip joint. Because of arrangement, length, width and the close relation with the joint capsule can consider that there are distinct levels of importance among fixations of rectus femoris muscle.