shoulder and arm Flashcards
what are the bones in the shoulder and arm *
scapular
clavical - collar bone
humerous
describe the scapular *
triangular flat bone
spine of scapular separates the supraspinous fossa and infraspinous fossa
acromion is the lateral end of the spine of the scapular - has small oval facet to articulate with clavicle
coracoid process - anterior hooik of bone protuding forward
lateral - cup like structure where scap is widened forming a socket for shoulder joint which is ball and socket - this is the glenoid cavity/fossa
has superior, lateral and inferior angle
the infraglenoid tubercle is located superior to glenoid cavity - site of attachment for long head of biceps brachii muscle
lateral border is strong and thick for muscle attachments, whereas medial and much of superior border is thin and sharp
suprascapular notch lies immediately medial to root of corocoid process
identify anterior and posterior surface, medial border, supraspinous fossa, infraspinous fossa, superior inferior and lateral angles (geometric where glenoid fossa is), greater scapular notch, subscapular fossa
descibe the clavical *
it is a small long bone
one of 1st bones to start calcification and one of last to stop - some still calcifying at 22
s shaped
flattened laterally at the acromial end - articulates with acromium of scapular
sternal end has a flat facet - articulates with the manubrium
inferior surface of lateral 1/3 has conoid tubercle and lateral roughening (traoezoid line) for attachment of coracoclavicular ligament
smooth superior surface and rough inferior surface
identify conoid tubercle and subclavian groove
describe the humerous *
long bone
straight shaft
ends widened and have features for articulation
anatomical neck is true neck of bone
surgical neck is where breaks occur commonly
deltoid tuberosity - where proximal part of deltoid muscle attaches
condyles - articular part of the sdistal bone these are capitulum and trochlear
epicondyles - lateral and medial are bony bitsabove the condyles
greater tuberosity is lateral
lesser tuberosity is medial
identify the: coronoid fossa, olecranon fossa, radial fossa, medial and lateral supracondylar ridges, medial and kateral epicondylesm capitulum (lateral), trochear (medial), intertubercular groove, radial groove
hat is teh difference between a tuberle and tuberosity
tbercle is rounder
what is the pectoral girdle *
shoulder girdle - clavicle and scapular
made of chest and back
what are the compartments for the shoulder and arm *
anterior pectoral girdle muscle
posterior pectoral girdle muscle
intrinsic shoulder muscles
anterior compartmet of upper arm
posterior compartment of upper arm
what are the muscles in the anterior pec girdle compartment *
pec major
pec minor
subclavius
serratus anterior
(all chest muscels except serratus - runs anterior and posterior)
describe the pec major *
gives definition to superior part of chest
broad attachments superiorly
proximal attachments: medial 1/3 clav, the sternum and manubrium and 1st 7 cc, sternal end of 6th rib and external oblique’s aporneuosis
distal attachment: lateral lip of intertubercular groove - fibres converge here
function: adducts and medially rotates humerous, lesser actions on scapular, has flexion functions
innervation: medial and lateral pectoral nerves, clavicular head - C5 6, sternocostal head - C6-T1
blood- thoracoacromial artery, lateral thoracic artery
describe the pec minor muscle *
proximal attachment: coracoid process of scapular
anterior surfaces and superior border of rib 3-5 and from deep fascia overlying the related intercostal spaces
fan out into digital (finger like) parts
attach to 2nd-5th ribs
function: act on scap - pull forward and down
innervation: medial pectoral nerve C5-T1
describe the subclavius muscle *
distal attachment - inferior part of cavical
proximal - 1st rib close to costochondrial joint
function: act on clavical relative to trunk, stabalise the clavical
innervation: nerve to subclavius C5-T1
describe serratus anterior *
has a wide attachment
attach to medial part of scap
run anteriorly over surface of thoracic cage and attach to ribs 1-9 anteriorly and deep fascia and overlying the intercostal spaces
