Posterior and Anterior Upper Limb Session 16+17 Flashcards
what is the clavicle
S shaped bone
Easily palpable in most individuals
What r the two joints of the clavicle and what type r they
synovial joints
1) sternoclavicular joint: articulates with the sternum at its medial end
2) acromioclavicular joint: articulates with the acromium of the scapula at its lateral end
What bony structure is on the posterior surface of the scapula
ridge of bone called the spine of scapula
What is the acromium
formed by the expansion of the lateral end of the spine of the scapula
What is the pectoral girdle made of
clavicle, scapula and the attached muscles
where is the glenoid fossa and what does it form
lateral aspect of the scapula
forms the shoulder by articulating with the proximal humerus
what r the supraglenoid tubercle and infraglenoid tubercles
two small projections of bone superior and inferior to the glenoid fossa of the scapula
What is the humerus
long bone of the arm
What is the anatomical neck of humerus
ring around head of the humerus
What is the greater tubercle
projection of bone on the lateral aspect of the proximal humerus (site for muscle attachment)
What is the surgical neck and what runs close to this region
where the humeral bone narrows and becomes continuous with the shaft
axillary nerve
what bone and where is the deltoid tuberosity on and what is it the site of
slight protuberance on lateral aspect of humeral shaft
site of attachment for the deltoid muscle
What is the radial groove and where is it
path of radial nerve
posterior upper humeral shaft
Name the 5 movements of the scapula and demonstrate them
protraction, retraction, elevation (shrugging), depression (squaring), rotation
How does the scapula help with rotation (2)
tilts the glenoid fossa cranially to aid elevation of the upper limb
for every 2 degrees of abduction of the shoulder, the scapula rotates 1 degree eg when raising the arm above the head
What r the two superficial muscles of the posterior pectoral girdle and briefly explain them
trapezius, latissimus dorsi
large flat muscles with extensive attachments to the vertebral column
What r the 3 deeper muscles of the posterior pectoral girdle and what is their common general attachment
levator scapulae, rhomboid major and rhomboid minor
muscles are attached to the medial border of the scapula to the vertebral colum
What is the movement of trapezius (hint: 3 parts)
upper part= elevates, middle= retracts, lower= depresses and rotates the scapula
What is the movement of latissimus dorsi (hint DEDM- dead to me)
elevates, adducts and medially rotates the humerus
What is the movement of levator scapulae
elevates
What is the movement of rhomboid major and minor
retracts
What r the attachments of trapezius
origin attachment: skull, cervical and thoracic vertebrae
insertion attachment: clavicle and scapula
What r the attachments of latissimus dorsi
origin attachment: lower thoracic vertebrae
insertion attachment: upper anterior humerus
what are the attachments of levator scapulae
origin attachment: upper cervical vertebrae
insertion attachment: medial border of scapula
what r the attachments of rhomboid minor
origin attachment: C7 and T1
insertion attachment: medial border of scapula
what r the attachments of rhomboid major
origin attachment: thoracic vertebrae
insertion attachment: medial border of scapula
What innervates the trapezius
11th cranial nerve (spinal accessory)
What innervates the latissimus dorsi
branch of brachial plexus called the thoracodorsal nerve
What innervates most of the muscles of the posterior pectoral girdle and what is the only exception
innervated by nerves from the brachial plexus
exception: trapezius
What r the 6 movements of the shoulder joint (make sure u can demonstrate this)
flexion, extension, abduction, adduction, medial and lateral rotation
What is the significance of the loose joint capsule at the shoulder
poor fit of the articular surfaces of the shoulder joint
allows for an extensive range of movement at the shoulder joint
this compromises stability ie shoulder dislocation
What r the 2 functions of the muscles that attach the scapula to the humerus
move and stabilise shoulder joint
What r the 6 muscles that attach the scapula to the humerus
deltoid supraspinatus infraspinatus subsccapularis teres major teres minor
What makes up the rotator cuff
supraspinatus, infraspinatus, subscapularis, teres minor
what r the intrinsic muscles of the scapula (5)
supraspinatus infraspinatus subsccapularis teres major teres minor (all muscles attached to scapula except the deltoid)
What is the origin of the deltoid
lateral part of clavicle to the spine of the scapula
What r the 3 movements of the deltoid muscle?
