Wednesday, November 12, 2014

Review Time: Combining Mind and Body!

I think one of the loveliest things about being an artist is simply experiencing life as a member of the art community. As part of this creative and diverse demographic, I've met hundreds of different artists, each with his or her own unique characteristics, both artistically and personally. This year has been no exception, particularly after joining a few different social drawing groups and breathing new life into my personal drawing time. Creating illustrations for clients is one thing— it earns that all important thing known as A Living. But those drawings are for other people, and throughout 20 years or so of making art for other people, I had, to some extent, lost touch with the pleasure of drawing just to draw.

One person I've met recently is the fabulous Kate Citrin, who posed for one of these drawing groups a few months ago. Kate is an expert in Bikram yoga, and she actually held yoga poses while we drew her! Yoga poses like this:


And like this!


And this!!


Yeah.

As you can see, not only were we lucky enough to draw Kate in these poses, but we were also given the opportunity to shoot photos of her to use as drawing references later.

The first thing I thought as Kate effortlessly arranged herself into one elegant posture after another was, "Yeah, I can see pretty much all her muscles and I really want to diagram them all RIGHT NOW." Doesn't everything think this? No? Oh well. I couldn't resist, so my next few posts will focus on this. The wonderful thing about these poses, aside from their yoga-related benefits, is that each one beautifully highlights a specific area of the surface anatomy. Visualizing what's under the skin is a great help to drawing the body's surface appearance.

So let's work our way from the top down! First the posture, called Mermaid:


Next, let's lay in the basic muscle shapes:


Now let's look at the shapes on their own before we zoom in for a closer look.


I've left out the head and face muscles and anything behind the clothing. But we can see anterior neck muscles, arm muscles, abdominal muscles and leg muscles from both medial and lateral views. The labels on the entire image show just how much can be identified. Structures will be identified by these numbers in the close-up views later in this post.



So... let's zoom in to each area for a closer look. We can start with the anterior neck. These close-up images have the structures drawn in. Compare them to the photo up above with no muscles drawn in to see how clearly each shows on the surface. Some are barely visible while some make themselves quite apparent. The clarity of each structure on the body's surface depends on many variables— the amount of body fat on the individual, the position of the body, and even the lighting in the room.



There are three major anterior neck muscles that are commonly visible on the surface. One, the platysma muscle, can't be seen here because it usually only makes itself known when its owner is under strain. Kate pretty much didn't have to strain at all to make it into these poses, so the platysma is not making an appearance. We can, however, see other two prominent anterior neck muscles, the sternocleidomastoid muscle (1) and the sternohyoid muscle (28). Both muscles are named for their origins and insertions (sternocleidomastoid originates on the sternum (sterno-) and the clavicle (cleido-) and inserts on the mastoid process of the temporal bone (mastoid) tucked just behind the ear. The sternocleidomastoid muscles form sort of a V-shape on the anterior neck, while the thiner sternohyoid muscles between them run more parallel to one another down the center of the anterior neck. We can also see the clavicle itself (2) and the acromion process of the scapula, with which the clavicle articulates laterally. Most of the trapezius muscle stretches across the upper back, but one small portion of it can be seen from the anterior side of the shoulders, and a little bit of it is peeking out here (29).

For more on the anterior neck, check out The Anterior Neck: Theme and Variations, and Sternocleidomastoid: Don't Forget the Cleido!

Next let's take a look at the upper arm muscles.


Kate's deltoid muscle (4) is defined nicely on both arms, as is the deltoid furrow-- the crease between the deltoid (4) and pectorals major muscles. You can also see the deltopectoral triangle-- an area at which the deltoid furrow broadens, which appears as a small inverted triangular depression just inferior to the clavicle.

Moving distally from the shoulder, we can see Kate's biceps brachii muscles (6), and, peeking out from behind biceps, the brachialis muscle (7) and the lateral head of triceps brachii (5) peeking out behind that! On Kate's left arm, you can see the long head of her triceps brachii (32) and a TEENY TINY bit of her brachialis on that side (33). Did you notice all these muscle names have the Latin root "brach" in them? That's because this root means "upper arm." Nice, huh? Anatomical terminology is pretty logical. If you'd like, you can read more about that here.

And for more on the upper arm muscles, check out The Deltoid Area: Soft Shoulder and Varied Terrain.

Moving down into the forearm, things get a little crazy.


The forearm is a beautiful, complex arrangement of multiple long, thin muscles, most of which twist gracefully down the arm and taper into long tendons that insert on the various wrist and hand bones. And yes, it's pretty crazy. But that's what makes it so awesome. On both of Kate's arms, we have a good view of most of the extensor/supinators, which lie primarily on the dorsal surface of the forearm, and most of which originate on the lateral epicondyle of the humerus (9), a bony bump on the lateral elbow. The three muscles in this group that we can see most clearly in this photo are the extensor carpi ulnaris muscle(37), the extensor digitorum muscle (36), the extensor digit mimimi muscle (8), and the anconeus muscle (38).