function: hold scapular onto thoracic wall, protract scapula, assist in upwards rotation
innervation: long thoracic nerve c5 6 7
blood - lateral thoracic artery and thoracodorsal artery
what are the muscles in the posterior pectoral girdle compartment *
trapzius
latissimus dorsi
levator scapulae
the Rhomboids
describe the trapezius *
1 trapezius muscle on each side - meet in midline
attachment: nuchal line of skull and external occipital proturbance, ligamental nuchae and spine of cervical and thoracic vertebrae to T12
descending part of trapezius - fibres come down
middle part - fibres come across
ascendoing part - fibres go up
anterior attachment to acromium and clavical (curls round to front) and superior spine of scapula, posterior border of lateral1/3 of clavical
innervation: spinal accessory nerve, ventral rami c4 5
function: act on scap - elevates, upward rotation, downward rotation, retraction
blood supply - transverse cervical artery
describe the latissimus dorsi *
attach proximally: at iliac crest forming thoracolumbar facia, attach to upper 2-3 sacral segments and spines to T8, lower 3 or 4 ribs
attach distally: fibres converge to form strap like tendon that attaches to floor of intertubercular groove
function: extends, adducts and roatates humerous, pulls body up during climbing, important in rowing
innervation: thoracodorsal nerve c6 7 8
blood - thoracodorsal artery
describe the romboids *
made of minor and major
minor is a single strap - from spinous process of c7-t1, ligamentum nuchae and supraspinous ligament to medial scapular
major - parallelogram of muscle
major attaches to spinous process of lower neck and upper thoracic T2-T5 and intervening supraspinous ligaments - insert to medial scapular
function: retracts, rotates, elevates and fixes the scapular
innervation: dorsal scapular nerve c4 5
blood - transverse cervical arteyr or dorsal scapular artery
describe the levator scapulae *
attach superior angle of scapular
attach transverse process of C1-C4
function: rotate and elevate scap
innervation: dorsal scapular nerve, C3 C4
blood - transverse cervical artery
what are the intrinsic shoulder muscles *
deltoid - goes over the shoulder joint, gives rounded appearance
teres major
the rotator cuff muscles (supraspinatus, infraspinatus, teres minor, subscapularis) - intrinsically associated with scap, insert at head of humerous
describe the deltoid muscle *
attach to spine of scap, acromion and lateral part of clavical (clavical is the anterior attachment)
insert to deltoid tuberosity of humerus
fibrs can act separately for different func - eg extend and flex
func of deltoid as whole: abducts
anterior portion = flexion and medial rotation
posterior portion - extension and lateral rotation
blood supply - posterior humeral circumflex artery, deltoid branch of thoracoacromial artery
innervation: axillary nerve c5 6
describe the rotator cuff *
all head over shoulder to attach to ehad of humerous
function: fix head of humerous in glenoid fossa
function of supraspinateous: initiating abduction for 1st 15degrees - then deltoid takes over
cover the scapular
prox attachment: scap
terus minor - straight muscle from the posterior surface of the scapula adjacent to lateral border of scapula
all have individual func
supraspinatus and infraspinatus muscles in supra/infraspinus fossa respectively
insert into greater tubercle of the humerus
describe the terus major *
innervation: lower subscapular nerve c5 6
distal attach in intertubercular sulcus of humerus
prox attach: postrior surface of the inf angle of scap
function: move shoulder, adduct and rotate arm, assists in extension from a flexed position
blood - thoracodorsal artery
what are the muscles of the anterior compartment of the arm *
biceps brachii
coracobrachialis
brachialis
describe biceps brachii *
2 heads
long head more lateral - attach at supraglenoid tubercle of scapula
short - Prox attach: coracoid process of scap
long go through the intertubercular groove of humerus, ligament holds it in place, it crosses over shoulder joint and attahes to tubercle at superior rim of glenoid fossa - supraglenoid tubercle
the 2 heads merge distally
