Posterior Forearm Muscles & Elbow Joint Anatomy PDF

Posterior Aspect of Forearm and Elbow Joint Posterior Aspect of Forearm Posterior forearm muscles: Wrist joint extension Thumb extension Digit extension Forearm supination -‐Superficial and Deep layers -‐Common innervation (Radial nerve) Superficial Layer Brachioradialis O: Lateral supraepicondylar ri...

Posterior Aspect of Forearm and Elbow Joint Posterior Aspect of Forearm Posterior forearm muscles: Wrist joint extension Thumb extension Digit extension Forearm supination -‐Superficial and Deep layers -‐Common innervation (Radial nerve) Superficial Layer Brachioradialis O: Lateral supraepicondylar ridge I: Lateral side of distal radius N: Radial nerve F: Flexion of forearm Superficial Layer Extensor Carpi Radialis Brevis O: Lateral epicondyle I: Base of 2. and 3. Metacarpal N: Radial nerve F: Extension and abduction of hand Superficial Layer Extensor Carpi Radialis Longus O: Lateral supraepicondylar ridge I: Base of 2. Metacarpal N: Radial nerve F: Extension and abduction of hand Superficial Layer Extensor Digitorum O: Lateral epicondyle I: 2-‐3-‐4-‐5 Distal Phalanges dorsal sides N: Radial nerve F: Extension of hand and 2-‐3-‐4-‐5 digits Superficial Layer Extensor Digiti Minimi O: Lateral epicondyle I: Dorsal hood 5. digit N: Radial nerve F: Extension of 5. digit Superficial Layer Extensor Carpi Ulnaris O: Lateral epicondyle, Posterior border of ulna I: Base of 5. metacarpal N: Radial nerve F: Extension and adduction of hand Superficial Layer Anconeus O: Lateral epicondyle I: Olecranon, proximal posterior ulna N: Radial nerve F: Assist triceps in extending elbow joint,stabilizes elbow joint, abducts ulna during pronation and forearm extension Deep Layer Supinator O: Lateral epicondyle, Radial Collateral and Annular lig. Supinator crest of ulna I:Lateral, posterior and anterior surfaces of proximal third of radius N: Radial nerve F: Forearm supination Deep Layer Abductor pollicis longus O: Posterior surface of proximal ulna and radius, interosseous membrane I:Base of 1. metacarpal N: Radial nerve F: Thumb abduction and extension Deep Layer Extensor pollicis brevis O: Distal 1/3 of posterior Radius, I: Proximal phalanx base (Thumb) N: Radial nerve F: MCPJ, CMCJ extension (thumb) Deep Layer Extensor pollicis longus O: Mid 1/3 of posterior Ulna, I: Distal phalanx base (Thumb) N: Radial nerve F: IPJ, MCPJ, CMCJ extension (thumb) Deep Layer Extensor indicis O: Distal 1/3 of posterior Ulna, I: Extensor expansion of 2nd digit N: Radial nerve F: Extension of 2. digit Snuff Box Anteriorly-Abdcutor pollicis longus & ext.pollicis brevis Posteriorly- ext. Pollicis longus Radial a. Scaphoid & trapezium in the floor Historically, tobaccos placed in this depresion before inhaled in to the nose Vessels of post.forearm Arteries: Radial artery : Ulnar artery : -‐Posterior interosseous a. -‐Anterior interosseous a. Veins: Related to arteries Nerves of Posterior Forearm Radial nerve – superficial and deep branches Deep branch of radial nerve passes post.compartment by passing between two head of supinator becomes – posterior interosseous nerve Radial Tunnel - Posterior Interosseous Nerve Compression Syndrome Musculo-aponeurotic tunnel (lateral epicondyle of the humerus -distal edge of the supinator muscle) ELBOW JOINT Humero-‐ulnar and Humero-‐radial articulations Radial collateral lig. Ulnar collatera lig. Annular lig. of Radius Elbow Joint Hinge type Humeroulnar- trochlea of humerus &trochlear notch of ulna Humeroradial- capitulum of humerus & head of radius Proximal radioulnar joint- head of radius & radial notch of ulna *FAT PADS SİGN Ulnar collateral ligament Extends from the medial epicondyle of the humerus to the coronoid process of the ulna. Triangular shape, composed of three parts: anterior, posterior,inferior band. Radial collateral ligament has a low attachment to the lateral epicondyle of the humerus. The distal fibres blend with the annular ligament that encloses the head of the radius, and fibres of the supinator and the extensor carpi radialis brevis muscles. Annular ligament Reinforces the joint by holding the radius and ulna together at their proximal articulation. The quadrate ligament ,maintains constant tension during pronation and supination movements of the forearm. Blood Supply Collateral branches of brachial a. & recurrent branches of ulnar & radial a. Nerve Innervation Musculocutaneous & radial n. Ulnar n. Median n. Ant. interosseous n. Supination and Pronation Tennis Elbow (Lateral epicondylitis) Causes pain overuse or repeated action of the muscles of the forearm Treatments ; rest or activity modification, icing, anti-inflammatory medications, physical therapy, injections of a steroid medication Pulled elbow a common injury among children under the age of five. result of the radius bone becoming partially dislocated Simple supination and compression of elbow J. Thanks for attention