gross- upper limb (osce I) Flashcards

Question

bony landmarks of the **upper end** of the humerus

Answer 1

- head: articulates with the glenoid cavity of the scapula to form the shoulder joint - **anatomical neck**: imaginary line that support head from the rest of the upper end - 2 tubercles: **greater tubercle** (on the lateral lip of bicipital groove) and **lesser tubercle** (on the medial lip, also is smaller) - groove b/w the 2 tubercles is called the **bicipital groove** (*bc biceps tendon passes through it*) or **intertubercular sulcus** - **surgical neck**: imaginary line separating the upper end of humerus from the shaft

Answer 2

has 3 borders & 3 surfaces BORDERS: 1. **Anterior border**: follow the lateral lip of bicipital groove down (the greater tubercle) 2. **Medial border**: start from the medial epicondyle (the fatter one) and go up to the middle of the bicipital groove (it rotates its way around) 3. **Lateral border**: prominent only from the bottom, start from bottom (lateral epicondyle) and go up until you lose it SURFACES: 1. **Anteromedial surface**: b/w anterior & lateral borders (marked by **V shaped deltoid tuberosity**) 2. **Anterolateral surface**: kind of all throughout the bicipital groove but rotates as it goes down 3. **Posterior surface**: middle one-third is crossed by the **radial groove** (*which carries the radial nerve as well*)

Answer 3

1. **Long head** originates from the supraglenoid tubercle of scapula 2. **Short head** originates from the **coracoid process** of the scapula 3. The long head exits shoulder joint, passes through the **bicipital groove**, and is held in place by the **transverse humeral ligament**. 4. Both heads merge into the biceps belly in the upper arm. 5. The biceps tendon inserts into the **radial tuberosity** (main insertion and is on the radial bone) and extends as the **bicipital aponeurosis** (*sheet-like structure that blends with the deep fascia of the forearm, helping protect underlying structures like arteries and nerves*) It is innervated (supplied w nerves) by the **musculocutaneous nerve** (C5-C7, which comes from brachial plexus).

Answer 4

- **medial & lateral epicondyle**: medial is a bit rounded and fatter while lateral is more flatter and inwards - **medial & lateral supracondylar ridge**: parts directly above the epicondyles for both, respectively - **trochlea**: on the medial side, pulley-shaped structure (has the little line in the middle and longer than capitulum)- *only on anterior side* - **capitulum**: on the lateral side, rounded, ball-like structure (*only on anterior side*) - **coronoid fossa**: the hole right above the trochlea - **radial fossa**: hole right above the capitulum - **olecranon fossa**: the big hole on the back (posterior side)

Answer 5

**SITS Muscles (rotator cuff)**: - **Supraspinatus** (originates from scapula) → inserts at uppermost impression on *greater tubercle* - **Infraspinatus** (originates from scapula) → inserts on middle impression on greater tubercle - **Teres Minor** (originates from scapula) → inserts on lower impression on greater tubercle - **Subscapularis** (originates from scapula) → inserts on *lesser tubercle* *Lady b/w 2 majors*: - **Pectoralis Major** → Inserts on the lateral lip of bicipital groove - **Latissimus Dorsi** → Inserts in the bicipital groove - **Teres Major** → Inserts on the medial lip of bicipital groove

Answer 6

**deltoid** → inserts at the deltoid tuberosity (*V ridge*) **medial head of triceps** → originate from radial groove **coracobrachialis** → inserts at the middle of the medial border (*this one is coming from up- from the coracoid process and then goes down to insert into the middle of the humerus*) **brachialis** → originates from lower half of anteromedial & anterolateral surfaces (*this one kinda starts from the middle of the shaft and then goes down*)

Answer 7

**Lateral Cord** → formed by anterior divisions of the upper and middle trunks (C5-C7) **Medial Cord** → formed by anterior division of the lower trunk (C8-T1) **Posterior Cord** → formed by posterior divisions of all three trunks (upper, middle, and lower)

