Chapter 4 & 5 Positioning

Olecranon process

A beaklike process that curves forward and downward on the proximal end of the ulna. It forms the proximal part of the trochlear notch and it articulates with the olecranon fossa when the elbow is extended.

Styloid Process on the radius

A broad and flattened projection on the lateral surface of the distal end of the radius

Surgical neck

A constricted area of the proximal humerus that lies just below the tuberosities

Olecranon fossa

A deep depression on the posterior surface of the distal humerus. It accommodates the olecranon process when the elbow is extended

Intertubercular groove

A deep depression that delegates the greater and lesser tuberosities

trochlear notch

A half-moon shaped notch formed by the smooth concave surfaces of the olecranon and coronoid processes. it articulates with the trochlea of the humerus.

Greater tuberosity

A large prominence that is located on the lateral surface of the proximal humerus just below the anatomical neck

Head

A large, smooth and round part that lies in an oblique plane on the upper medial side of the proximal humerus. It articulates with the glenoid fossa of the scapula

Coronoid Process

A lower beaklike process that projects forward and upward on the proximal end of the ulna. It forms the distal end of the semi-lunar notch and it articulates with the coronoid fossa when the elbow is flexed.

Lesser tuberosity

A much smaller prominence that is situated on the anterior surface of the proximal humerus just below the anatomical neck

Lateral epicondyle

A prominence that lies directly above the capitalism or lateral condyle

Medial epicondyle

A prominence that lies directly above the trochlea or medial condyle. It is larger and more prominent

Radial Tuberosity

A rough, oval process on the medial and anterior side of the radius, just distal to the neck.

Deltoid tuberosity

A roughened surface on the lateral aspect of the proximal humerus. It lies just below the surgical neck and at the region of the deltoid muscle insertion

Ulnar Head

A round process on the distal end for articulation with the ulnar notch

Coronoid fossa

A shallow depression on the anterior surface of the distal humerus. It accommodates the coronoid process when the elbow is flexed

Radial fossa

A shallow depression on the anterior surface of the distal humerus. Smaller and lateral to the coronoid fossa. It accommodates the radial head when the elbow is flexed

Styloid Process on the ulna

A slender projection on the posterior medial side of the distal ulna

Ulnar Notch

A small depression on the medial aspect of the distal radius for articulation with the head of the ulna

Radial notch

A small, shallow depression on the lateral side of the coronoid process. It articulates with the radial head.

Capitulum

A smooth elevation of the lateral side of the distal humerus. it is actually a condyle and it articulates with the radial head.

Forearm

Consists of two bones

Radial Neck

Constricted area just below the head and above the tuberosity

Joints of the elbow

Diarthrosis, Ginglymus, humeroulnar, humeroradial, proximal radioulnar

Humeral Condyle

Expanded distal end of humerus

Trochlea

It is shaped like a pulley or spool, with two rimlike outer margins and a smooth depressed center portion called the trochlear sulcus. A smooth elevation on the medial side of the distal humerus. It is the medial condyle and it articulates with the semi-lunar notch of the ulna.

Humerus

Largest and longest bone of the upper limb

Distal Humerus Shaft

Long and cylinder-like in shape

Radial Head

Small, flat dislike structure that lies on the proximal end of the radius. Articulates with the ulna at the radial notch.

Ulna

The longest of the two bones in the forearm

Coronoid Tubercle

The medial margin of the coronoid process opposite the radial notch

Anatomical neck

The narrow and constricted area of the proximal humerus that lies just below the head and directly above the tuberosities

Act of Pronation

The radius crosses over the ulna near the upper third of the forearm. This rotation is possible because of the radioulnar joints.