Upper Extremity pt 3

flexion, extension, abduction, adduction, external & internal rotation, circumduction, supination, pronation, elevation, retraction 

upper extremity actions?

pectoralis major & minor, deltoid, subclavius, serratus anterior, coracobrachialis

what are the anterior pectoral girdle muscles?

pectoralis major

convergent muscle, comprises most of the anterior axillary wall and has two heads (sternal and clavicular)

sternal and clavicular

what are the two heads of the pectoralis major?

flexion (clavicle head), extension (sternocostal head), arm adduction, medial rotation of humerus, draws the scapula anteriorly and inferiorly, works with latissimus dorsi for climbing action, assists in forced inspiration

what are the functions of pectoralis major?

lattissimus dorsi

the pectoralis major works with what other muscle for the climbing action?

assists in forced inspiration

how does the pectoralis major assist in breathing?

medial clavicle, anterolateral sternum, superior 6 costal cartilages, aponeurosis of external oblique

what is the origin of pectoralis major?

intertubercular groove of humerus

what is the insertion of the pectoralis major?

medial and lateral pectoral nerve (brachial plexus)

what is the innervation of the pec major?

deep to pectoralis major

location of pectoralis minor

anterior 3-5th ribs

origin of pectoralis minor

medial pectoral nerve (C7, C8, T1), arise from brachial plexus 

innervation of pectoralis minor

protraction & depression of scapula, anterior rotation of scapula, assists in rib elevation (deep breath), stabilizes shoulder joint, maintain proper posture

actions of pectoralis minor ?

slouching/slumped posture, associated with excess sitting at the desk and also repetitive overhead motion

how does pectoralis minor tightness occur?

shortened/tightened muscle 

the pec minor tightness causes what to the muscle? 

when the pec minor is >1 cm off the table

how do we know if the pec minor is tight?

chest forward and arm back

pectoralis stretch

junction of 1st rib and costal cartilage 

origin of the subclavius?

inferior mid 1/3 of clavicle

subclavius insertion?

subclavian nerve (C5&C6 of brachial plexus)

innervation of subclavius

lifts 1st rib during respiration, stabilizes the clavicle with pectoral movement 

action of subclavius 

coracoid process of the scapula 

coracobrachialis origin 

medial mid-shaft of humerus

insertion of coracobrachialis

musculocutaneous nerve

innervation of coracobrachialis

flexion or arm at shoulder, assist in adduction of arm at the shoulder 

coracobrachialis action

lateral ribs 1-9 near midclavicular line

origin of serratus anterior

medial border of scapula

insertion of serratus anterior

long thoracic nerve (C5-C7 brachial plexus)

innervation of serratus anterior 

protraction/depression/up rotation of scapula, stabilizes scapula 

action of serratus anterior 

superficial procedures like lipoma excision, LND, mastectomy

the long throacic nerve can be injured with what procedures? — this can cause winged scapula

viral illness, MVA/trauma to shoulder, sports injury, heavy backpack, slumped posture

winged scapula can occur with what other causes?

winged scapula 

injury to the long thoracic nerve where the scapula sticks out vs lying flat on posterior thorax, rare but mild if it occurs

shoulder pain & stiff, less ROM, weak

symptoms of winged scapula?

wall pushup test

diagnosis of winged scapula?

adhesive capsulitis (frozen shoulder) 

what happens if winged scapula is untreated?

deltoid

powerful muscle covering glenohumeral joint and upper humerus

distal 1/3 of clavicle, lateral acromion border

origin of deltoid

deltoid tuberosity (lateral mid humerus) 

insertion of deltoid 

axillary nerve - brachial plexus

innervatino of deltoid

shoulder abduction,

anterior fibers = shoulder flexion, internal rotation

posterior fibers = shoulder extension, external rotation

actions of deltoid

dislocation of shoulder, proximal fracture of humersu

what happens if there is injury to the axillary nerve?

loss of lower ½ deltoid sensation, weakened deltoid (muscle wasting)

causes of injury to axillary nerve?

pectoral artery, pectoral nerves, cephalic vein

deltopectoral triangle contains what 3 things?

subclavian line placement (cephalic vein), surgical access to glenohumueral joint (spares muscles) 

deltopectoral triangle is a landmark for what 2 things?

abduction

action of supraspinatus

external rotation

action of infraspinatus

external rotation 

action of teres minor 

internal rotation

action of subscapularis

supraspinatus, infraspinatus, teres minor, subscapularis

what are the 4 rotator cuff muscles?

stabilize glenohumeral joint

what is the main function of the rotator cuff muscles?

supraspinous fossa

origin of supraspinatus

greater tubercle of humerus

insertion of supraspinatus

suprascapular nerve upper trunk of brachial plexus 

innervation of supraspinatus 

1st 30 degrees of abduction

action of supraspinatus

supraspinatus

what is the most commonly injured rotator cuff muscle?

excessive overhead activity or heavy lifting

supraspinatus injury is due to what?

impingement

supraspinatus injury has a risk of _______

age 40-60

supraspinatus occurs in what age group?

empty can test, assess strength & function 

how can we see if the supraspinatus is injured?

infraspinrous fossa

origin of infraspinatus

greater tubercle of humerus

insertion of infraspinatus

suprascapular nerve upper trunk of brachial plexus 

innervation of infraspinatus 

external rotation of arm

action of infraspinatus

infraspinous fossa & middle of lateral scapula border

origin of teres minor

greater tubercle of humerus

insertion of teres minor 

axillary nerve of brachial plexus

innervation of teres minor

external rotation of arm, helps with abduction

action of teres minor

anterior surface of scapula in subscapular fossa 

subscapularis location

medial 2/3 of anterior scapula

origin of subscapularis

lesser tubercle of humerus

insertion of subscapularis

upper & lower subscapular nerves from posterior cord of brachial plexus 

innervation subscapularis 

internal rotation of arm

subsapcularis action

no

is teres major a rotator cuff muscle?

dorasal, lower 1/3 of lateral border of scapula 

origin of teres major 

intertubercular groove of humerus

insertion of teres major

with latissimus dorsi, adduction of arm, helps with extension of arm

action of teres major

lateral head of triceps brachii (medial), humerus (lateral), teres minor (superior), teres major (inferior)

4 borders of the quadrilateral (quadrangular space) 

axillary nerve (sensation to lateral shoulder, innervates deltoid, teres minor), posterior circumflex humeral artery (blood to eres minor/major, triceps)

what are the contents of the quadrilateral (quadrangular space)?

brachium & antebrachium muscles

anterior and posterior compartments, deep investing fascia surrounds muscles

divided by humerus and 2 intermuscular septa 

describe the compartments of the arm 

divided by radius, ulna, interosseous membrane

describe the compartments of the forearm