Answer 8

**brachioradialis** → originates from the upper 2/3 of the lateral supracondylar ridge **flexors** → forearm flexor muscles originate from the *medial epicondyle* **extensors** → forearm extensor muscles originate from the *lateral epicondyle* lateral head of **triceps** originates from the upper posterior surface- above the radial groove (*but this should be in shaft idk why its here*)

Answer 9

**vertically**: on the chest wall, extends from 2nd to 6th rib **horizontally**: extends from sternum (midline of the chest) to axilla (armpit region)

Answer 10

- **nipple**: raised, pigmented projection in the center of the breast, contains *15-20 lactiferous duct openings* that allow milk to exit during breastfeeding - **areola**: circular pigmented area surrounding the nipple - contains **montgomery glands (areolar glands)** that produce an oily secretion to prevent the nipples from getting cracked & work as anti-infect ants **axillary tail (tail of spence)**: only part that lies deep in the fascia (*pierces deep fascia at lower border of pectoralis major*) small portion of breast tissue that extends into the armpit

Answer 11

**atrophy of breasts starts** with aging, suspensory ligaments stretch, leading to breast sagging (ptosis). thinner skin and less elasticity

Answer 12

- present in **superficial fascia** right below the skin, and sits on the **pectoralis major** same in males and immature females - modified sweat gland, is an **accessory gland** b/c not essential for survival but has a special function - like other glands, connective tissue & duct system is present - compound tubuloacinar (**compound**: gland has multiple branches, **tubuloacinar**: has both tube-like [ducts] & sac-like [alveoli that produce milk] structures)

Answer 13

increase in **deposition of fat** - estrogen increases = fat tissue accumulates in breast - the actual milk producing glands stay small until a woman gets *pregnant or starts breastfeeding*

Answer 14

*alveoli → lobules → lobes* - **lobes**: 15-20 lobes arranged in a radial pattern (like flower petals) - **lobules**: inside the lobes, smaller compartments that contain the actual *milk-producing glands* - **alveoli**: inside lobules, small-grape like clusters of milk-secreting epithelial cells - surrounded by *myoepithelial cells* that contract under influence of oxytocin to push milk out

Answer 15

axillary nerve and posterior circumflex humeral vessels emerge through this space to reach their terminal destinations in the shoulder **quadrangular space**: bounded: *above*→ subscapularis & teres minor muscles, capsule of the shoulder joint *below* → teres major muscle *medially* → long head of triceps *laterally* → surgical neck of humerus

Answer 16

keep infections localized and prevent them from spreading to other lobes in the breast (they separate the different lobes)

Answer 17

**lactiferous ducts**: smaller branched ducts from the lobules that merge to form a larger lactiferous duct for each lobe and carry milk to the nipple near the nipple, this duct widens to form the **lactiferous sinus (ampulla)** that store milk temporarily before it exists through the nipple *each lobe has 1 lactiferous duct, but multiple lobules*

Answer 18

**fibrous septa (suspensory/cooper's ligaments)**: separate lobules, space between the lobules, bands of connective tissue that extend from deep fascia of pectoralis major to skin of breast - provide structural support (*more dense in upper part of breast & less dense in lower part*) **retromammary space**: thin layer of loose connective tissue and fat located b/w breast and pectoralis major - allows some movement of breast over chest **adipose tissue**: fat that surrounds and fills up most of breast

Answer 19

1. influence of estrogen causes **lactiferous ducts** to grow rapidly and form more branches 2. **development of alveoli & glandular tissue**: connective tissue (CT) spaces replaced with growing alveoli 3. **increased blood supply (vascularity)**: breast becomes highly vascularized to support milk production/gland growth - *veins are also more visible on the surface of breast* 4. **enlargement/darkening of areola**: darker pigment helps newborns locate the nipple **colostrum (first milk)**: thick yellowish fluid produced in late pregnancy, first few days after birth before mature milk comes in

Answer 20

alveoli and ducts gradually **atrophy** (shrink back) - glandular tissue is replaced by fat apoptosis of milk producing cells **lactiferous ducts** remain but become smaller & less active

