gross- clinicals upper limb (osce I & II)

Question 1

fracture of the clavicle

Answer 1

• commonly fractured by falling on outstretched hand
• common site of fracture is the junction b/w lateral and medial ends (weakest point)
• medial end goes up (pulled by sternocleidomastoid muscle)
• lateral end goes down (trapezius alone cannot support the whole upper limb)

Question 2

clinical: “winging of the scapula”

Answer 2

caused by paralysis of the serratus anterior where the medial border of the scapula becomes extremely prominent (SA can no longer pull the medial end towards itself)

• arm cannot be abducted 90º
• ask patients to push hands against wall to see this

also if the lateral thoracic nerve is damaged - patient cannot abduct arm above 90º angle b/c serratus anterior is paralyzed

Question 3

common fracture sites of the humerus + what nerve gets damaged then (+ common complications*)

Answer 3

surgical neck (proximal humerus) → axillary nerve
- deltoid muscle weakness, loss of sensation over lateral shoulder

shaft → radial nerve
- wrist drop (weak wrist & finger extension)

supracondylar region/medial epicondyle (common in young age) → ulnar nerve
- claw hand deformity, weak grip strength

Question 4

witch’s milk

Answer 4

temporary breast milk secretion in newborns, seen in both male and female infants

happens due to maternal hormones (estrogen and prolactin) that cross the placenta into the baby’s bloodstream

infant’s breasts may appear slightly swollen, and a small amount of milky fluid may be expressed

Question 5

supernumerary nipples

Answer 5

extra nipples that form along the embryonic milk line, which extends from the armpit to the groin

caused by incomplete regression of the mammary ridges during fetal development

• sort of resemble moles
  -more common in males but generally harmless

Question 6

retracted nipples

Answer 6

nipple is pulled inward (inverted) instead of projecting outward

• also congenital (had since birth bc of deformity)
• dangerous for new breastfeeding mother b/c infections go in and milk does not come out

recent nipple retraction (especially in one breast) can be a warning sign of cancer and needs medical evaluation

Question 7

Peau d’Orange

Answer 7

(name is french for “orange peel skin”)

dimpled, swollen appearance of the breast skin, resembling the texture of an orange peel

caused by blockage of lymphatic drainage, leading to fluid buildup (edema) in the skin

• most commonly seen in inflammatory breast cancer, an aggressive type of breast cancer.
• can also result from severe breast infections (mastitis) or lymphedema

requires urgent medical evaluation

Question 8

erb palsy aka upper brachial plexus injury (cause, symptoms, nerves & muscles damaged)

Answer 8

• injury to the C5 & C6 nerve roots of brachial plexus
• occurs b/c shoulder is forcefully pulled downward while head is tilted to opposite side (excessive pulling of neck)
• common in difficult childbirth or trauma (fall on head & shoulder from motorbike)

symptoms: “waiter’s tip hand” - limb hangs limply by the side, medially rotated, forearm protonated, sensation lost in lower half of deltoid & lateral side of forearm

nerves damaged: suprascapular, nerve to the subclavius, musculocutaneous, axillary nerves

muscles paralyzed:
- infraspinatus & supraspinatus (-suprascapular nerve)
- subclavius (-nerve to subclavius)
- coracobrachialis, biceps brachii, brachialis (-musculocutaneous)
- deltoid & ters minor (-axillary nerve)

Question 9

klumpke’s palsy aka lower brachial plexus injury (cause, symptoms, nerves & muscles damaged)

Answer 9

T1 interior ramus is torn, usually due to excessive abduction of the arm (person falling grabs tree branch to break fall) or pulling baby’s arm when delivering

T1’s nerve fibers run in the ulnar & median nerves to supply all the small muscles so hand gives clawed appearance

and if C8 anterior ramus is also damaged, then will involve medial side of forearm, hand, and medial 2 fingers

Question 10

what happens when radial nerve is injured at the origin of its branches? what about in the radial groove?

