MSS Of The Elbow, Forearm & Wrist PDF

MD1020 MSS Lecture Week 8 MSS of the Elbow, Forearm & Wrist A/Prof Kate Domett [email protected] Questions to “Piazza” Learning Outcomes: Upper Limb 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Describe and demonstrate the main anatomical landmarks of the clavicle, scapula, humerus, radius and ulna. Iden...

MD1020 MSS Lecture Week 8 MSS of the Elbow, Forearm & Wrist A/Prof Kate Domett [email protected] Questions to “Piazza” Learning Outcomes: Upper Limb 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Describe and demonstrate the main anatomical landmarks of the clavicle, scapula, humerus, radius and ulna. Identify the bones of the wrist and hand and their relative positions. Describe the neurovascular structures lying in close relation to the bones and joints of the upper limb which are at risk of injury following fracture or dislocation. Predict what the functional effects of such injury might be. Briefly describe the origin and distribution of the major arteries and veins and their branches that supply the upper limb (see list of vessels in GLS workbook). Demonstrate the sites at which pulses of the brachial and radial arteries are located. Describe the anatomy of the brachial plexus from its origin in the neck to its terminal branches. Recognise some brachial plexus injuries and explain their clinical presentation. Describe the origin, course and function of the axillary, radial, musculocutaneous, median and ulnar nerves in the upper limb Name the major muscles and muscle groups that the axillary, radial, musculocutaneous, median and ulnar nerves supply together with their sensory distribution. Predict the consequences of injury to these nerves and describe how to test their functional integrity. Describe the anatomical basis of assessment of the cutaneous sensation in the dermatomes of the upper limb Briefly describe the fascial compartments enclosing the major muscle groups of the upper limb; explain the functional importance of those compartments and their contents Interpret standard diagnostic images, e.g. X-ray, MRI, CT of the upper limb to recognize major anatomical bones and bony landmarks in normal anatomy. Learning Outcomes: Week 8 1. 2. 3. 4. 5. Describe the anatomy of the elbow joint. Demonstrate and explain the movements of flexion and extension at the elbow joint. Identify the muscles responsible for these movements. Name the main attachments and nerve supply of these muscles. Describe the anatomy of the radio-ulnar joints. Explain the movements of supination and pronation and identify the muscles responsible for these movements. Name the main attachments and nerve supply of these muscles Describe the anatomy of the wrist. Explain and demonstrate the movements of the wrist joint and name and identify the muscles responsible for these movements. Name the main attachments and nerve supply of these muscles. Describe the boundaries and contents of the cubital fossa Describe the relative positions of the tendons, vessels and nerves in the region of the wrist in relation to injuries. Bones and joints of the upper limb Humerus Elbow (humeroulnar + humeroradial) Radius (lateral) Ulna (medial) (proximal and distal radioulnar joints) Wrist (radio-carpal) Posterior view © Abrahams et al 2003 Elbow THe way they fit is a number of places there is joining, trochlear of distal humerus and trochlear nothc of ulnar •Humerus, ulna, radius • Humeroulnar and humeroradial (and proximal radio-ulnar joint) •Hinge joint • flexion and extension • uniaxial trochlear ulnar radial notch articulating with Anterior view medial epicondyle more prominent then medial reason medial is bigger is because it has an origin of lots of the forearm FLEXOR muscles which are much more strong than the muscles for extension on lateral epicondyle Elbow Joint Coronoid fossa Lateral epicondyle Olecranon fossa Medial epicondyle Radial fossa Trochlear Capitulum Coronoid process Olecranon process hinge-> fledxion and extension humeral radial jointball and socket structure but acts as a hinge joint Anterior view Posterior view Elbow Joint 1 articular capsule and has multiple ligaments collateral towrds the edge Radial collateral ligament Articular capsule Ulnar collateral ligament Annular ligament wrapping around the head of the radius but still allows the radial head to pivot. Ulnar doesn't move and it locked in with olecrannon fossa. Needs to rotate -> wraps around and allows for spinning. 7 Elbow flexion •Brachialis & Biceps brachii • Anterior compartment of arm • Musculocutaneous nerve •Brachioradialis deep to biceps brachii, stronger • Posterior compartment of forearm • Radial nerve inserts into the ulna truberosity-> high yield for what its function is comes from brachium humerus -> proximal to styloid process. Biceps Brachii Long head of biceps brachii from supraglenoid tubercle Short head of biceps brachii from coracoid process Biceps tendon to radial tuberosity Bicipital aponeurosis Anterior view Coracobrachialis Brachialis Brachialis insertion onto ulnar tuberosity Anterior view Anterior view posterior functionally it crosses elbow joint anteriorly to help with flexion of the elbow. Brachioradialis - Lateral supracondylar to lateral distal radius - Posterior compartment of forearm - Radial nerve - Elbow flexor (accessory; in midpronation) 11 Why brachioradialis is an elbow