Answer 21

1. **Internal Thoracic Artery (Internal Mammary Artery)**: branch of the subclavian artery, runs down inner chest (parallel to sternum) 🔹 provides most of the blood supply to the **medial half of the breast** 2. **Lateral Thoracic Artery**: branch of the axillary artery, runs along outer (lateral) chest wall. 🔹 supplies **lateral half of the breast**, especially the glandular tissue 3. **Thoracoacromial Artery (Pectoral Branch)**: branch of the axillary artery, passes over the pectoralis minor muscle. 🔹 provides additional blood supply to the **upper breast** and overlying skin 4. **Posterior Intercostal Arteries**: runs b/w the ribs, supplying the chest wall. 🔹 supports **deep parts of the breast**, especially the lateral and lower portions

Answer 22

4 quadrants→ upper lateral, lower lateral, upper medial, lower medial lateral quadrants: drain into the **anterior axillary (pectoral) nodes** - *75% of lymph from the breast drain here* - located near lower border of pectorals major medial quadrants: drain into the **internal thoracic (parasternal) nodes** (which run alongside internal thoracic artery, parallel to sternum) - in the middle of the chest - *about 20%* - important b/c this is **how cancer spreads** to the other breast!! (b/c of this lil communication space b.w the 2) posterior intercostal arteries: some lymph vessels follow this path to drain into **posterior intercostal lymph nodes** (near the vertebrae) - about 5% - can cause cancer to spread to spine or lungs **from axillary tail**: lymph from axillary tail drains into **posterior axillary (subscapular) subgroup** of lymph nodes - located along posterior axillary fold and are important in *spread of cancer to back & shoulder region*

Answer 23

60% of breast cancers occur in the **upper lateral quadrant** since these are the ones that drain mostly in the axillary node - lymphatic spread to opposite breast, abdominal cavity, or into root of neck is bc of obstruction of normal lymphatic drainage pathways

Answer 24

**low-dose X-ray** used to detect early signs of breast cancer before they can be felt - dangers are minimal and examination can be repeated often

Answer 25

essential for detecting early signs of breast cancer, cysts, or infections 1. inspect breasts for symmetry (some degree of asymmetry is common) 2. any swelling should be noted 3. examine nipples for evidence of retraction (carcinoma can cause retraction by pulling on the lactiferous ducts) 4. patient should lie down so that breasts can be palpated against underlying thoracic wall 5. patient should sit up again and raise both arms above head (shows any carcinoma tethered to the skin, suspensory ligaments, or lactiferous ducts)

Answer 26

**pectoralis minor muscle** **3 subregions**: 1. **proximal**: extends from lateral border of 1st rib to upper border of pectoralis minor 2. **deep**: behind the pectoralis minor muscle 3. **distal**: extends from lower border of pectoralis minor to lower border of the teres major

Answer 27

subclavian artery **axillary artery**: begins from lateral border of 1st rib & ends at lower border of teres major muscle, where it continues as the *brachial artery*

Answer 28

protective layer of connective tissue (fascia) that surrounds the **axillary artery and cords of the brachial plexus** as they pass through the axilla - *derived from the prevertebral fascia of the neck*

Answer 29

*extends from lateral border of 1st rib to upper border of pectoralis minor* **anteriorly (in the front)**: pectoralis major and the skin; cephalic vein crosses the artery **posteriorly (in the back)**: long thoracic nerve (* runs down & controls movement of the serratus anterior*) **laterally**: 3 cords of the brachial plexus **medially**: axillary vein (*axillary vein is always medial to the axillary artery*)

Answer 30

*behind the pectoralis minor muscle* **anteriorly**: pectoralis minor, pectoralis major, and the skin **posteriorly**: posterior cord of the brachial plexus, the subscapularis muscle, and the shoulder joint **laterally: lateral cord of the brachial plexus **medially**: medial cord of the brachial plexus and the axillary vein

