1. The Upper Extremity Arm Muscles, Axilla, Brachial Plexus

2. Bones of Upper Extremity §Appendicular Skeleton §Pectoral Girdle = scapula,clavicle §Upperlimb l Arm: humerus l Forearm: radius, ulna Interosseus membrane l Hand: carpals, metacarpals, phalanges §Review Bones + Landmarks studied in Lab!!

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

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

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

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

7. Review of Naming §Naming l Flexor carpi ulnaris l Flexor digitorum superficialis l Flexor pollicis longus l Pronator quadratus l Extensor carpi radialis brevis Refer to tables in chapter 11 of text for muscle O + I (Table 11.8-11.13) Know at least 1 action of every muscle What do the following names TELL you about the muscle?

8. Muscles of Scapula §If ORIGIN on scapula = Move Arm l Subscapularis l Supraspinatus l Infraspinatus l Teres Minor l Teres Major l Latissimus Dorsi (partial O on scap) l Coracobrachialis §If INSERTION on scapula = Move scapula l Rhomboids l Trapezius l Pectoralis Minor l Serratus Ventralis l Levator Scapulae pg 283 Rotator Cuff Use location of Insertion to determine movement!!

9. Innervation of Scapula Muscles §Origin on Scapula: l Latissimus dorsi = Thoracodorsal nerve l Subscapularis, Teres Major = Subscapular nerves l Supraspinatus, Infraspinatus = Suprascapular nerves l Teres Minor = Axillary nerve §Insertion on Scapula l Levator Scapular, Rhomboids = Dorsal Scapular nerve l Pectoralis Minor = Pectoral n. l Serratus Ventralis = Long Thoracic n. l Trapezius = Accessory n. Refer to tables in chapter 11 of text for muscle O + I Know at least 1 action of every muscle

10. Muscles of Arm: Cross elbow, Move forearm §2 Compartments l Anterior: Flexors of forearm l Posterior: Extensors of forearm §Anterior Compartment l Biceps brachii = MC nerve l Brachialis = MC nerve l Brachioradialis = Radial nerve §Coracobrachialis = MC nerve l O = coracoid process of scapula l I = medial side humeral shaft l A = flex, adduct arm §Posterior Compartment l Triceps brachii = Radial nerve l Anconeus = Radial nerve MC = musculocutaneous nerve

11. Muscles of forearm: Cross wrist + finger joints, moves hand §Cross Wrist = flex, extend, abduct, adduct hand §Cross Fingers = flex, extend fingers §Most muscles fleshy proximally, long tendons distally §Flexor + Extensor Retinacula l wristbands keep tendons from bowing l thick, deep fascia §Anterior Flexor Compartment ( Superficial + Deep layers ) l Most flexors have common tendon on medial epicondyle l Contains 2 pronators l Innervated by *Median, Ulna nerves §Posterior Extensor Compartment (Superficial + Deep layers) l Innervated by Radial nerve (or branches of)

12. Innervation of Anterior Compartment-Forearm Muscles §Superficial Muscles l Flexor digitorum superficialisMedian l Flexor carpi radialisMedian l Pronator teresMedian l Palmaris longusMedian l Flexor carpi ulnarisUlnar §Deep Muscles l Pronator quadratusMedian l Flexor pollicis longusMedian l Flexor digitorum profundusUlnar (med 1/2) Median (lat 1/2) MuscleNerve

13. Anterior Compartment Forearm Flexor Carpi Radialis Flexor Retinaculum Medial Epicondyle Flexor Digitorum Superficialis is deep to other flexors pg 302 Flexor Carpi Ulnaris Brachioradialis Pronator Teres Anterior View

14. Innervation of Posterior Compartment-Forearm Muscles §Superficial l Extensor carpi radialis longusRadial l Extensor digitorumRadial l Extensor carpi ulnarisRadial §Deep l SupinatorRadial l Abductor pollicis longus Radial l Extensor pollicis longus + brevis Radial l Extensor indicus Radial Muscle Nerve

15. Posterior Compartment of Forearm Extensor digitorum Extensor carpi ulnaris Ext Carpi Radialis Longus Brachioradialis Lateral Epicondyle Posterior View

16. Intrinsic Muscles of Hand §Pinky (little finger) l All digiti minimiUlnar (Flexor, Abductor, Opponens) §Thumb l Abductor pollicis brevisMedian l Flexor pollicis brevisMedian l Opponens pollicisMedian l Adductor pollicisUlnar §Other Intrinsic Muscles l Palmar + Dorsal InterosseiUlnar l LumbricalsMedian, Ulnar MuscleNerve

17. Intrinsic Muscles of Hand pg 297 ABduction Palmar Interossei Lumbricals ADDuction 1st 2nd 3rd 4th Dorsal Interossei Interossei help the lumbricals to extend IP joints and flex MC-P joints

18. Blood Supply: Veins pg 547 Cephalic (arm-forearm) Basilic (arm-forearm) Median Cubital (elbow) Median Vein SF. Palmar Venous Arch Digital SUPERFICIAL Subclavian (neck) Axillary (axilla) Brachial (arm-elbow) Radial (forearm) Ulnar (forearm) Deep Palmous Venous arch DEEP

