humerous Flashcards
(2 cards)
the arm
The head of the humerus is rounded and fits into the glenoid cavity of the scapula, forming a ball-and-socket joint.
The anatomical neck of the humerus has a slight narrowing just below the rounded head.
greater and lesser tubrecules act as the attachment part for muscles and is seperated by the intercubital sulcus.
The surgical neck lies just below the tubercles and is the most frequently fractured part of the humerus.
The deltoid tuberosity is a rough patch on the side of the humerus shaft, where the deltoid muscle attaches.
The radial groove runs down the posterior side of the humerus and marks the path of the radial nerve.
The capitulum is ball-shaped and connects with the radius.
The coronoid process of the ulna fits into the coronoid fossa of the humerus when you bend your elbow.
The olecranon fossa is a deep depression at the back (posterior) of the humerus, and it “catches” or receives the olecranon process of the ulna when you straighten your elbow.
Medial epicondyle = “funny bone” area (because the ulnar nerve runs nearby, and when hit, causes that tingling sensation).
Lateral epicondyle = attachment for muscles that help extend the wrist and fingers.
the radius and ulna
In the anatomical position (standing straight, palms facing forward),
The radius is on the thumb side (lateral side) of the forearm.
The ulna is on the little finger side (medial side).
When you rotate your hand so the palm faces backward (this movement is called pronation),
The radius crosses over the ulna and ends up on the medial side (closer to the body).
The ulna stays mostly in place on the medial side.
so proximal and distal radioulnar joints connect the ulnar and radial at the end
The interosseous membrane is a flexible “web” between the radius and ulna that keeps them aligned and gives muscles a place to attach.
the disc shaped head articulates with the captilulium of the humerous
Just below the head is the radial tuberosity, where the biceps tendon attaches.
Proximal end has two processes:
Coronoid process (anterior/front)
Olecranon (posterior/back; the “tip” of your elbow)
These are separated by the trochlear notch, a curved depression that “grips” the trochlea of the humerus, forming a tongue-in-groove joint (very stable hinge joint for the elbow).