Answer 31

*extends from lower border of pec minor to lower border of teres major* **anteriorly**: pectoralis major for a short distance; more distally, the medial root of the median nerve crosses the artery **posteriorly**: subscapularis, latissimus dorsi, and teres major; axillary and radial nerves also lie behind the artery **laterally**: coracobrachialis, biceps, and humerus; lateral root of the median nerve and the musculocutaneous nerve also lie on the lateral side **medially**: ulnar nerve, axillary vein, and medial cutaneous nerve of the arm

Answer 32

formed at the lower border of the teres major muscle by union of venae comitantes (*artery going is accompanied by veins on both sides*) of brachial artery & basilica vein *so basically starts where the axillary artery changes its name to brachial artery* (in the axial) and **runs upward** toward the heart - once it reaches the lateral border of the first rib, changes its name to **subclavian vein** also lies **outside the axillary sheath**

Answer 33

6 branches formed 1 from first part 2 from 2nd part 3 from 3rd part *however, branching pattern is subject to much variation*

Answer 34

**First part**: - Superior thoracic (Highest thoracic) **Second part**: - Lateral thoracic - Thoracoacromial artery **Third part**: - Subscapular artery → divides into circumflex scapular & thoracodorsal arteries - Anterior circumflex humeral - Posterior circumflex humeral

Answer 35

**highest thoracic artery** runs along upper border of pec minor to reach area of the 1st 2 ribs

Answer 36

**thoracoacromial artery**→ short trunk that immediately divides into 4 terminal branches that supply pectoral muscles & acromioclavicular region **lateral thoracic artery** → runs along lower (lateral) border of pectoralis minor along the lateral chest wall

Answer 37

**subscapular artery** large vessel, descends along lower (axillary) border of scapula - divides into **circumflex scapular**and **thoracodorsal arteries** - *circumflex scapular artery curls around axillary border of the scapula to reach the infraspinous fossa* - *thoracodorsal artery descends along the latissimus dorsi muscle to reach the lateral thoracic wall* **anterior and posterior circumflex humeral arteries** → wind around front and back of the surgical neck of the humerus, respectively, and form an anastomosing circle - *posterior artery is the larger of the two and passes through the quadrangular space with the axillary nerve to reach the scapular region*

Answer 38

**arterial anastomosis**: network of blood vessels that connect w/ each other to ensure continuous blood supply, even if one artery gets blocked or damaged in shoulder joint, exists b/w **branches of subclavian artery & axillary artery** **importance**: If the axillary artery is blocked due to injury or compression, blood can still reach the shoulder and upper limb through these alternate routes, preventing tissue damage from lack of blood supply

Answer 39

1. anterior (pectoral) lymph nodes 2. posterior (subscapular) group 3. lateral group 4. central group 5. apical group 6. infraclavicular (deltopectoral) group **peripheral groups** (anterior, posterior, lateral) drain into → **central group** which drains into → **apical group** which drains into → **subclavian lymph trunk** which then enters → **venous circulation**

Answer 40

**location**: lie deep to the pectoralis major muscle, along the lower border of the pectoralis minor (*basically like outside edge of 4th rib*) **drainage**: receive lymph from: - lateral quadrant of the breast - anterolateral abdominal wall above the umbilicus (belly button)

Answer 41

**location**: lie in front of the subscapularis muscle **drainage**: receive lymph from the back, specifically from areas above the iliac crest (lower back region)

Answer 42

**location**: found along the medial side of the axillary vein (*near the head of the humerus*) **drainage**: receive most of the lymph from the upper limb (*q: which receives drainage from upper limb? a: lateral group*)

Answer 43

**location**: situated in the center of the axilla, in the axillary fat deep to the pectoralis minor (*kind of just right in the middle of the armpit*) **drainage**: collect lymph from the three groups above (anterior, posterior, and lateral lymph nodes)

Answer 44

**location**: found at the apex (*top*) of the axilla, near the lateral border of the first rib **drainage**: receive lymph from all other axillary lymph nodes and eventually drain into the subclavian lymph trunk, which then connects to the venous system

Answer 45

*not strictly axillary b/c located outside the axilla* **location**: found in the deltopectoral groove, between the pectoralis major and deltoid muscles **drainage**: receive superficial lymph from the lateral side of the hand, forearm, and arm