Answer 10

origin (near surgical neck): paralysis of the triceps, brachioradialis, supinator/extension of wrist & fingers, loss of sensation in areas of skin (cause the original source was damaged)

in radial groove: triceps are weakened not paralyzed (only the medial head is affected), muscles in the forearm are paralyzed though

Question 10

brachial artery occlusion/injury (+Volkmann’s Ischemic Contracture) imp

Answer 10

occluded = blocked → cut off blood flow

• brachial artery can be comprised at the mid-humeral level (middle of upper arm)

prolonged occlusion → volkmann’s ischemic contracture
- ischemia = lack of blood supply
- causes permanent muscle & nerve damage
- fingers and wrist become permanently flexed looking like a claw

Question 11

clinical: wrist drop + reason imp

Answer 11

characteristic sign of radial nerve injury!!!

wrist basically drops

reason: extension is lost, flexors are more dominant now so hand stays in flexion position (angle reduced in the wrist) + also weight of gravity pulling downward

Question 12

why does erb’s palsy result in waiter’s tip position?

Answer 12

C5, C6 roots damaged = every nerve that gets contributions from that damaged

supraspinatus → no abduction of shoulder
innfraspinatus → no lateral rotator of shoulder
both supplied by suprascapular
subclavius → no depression of shoulder (their shoulders are slightly elevated)
musculocutaneous damaged → flexors of ant. compartment of arm all gone = no flexion
axillary → teres minor & deltoid gone = no abduction/lateral rotation of arm

hand is pronated not flexed b/c biceps is powerful supinator

Question 13

erb’s palsy sensation loss

Answer 13

• skin over deltoid muscle, lateral part of upper arm (supplied by axillary)
• lateral forearm (supplied by musculocutaneous nerve)

Question 14

klumpke’s palsy is mainly what nerve damaged?

Answer 14

ulnar nerve

result is clawed hand

Question 14

long thoracic nerve damage + how to check if its damaged

Answer 14

**damaged*: serratus anterior lost = winging of the scapula

check: patient pushes against wall to see if scapula is coming out

Question 15

loss of musculocutaneous nerve results in what

Answer 15

motor: loss of flexion at elbow joint & supination

sensory: lateral part of forearm

Question 15

why is median nerve called “laborer’s nerve”?

Answer 15

manual laborers use grip, precision, and finger flexion a lot which all depend heavily on the median nerve

• motor supplies forearm muscles for flexion and thenar muscles

Question 16

what happens if median nerve is damaged in supracondylar fracture of the humerus?

Answer 16

• flexion of wrist gone
• adducted hand due to paralysis of flexor carpi radialis
• forearm kept supine bc of loss of pronators

benedict’s hand: when asked to make a fist, cant flex index, middle, and thumb properly
- pointing index finger

Question 17

what happens if median nerve is damaged at the wrist? (carpal tunnel syndrome)

Answer 17

• forearm alr supplied so mainly affects hand
• thenar eminence gone = ape hand deformity

Question 18

ulnar nerve injury at elbow vs. wrist

Answer 18

elbow
flexor carpi ulnaris & half of flexor digitorum profundus = weak flexion of ring & little fingers

wrist
most intrinsic muscles - hypothenar, interossei, medial 2 lumbricals, adductor pollicis = hand stays stuck in claw hand deformity and forment sign (cant pinch properly)

Question 19

rupture of long head of biceps brachii

Answer 19

• occurs due to wear and tear of the tendon in the intertubercular sulcus
• common in elderly individuals or those engaged in repetitive overhead activities (e.g., weightlifters, swimmers)
• leads to the formation of “Popeye deformity”—a bulge in the anterior arm due to retraction of the muscle belly

basically one tendon just lets go and one part of the muscle droops forward (Popeye is broken not buff)

