Upper limb 1 Flashcards
What is the axilla?
pyramidal space below the shoulder joint
Function of axilla
passageway for vessels and nerves going to and from the upper limb
Anterior wall of axilla
pec major & pec minor
Posterior wall of axilla
teres major & subscapularis
Medial wall of axilla
serratus anterior & thoracic wall
Lateral wall of axilla
intertubercular groove of humerus
The axillary artery is the continuation of which artery?
subclavian
at what anatomical point does the axillary artery start?
lateral border of 1st rib
Axillary artery continues beyond the axilla as which vessel?
brachial
At what anatomical point does the axillary artery become the brachial artery?
distal to inferior border of teres major
When may compression of axillary artery be necessary?
profuse bleeding due to severe injury of upper limb
What forms the brachial plexus?
ventral rami of C5-T1
major branches of brachial plexus
Musculocutaneous
Axillary
Median
Radial
Ulnar
(My Aunt Makes Ridiculous Umbrellas)
Which nerves roots form upper trunk?
C5 & C6
Erb’s point and clinical relevance
Union of C5 &C6
Can be injured at birth (shoulder dystocia) or fall on shoulders (hyperextension)
Can paralyse arm muscles -> waiter’s tip
Waiters tip position
Erb’s palsy
Medially rotated & wrist flexed
Which group of muscles affected in erb’s palsy?
Those innervated by the musculocutaneous nerve and the axillary nerve (and some of the radial nerve)
Musculocutaneous nerve: (BBC) Biceps Brachialis Coracobrachialis
Axillary nerve: Deltoid, teres minor,
Suprascapular nerve (C5-C6): Infraspinatus and supraspinatus
Radial nerve (partially): Wrist extensors
Roots of lower trunk of brachial plexus
C8 & T1
Klumpke’s palsy
Paralysis of: Intrinsic muscles of hand
Ulnar flexors of wrist and fingers
Causes claw hand
Lower trunk affected
Affects C8-T1
Cause of klumpke’s palsy
Undue abduction of arm
How are the cords of the brachial plexus named?
In relation to axillary artery
Brachial plexus nerves and their cords
Lateral cord -> muscluocutanous & median
Posterior cord -> axillary &radial
Medial cord -> ulnar & median
Where do the cephalic and basilic veins arise?
Cephalic -> lateral end of dorsal venous arch
Basilic - medial end of dorsal venous arch
What is the median cubital vein?
Large communicating vein shunting blood from cephalic to basilic vein
Dermatome
area of skin supplied by one spinal segment
Where do all upper limb lymphatic vessels drain?
Axillary LN
5 distinct axillary LN groups
Pectoral (anteiror)
Subscapular (posteiror)
Apical
Central
Lateral
Why can infected umbilicus spread to axillary and superficial inguinal LN?
Inguinal watershed region
Boudry at which lymph can spread up and below
Pectoral girdle
Connects upper limb to axial skeleton
involves only the scapula and clavicle
Upper limb and pectoral girdle articulating point
Acromioclavicular (AC) joint
Clavicle break
Inbetween the medial and lateral 1/3rds
AC joint is a type of
Synovial plane
Sternoclavicular joint is a type of
Synovial saddle
Movement of shoulder joint involves what?
Acromioclavicular (AC)
Sternoclavicular (SC)
Gelnohumeral
Scapulothoracic
Scapula-humeral rhythm
Beyond 90 degrees of abduction…
For every 3 degrees of abduction:
2o -> glenohumeral
1o -> scapula-thoracic
Elevation of scapula is caused by
Levetor scapulae
Trapezius
Rhomboids
Depression of scapula is caused by
Lower trapezius
Serratus anterior
protraction of scapula is caused by
Serratus anterior
Pec major and minor
Retraction of scapula is caused by
Middle fibres of trapezius
Rhomboids
Lateral rotation of scapula is casued by
trapezius (superior and inferior)
serratus anterior
medial rotation of scapula is caused by
Rhomboids
pec major
levator scapulae
gravity
Glenohumeral joint type and what each part is
synovial ball and sockek
ball= humeral head
socket= glenoid cavity
Rim of cartilage around glenoid cavity
glenoid labrum
Glenoid labrum function
Insertion for structures
Deepens socket
increases stability
Prevents discloations
Glenohumeral ligament strengthens what aspect of the joint
Anterior aspect of joint
Coracohumeral ligament strengthens what aspect of the joint
Superior aspect of joint capsule
Coraco-acromial arch is made up of
Acromion
coracoid process
coracoacromial ligament
function of coraco-acromial arch
Prevents displacement of humeral head
What part of shoulder joint is weakest and why?
