Muscles of the Upper Limb Flashcards
where does the pectoralis major originate
anterior surface of medial clavicle, anterior surface of sternum, superior 6 costal cartilages
where does the pectoralis major insert
intertubercular sulcus of the humerus
what is the function of the pectoralis major
adduct and medially rotate upper limb
what innervates the pectoralis major
lateral and medial pectoral nerves
where does the pectoralis minor originate
3rd-5th ribs
where does the pectoralis minor insert
coracoid process of the scapula
what is the function of the pectoralis minor
stabilises the scapula
what innervates the pectoralis minor
medial pectoral nerve
where does the serratus anterior originate
lateral aspect of ribs 1-8
where does the serratus anterior attach
costal surface of the medial border of the scapula
what is the function of the serratus anterior
rotate scapula, allowing arm to be raised 90 degrees. holds scapula against rib cage
what innervates the serratus anterior
long thoracic nerve
where does the deltoid originate
scapula and clavicle
where does the deltoid attach
deltoid tuberosity on the lateral surface of the humerus
what is the function of the deltoid
extend the arm at the shoulder. abduct the arm
what innervates the deltoid
axial nerve
where does the coracobrachialis originate
coracoid process of the scapula
where does the coracobrachialis attach
medial side of the humerus
what is the function of the coracobrachialis
flexion of the arm at the shoulder. adduction
what innervates the coracobrachialis
muscuolcutaneous nerve
what are extrinsic muscles of the shoulder
ones that originate from the thorax and attach to bones of the shoulder
what are intrinsic muscles of the shoulder
muscles which originate from the scapular or clavicle and attach to the humerus
where does the tere major originate from
posterior surface of the inferior angle of the scapula
where does the teres major attach
intertubercular groove of the humerus
what innervates the teres major
lower subscapular nerve
what is the action of the teres major
adducts the shoulder and medially rotates the arm
what is the collective function of the rotator cuff muscles
they pull the humerus head into the glenoid fossa and stabilise the glenohumeral joint
what 4 muscles make up the rotator cuff muscles
supraspinatus, infraspinatus, subscapularis and the teres minor
where does the supraspinatus orginate from
supraspinatus fossa of the scapula
where does the supraspinatus attach
greater tubercle of the humerus
what is the function of the supraspinatus
abducts arm 15 degrees
what innervates the supraspinatus
suprascapula nerve
where does the infraspinatus originate
infraspinatus fossa of the scapula
where does the infraspinatus attach
greater tubercle of the humerus
what is the function of the infraspinatus
laterally rotates the arm
what innervates the infraspinatus
suprascapula nerve
where does the subscapularis originate
subscapula fossa of the costal side of the scapula
where does the subscapularis attach
lesser tubercle of the humerus
what is the function of the subscapularis
medially rotates the arm
what innervates the subscapularis
upper and lower subscapula nerves
where does the teres minor originate
posterior surface of the scapula
where does the teres minor attach
greater tubercle of the humerus
what is the function of the teres minor
laterally rotate the arm
what innervated the teres minor
axillary nerve
What muscles causes the first 15 degrees in abduction
Supraspinatus
What muscle causes abduction of the arm 15-90 degrees
Deltoid
What muscle causes abduction over 90 degrees
Upper trapezius and serratus anterior
What 3 muscles causes adduction
Pectoralis major, latissimus dorsi and teres major
What muscles causes flexion (4)
Anterior fibres of the deltoid, pectoralis major, caracobrachialis, biceps brachii
What muscles causes extension (3)
Posterior deltoid fibres, latissimus dorsi and teres major
What 4 muscles causes internal rotation
Subscapularis, teres major, pectoralis major, latissimus dorsi
What 2 muscles causes external rotation
Infraspinatus and teres minor
What 2 branches come off the axillary artery and wraps around the humerus
Anterior and posterior circumflex humeral artery
What does the shoulder girdle consist of
Clavicle and scapula
What does the sternoclavicular joint connect
Clavicle and sternum
What does the acromioclavicular connect
Clavicle and acromion of the scapula
What is the joint connecting the scapula to the ribs
Scapulothoracic joint
What does the glenohumeral joint consist of
The humerus head in the glenoid cavity
What are the 2 ends of the clavicle called
Acromial and sternal end
Which end of the clavicle is flattest
Sternal end
Which joint is the most common dislocated joint
Glenohumeral
What mnemonic is used for the rotator cuff
S -supraspinatus
I - infraspinatus
T - teres minor
S - subscapularis
What is the glenoid labrum
Fibrocartilaginous rim attached to the rim of the glenoid cavity
What is the function of the glenoid labrum
Deepens the glenoid cavity giving static stability to the joint
What are the 3 glenohumeral ligaments
Superior, middle and inferior glenohumeral ligaments
What do the glenohumeral ligaments connect
