Upper Limb: Pectoral and Scapular Regions Flashcards
In the anterior pectoral region, name the muscle that moves the clavicle? and the nerve that innovates it
Subclavius - Nerve to subclavius (C5, 6)
In the anterior pectoral region, name the muscle that moves the humerus? and the nerve that innovates it
Pectoralis Major - Innovated by the median (C8,T1) and the Lateral Pectoral nerve (C5,6,7)
In the anterior pectoral region, what two muscles move the scapula? and the nerve that innovates it
Pectoralis minor - Medial Pectoral (C8 and T1)
Serratus anterior - Long thoracic nerve (C5,6,7)
What are the main actions of the pectoralis major? and name its two heads
It adducts and medially rotates. Also is involved in flexion and extension.. Has a clavicular head and sternocostal head
What are the main actions of the serratus anterior?
It protracts the scapula, prevents winging of the scapula and is involved in scapular rotation (holds the scapula against the body)
What are the main actions of pectoralis minor? where does it attach?
It stabilises and depresses the scapula. Attaches from ribs 2/3/4 to the coracoid process
What are the main actions of subclavius
Stabilises and depresses the clavicle
Name the extrinsic back muscle that moves the humerus and what nerve is it supplied by
Latissimus Dorsi which is supplied the by thoracodorsal nerve (C6/7/8)
Name the three extrinsic back muscles that move the scapula
Trapezius - spinal accessory nerve (cranial nerve)
Rhomboids (major and minor) - Dorsal scapular nerve (C4/C5)
Levator scapula - Cervical nerves (C3/4) and Dorsal Scapular
Describe the action of latissimus dorsi at the GH joint
Extends, Adducts and medially rotates
What main muscle and other synergists are involved in scapular elevation?
Upper Trapezius
lev scapula and rhomboids
What main muscle and other synergists are involved in scapular depression
Not muscle but gravity, assisted by pectoralis maj +min, lat dorsi ect
What main muscle and other synergists are involved in scapular protraction
Serratus anterior
pectoralis muscles
What main muscle and other synergists are involved in scapular retraction
Middle trapezius
rhomboids
What main muscle and other synergists are involved in scapular upward rotation
Upper trapezius and serratus anterior
lower trapezius
What main muscle and other synergists are involved in scapular downward rotation
Latissimus Dorsi
lev scapula, rhomboids, pecs
Name the intrinsic shoulder muscles from the scapula to the humerus that move the GH joint and the nerve that innervates them
Deltoid - Axillary Nerve (C5,6)
Teres Major - Lower subscapular nerve (C5,C6)
Rotator cuff - SITS
Name the three functional parts of the deltoid and what action they preform
Anterior - Flexion and medial rotation
Middle - Abduction
Posterior - Extension and lateral Rotation
What is the deltopectoral groove?
A groove between the deltoid and pectorarlis major where the cephalic vein lays.
Where are the attachment sites for teres major?
The inferior angel of the scapula and the medial lip of the humerus.
Name the four rotator cuff muscles and what nerve innervates them. Look at the location of the muscles.
SITS
Supraspinatus - Suprascapular nerve (C5,C6)
Infraspinatus - Suprascapular nerve (C5,C6)
Teres Minor - Axillary nerve (C5,C6)
Subscapularis - Upper and Lower subscapular nerves (C5/6/7)
Describe the movements that each of the rotator cuff muscles help
Supraspinatus - initiates abduction (first 15 degrees)
Infraspinatus - External rotation
Teres Minor - External rotation
Subscapularis - internal rotation
Where do the rotator cuff muscles insert on the humerus?
3 On the greater tubercle - Supraspinatus (runs underneath the acromion), Infraspinatus and teres minor
1 on the lesser tubercle - subscapularis
Name the three arm muscles that cross the GH joint
Long head of biceps brachii
Coracobrachialis
Long head of tricep
Name the fascia that goes around pectoralis Major and Minor and then also the fascia then extends down the arm
Major - Pectoral fascia, beneath this you will find the fascia for;
Minor - Clavipectoral fascia
Extending down the arm - brachial Fascia
Describe the fascia of the supraspinatus and infraspinatus muscles
Each muscle has their own fascia that is very dense and is even the origin for some of the muscle fibres. If there is a break in the scapula blood can collect in this fascia giving a triangular bruise
What is the axilla?
It is the pyramidal space inferior to the glenohumeral joint but superior to the axillary fascia
Name the four walls of the axilla and what the wall is composed of and the base and apex
Anterior wall - Pectoralis major + pectoral fascia and pectoralis minor + clavipectoral fascia
Posterior wall - Scapula, subscapularis and inferiorly is teres major and lat. Dorsi
Medial Wall - Ribs 1-4 and serratus anterior
Lateral Wall - Humerus (intertubercle sulcus)
Floor of axillia - skin and axillary fascia.
Apex - cervico-axillary canal which boarders are the 1st rib, clavicle and scapule
Describe what forms the anterior and posterior fold of the axilla
Anterior Fold - Pectoralis Major
Posterior fold - Teres Major and Lat.Dorsi
What passes throught the axilla
Axillary vessels, brachial plexus (cords and branches) and axillary sheath
Name the 5 lymphatic gorups of the axilla
Lateral (humeral), Posterior (subscapular), Anterior (pectoral) which all drain to central lymphnodes which then drain to apical lymph-nodes
Name the three scapular spaces
Upper triangular (the triangular space) Quadrangular Lower triangular (triangular interval)
Name the borders and contents of the quadrangular space
Boarders - Teres Minor, Teres Major, Humerus, Long head of triceps
Contents - Posterior circumflex humeral artery, Axillary nerve and surgical neck of humerus
Name the borders of the upper triangular space (the triangular space)
Boarders - Teres Major, Teres Minor and long head of triceps
Contents - Circumflex scapular artery
Name the borders and contents of the triangular interval (lower triangular space)
Borders - Lateral head of triceps, Long head of triceps and Teres major
Contents - Radial nerve, Profunda brachii artery