does abduction at shoulder joint (but deltoid cannot initiate abduction- only does abduction after 20 degrees)
anterior fibres contribute to flexion of arm
posterior fibres contribute to extension of arm
Innervation of deltoid and what is this a branch of
axillary nerve (branch of brachial plexus)
main action of deltoid at the shoulder joint
abduction beyond 20 degrees
Origin of deltoid
what structure does it also originate on in between these two structures
spine of scapula and clavicle
acromium
Insertion of deltoid on the humerus
deltoid tuberosity
Action of teres major at the shoulder joint
medial rotation and adduction
Origin of teres major from the scapula
posterior surface, inferior part of the lateral border of scapula
Teres major insertion on the humerus
anterior humerus- intertuberculor sulcus
Supraspinatus action at the shoulder joint
first 20 degrees of abduction
Supraspinatus origin from the scapula
supraspinous fossa
Supraspinatus insertion onto humerus
greater tubercle- superior facet
Teres minor action at the shoulder joint
lateral rotation
Teres minor origin from the scapula
lateral border of scapula
Teres minor insertion on the humerus
Greater tubercle- inferior facet
Infraspinatus action at the shoulder joint
lateral rotation
Infraspinatus origin from the scapula
infraspinous fossa
Infraspinatus insertion on the humerus
greater tubercle- middle facet
Subscapularis action at the shoulder joint
Medial rotation
Subscapularis origin from the scapula
Subscapular fossa
Subscapularis insertion onto the humerus
Lesser tubercle
the two ways the rotator cuff muscles maintain stability of the shoulder joint
- contraction of the rotator cuff muscles holds the head of the humerus in the shallow glenoid
- tendons fuse with the capsule of the shoulder joint
What 4 structures contribute to stability of the shoulder
muscles of the rotator cuff
glenoid labrum: rim of fibrocartilage around the margin of the glenoid fossa
ligaments: reinforces capsule
tendon of biceps brachii: reinforces the joint
What is the arm
in between shoulder and elbow
what is the intermuscular septa
extends from the deep brachial fascia
separates the arm into the anterior and posterior compartments
What is the muscle that lies on posterior of arm
triceps brachii
What is the action of Triceps brachii
extends the elbow when it contracts
how many muscle heads r there on the Triceps brachii and what r their names
3: long head, lateral head, medial head
long head of Triceps brachii: origin, location in relation to other heads, action
arises from infraglenoid tubercle of the scapula
most medial part of triceps
extension of shoulder joint as it is attached to the scapula
Where is the lateral head of Triceps brachii located
posterior humerus
Where is the medial head of Triceps brachii located
posterior humerus
Where do the 3 heads of the triceps brachii converge
via a common tendon onto the olecranon of the ulna
What is the innervation of the heads of the triceps brachii
radial nerve
what is the path of the radial nerve in the posterior arm
winds around the posterior aspect of the humerus in the radial groove between the medial and lateral heads of triceps
What r the structures of the bone on the upper part of the humerus (8)
head, anatomical neck, surgical neck, greater and lesser tubercle, intertubercular sulcus, deltoid tuberosity and radial groove
What r the structures of the bone on the lower part of the humerus (4)
medial and lateral epicondyles, trochlea and capitellum
What is the axilla and what shape is it
armpit, pyramid-shaped
What are the 4 structures in the axilla
lymph nodes, axially artery, axillary vein, brachial plexus
what r the general names (not structures) of the 6 boundaries of the axilla
what is the apex and base in between
anterior wall, posterior wall lateral wall, medial wall apex and base apex= between the back and the axilla base= between the chest wall and the arm
if struggling to visualise see: https://teachmeanatomy.info/upper-limb/areas/axilla/
What r the 6 boundaries of the axilla
anterior wall: pec major and minor
posterior wall: subscapularis, teres major and latissimus dorsi
lateral wall: upper humerus
medial wall: serratus anterior and chest wall
apex: first rib, clavicle and scapula
base: skin and fascia
what area the axillary lymph nodes drain (4)
how many groups of lymph nodes r there
what r the lymph nodes in the apex of the axilla called and why r they important
drains upper limb, chest, abdominal wall and umbilicus
5 groups of lymph nodes in the axilla
lymph nodes in the apex of the axilla- apical nodes receives lymph from all the other lymph nodes
what is the axillary artery continuous with
whys is the axillary artery important
how many branches does the axillary artery have
where do these branches come off
where does the axillary artery change name and what to
continuous with subclavian artery
major artery of the upper limb
6 branches
branches: one above pectoralis minor, two behind it and three below
crosses inferior border of teres major into arm= brachial artery
what is the axillary vein continuous with
why is the axillary vein important
what does it travel alongside with
what forms the axillary vein (2)
continuous with subclavian vein