Humerus and the glenoid cavity
What are the 3 extra-capsular ligaments of the shoulder
Coracohumeral ligaments, coracoacromial ligament and coracoclavicular
What is the subacromial bursa
The fluid filled spaces space between the acromion and head of the humerus for reduced friction
What is found in the space between the humerus and the acromion
Subacromial bursa, rotator cuff tendons, capsule and long head of the biceps
What causes a posterior dislocation
Electric shock or seizure which causes the muscles in the rotator cuff to contract too hard pulling the humerus out of the joint
What happens in a posterior shoulder dislocation
The humerus comes out of the socket at the back
What ligaments are broken in a dislocation of the acromioclavicular joint
Coracoclavicular ligaments
What proportion of fractures are displaced
20%
What is calcific tendinitis
Where there are calcium hydroxyapatite deposits causing the collagen tendon to ossify
What can occur if the space between the humerus and the acromion decreases
Impingement can occur
What can cause the reduction in the space between the humerus and acromion
Inflammation of the bursa and tendons
where does the biceps brachii originate
supraglenoid tubercle of the scapula (long head) and the coracoid process (short head)
where does the biceps brachii attach
radial tuberosity and the fascia of the forearm
what is the function of the biceps brachii
supination of the forearm
what innervates the biceps brachii
musculocutaeneous nerve
where does the brachialis originate
medial and lateral shaft of the humerus
where does the brachialis attach
ulna tuberosity
what iis the function of the brachialis
flexion at the elbow
what innervates the brachialis
musculocutaeneous nerve
where does the triceps brachii originate
long head from the infraglenoid tubercle and the lateral head from the humerus
where does the tricep brachii attach
olecranon of the ulna
what is the function of the triceps brachii
extension at the elbow
what innervates the triceps brachii
radial nerve
where does the Trapezius originate
skull, spinal processes C7-T12
where does the Trapezius attach
clavicle, acromion, scapula spine
what is the function of the Trapezius
elevate scapula and rotate it during abduction
what innervates the Trapezius
accessory nerve
where does the Latissimus Dorsi originate
spinal processes T6-T12, iliac crest, inferior 3 ribs and thoracolumbar fascia
where does the Latissimus Dorsi attach
intertubercle sulcus of the humerus
what is the function of the Latissimus Dorsi
extends, adducts and medially rotates
what innervates the Latissimus Dorsi
thoracodorsal nerve
where does the rhomboid major originte
spinal processes T2-T5
where does the rhomboid major attach
medial border of the scapula
what is the function of the rhomboid major
retract and rotate scapula
what innervates the rhomboid major
dorsal scapula nerve
where does the rhomboid minor originate
spinal processes C7-T1
where does the rhomboid minor attach
medial border of the scapula
what is the function of the rhomboid minor
retracts and rotate scapula
what innervates the rhomboid minor
dorsal scapula nerve
where does the Levator Scapulae originate
processes C1-C4
where does the Levator Scapulae attach
medial border to the scapula
what is the function of the Levator Scapulae
elevate the scapula
what innervates the levator scapulae
dorsal scapula nerve
What vein lies posterior to the sternoclavicular join
Braciocephalic Vein
What are the functions of the clavicle
Protect posterior nerves and blood vessels
Keep scapula in place
Attach limb to upper trunk
Provide support and free movement of the arm
Give 4 static stabiliser of the shoulder joint
- Glenoid labrum
- Glenohumeral ligament
- Extra capsular ligaments
- Negative intra-articles pressure
Give 3 dynamic stabilisers of the shoulder joint
Rotator cuff muscles
Biceps Brachii
Muscles crossing the shoulder
What is the coracocacromial arch
Formed by the coracocacrmial ligament connecting the coracoid process and the acromion
Where is the surgical neck on the humerus
The beginning of the shaft below the great and lesser tubercles
What is the significance of the anatomical neck of the humerus
Fused epiphyseal growth plates
Which nerve is mostl likely to be injured in a mid shaft break
Radial nerve as it tightly spirals around the humerus
What are the most common types of shoulder dislocation
Anterior
What nerve may be damaged in an anterior dislocation
Axillary nerve
What are the 2 causes of a posterior dislocation
Epileptic fit or electric shock
What are the six movements so fthe scapula
elevation: upper trapezius and levator scapula - moves up
Depression: lower trapezius - moves down
Upward rotation : upper and middle trapezius - up and out
Downward rotation : rhomboids - down and in
Protraction : serratus anterior (like abduction- pulls apart)
Retraction: rhomboid and middle trapezius (like adduction- brings them together)
What is painful arc
Where the tendon of the rotator cuff muscles become irritated and inflamed as thy pass through the subacromial space resulting in pain, weakness and less of movement
What is the contents of the cubita fossa
Radial nerve
Biceps tendon
Brachial artery
Median nerve
