Humerus, Radius, Ulna Flashcards
Proximal articulation of the humerus
glenoid cavity of the scapula to form the shoulder joint or glenohumeral joint
Distal articulation of the humerus
1) head of the radius
2) trochlear notch of the ulna
forms the elbow joint with the forearm bones
3 main regions of the humerus
1) proximal extremity
2) body or shaft
3) distal extremity
Proximal extremity structures
- head
- greater tubercle
- lesser tubercle
- anatomical neck
- surgical neck
- intertubercular (bicipital groove)
Articulates with the glenoid cavity of the scapula to form the glenohumeral joint in the shoulder joint complex
head of the humerus
oriented medially superiorlly and slightly posteriorly
What are the important relations of the surgical neck?
- axillary nerve
- anterior and posterior circumflex humeral vessels
Forms the interface between the proximal extremity and the shaft of the humerus
Fractures here are common
surgical neck of the humerus
What structure does the intertubercular (bicipital) groove house?
deep groove on the anterior surface of the humerus separating the greater and lesser tubercles
tendon of the long head of the biceps brachii muscles
Structures found in the body/shaft of the humerus
- deltoid tuberosity
- radial groove or spiral groove
- medial supracondylar ridge
- lateral supracondlylar ridge
What attaches to the deltoid tuberosity
deltoid muscle
What structures lie in the spiral groove?
- radial nerve
- profunda brachii vessels
Structures found in the distal extremity
- lateral epicondyle
- medial epicondyle
- capitulum
- trochlea
- coronoid fossa
- radial fossa
- olecranon fossa
What attaches to the lateral epicondyle of the humerus?
common extensor tendon
Inflammation of this tendon is termed: “lateral epicondylitis” or tennis elbow
What crosses the posterior surface of the medial epicondyle
ulnar nerve
in the shallow ulnar sulcus
stimulation of this nerve can elicit a “funny bone” response ehere tingling densations in the medial border of the hand and fifth digit is experienced
What articulates with the head of the radius
Capitulum
forms the humeroradial joint
What part of the humerus articulates with the trochlear notch of the ulna
trochlea
humeroulnar (hinge) joint
Receives the coronoid process of the ulna when the elbow is fully flexed
coronoid fossa
Receives the margin of the head of the radius when the elbow is fully flexed
radial fossa
Holds the apex of the olecranon process of the ulna when the elbow is extended
olecranon fossa
Bone at the lateral side of the forearm
radius
Distal articulation of the radius
- head of the ulna
- scaphoid and lunate bones of the wrists
Structures of the radius
- head
- neck
- radial tuberosity
- body (shaft)
- interosseous border
- ulnar notch
- styloid process
- carpal articular surface
(True/False)
The head of the radius is at the proximal end while the head of the ulna is at the distal end
True
What muscle inserts at the radial tuberosity
biceps brachii muscle
What binds together the radius and the ulna
Interosseous membrane
Articular surface for the head of the ulna
ulnar notch
What articulates to the carpal articular surface
- scaphoid (laterally)
- lunate (medially)
What side can you find the ulna
medial side of the forearm
Distal articulation of the ulna
ulnar notch of the radius
Structures of the ulna
- olecranon
- coronoid process
- trochlear notch
- radial notch
- ulnar tuberosity
- body (shaft)
- head
- styloid process
Forms the head of the elbow
olecranon
What muscle inserts at the olecranon
triceps brachii
Monteggia’s Fracture
- fracture to proximal 1/3 of the ulna
- ant. Dislocation of radial head
Galeazi’s fracture
- fracture of the distal 1/3 of the radius
- subluxation of ulnar head at wrist point
Colle’s fracture
- fracture of distal 1/3 of radius
- posterior displacement of distal radius
Smith’s fracture
Reverse Colle’s fracture
- fracture of distal 1/3 of radius
- volar displacement of the distal radius
