Elbow: Anatomy

Elbow: Anatomy

Bony Anatomy Radius  Ulna  Humerus – 2 condyles 

◦ Lateral – capitulum  Articulates with the radius

◦ Medial – trochlea  Articulates with humerous

Ligaments ◦ Ulnar collateral  Medial epicondyle to ulnar trochlear notch  Strong anterior band, weaker transverse & middle  Gives medial support

◦ Radial collateral  Lateral epicondyle to side of annular ligament  Does not attach to radius  Gives lateral support

◦ Annular  Holds radius to ulna and humerus  Allows rotation of radius (supination and flexion)  Gives lateral support

Muscles 

Flexion ◦ Biceps brachii, brachial, brachioradialis

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Extension ◦ Triceps brachii

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Pronation ◦ Pronator quadratus, pronator teres

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Supination ◦ Biceps brachii, supinator muscle

Muscles 

Biceps brachii



◦ Insertion

◦ Insertion

 Tuberosity of the radius

 Styloid process of the raidus

◦ Movement

◦ Movement

 Flexes elbow, supinates forearm

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Brachialis ◦ Insertion  Coronoid process of ulna

◦ Movement  Flexes elbow

Brachioradialis

 Flexes elbow



Triceps brachii ◦ Insertion  Olecranon process of ulna

◦ Movement  Extension

Muscles 

Supinator ◦ Insertion  Proximal end of the lateral surface of the shaft of the radius

◦ Movement

 Supinates the elbow



Pronator teres ◦ Insertion  Middle of the lateral surface of the shaft of the radius

◦ Movement

 Pronates elbow



Anconeus ◦ Insertion  Lateral surface of the olecranon process of the ulna

◦ Movement

 Extends elbow

Joints 

Humeroradial ◦ Articulation of lateral distal humerus and proximal radius

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Radioulnar ◦ Articulation between radial notich of the proximal lateral aspect of ulna, the radial head and capitulum of distal humerus  Important in supination andpronation

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Humeroulnar ◦ Articulation between distal humerus medially and proximal ulna

Nerves ◦ Median  Passes deep in the cubital fossa medial to the biceps and brachialis

◦ Radial  Lateral to biceps and brachialis

◦ Ulnar  Courses posteriorly in groove between the medial epicondyle and olecranon process

◦ Musclocutaneous  Passes through cubital fossa, supplies the anterior forearm and thenar muscles

Elbow Anatomy 

MISC ◦ Medial & lat. Condyles with the olecranon process form a straight line when arm is straight  Forms a triangle when arm is bent

◦ Posterolateral triangle – radial head, lat. Condyle, olecronon process  Good place for aspiration

Elbow Anatomy 

Carrying angle ◦ 5-15 degrees female 5-10 degrees male  This angle will increase in athletes that have participated in throwing sports for a long time, or the angle could increase if there is a fx

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ROM ◦ Flexion – 145 degrees ◦ Extension – 0 / -5 degrees ◦ Pronation & supination – 90 degrees

Flexion and Extension

Pronation and Supination