Answer 46

axillary artery is **highly vulnerable to trauma**, second only to the popliteal artery (behind the knee) **reason**: located superficially in the axilla, making it prone to lacerations (cuts) due to penetrating injuries, fractures, or gunshot wounds **clinical consequences**: severe bleeding & potential loss of upper limb circulation

Answer 47

**joint** = where 2 bones meet **synovial joint**: joint that has fluid-filled cavity (synovial fluid), allowing smooth movement **plane joint**: joint where flat surfaces slide against each other **double plane**: means there are 2 flat surfaces, allowing movement in two planes (e.g., forward-backward and up-down) *exs. sternoclavicular & acromioclavicular joints*

Answer 48

**structure**: synovial double plane joint that is formed between the sternum (manubrium) and clavicle (medial end) - *this is the articulation* - contains an **articular disc** (fibrocartilage pad inside joint that helps w/ shock absorption, stability, and smooth movement - kind of like a cushion*) **ligaments** (*for strength & stability*): - **sternoclavicular** ligaments (*prevents excessive forward and backward movement of the clavicle*) - **costoclavicular** ligament (*connects clavicle to first rib, limits elevation of the clavicle, preventing excessive upward movement*) **movement**: - elevation & depression (e.g., shrugging shoulders) - protraction & retraction (e.g., pushing shoulders forward and pulling them back). - rotation (during arm elevation) *anterior: skin + fibers of sternocleidomastoid + pec maj. fibers* *posterior: sternohyoid muscle + brachiocephalic artery, left brachiocephalic vein, left common carotid artery*

Answer 49

**structure**: synovial plane joint (gliding movement) that is formed between the lateral end of clavicle and acromion of scapula **Ligaments**: - **Superior & Inferior Acromioclavicular** ligaments: strengthen the joint capsule, prevent excessive clavicular movement - accessory ligament: **coracoclavicular ligament**: strongest stabilizer of the AC joint, connects clavicle to the coracoid process of scapula, prevents clavicle from displacing superiorly **movements**: gliding movement when scapula rotates or clavicle is elevated or depressed - works with SC joint to allow full shoulder motion *anterior: hits deltoid posterior: hits trapezius superiorly: skin*

Answer 50

**anastomosis**: network of interconnected blood vessels that allow blood to flow even if one artery is blocked (lots around scapula) - **suprascapular artery** (*passes over suprascapular notch to supply supraspinatus & infraspinatus muscles*) - **deep branch of transverse cervical artery or dorsal scapular artery** (*runs along the medial border of scapula, supplying the rhomboids and trapezius*) - **circumflex scapular artery** (*passes through the triangular space [right below quadrangular space] to reach back of the scapula, connecting with the suprascapular artery*) **function**: ensures blood supply to the scapular muscles & bones *mnemonic: "some teens can always party" - for all of the scapular anatomosis*

Answer 51

this anastomosis occurs around the top of the scapula, near the acromion - **acromial branch of the thoracoacromial artery**: comes from axillary artery, supplies acromion and shoulder joint - **suprascapular artery**: same as from scapula body, also supplies the acromion area **posterior circumflex humeral artery**: comes from the axillary artery, passes through the quadrangular space to supply the deltoid and shoulder joint **function**: provides blood to the shoulder joint & acromion *mnemonic: "some teens can always party" - for all of the scapular anatomosis*

Answer 52

bunch of muscle fibers in your neck that lie just under the skin - arises from deep fascia of **pectoralis major** & inserts on **base of mandible** (jaw) *may protect external jugular vein which underlies it*

Answer 53

*pectoral region - area in front of shoulder* 1. Pectoralis major 2. Pectoralis minor 3. Subclavius 4. Serratus anterior

Answer 54

pectoralis major & minor → **medial & lateral pectoral nerves** (pectoralis minor is only medial pectoral nerve) from the brachial plexus - nerve roots: **C6, C7, C8** (major), **C7** (minor) subclavius → **subclavian nerve** (aka nerve to subclavius, comes from upper trunk of brachial plexus) - nerve roots: **C5** serratus anterior → **long thoracic nerve** - nerve roots: **C6, C7**

