A Drawing A Day 1263

Progress Shot 03

The three muscles drawn below are:
1/ Biceps Femoris
Action: Extends thigh at hip joint, flexes and laterally rotates leg.

2/ Semimembranosus
Action: Extends thigh at hip joint, flexes and medially rotates leg.

3/ Semitendinosus
Action: Extends thigh at hip joint, flexes and medially rotates leg.

Graphite and White Chalk on prepared Canson Mi–Teintes paper, 55 x 37cm

A Drawing A Day 1247

Progress Shot 04

So we have our 4 views, Anterior, Lateral, Posterior and Medial. The top row shows only the bones and one of the new muscles. However it does so as if the rest of the muscles were around, just invisible. So the muscle is moulded around the other muscles. The bottom row shows the same 4 views of the thigh, but this time all the muscles visible on the surface are drawn in.
The other 2 new muscles, the Gracilis and Sartorius are both surface muscles, entirely visible including their origin and insertion points, so I did not see a need to draw them individually with the bones alone. Here are the muscles we had so far, plus the new ones:

1/ Vastus Lateralis
Action:
 Extends leg at knee joint.

2/ Vastus Medialis
Action: Extends leg at knee joint.

3/ Rectus Femoris
Wedged between the Vastus Lateralis and Vastus Medialis is the third of the 4 muscles of the Quadriceps Group, Rectus Femoris. Directly underneath it is the fourth muscle of this group, Vastus Intermedius which also extends the leg at knee joint.
Action: Extends leg at knee joint, flexes thigh at hip joint.

4/ Adductor Longus
Action: Adducts and contributes to flexing the thigh at hip joint.

5/ Illiacus
Action: Flexes and rotates laterally the thigh at hip joint, stabilises the hip joint.

6/ Psoas Major
Action:
 Flexes and rotates the thigh laterally at hip joint.

7/ Gracilis
Action: Adducts and flexes thigh at hip joint, flexes and medially rotates leg at knee joint.

8/ Adductor Magnus
Action: Adducts, flexes and laterally rotates thigh at hip joint. Hamstring part medially rotates and extends thigh.

9/ Sartorius
Action: Abducts (abduction is not to be confused with adduction), laterally rotates and flexes thigh at hip joint, flexes and medially rotates leg at knee joint

I spoke earlier of grouping the muscles for both, an easier understanding of function and an easier depiction. So far we have seen 2 major groups on the thigh: the Adductor group which consists of the Adductor Magnus, Adductor Longus and Gracilis. They all adduct as they main function.
The second group is the Quadriceps group which consists of the deep layer Vastus Intermedius and surface layer Vastus Lateralis, Rectus Femoris and Vastus Medialis. Again, with slight differences they perform the same function of extending the leg. The muscles which mostly perform extension are also called Extensors.

Ok, next, a few examples of the above list of muscles and then there are a few more on the thigh we need to mention as they significantly contribute to the shape of the leg and to the expressions we can achieve by depicting them in either contracted or relaxed states.

Graphite and White Chalk on prepared Canson Mi–Teintes paper, 55 x 37cm