The Upper Extremity Bones, Muscles, Vessels,

Bones 30 bones!!!! Appendicular skeleton Pectoral girdle Glenoid cavity Allows for mobility Attachments Upper extremity: Arm humerus Forearm Radius, ulna (interosseous membrane) Hand Carpals, metacarpals, phalanges Review bones and landmarks studied in lab!!!

Joints of Upper Extremity Sternoclavicular Synovial-saddle Diarthrosis Acromioclavicular Synovial-plane Glenohumeral joint Synovial-ball&socket Many ligaments Muscle reinforcement Great Mobility

Joints of the Upper Extremity Elbow Joint Synovial – hinge Diarthrosis Articulations Humerus & Ulna Humerus & Radius Many Ligaments

Joints of Upper Extremity Proximal Radioulnar joint Synovial - pivot Diarthrosis Distal Radioulnar joint Synovial – pivot Allows pronation and supination of forearm

Joints of the Upper Extremity Radiocarpal joint Synovial-condyloid Distal radius with proximal row of carpals Intercarpal joints Synovial-plane Carpal-metacarpal (2-5) Trapezium-metacarpal 1 Synovial-saddle Metacarpal-phalangeal Interphalangeal Synovial-hinge ALL DIARTHROSES

Review of Naming….. What do the following names TELL you about the muscle? Naming Flexor carpi ulnaris Flexor digitorum superficialis Flexor pollicis longus Pronator quadratus Extensor carpi radialis brevis

Scapula Muscles If the origin is on the scapula – moves the arm Subscapularis Supraspinatus Infraspinatus Teres Minor Teres Major Latissimus Dorsi (partial attachment) Coracobrachialis Rotator Cuff

Scapula Muscles If the insertion is on the scapula – moves the scapula Rhomboids Trapezius Pectoralis Minor Serratus Ventralis Levator Scapulae Use location of Insertion to determine movement!!

Scapula Innervation Origin on scapula Insertion on scapula Subscapularis and teres major Subscapular Supraspinatus and Infraspinatus Suprascapular Teres Minor Axillary Latissimus Dorsi Thoracodorsal Coracobrachialis Musculocutaneous Insertion on scapula Rhomboids and Levator Scapulae Dorsal scapular Trapezius Accessory Pectoralis Minor Medial and Lateral Serratus Ventralis Long thoracic

Arm Muscles Cross elbow, move forearm 2 compartments Anterior Flexors of forearm Posterior Extensors of forearm

Arm Muscles Anterior compartment Brachialis Biceps brachii Coracobrachialis Bracioradialis

Arm Muscles Posterior compartment Triceps brachii Anconeus

Arm Muscle Innervation Anterior compartment Radial nerve Bracioradialis Musculocutaneous nerve Coracobrachialis Brachialis Biceps brachii Posterior compartment Triceps brachii Anconeus

Forearm Muscles Cross elbow, wrist and finger joints Movement of hand and fingers Cross Wrist flex, extend, abduct, adduct hand Cross Fingers flex, extend fingers Proximally are fleshy Distally have long tendons Flexor and extensor retinacula “wristbands” Keep tendons from jumping outwards when tensed

Forearm Muscles Anterior flexor compartment Superficial and Deep Most flexors have common tendon on medial epicondyle Contains 2 pronators Posterior extensor compartment

Anterior Compartment of Forearm Muscles Nerves Superficial Flexor digitorum superficialis Median Flexor carpi radialis Median Pronator teres Median Palmaris longus Median Flexor carpi ulnaris Radial Deep Flexor pollicis longus Median Flexor digitorum profundus Ulnar (med 1/2) Median (lat 1/2)

Anterior Compartment Forearm

Posterior Compartment of Forearm Muscles Nerves Superficial Extensor carpi radialis longus Radial Extensor digitorum Radial Extensor carpi ulnaris Radial Deep Supinator Radial Abductor pollicis longus Radial Extensor pollicis longus + brevis Radial Extensor indicus Radial

Posterior Compartment of Forearm

Hand Bones Carpus (8) Metacarpus (5) Phalanges (14) “True” wrist Distal to radius/ulna Metacarpus (5) Distal to carpus Phalanges (14) Distal to metacarpus

Intrinsic Muscles of the Hand Muscle Nerve Pinky (little finger) All digiti minimi Ulnar (Flexor, Abductor, Opponens) Thumb Abductor pollicis brevis Median Flexor pollicis brevis Median Opponens pollicis Median Adductor pollicis Ulnar Other Intrinsic Muscles Palmar + Dorsal Interossei Ulnar Lumbricals Median, Ulnar

Intrinsic Muscles of the Hand Lumbrical Muscles Interossei Muscles

Blood Supply - Veins Deep veins Superficial Veins Deep palmar venous arches Radial - forearm Ulnar - forearm Brachial – arm/elbow Subclavian - neck Axillary – axilla Superficial Veins Cephalic – arm/forearm Basilic – arm/forearm Median cubital – elbow Blood draws!! Median - forearm Superficial palmar venous arches Digital