Question 19

breast abscess

Answer 19

localized collection of pus within the breast tissue, usually due to a bacterial infection
- breast may look swollen, red, or painful

most commonly caused by bacteria, which enters through cracked nipples (common in breastfeeding women)

• may also develop due to mastitis (breast infection) or untreated cellulitis.

any tumor on breast should be considered cancerous unless proved otherwise

Question 20

boils in axilla

Answer 20

• axilla has a high concentration of hair follicles and sebaceous glands, making it a common site for infections like boils (furuncles)
• caused by bacterial infection due to sweat accumulation, friction, and poor hygiene

is painful, swollen, pus-filled lumps in the armpit

Question 21

spread of infection via axillary lymph nodes & axillary sheath

Answer 21

b/c axillary lymph nodes drain: - upper limb - breast - anterior chest wall above the umbilicus, **breast cancer can spread to axillary lymph nodes, making them important in staging cancer** infections from the anterior chest wall or arm can cause painful, swollen axillary lymph nodes

Question 22

axillary artery pulsation can be felt

Answer 22

axillary artery lies against the lateral wall of the axilla, making its pulsation easily palpable **clinical significance**: can be used to assess circulation in the upper limb - compression of the axillary artery (e.g., in cases of severe bleeding) can *help control hemorrhage before surgery or treatment*

Question 23

rotator cuff tendinitis

Answer 23

inflammation (swelling and irritation) of the tendons in the rotator cuff, pain occurs in **60º-120º abduction** **supraspinatus** → most commonly injured muscle in the rotator cuff - during abduction, supraspinatus tendon is exposed to friction against acromion - normally, *subacromial bursa* takes the friction but overuse can cause the bursa to degenerate **causes**: wear and tear (wear → age related), overused overhead movements (athletes like baseball players) clinical names: **subacromial bursitis, supraspinatus tendinitis, pericapsulitis**

Question 24

anterior-inferior dislocation of shoulder joint

Answer 24

basically head of humerus goes under the glenoid cavity - caused by sudden violence when joint was fully abducted → tears weak part of capsule **subglenoid displacement**: humeral head moves directly below glenoid cavity → can cause damage to **axillary artery** → 1/3 of deltoid becomes paralyzed → *abduction + lateral movement gone* (motor loss) and *loss of skin sensation* over *lower half of deltoid* gone (sensory loss) *need to mention both sensory and motor losses!!*

Question 25

injury to the musculocutaneous nerve

Answer 25

when mc nerve damaged → the muscles (biceps, brachialis, coracobrachialis) are damaged → weak flexion of elbow, supination is weakened → sensation lost in lateral portion of forearm (*due to involvement of the lateral cutaneous nerve of the forearm, branch of MC nerve*) *need to mention both sensory & motor loss*

Question 26

bicipital tendinitis

Answer 26

**inflammation of the long head(!!)** of the biceps tendon within the intertubercular groove - common in athletes performing repeated overhead motions (e.g., tennis, baseball) - causes pain and tenderness along the anterior shoulder

Question 27

Pre-fixed and Post-fixed Brachial Plexus

Answer 27

- caused by variations in its formation **normal brachial plexus**: arises from C5, C6, C7, C8, and T1 spinal nerves **pre-fixed brachial plexus**: contribution starts higher than normal- *C4 to C8* instead of C5 to T1. - T1 contribution is either absent or reduced - less innervation to lower part of limb (hand muscles b/c of less contribution of T1) **post-fixed brachial plexus**: contribution shifts lower than normal- *C6 to T2* instead of C5 to T1 - C5 contribution is either absent or reduced - may cause weaker shoulder muscles b/c of less C5 involvement

Question 28

damage to radial nerve occurs through what

Answer 28

- **saturday night palsy**: guy is sitting with an arm over the chair and its pushing into the axilla - same with **crutch palsy** - fracture/dislocations of the shaft of the humerus - faulty technique of intramuscular injection - prolonged application of tourniquet to arm