Answer 55

**pectoralis major** → adduction of arm (bring back to side) & medial rotation of arm (move towards midline of body) **pectoralis minor** → depression of the shoulder (*when you push something down like pressing on a table*) & pulling ribs upwards when scapula is fixed (like when you take a deep breath)

Answer 56

**subclavius** → helps stabilize the clavicle & pull it down (depresses), steadies clavicle during movements of the shoulder joint **serratus anterior** → pulls scapula forward and around rib cage (*called boxer's muscle*), rotates scapula outwards in raising the arm above 90º (*abduction above 90º*)

Answer 57

stabilizes the shoulder joint *cuff has no muscles (deficient) inferiorly so this is a site of potential weakness*

Answer 58

**clavipectoral fascia**: strong sheet of connective tissue located under the pec. major muscle - connects the *clavicle (collarbone) to thorax* & surrounds the pec. minor muscle **deep pectoral fascia**: covers pectoralis major, attached superiorly to clavicle & anteriorly to sternum STRUCTURES PIERCING IT: **1. Lateral Pectoral Nerve** → this nerve supplies the pec. major muscle, helping with arm and shoulder movement **2. Cephalic Vein** → large vein that drains blood from the arm and carries it to the axillary vein **3. Thoracoacromial Vessels** → These arteries & veins supply blood to the shoulder, chest, and upper arm **4. Lymphatics from the Breast** → small vessels that help drain lymph from breast, playing a role in the body's immune system

Answer 59

1. cutaneous nerves (skin nerves) 2. cutaneous blood vessels (arteries that supply the skin) 3. platysma muscle 4. breast

Answer 60

2 sources of these nerves: **Cervical plexus** (neck nerves) → These supply the upper chest and neck. - *C3 and C4 (from the cervical plexus) supply the shoulder and upper chest* **Intercostal nerves** (from ribs) → These supply the lower chest and abdomen - *T2 and T3 (intercostal nerves) supply the lower chest and upper abdomen* *C3,4 directly overlap area supplies by T2,3* → some areas of the skin receive signals from both sets of nerves (why sometimes pain in heart is felt in shoulder too) - these nerves provide sensation to the skin in the chest area

Answer 61

**Internal thoracic artery branches** → Come from inside the chest. **Posterior intercostal artery branches** → Come from the back and supply the chest wall *these arteries deliver blood to the skin and superficial tissues of the chest*

Answer 62

its muscle fibers are arranged in multiple diagonal rows, attaching to several tendons - this structure **increases the strength** of the muscle by allowing more muscle fibers to fit into a small space - has anterior, posterior, and middle parts of the fibers

Answer 63

deltoid & teres minor

Answer 64

**flexion**: right arm goes out but also kind of to the left **extension**: right arm just goes downward and backwards

Answer 65

deltoid: **axillary nerve** supraspinatus & infraspinatus: **suprascapular nerve** teres major: **lower subscapular nerve** teres minor: **axillary nerve** subscapularis: **upper & lower subscapular nerves**

Answer 66

trapezius: spinal part of **accessory nerve** - nerve roots: cranial nerve latissimus dorsi: **thoracodorsal nerve** - nerve roots: **C7** levator scapulae: C3,4 **dorsal scapular nerve** rhomboid major & minor **dorsal scapular nerve** - nerve roots: **C4** only predominant nerve root listed

Answer 67

deltoid: anterior fibers **flex arm** (move forward) & **medially rotate the arm**; middle fibers **abduct arm** (lift sideways); posterior fibers **extend** and **laterally rotate** arm supraspinatus: starts arm abduction (**first 15º**) before deltoid takes over, stabilizes shoulder joint (rotator cuff) infraspinatus: **laterally rotates arm** & stabilizes shoulder joint (rotator cuff) teres major: **medially rotates** arm and stabilizes shoulder joint teres minor: **laterally rotates** arm and stabilizes shoulder joint subscapularis: **medially rotates** arm & stabilizes shoulder joint