distal attachment - elbow - form tendon that attaches to radial tuberosity, and the bicep aporneurosis (thin sheet like structure that merges with facia)
func: powerful flexor of forearm at elbow joint and supinator of forearm, accessory flexor of arm at GHJ, stabalise anterior aspect of shoulder and flexes shoulder (weak)
innervation - musculocutaneous C5 6
blood - brachial artery
descrieb brachialis *
function: elbow flexion
attach: middleshaft of humerous, intermuscular septa
cross elbow joint then attach to coronoid process of ulna adn ulnar tuberosity
innervation - musculocutaneous c5 6
blood - brachial artery and radial recurrent artery
describe the coracobrachialis *
comes from coracoid process
forms spindle shpaed muscle
runs distally ajnd attaches to medial shaft of humerous
function: adduct and act across shoulder joint
innervation of the anterior compartment of the arm *
musculocutaneous nerve
what are the muscles of the posterior compartment of the arm *
triceps
anconeus
what is the innervatioon of the posterior compartment of the arm *
radial nerve
describe teh triceps brachii *
3 heads
lateral and medial attach to posterior shaft of humerus and intermuscular septum
long head crosses shoulder and attaches to infraglenoid tubercle of scapula
tehy converge to form triceps tendon, which crosses elbow joint and attaches posterior to ulnar’s olecranon process and deep fascia of antebrachium
function: extensor at elbow joint
- long head extends at the shoulder and a little elbow flexion,
- lateral and medial extends teh forearm at elbow
innervation - radial nerve c6 7
blood - brachial artery, ulnar collateral artery, profunda brachii artery
describe teh anconeus *
proc attach: humerus
distal attach: posterior ulna
func: exntension of elbow - main func is to stabalise joint in prontion and supination
what are the joints of the shoulder and arm *
sterno-clavicular joint SCJ
acromo-clavicualr joint ACJ
gleno-humeral joint GHJ (shoulderjoint)
scapulo-thoracic joint STJ (virtual/physiological joint)
elbow joint
joints of the pectoral girdle *
SCJ - synovial and has interarticular disk
ACJ - acronium and scapula
GHJ - not really but is included
STJ
describe the gleno-humeral joint *
between glenoid fossa and head of humerous - covered in hyaline cartilage
ball and socket synovial joint
it is multiaxial
glenoid fossa is shallow
the 2 glenoid labrums are rims of cartilage that deepen fossa and give it stbility
rotator cuff muscles superior, anterior and posterior are required for stability
acronium and edge of scap superiorly
prone to disslocation inferiorly
the rotator cuff depresses the humeral head
capsule of shoulder joint extends from glenoid to humeral head and has 2 other extensions
- subacromial fossa - capsule extends above humoral head to form a bursa between humeral head and acromial process - common site of pathology
- an extension along head of biceps as it lies in intertubercular groove of humerus
coroco-acromial arch is above GHJ - consists of acromion, the corocoid process and coraco-acromial ligament running between the 2 - arch prevents humerus rising superiorly against acromion
beneath the coraco-acromial arch is the subacromial bursa and supraspinatus tendon - site of path for impingement of shoulder
what are the movements of the shoulder jont GHJ adn muscles involved *
rotate shoulder and clavical
flexion, extension
abduction, adduction
medial and lateral rotation
circumduction
what are the movements of the STJ *
this joint is the contact between the scap and thoracic wall
elevation/depression scap
protraction (forward and lateral movement against cehst wall) /retraction of scap (back and medial)
rotation of scap
what is the axilla *
the gateway for nerves and bv to enter and leave upper limb
shaped like pyramid
transition between shoulder and arm
goes down to 5th rib
what does the axilla contain *
axillary arteruy and branches
axillary vein and tributaries
(at inlet - axillary vein is medial and anterior to artery which is anterior to brachial plexus. as vein and artery pass over rib 1 they are separated by insertion of scapula muscle)
lumphatic vessels and nodes
the infraclavicular part of brachial plexus lies on rib 1 - long thoracic and intercostobrachial nerves
