Bones and Muscles of the Arm Flashcards
(27 cards)
What are the 3 bones in the Arm called?
The 3 bones in the Arm are called the Humerus, Radius, and Ulna.
What is Supination?
Supination refers to the palm-up position when the Radius and Ulna run parallel to each other.
What is Pronation?
Pronation is when the radius crosses over the ulna at an angle, in order to bring the palm down.
How long is the humerus?
About the same length as the rib cage; two cranial units long.
What is the function of the Humerus?
The humerus has multiple important jobs; it helps the arm move, flex, and rotate. It also holds 13 muscles in place, stabilizing the rest of the arm, including your elbow and hand.
What is the Humerus bone?
The Humerus bone is one of the major bones in the upper arm that provides structure and function.
What is an Epicondyle?
The Epicondyle is a protuberance (extending above the surface) above or on the condyle of a large bone, especially either of the two at the elbow end of the Humerus.
Which side is the Ulna on?
The Ulna is on the medial side of the elbow; the same side as the pinky.
What is the structure of the Ulna?
The Ulna has a slight ‘S’ curve, it is thicker at the elbow and thinner at the wrist.
What is the technical name for the Elbow?
The technical name for the Elbow is the Olecranon.
When do the Epicondyles of the Humerus and the Olecranon line up Horizontally?
When the arm is straight.
What shape does the Olecranon make when the Arm bends?
The Olecranon makes a triangle shape.
How is the hand able to move so freely?
There is a big gap between the ulna and the wrist bones, allowing for more hand movement.
Which side is the Radius located on?
The Radius is always Lateral at the elbow; it is always the thumb side of the wrist.
What is the structure of the Radius?
The Radius is thinner at the elbow, and wider at the wrist. This is opposite to the ulna.
Where does the Brachialis originate from?
The Brachialis originates from the lower half of the Humerus; it starts where the deltoid ended.
Describe the visibility of the Brachialis:
The Brachialis is only visible along the sides of the arm, as the Bicep sits on top of it. Think of it like a muscle sandwich!
Is the Brachialis more visible from the inside of the arm or the outside?
The Brachialis is morevisible on the outside of the arm, its sort of like a little oval.
What is the Biceps Brachii muscle?
The Biceps Brachii is a two headed muscle, it has one Long Head and one Short Head. It is a large, thick muscle on the front portion of the upper arm.
Where does the Long Head of the Biceps Brachii originate from?
The Long Head of the Biceps Brachii originates from the top of the shoulder joint. Its tendon travels over the head of the Humerus and down the Bicipital groove.
Where does the Short Head of the Biceps Brachii Originate from?
The Short Head of the Biceps Brachii originates from the tip of the coracoid process; in the little triangle between the Scapula and the Clavicle.
What bones do the Biceps and Brachialis lead to?
The Biceps lead to the Radius, the Brachialis goes to the Ulna.
What position flexes the Biceps and Brachialis?
When the arm is Supinated (Palm facing up); the Bicep and Brachialis are flexed.
Which direction do the Biceps follow?
The biceps are diagonal in nature.