Answer 68

trapezius: upper fibers **elevate scapula**; middle fibers **retract scapula** (pull back); lower fibers **depress** (lower) shoulder (medial border of scapula) latissimus dorsi: **extends, adducts, medially rotates** arm levator scapulae: **lifts** medial border of scapula rhomboid major & minor: **raises medial border** of scapula upwards & medially

Answer 69

supraspinatus starts (0-15º) → deltoid continues (15-90º) → serratus anterior & trapezius (90-180º- **overhead abduction**)

Answer 70

- pectoralis major - anterior fibers of deltoid - latissimus dorsi - teres major

Answer 71

- posterior fibers of the deltoid - infraspinatus - teres minor

Answer 72

- pectoralis major - latissimus dorsi - biceps long head - triceps long head

Answer 73

- pectoralis major (clavicular part) - anterior fibers of deltoid - coracobrachialis

Answer 74

- posterior fibers of deltoid - latissmus dorsi - teres major

Answer 75

*for every 3º of total arm movement, 2º comes from humerus moving while 1º comes from thescapula rotating* 1. Initial Phase **(0°–30° Abduction)** → mostly the humerus moves, with little scapular movement. 2. Middle Phase **(30°–90° Abduction)** → scapula begins to rotate upward with the humerus 3. Final Phase **(90°–180° Abduction)** → scapula rotates fully to allow maximum arm elevation

Answer 76

branches from **C5 root** supplies levator scapulae & rhomboid muscles

Answer 77

arises from **C5, C6, C7 roots** supplies serratus anterior (unusual passes through its superficial side rather than the usually belly of muscle - makes it more prone to injuries)

Answer 78

*lower and middle trunks dont have branches* **upper trunk**: - **nerve to the subclavius** (C5-6) which supplies subclavius muscle - **suprascapular nerve** (*passes through suprascapular notch then goes down to supply supraspinatus, more down to infraspinatus, and the shoulder joint*)

Answer 79

**lateral pectoral nerve**: supplies pectoralis major terminal branch is **muscular cutaneous nerve** also combines with medial cord to form the **lateral root of the median nerve** (median nerve has no branches in the axilla)

Answer 80

**medial pectoral nerve**: supplies pectoralis minor and major **medial cutaneous nerve of forearm**: supplies skin on medial side of forearm **medial cutaneous nerve of the arm**: supplies skin on medial side of arm **ulnar nerve**: no branches in the axilla (terminal branch) also joins with the lateral cord to form the **medial root of the median nerve** (terminal branch)

Answer 81

**upper & lower subscapular nerves**: supply upper & lower parts of the subscapularis muscle, lower also supplies teres major **thoracodorsal nerve**: supplies latissimus dorsi **axillary nerve**: passes through quadrangular space (terminal branch) **radial nerve**: largest branch of brachial plexus, gives off branches to heads of triceps muscle (terminal branch)

Answer 82

- "fight or flight" response - comes from **T2-T6 spinal segments** - fibers ascend to higher levels in the sympathetic chain before synapsing in the middle, inferior, and first thoracic ganglia - sympathetic stimulation causes *vasodilation in skeletal muscles for increased blood flow, vasoconstriction in the skin, sweating, and piloerection (goosebumps)*

Answer 83

**brachial plexus block**: type of regional anesthesia used to numb upper limb, often performed for surgical procedures, pain management, or trauma care - 3 TYPES: **1. interscalene block**: targets roots of brachial plexus (for shoulder surgeries) **2. supraclavicular block**: targets trunks (for elbow, forearm, or hand surgeries) **3. infraclavicular block**: targets cords (for lower arm and hand procedures) **axillary nerve block**: anesthetic injected into axillary sheath near axillary artery - commonly used for surgeries on the forearm, wrist, and hand

Answer 84

divided based off movement **anterior** → flexors (arm going forward) **posterior** → extensors (arm going backwards) divided by the **medial & lateral inter muscular septum** that are within the sheath of deep fascia that encloses the arm