Inferior part
Its not protected by any muscles or ligaments
Which shoulder bursa communicates with joint cavity?
Subscapular
Subacromial bursa function
Facilitate movement of supraspinous tendon and deltoid over joint capsule
Subacromial bursa injury
Dislocation of glenohumeral joint
4 rotator cuff muscles
Teres minor
Subscapularis
Supraspinatous
Infraspinatous
Glenohumeral joint movements by rotator cuff muscles
Abduction
External and internal rotation
Rotator cuff main function
Stability
Deltoid attachments
Lateral spine of scapula
acromion
lateral third of clavicle
delotoid tuberosity of humerus
Anterior fibres of deltoid actions on glenohumeral joint
Flexion
Medially rotation
Middle fibres of deltoid actions on glenohumeral joint
Abduction (its main function)
Posterior fibres of deltoid actions on glenohumeral joint
Extension
Lateral rotation
Nerve supply to deltoid
Axillary nerve
(posteior cord -> C5/6)
Common injury trapping axillary nerve
Surgical neck of humerus fracture
Loss of sensation of axillary nerve
Regimental badge area
Lateral arm
Origin of pec major fibres
Medial 1/3rd of clavicle
sternum
ribs
Pec major actions on glenohumeral joint
Flexion
Adduction
Internally rotation
Deltopectoral triangle
Space below clavicle & between:
deltoid
pec major
cephalic vein
Nerve supply of serratus anterior
Long thoracic nerve
C5, 6 & 7
Injury to long thoracic nerve and when this could happen
Winged scapula
Radial mastecomy (surgery for breast cancer)
Superior fibres of trapezius actions on scapula
Elevation
Medial fibres of trapezius actions on scapula
Retraction
Inferior fibres of trapezius actions on scapula
Depression
Trapezius innervation
CN 11 -Accessory nerve
Teres major action on glenohumeral joint
Adduct
Medial rotation
Lattisimus dorsi action on glenohumeral joint
Extension
Adduction
Medial rotation
what muslces cause Lateral or external rotation of glenohumeral joint
Teres minor
infraspinatus
What muscles does the brachial plexus lie in between?
Middle and anterior Scalene muscles
What is the only bursa in the shoulder that communicates with the shoulder joint?
Suscapular bursa
What is the innervation of the pectroalis major
Medial pectroal nerve
Lateral pectoral nerve
Klumpke’s palsy affects the lower trunk, which is C8-T1. What is the risk if T1 being affected?
(i.e. what syndrome is Klumpke’s linked to)
Horner’s syndrome
Resulting in ptosis and miosis (constriction of pupil)
What are the 3 clinical tests for shoulder ligament injuries?
TOSSY classification
10kg test
Piano key test
What type of bone is the scapula
Flat bone
What type of bone is the clacvicle
Long bone
What is the shape of the clavicle
S shaped
Medial aspect -> concave
Lateral aspect -> convex
Which lymph nodes is invloved in the following injuries…
Infection of little finger
Boil in scapular region
Lateral part of th breat
Infectoin around the umbilicus (along with the superficila inguinal)
AXILLAAAARRRYYYYYYY
What muscles attach to the greater tubercle of the humerus
Supraspinatus
Infraspinatus
Teres minor
What muscles attaches to the lesser trocanter of the humerus
Subscapularis
What is the only rotator cuff muscle that does not insert on the greater tubuercle of the huemrus
Subscapularis
(inserts on the lesser tubercle)
What muscles attach to the intertubercular sulcus
Latissums dorsi
Teres major
Pec major
What muscles attach onto the medial epicondyle
Flexor carpi radialis
Flexor carpi ulnaris
FDS
Palmaris longus
What muscels attach to the coaracoid process
Coracobrachialis
Pec minor
Short head of biceps brachii
What muscles attach to the supraglenoid and infragelnoid tubercle
Supraglenoid -> long head of biceps
Infraglenoid -> long head of tricpes
What muscles attach to the acromion and clavicle
Deltoid
Trapezius