major vein of the upper limb
travels alongside the axillary artery
formed by the unit of the deep veins of the arm with the basilic vein
What does the brachial plexus supply and what type of sensation
upper limbs
sensory and motor innervation
What r the 5 general structures of the brachial plexus (rugby teams don’t cover bruises)
structure of brachial plexus is split into 5 segments: roots, trunks, divisions, cords and branches
State the roots of the brachial plexus and where they r all found
C5-T1
found in the neck
State the trunks of the brachial plexus
superior trunk formed from C5 and 6
middle trunk formed from C7
inferior trunk formed from C8 and T1
Explain the division section of the brachial plexus and where does this occur
each trunk divides into an anterior and posterior division under the clavicle
State the cords of the brachial plexus and what r they formed by
lateral cord= ant of superior and middle
posterior cord= post of all trunks
medial cord= ant of inferior
State the branches of the brachial plexus and what (cords) they r formed from
musculocutaenous= from lateral cord axillary= branch of posterior median= branches combining from the lateral and medial cords radial= branch of posterior ulnar= branch of medial
Where r the branches of the brachial plexus located
in axilla
What does the axillary nerve innervate (2 muscles and skin)
innervates deltoid and teres minor and small region of the skin over the upper lateral arm
What muscles does the radial nerve innervate
innervates the triceps and all the muscles of the posterior compartment of the forearm
What does the musculocutaneous nerve innervate (3 muscles)
innervates three muscles in the anterior arm (coracobrachialis, biceps brachii and brachialis)
continues as a sensory nerve that innervates a region of skin over the forearm
What does the ulnar nerve innervate in the upper limb
innervates most of the muscles of the hand, medial digits and skin over the medial aspect of the hand
What does the medial nerve innervate
innervates most of the muscles of the anterior forearm (flexors of the wrist and digits), skin over the lateral aspect of the palm of the hand and over the lateral digits, innervates the small muscles of the thumb
What muscles r in the anterior arm (3)
three muscles: biceps brachii, brachialis and coracobrachialis
What is the anterior arm innervated by
musculocutaneous nerve
What is the one action of the 3 muscles of the anterior arm
flexors
What is the location of the biceps brachii
lies most superficially in the anterior arm
How many and what r the names of the muscle head of the biceps brachii
2: long head and the short head of biceps
Origin of short head of biceps brachii
coracoid process on scapula
Origins of the long head of biceps brachii
supraglenoid tubercle on scapula
Where and how do the muscle bellies of the head of the biceps brachii converge
converge via a common tendon on the radial tuberosity of the radius
What is the extra function of the tendons of the long head of biceps brachii
tendons of the long head pierces the capsules of the shoulder joint to help stabilise it
What r the movements of the biceps brachii
flexor: flexes elbow joint and contributed to shoulder joint flexion as it cross the shoulder joint
supinator: powerful supinators of the forearm when the elbow is flexed eg right handed person tightening a screw to the right
Location of the brachialis
lies deep to biceps
Origin, route and attachment of the brachialis
attached to the anterior aspect of the lower half of the shaft of the humerus and cross the elbow joint to insert distally upon the ulna tuberosity
function of the brachialis
powerful flexor of the elbow joint
Origin, route and attachment of the coracobrachialis
attaches proximally to the coracoid process to the scapula, crosses the shoulder joint and goes distally to the medial aspect of the middle part of the humerus
Function of the coracobrachialis
weak flexor for the shoulder joint
What is the cubital fossa
triangular shaped region anterior to the elbow joint
What r the 3 borders of the cubital fossa
lateral border: brachiordialis (posterior forearm muscle)
medial border: pronator teres (anteiroi forearm muscle)
superior border: formed by an imaginary line drawn between the medial and lateral epicondyles of the humerus
What r the 5 contents of the cubital fossa
tendon of biceps brachii, bicipital aponeurosis (fascial extension of the biceps tendon), brachial artery, median nerve, radial nerve
tendon of the biceps brachii and the cubital fossa
travels through the cubical fossa to its insertion point onto the radial tuborsity
bicipital anponeurosis and the cubital fossa
separates the superficial veins from deeper structures into the fossa (brachial artery and median nerve)
brachial artery and the cubital fossa
lies medial to the biceps tendon
bifurcates into its terminal branches (radial and ulnar arteries in the cubital fossa)
deep veins accompany the arteries
median artery and the cubital fossa
lies medial to brachial artery
travels through anterior compartment of arm and the cubital fossa to the anterior forearm and the hand
radial nerve and the cubital fossa
passes through arterial aseptic to fate cubital fossa
lies deep to brachioradialis
