The Upper Extremity

Bones, Muscles, Vessels,

pg 608

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!!!

pg 612

Joints of Upper Extremity

Sternoclavicular Synovial-saddle Diarthrosis

Acromioclavicular Synovial-plane Diarthrosis

Glenohumeral joint Synovial-ball&socket Diarthrosis Many ligaments Muscle reinforcement Great Mobility

pg 626-7

Joints of the Upper Extremity

Elbow Joint Synovial – hinge Diarthrosis

Articulations Humerus & Ulna Humerus & Radius

Many Ligaments

pg 681-2

Joints of Upper Extremity

Proximal Radioulnar joint Synovial - pivot Diarthrosis

Distal Radioulnar joint Synovial – pivot Diarthrosis

Allows pronation and supination of forearm

pg 691

Radiocarpal joint Synovial-condyloid Distal radius with proximal row of

carpals Intercarpal joints

Synovial-plane Carpal-metacarpal (2-5)

Synovial-plane Trapezium-metacarpal 1

Synovial-saddle Metacarpal-phalangeal

Synovial-condyloid Interphalangeal

Synovial-hinge ALL DIARTHROSES

Joints of the Upper Extremity Pg 711

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

RotatorCuff

pg 614

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!!

pg 614

Innervation of Muscles Moving Arm

Muscle Innervation

SubscapularisTeres Major

Subscapular N.

InfraspinatusSupraspinatus

Suprascapular N.

Teres Minor Axillary N.

Coracobrachialis Musculocutaneous N.

Arm Muscles

Cross elbow, move forearm 2 compartments

Anterior Flexors of forearm

Posterior Extensors of forearm

pg 667

Arm Muscles

Anterior compartment Brachialis Biceps brachii Coracobrachialis

pg 651

pg 671

Arm Muscles Posterior compartment

Triceps brachii

pg 636

Muscles of ArmMuscle Origin Insertion ActionAnterior

Brachialis Ant shaft , distal humerus Coronoid proc/tuberosity

(ulna)

Flex forearm

Biceps Brachii Long: supraglenoid tubercle (scapula)

Short: coracoid proc (scapula)

Radial Tuberosity (radius)

Flex forearm, Supination

Coracobrachialis Coracoid proc (scapula) Medial surface midshaft (humerus)

Flex arm

PosteriorTriceps Brachii Long: Infraglenoid tubercle

Short: Posterior shaft

(middle humerus)

Lateral: Posterior Shaft

(proximal humerus)

Common tendon to olecranon (ulna)

Extend forearm

Arm Muscle Innervation

Anterior compartment Musculocutaneous nerve

Coracobrachialis Brachialis Biceps brachii

Posterior compartment Radial nerve

Triceps brachii

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

pg 694

Forearm Muscles Anterior flexor compartment

Superficial and Deep Most flexors have common tendon on medial epicondyle Contains 2 pronators

Posterior extensor compartment Superficial and Deep Most extensors in superficial layer have common origin on

lateral epicondyle

pg 688

Anterior Compartment of Forearm

Muscles Nerves Superficial

Flexor digitorum superficialis & brevis Median Flexor carpi radialis Median Pronator teres Median Palmaris longus Median Flexor carpi ulnaris Ulnar

Deep Pronator quadratus Median Flexor pollicis longus Median Flexor digitorum profundus Ulnar (med 1/2)

Median (lat 1/2)

pg 696

Posterior Compartment of Forearm

Muscles Nerves Superficial

Brachioradialis Radial Anconeus Radial Extensor carpi radialis longus & brevis Radial Extensor digitorum Radial Extensor carpi ulnaris Radial Extensor digiti minimi Radial

Deep Supinator Radial Abductor pollicis longus Radial Extensor pollicis longus + brevis Radial Extensor indicus Radial

pg 702

Hand Bones

Carpus (8) “True” wrist Distal to radius/ulna

Metacarpus (5) Distal to carpus

Phalanges (14) Distal to metacarpus

pg 711

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

Interossei Muscles

Lumbrical Muscles

pg 718pg 723

Dorsal Palmar

Blood Supply - Veins Deep veins

Deep palmar venous arches Radial - forearm Ulnar - forearm Brachial – arm/elbow Axillary – axilla Subclavian - neck

Superficial Veins Digital Superficial palmar venous

arches Median – forearm Median cubital – elbow

Blood draws!! Cephalic – arm/forearm Basilic – arm/forearm

pg 677

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

pg 675

Axilla Armpit!! Where axillary hairs grow Boundaries

Ventral Pectoral muscles

Dorsal Latissimus dorsi, teres major,

subscapularis Medial

Serratus ventralis Lateral

Inetrtubercular (Bicipital) groove of humerus

Contents axillary lymph nodes, axillary

vessels, brachial plexus

pg 688

Surface Anatomy of Arm

Cephalic Vein Biceps brachii Triceps brachii Olecrenon

Process Medial Epicondyle Lateral Epicondyle

pg 688

Surface Anatomy of Elbow

Cubital Fossa Anterior surface elbow Contents

Median Cubital Vein Brachial Artery Median Nerve

Boundaries Medial= Pronator teres Lateral= Brachioradialis Superior= Line between epicondyles

pg 686

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)

pg 715

Brachial Plexus

Nerve plexus 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

pg 618

pg 21

Brachial Plexus

Really Tired? Drink Coffee Buddy!

R = RAMI (ventral) (5) T = TRUNKS (3) D = DIVISIONS (2) C = CORDS (3) B = BRANCHES (Many!!)

pg 660

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 AnteriorPosterior

Middle AnteriorPosterior

Lower Anterior Posterior

Divisions Join to form Cords! (in axilla)

Trunks Division Cords

U A LateralP

M A MedialP

L A PosteriorP

Cords Give off Branches!! (in axilla) Lateral Musculocutaneous

Median

Medial Ulnar

Posterior RadialAxillary

(thoracodorsal)

(subscapular)

Brachial Plexus – Cords and Branches

Lateral Musculocutaneous n. Median n.

Medial Ulnar n.

Posterior Radial n. Axillary n. Thoracodorsal n. Subscapular n.

Lateral Cord Musculocutaneous nerve

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 (not part of lateral cord) Runs with suprascapular artery and vein {C5, C6} Innervates

Supraspinatus Infraspinatus

Medial Cord Ulnar nerve

Course: 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 Cord 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 ext. carpi radialis L + B)

Posterior Cord (continued) Axillary 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 Innervates:

Subscapularis, Teres major Thoracodorsal nerve

Course: Runs with thoracodorsal artery and nerve

Innervates: Latissimus dorsi

Cutaneous Innervation to Hand

pg 620, 727, 729

Nerve Damage Ulnar 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

pg 737-8