Blood Supply - Arteries Subclavian (neck) Axillary (armpit) Subscapular Circumflex humeral arteries Brachial (arm) Deep brachial Radial (forearm) Ulnar (forearm) Common Interosseous Superficial & Deep Palmar arches Digital

Axilla Armpit!! Where axillary hairs grow Boundaries Contents Ventral Pectoral muscles Dorsal Latissimus dorsi, teres major, subscapularis Medial Serratus ventralis Lateral Bicipital groove of humerus Contents Axillary lymph nodes, Axillary vessels, brachial Plexus

Surface Anatomy of Arm Biceps brachii Triceps brachii Olecrenon Process Medial Epicondyle Lateral Epicondyle

Surface Anatomy of Elbow Cephalic vein Cubital Fossa Anterior surface elbow Contents Median Cubital Vein Brachial Artery Median Nerve Boundaries Medial= Pronator teres Lateral= Brachioradialis Superior= Line between epicondyles

Surface Anatomy of Hand Carpal Tunnel Carpals concave anteriorly Carpal ligament covers it Contains: long tendons, Median nerve Inflammation of tendons = compression of Median nerve Anatomical Snuffbox Lateral = E.pollicis brevis Medial = E. pollicis longus Floor = scaphoid, styloid of radius Contains Radial Artery (pulse)

Brachial Plexus Nerve plexus Lies partly in neck and partly in axilla Network of nerves formed by ventral rami Lies partly in neck and partly in axilla Gives rise to almost all nerves that supply upper limb Formed by intermixing of ventral rami of spinal nerves C5-C8 and T1 Small contributions from C4 and T2

Ventral Rami

Really Tired? Drink Coffee Buddy! Brachial Plexus Really Tired? Drink Coffee Buddy! R = RAMI (ventral) (5) T = TRUNKS (3) D = DIVISIONS (2) C = CORDS (3) B = BRANCHES (Many!!)

Rami join to form Trunks! (in neck) Ventral Rami Trunks C5 Upper Trunk C6 C7 Middle Trunk C8 T1 Lower Trunk

Trunks Split to form Divisions! (in neck) Trunks Divisions Upper Anterior Posterior Middle Anterior Posterior Lower Anterior Posterior

Divisions Join to form Cords! (in axilla) Trunks Division Cords U A Lateral P M A Medial L A Posterior

Cords Give off Branches!! (in axilla) Lateral Musculocutaneous Median Medial Ulnar Posterior Radial Axillary (thoracodorsal) (subscapular)

Put it all together……..

Brachial Plexus – Cords and Branches Lateral Musculocutaneous Median Medial Ulnar Posterior Radial Axillary Thoracodorsal Subscapular

Lateral Cord Musculocutaneous nerve Suprascapular Off lateral cord Course: Anterior arm Becomes cutaneous and gives skin sensation to lateral forearm Innervates: Corocobrachialis (motor) Biceps brachii (motor) Brachialis (motor) Skin distal to the elbow (sensory) Suprascapular Runs with suprascapular artery and vein {C5, C6} Innervates Supraspinatus Infraspinatus

Medial Cord Ulnar nerve Course: Innervates: Comes off medial cord Descends along medial side of arm Passes posterior to medial epicondyle Follows the ulna Superficial to carpal tunnel into hand Branches to supply intrinsics and skin Innervates: Flexor carpi ulnaris (motor) Flexor digitorum profundus (motor) Most intrinsic hand muscles (motor) Dorsal branch supplies skin of medial 2/3 of hand (sensory)

Both Medial and Lateral Cords Median nerve Course: Middle of brachial plexus (from lateral and medial cords) Does not branch in arm Distal to elbow provides many branches to most forearm flexors Passes through carpal tunnel to hand to lateral palmar intrinsics Innervates: Anterior forearm (motor) Most flexors, some intrinsics (thumb) 2/3 Lateral palm (sensory) Dorsum of fingers 2 and 3 (sensory)

Posterior Cords Radial nerve Largest branch of brachial plexus Comes from posterior cord Course: Through arm Around humerus Around lateral epicondyle (then divides) Innervates: Posterior muscles of arm and forearm Triceps brachii, anconeus, supinator, brachioradialis Divides in forearm: Superficial Skin of arm and dorsolateral surface of hand Deep Extensor muscles of forearm (eg E. carpi radialis L + B)

Posterior Cord Axillary nerve Subscapular nerve Thoracodorsal nerve Branches off posterior cord Course: Runs posterior to humerus Runs with caudal humeral circumflex artery Innervates: Deltoid and teres minor (motor) Capsule of shoulder, skin of shoulder (sensory) Subscapular nerve Subscaplaris, Teres major Thoracodorsal nerve Runs with thoracodorsal artery and nerve Latissimus dorsi

Cutaneous Innervation to Hand

Nerve Damage Ulnar nerve Median nerve Radial nerve “Claw hand” Inability to extend fingers at interphalangeal joints, results in permanent flexion = claw Median nerve “Ape hand” Inability to oppose thumb Radial nerve “Wrist drop” Inability to extend the hand, inability to fully extend forearm