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Basic Anatomy for the Artist

Lesson #7

The Arm and Wrist

The areas of the shoulder and arms are accented to show the main muscles which are working to produce this section. he deltoid has three parts. The anterior part is attached to the clavicle, the middle part is attached to the edge of the acromion and the posterior part to the lower border of the spine of the scapula. Here, the middle muscle bundles are contracting not only to lift his arm but also to produce power
to take her extra weight - or part of it at least.

The anterior muscle bundle, also contracting, are pulling the arm forward. The three parts insert into the deltoid tuberosity of the humerus. The biceps and the brachialis are both contracting to create strong forms as they bend his elbow and maintain joint stability. The brachioradialis, spanning below the lower end of the radius at the wrist to the humerus, is also contracting to flex the elbow. It is called the carrying muscle, as it is used to carry weights.

As a muscle contracts it produces movement. It also gives security to the joint, so it is performing both external and internal work. Some muscles too have to work against gravity as do the muscles at the back of the hip, the front of the thigh, and the back of the leg as they are used to raise one from a sitting position to a standing
one. Therefore they are larger and capable of exerting more power.

When a muscle is being used to lift or sustain a weight against gravity, its optimum angle of pull (when it is acting with its greatest power) is a right angle. When the angle of pull departs from the right angle the internal work of holding the joint together begins to be performed and the lifting power is lessened. In the case of the male dancer who is both lifting and sustaining a position, for a partner, there is a greater
development in those muscles involved. The middle part of the deltoid which is used in raising the humerus, the biceps spanning between the scapula and the radius, which is used to bend (flex) the elbow, the brachialis
spanning between the humerus and the ulna, which is used to flex the elbow, and the brachioradialis spanning from the lower part of the shaft of the humerus to the styloid process of the radius.

LANDMARKS FOR SEATED FIGURE WITH ARMS RAISED.

The olecranon process of the ulna.
The medial epicondyle of the humerus.
The balk of the fleshy part of the triceps muscle and the flattened tendon going toward it's insertion into the olecranon.
The scapular form with the latissimus dorsi over it.
The suprasternal notch.
The convex form of the rib cage.
The anterior superior spines.
The movement of the inguinal ligaments going from the anterior superior spines downward and medially to the pubis. This is the lower line of the abdomen.
The rounded form of the medial condyle of the femur and the sharp edge of the lateral condyle of the femur.
The patella which is shifting slightly to the lateral side when the knee is bent.

All of these landmarks can be felt and seen on yourself.

The light source is from above and to the right of her side. Her left side is in the shadow, side turning away from the light. This includes the side plane of her head and neck, the torso, and areas on the arms and legs. The thighs are almost at a right angle to the torso and so receive light on their upper surfaces.

The shadow is deepened to the edge, with no line used to the edge, in some places on her left side. Reflected light which is not as bright shows the plane under her chin and on her left hip. The light areas which are the same brightness as the background, and her arms and down the right side of her torso are delineated by line. Instead of line one could put in tone to her body edge, or in painting, color.

See you next time!


	The areas of the shoulder and arms are accented to show the main muscles which are working to produce this section. he deltoid has three parts. The anterior part is attached to the clavicle, the middle part is attached to the edge of the acromion and the posterior part to the lower border of the spine of the scapula. Here, the middle muscle bundles are contracting not only to lift his arm but also to produce power to take her extra weight - or part of it at least. The anterior muscle bundle, also contracting, are pulling the arm forward. The three parts insert into the deltoid tuberosity of the humerus. The biceps and the brachialis are both contracting to create strong forms as they bend his elbow and maintain joint stability. The brachioradialis, spanning below the lower end of the radius at the wrist to the humerus, is also contracting to flex the elbow. It is called the carrying muscle, as it is used to carry weights.
	As a muscle contracts it produces movement. It also gives security to the joint, so it is performing both external and internal work. Some muscles too have to work against gravity as do the muscles at the back of the hip, the front of the thigh, and the back of the leg as they are used to raise one from a sitting position to a standing one. Therefore they are larger and capable of exerting more power. When a muscle is being used to lift or sustain a weight against gravity, its optimum angle of pull (when it is acting with its greatest power) is a right angle. When the angle of pull departs from the right angle the internal work of holding the joint together begins to be performed and the lifting power is lessened. In the case of the male dancer who is both lifting and sustaining a position, for a partner, there is a greater development in those muscles involved. The middle part of the deltoid which is used in raising the humerus, the biceps spanning between the scapula and the radius, which is used to bend (flex) the elbow, the brachialis spanning between the humerus and the ulna, which is used to flex the elbow, and the brachioradialis spanning from the lower part of the shaft of the humerus to the styloid process of the radius.
	LANDMARKS FOR SEATED FIGURE WITH ARMS RAISED. The olecranon process of the ulna. The medial epicondyle of the humerus. The balk of the fleshy part of the triceps muscle and the flattened tendon going toward it's insertion into the olecranon. The scapular form with the latissimus dorsi over it. The suprasternal notch. The convex form of the rib cage. The anterior superior spines. The movement of the inguinal ligaments going from the anterior superior spines downward and medially to the pubis. This is the lower line of the abdomen. The rounded form of the medial condyle of the femur and the sharp edge of the lateral condyle of the femur. The patella which is shifting slightly to the lateral side when the knee is bent. All of these landmarks can be felt and seen on yourself.
	The light source is from above and to the right of her side. Her left side is in the shadow, side turning away from the light. This includes the side plane of her head and neck, the torso, and areas on the arms and legs. The thighs are almost at a right angle to the torso and so receive light on their upper surfaces. The shadow is deepened to the edge, with no line used to the edge, in some places on her left side. Reflected light which is not as bright shows the plane under her chin and on her left hip. The light areas which are the same brightness as the background, and her arms and down the right side of her torso are delineated by line. Instead of line one could put in tone to her body edge, or in painting, color.