On both forearms, you'll notice the extensor carpi ulnaris muscle (37) lies right up against the crest of the ulna (hence it's name!) and, as we cross over the ulna, we enter the territory of the forearm flexors. These lie mostly on the ventral side of the forearms, which we can't see much of in this photo, but I was able to label two of them-- the flexor carpi ulnaris muscle (39) and the palmaris longus muscle (40) which I can't really see clearly here at all, but I know would be right behind flexor carpi ulnaris from this view… that is IF Kate has this muscle, seeing as it's missing in 12–15% of the human population! 

For more on the elaborate and gorgeous forearm muscles, check out the following links:








Now we can move down to the abdominal muscles, which are among the easiest to see here.


The abdomen has several layers of muscle to compensate for its lack of bony protection, but only two abdominal muscles can be seen clearly on the body's surface. Down the center of the abdomen is the rectus abdominis muscle (42), a muscle known for its six-pack appearance. This segmentation is caused by the linea alba (43), a long midline tendon that bisects rectus abdomens bilaterally, and the interrupting tendons, which run horizontally and divide it up further. 

On either side of the rectus abdomens muscle, we can find the wide, flat external oblique muscles (41), named for their oblique fibers and for the fact that they each have counterpart oblique muscles (that are more internal, and as such are called internal obliques.) There's not much to see in external oblique other than the way it sort of bulges out over the iliac crest, which we can see slightly here.

For more on the abdominal muscles, go to The Anterior Torso Muscles: Peel Away The Layers.

So let's move on to the thighs! 


We have a good view of Kate's anterior and lateral right thigh muscles, starting with the tensor fasciae latae muscle (13), which inserts into the iliotibial band (15), a wide, flat tendon that travels down the lateral thigh. Just anterior to that, we can see most of the muscles of the anterior thigh muscle compartment, including the rectus femoris muscle (20) which is centered over the patella (18) and attaches to it via the quadriceps tendon (shown on the other leg with number 48). Other muscles of the anterior thigh compartment we can see are the vastus lateralis muscle (17) and the sartorius muscle (21), which is the longest muscle in the human body. Just distal to vastus lateralis, we may see or feel a bony lump, which would be the lateral epicondyle of the femur (19).

On Kate's left thigh (to our right) we can see a few medial compartment thigh muscles, including the gracilis muscle (44). Also on her left leg, we can see the remaining anterior thigh compartment muscle, vastus medialis (46) and the medial epicondyle of the femur (47). We can see sartorius on this side as well (45).

For more information on the anterior and medial thigh muscles, check out Batman's Anterior Thigh Compartment and The Lateral Knee: A Change of Scenery. 

Last, let's take a look at the lower legs.


Same image as above, but we'll focus below the knee now. We have a good lateral view of Kate's right leg (to our left) and a good medial view on Kate's left leg (to our right.) Starting with her right leg, we can see both muscles in the lateral leg compartment, the peroneus longus muscle (16) and the peroneus brevis muscle (12). We can also see the lateral head of the gastrocnemius muscle, as well as the soleus muscle (14), which lies just deep to gastrocnemius and peeks out on either side.

We can also see the tendons of both the peroneus longus and peroneus brevis muscles wrapping around the back of the lateral malleolus of the fibula (11). The interesting thing here is that, while both tendons run around the back of the malleolus, that of the peroneus longus show superficially when proximal to the malleolus, but that of the peroneus brevis shows superficially when distal to it! The sort of change places as they run past the malleolous. For more on this check out A Lateral Ankle Tendon: Peroneus Longus or Brevis?

Finally, on Kate's left leg (to our right) we have a good view of the medial leg compartment. We can see the medial head of the gastrocnemius muscle (27) and just about the entire length of the tibia (25). The tibia is completely exposed on its medial side because no muscles obscure it here. The tibia's lateral side, on the other hand, is covered by the tibialis anterior muscle (26), which we can just barely see here. The tibialis anterior muscle is clearly visible on the anterior side of the leg, particularly when the foot is dorsiflexed (pointed up.) Its body, as mentioned above, covers the lateral side of the tibia, but as it extends distally and travels toward the foot, its tendon (24) crosses over to the medial side of the foot and inserts on the distal end of the first metatarsal. We can see that tendon running diagonally across the ankle, especially the foot is dorsiflexed and/or inverted (turned inward.) For more on the tibialis anterior muscle, go to Anterior Leg, Part 2: It's Lonely At The Top.

There are a few more tendons we can just barely see on the dorsal surface of Kate's left foot. Just lateral to the tibialis anterior tendon (24) we can see the extensor hallucis longus tendon, leading directly to its insertion point on the dorsal side of the big toe. Just lateral to that, we can see a few extensor digitorum longus tendons (22) of which there are four; they lead to and insert on all the digits other than the big toe. 

For more information on the dorsal foot, check out How Do I Love Thee? Let Me Count Your Tendons.

I just want to say thanks and HAPPY BIRTHDAY to Kate (yes, this post is going up on her birthday!) and invite you to also check out Kate's blog, Yoga Badassery, Kate and her friend Bleu Caldwell's podcast Pages, and also the wonderful yoga studio, Bikram Yoga Andersonville, to which Kate has introduced me and many others is the recent past. We love you, Kate! 

I hope you enjoyed this review of the entire body. Until next time!


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