Answer 85

- biceps brachii - coracobrachialis - brachialis **nerve supply** → musculocutaneous nerve (C5-C7) **blood supply** → radial artery *for all*

Answer 86

**origin**: middle third of medial surface of humerus **insertion**: coronoid process & ulnar tuberosity **function**: flexes forearm at elbow joint

Answer 87

**origin**: coracoid process of scapula **insertion**: middle third of medial surface of humerus **function**: flexes arm at shoulder joint

Answer 88

**origin**: short head from coracoid process of scapula, long head from supraglenoid tubercle of scapula **insertion**: radial tuberosity & bicipital aponeurosis (*aponeurosis- where muscles tendons meet*) **function**: strong supinator when forearm is flexed, all screwing movement done with it, short head is flexor of the arm, flexor of the elbow, long head prevents upwards displacement of head of humerus

Answer 89

arises from **lateral cord** of brachial plexus → travels with 3rd part of axillary artery in lower axilla → **pierces coracobrachialis** muscle near shoulder → travels down b/w **biceps & brachialis** muscles (supplies both) → continues down towards lateral side of arm → becomes **lateral cutaneous nerve of the forearm** once it goes into the forearm

Answer 90

the one that supplies joints

Answer 91

starts at **lower edge of teres major** (continuation of axillary) → travels medially alongside **median nerve** → goes in front of biceps & coracobrachialis →lies superficially in the middle of arm (*makes it easy to feel pulse there*) → end at cubital fossa (front of elbow) → divides into **radial** (lateral) and **ulnar** (medial) branches

Answer 92

1. **profunda brachii artery**: deep brachial artery, largest branch that runs with the radial nerve in the posterior compartment - supplies *triceps brachii* and contributes to the elbow anastomosis 2. **nutrient artery to humerus**: supplies bone marrow of humerus 3 & 4. **superior and inferior ulnar collateral artery**: both help in anastomosis of the elbow joint, superior is above the end of the humerus while inferior is below the end of the humerus

Answer 93

- brachial artery will have a little hole (lumen) in it (*nerves can never have lumens!!*) - median nerve will starts from 2 nerves (branches of the lateral & medial cord) - axillary nerve will be kati wee - ulnar nerve will be from the medial epicondyle

Answer 94

**muscle**: triceps (only 1 muscle in this compartment) **nerve supply**: radial nerve (C6, C7, C8) **blood supply**: profunda brachii & ulnar collateral arteries **structures passing through compartment**: radial & ulnar nerve

Answer 95

**origin**: - long head → infraglenoid tubercle of scapula (*long head originates from scapula, while lateral & medial heads originate from humerus - identifier*) - lateral head → above radial groove - medial head → below radial groove (*medial head is under the long & lateral heads*) **insertion**: all 3 heads insert into *olecranon process of ulna* via triceps tendon **function**: main extensor muscle

Answer 96

sole motor nerve of the posterior compartment of the arm & forearm - provides extensive cutaneous innervation along posterior aspect of the entire limb

Answer 97

originates from **posterior cord** of brachial plexus → passes behind (posterior) axillary artery → gives off branches to the long head of triceps brachii → travels along **radial groove** with the **profunda brachii artery** → supplies all 3 heads of triceps → pierces **lateral intermuscular septum** (*separates anterior & posterior compartments*) to enter the anterior compartment → travels b/w brachialis & brachioradialis → **lateral epicondyle of humerus**

Answer 98

arises from **medial cord** of brachial plexus → runs medial to axillary artery but **gives no branches in the axilla!!** → travels medial to brachial artery → pierces medial intermuscular septum & enters posterior compartment → passes behind medial epicondyle (**funny bone area!!**)

Answer 99

- arises from - brachial artery near its origin - accompanies **radial nerve in radial groove** of humerus - supplies **triceps** - takes part in **anastomosis** around elbow joint - ends by diving into **middle & radial collateral arteries**

gross- upper limb (osce I) Flashcards

(123 cards)