19. Blood Supply: Arteries §Subclavian (neck) §Axillary (armpit) l Subscapular §Brachial (arm) l Deep brachial §Radial (forearm) §Ulnar (forearm) l Common Interosseous §Superficial & Deep Palmar arches l Digital Pg 536

20. Axilla = Armpit §Region between arm and chest §Boundaries l Ventral - pectoral muscles l Dorsal = latissimus dorsi, teres major subscapularis l Medial = serratus ventralis l Lateral = bicipital groove of humerus §Contents l Axillary lymph nodes, Axillary vessels Brachial Plexus

21. Surface Anatomy of Upper Limb §Biceps + Triceps brachii §Olecrenon Process §Medial Epicondyle §Cubital Fossa l Anterior surface elbow l Contents Median Cubital Vein Brachial Artery Median Nerve l Boundaries Medial= Pronator teres Lateral= Brachioradialis Superior= Line between epicondyles pg 748

22. Surface Anatomy of Upper Limb §Carpal Tunnel l Carpals concave anteriorly l Carpal ligament covers it l Contains: long tendons, Median nerve l Inflammation of tendons = compression of Median nerve §Anatomical Snuffbox l Lateral = E. pollicis brevis l Medial = E. pollicis longus l Floor = scaphoid, styloid of radius l Contains Radial Artery (pulse) pg 749

23. Brachial Plexus § Network of nerves; part in neck, part in axilla § Muscles of upper limb receive innervation from nerves of the brachial plexus §Formed from Ventral Rami of Inferior 4 Cervical Nerves (C 5-8 ) and T 1

24. Where Ventral Rami Come From Dorsal Root Ventral Root spinal nerve Dorsal Ramus of spinal nerve Ventral Ramus of spinal nerve Pg 381

25. Parts of Brachial Plexus § R eally T ired? D rink C offee B uddy! §R = ROOTS (ventral rami) §T = TRUNKS §D = DIVISIONS §C = CORDS §B = BRANCHES

26. Roots join to form Trunks! (in neck) §Ventral Rami Trunks §C5Upper Trunk §C6 §C7 Middle Trunk §C8 §T1 Lower Trunk

27. Trunks Split to form Divisions! (in neck) § Trunks Divisions §UpperAnterior Posterior §MiddleAnterior Posterior §LowerAnterior Posterior

28. Divisions Join to form Cords! (in axilla) U A P M A P L A P POSTERIOR CORD LATERAL CORD MEDIAL CORD TrunksDivisions Cords

29. Cords Give off Branches!! (in axilla) §Lateral Musculocutaneous Median §MedialUlnar §PosteriorRadial Axillary (thoracodorsal) (subscapular)

30. PUT IT ALL TOGETHER…... pg 416 Learn Figure 14.11c in textbook!

31. Innervation by Posterior Cord §Radial Nerve (largest branch) l Course: Through arm, around humerus, around lateral epicondyle, then divides l Innervates: all posterior muscles of arm and forearm Triceps brachii, anconeus, supinator, brachioradialis l Divides in forearm: Superficial = skin of arm and dorsolateral surface of hand Deep = extensor muscles of forearm (eg E. carpi radialis L + B) l Damage to Radial Nerve = wristdrop Inability to extend the hand, st inability to fully extend forearm

32. Innervation by Posterior Cord (continued) §Axillary Nerve (runs w/ caudal humeral circumflex a.) l Innervates: Deltoid and Teres minor (motor inn) Capsule of shoulder, skin of shoulder (sensory inn) §Subscapular Nerve {branches of C5 + C6 rami} l Innervates: Subscapularis, Teres major §Thoracodorsal Nerve (runs w/thoracodorsal a+v) l Innervates: Latissimus dorsi

33. Innervation by Lateral Cord §Musculocutaneous l Course: branches to arm, distal to elbow becomes cutaneous for lateral forearm skin l Innervates Biceps brachii, brachialis, coracobrachialis (motor inn) Skin distal to elbow (sensory) §Suprascapular (runs w/suprascapular a+v) {C5, C6} l Innervates: Supraspinatus, Infraspinatus

34. Innervation by both Lateral and Medial Cords §Median l Course: middle of brachial plexus, 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 l Innervates: most muscles of anterior forearm (motor inn) (eg) most flexors, some intrinsics (thumb) l Innervates: skin of lateral 2/3 hand on palm side, dorsum of fingers 2+3 (sensory inn) l Nerve Damage = “Ape” Hand Inability to Oppose Thumb

35. Innervation by Medial Cord § Ulnar l Course: runs along medial side of arm, behind medial epicondyle, superficial to carpal tunnel into hand, branches to supply intrinsics and skin l Innervates: FCU and part of FDP, most intrinsics (motor inn) Skin of medial 2/3 of hand A+P (sensory inn) l Nerve Damage: Clawhand Inability to extend fingers at interphalangeal joints, results in permanent flexion = claw

36. Cutaneous Innervation to the Hand

37. Ulnar Nerve Brachial Artery Median Nerve Ulnar Nerve Median Nerve Radial Artery Musculocutaneous NerveUlnarArtery Where’s Radial Nerve?