long thoracic nerve enters axilla inlet and passes down medial wall of axilla
the 3 trunks of the brachial plexus originate from roots, pass laterally over rib 1 and enter axilla
what are the walls of the axilla *
base is composed of skin, subcutaneous tissue and fascia extending from arm to chest
inlet - medial margin is the lateral border of rib 1, anterior margin is posterior surface of clavicle, posterior margin is superior border of scapular up to coracoid process
apex lies between 1st rib, clavical and superior border of subscapularis muscle
anterior wall formed by pec major and minor and subclavial muscles and clavipectoral fascia
posterior wall formed by lat dorsi and terus major inferiorly and scap and subscapularis superiorly and long head of tricep brachii muscles
medial wall formed by chest wall 1st-4th ribs and serratus anterior
lateral wall formed by intertubercular groove of humerus
what is the path of the arteries in the shoulder and upper arm *
subclavian artery arises from aorta (L) or R brachiocephaic artery (R) - runs towards axilla in root of neck
subclavian arteyr goes under clavical and over 1st rib
becomes axillary artery - divided into 3 parts according to relation to pec minor - superior deep and inferior, and gives off branches in axilla
arteries give off branches to scap - well supplied for movement
when axillary crosses anterior border of terus major it becomes the brachial artery - in distal part of arm runs along median nerve
brachial artery enters the forearm - divides at elbow into radial and ulnar
branches anastomose around surgical neck - supplying blood to head and joint
brachial artery gives off the profunda brachii artery - deep muscle of arm - this is the biggest branch
extensive anastomoses at elbow
what is the path of veins in the shoulder and arm *
dorsal venous network in hands
form cephalic - runs up lateral border of arm, and basilic - medial
cephalic - passes deep into groove between pec major and deltoid (delto-pectoral groove), joins axillary, becomes subclavian
basilic - stays superficial, then goes deep in arm by passing through deep fascia, joins venae comitantes of brachial artery (brachial veins) to form axillary in arm
lateral thoracic vein joins axillary
thoracoepigastric vein connects superficial epigastric vein to lateral thoracic vein - acts as a shunt for blood if portal system develops hypertension or a blockage
axillary becomes subclavian at 1st rib
image for the deep veins of the region *
what is the lumphatic drainage of the shoudler and upper limb
superficial and deep systems run with veins
lymph drains from hand via superficial lymphatics alongside brachial and cephalic veins
some lymphatics pass directly and superficially up arm but there are some nodes
cubital lymph nodes - medial side of cubital region
delto-pectoral nodes alongside cephalic
axillary nodes - important for cancer drainage, drain the breast, drain lymph from superficial system
there are also deep lymphatics that run along deep veins and terminate in axilla region
subclavian lymph trunk
describe the bracjhial plexus *
roots form C5-T1
pass under clavical
form trunks in posterior triangle of neck, then divisions behind clavical, then cords in axilla close to axillary artery, then terminal branches
terminal branches are peripheral nerves
some terminal branches come off earlier eg dorsla scapula and long thoracic
long thoracic supplies serratus anterior
describe what the branches of teh brachial plexus supply *
long thoracic - serratus anterior
lateral and medial pectoral - pec major ad minor
musculocutaneous nerve - anterior compartment of arm
median nerve - peripheral nevre, pass through arm, supply forearm
ulna nerve - from brachial to forearm - supplies forearm and hand
posterior part of brachial plexus gives off axilla and radial nerve
axillary supplies deltoid and terus minor muscles, area of skin over deltoid
radial supplies posterior muscles
thoracodorsal nerve - latissimus doris muscle
suprascapular and upper and lower subscapular nerves supply rotator cuf muscles
median nerve
what are common sites of nerve injury
ulna nerve in cubital fossa
shoulder dislocation