flexor. View of cross section Anterior Anterior compartment of forearm Medial Lateral Posterior compartment of forearm Posterior Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Elbow Extension • Posterior compartment (arm/brachium) • Triceps brachii • Radial nerve high yield only elbow extensor we need to know crosses shoulder joint-> olecranon process of ulna Long head (crosses gleno-humeral jt) Lateral head Medial head Posterior view Radio-ulnar joints •Proximal and distal •Annular ligament of radius •Synovial pivot joints •Pronation (median n.) •Supination (radial n. & musculocutaneous n.) where pronation and supination occur Pivoting of your forearm Distal radioulnar jt Proximal radioulnar jt Axis of rotatory mvt Annular ligament Proximal radioulnar joint Radius Distal radioulnar joint Ulna Radius Ulna ulna sits medial in anatomical position radius sits laterally -> in anatomical position Pronation Supination Anterior view Anterior view Supination Pronation •Supination • Supinator (radial nerve) • Biceps brachii (musculocutaneous nerve) •Pronation (median nerve) • Pronator teres • Pronator quadratus Anterior view 16 17 Wrist •Condyloid joint •Flexion, extension, abduction, adduction, circumduction Articular disc of ulna fibrocartilaginous disc wrist here is articulating with 2 caprals, scaphoid and the lunate Triquetrum synoival capsule Lunate Radius Scaphoid Wrist: radiocarpal joint Ulnar articular disc Adduction Wrist Movements Flexion Abduction Circumduction Extension Wrist Movement towards midline in anatomical position Radial Styloid Process Muscles that move the wrist •Flexion • Flexor carpi radialis + flexor carpi ulnaris •Extension • Extensor carpi radialis longus & brevis + extensor carpi ulnaris •Abduction (or radial deviation) • Abductor pollicis longus, flexor carpi radialis, extensor carpi radialis longus and brevis •Adduction (or ulnar deviation) • Extensor carpi ulnaris and flexor carpi ulnaris Forearm anterior compartment: Flexors of wrist and digits & Pronators Ulnar & Median nerves Anterior Anterior compartment of forearm Medial Lateral Posterior Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Common flexor origin (medial epicondyle) Anterior compartment: Superficial Pronator teres Flexor carpi radialis Origin: distal part of the lateral supraepicondylar • Flexors of wrist • Pronators of forearm Insertion: dorsal surface of base of metacarpal II Innervation: radial nerve Palmaris longus Origin: medial epicondyle of humerus Insertion: palmar aponeurosis of hand Innervation: median nerve Function: flexes the wrist joint, because the palmar aponeurosis anchors skin of the han Anterior view Median nerve Flexor carpi ulnaris Origin: Medial epicondyle of humerus Insertion: base of metacarpals 2 and 3 Innervation: median nerve Function: flexes and abducts the wrist Ulnar nerve Palmaris longus •C. 14% of people do not have palmaris longus in one or both anterior forarms •It was useful to our ancestors who swung from tree to tree is not found in some people. 25 Common flexor origin (medial epicondyle) Anterior compartment: Intermediate Flexor digitorum superficialis • Flexors of digits Median nerve Ulnar nerve and artery Anterior view Anterior compartment: Deep Flexor digitorum profundus • Flexors of digits • Pronators of forearm Flexor pollicis longus really deep, not as deep as pronator pollicis means thumb and a long tendon which flexes the thumb Anterior view Common flexor origin (medial epicondyle) Ulnar nerve Pronator quadratus Posterior compartment of the forearm: Extensors of wrist and digits & Supinator Radial nerve View of cross section Anterior Medial Lateral Posterior compartment of forearm Posterior Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Posterior compartment: Superficial Origin: distal part of the lateral supraepicondylar Insertion: dorsal surface of base of metacarpal II Innervation: radial nerve • Extensors of wrist and digits Ext carpi radialis longus *Ext carpi radialis brevis Origin: lateral epicondyle of humerus Insertion: dorsal surface of base of metacarpals II and III Innervation: deep branch of radial nerve *Ext digitorum Origin: lateral epicondyle of humerus Insertion: 4 tendons which insert into dorsal aspects of the bases of middle and distal phalanges Innervation: posterior interosseous nerve Posterior view Common extensor origin (lateral epicondyle) *Ext digitorum minimi *Ext carpi ulnaris Posterior compartment: Deep Supinator 3 muscles which help move our thumb-> we have 2 extensors of our thumb in posterior and an abductor • Extensors of wrist and digits • Supinators • Thumb abductor Posterior view Ext pollicis longus Common extensor origin (lateral epicondyle) Ext pollicis brevis joint of thumb joint of thumb Ext indicis index finger Abductor pollicis longus Posterior compartment: Deep APL EPL EPB EPB EPL APL Posterior view Flexion & Extension of the wrist FCU Anterior view ECRL/B FCR ECU Lateral view Posterior view 32 Abduction & Adduction of the wrist Anterior view Posterior view • Abduction (lateral ms) - Flexor carpi radialis and extensor carpi radialis (longus and brevis) lateral muscles-> flexor capal radials • Adduction (medial ms) • Flexor carpi ulnaris and extensor carpi ulnaris 33 Abduction & Adduction of the wrist FCR Lateral view ECRL/B ECU FCU Posteriomedial view 34 carpal tunnel syndrome-> want to look at the anatomy 35