Upper Arm & Shoulder Flashcards
Borders of the axilla
Apex (axillary inlet): lateral border of 1st rib, superior border of scapula, posterior border of clavicle
Lateral: inter tubercular groove of humerus
Medial: serratus anterior and thoracic wall
Anterior: pec major, pec minor, subclavius
Posterior: subscapularis, teres major, latissiumus dorsi
Contents of the axilla
Axillary artery (and branches) Axillary vein (and tributaries) Axillary lymph nodes Brachial plexus (and branches) Biceps brachii Corracobrachialis
Passageways exiting the axilla
inferior and lateral (into the upper limb)
Quadrangular space
Clavipectoral triangle
Borders of the quadrangular space
Superior: teres minor
Inferior: teres major
Lateral: neck of humerus
Medial: long head of triceps brachii
Contents of the quadrangular space
Axillary nerve
Posterior circumflex humeral artery
Borders of the clavipectoral triangle
Superior lateral: deltoid
Superior medial: clavicle
Inferior: pectoralis major
Content of the clavipectoral triangle
Cephalic vein
Medal pectoral nerve
Lateral pectoral nerve
Parts of the brachial plexus
Roots Trunks Divisions Cords Branches
Roots of the brachial plexus
C5 C6 C7 C8 T1
Trunks of the brachial plexus
Superior
Middle
Inferior
Divisions of the brachial plexus
Anterior
Posterior
Cords of the brachial plexus
Lateral
Posterior
Medial
Branches of the brachial plexus
Musculocutaneous nerve Axillary nerve Median nerve Radial nerve Ulnar nerve
Pathway of Musculocutanous nerve
Root: C5/C6/C7
Trunk: Superior/Middle
Divisions: Anterior
Cords: Lateral
Innervations of the Musculocutanous nerve
Motor: Biceps brachii, brachialis, coracobrachialis
Sensory: lateral Antebrachial cutaneous nerve
Pathway of the axillary nerve
Root: C5/C6
Trunk: Superior
Divisions: Posterior
Cords: Posterior
Innervations of the axillary nerve
Motor: deltoid, teres minor
Sensory: axillary superior lateral cutaneous nerve
Pathway of the Median nerve
Roots: C6/C7/C8/T1
Trunks: Superior, middle, inferior
Divisions: anterior
Cords: lateral, medial
Innervations of the median nerve
Forearm:
Muscular branches: FCR, PL, FDS
Ant. interosseous: FPL, FDP (lat 1/2), PQ
Sensory: palmar cutaneous nerve
Hand:
Muscular (recurrent): OP, AbPB, FPB
Digital cutaneous: Lumbricals (1&2MTC)
Sensory: thumb, 1st & 2nd digits, 1/2 of ring
Pathway of the Radial nerve
Roots: C5/C6/C7/C8/T1
Trunks: superior/middle/lateral
Divisions: posterior
Cords: posterior
Innervations of the radial nerve
Muscular branches: triceps brachii, anconeous, brachioradialis, ECRL, ECRB
Deep branch: Supinator, ED, EDM, ECU
Post. interosseous: AdPL, EPB, EPL, EIP
Sensation: dorsum of 3.5 lateral digits and hand
Pathway of the ulnar nerve
Roots: C8/T1
Trunks: Inferior
Divisions: anterior
Cords: medial
Innervations of the Ulnar nerve
Muscular branches: FCU, FDP (medial 1/2)
Hand muscles: palmaris brevis, AbDM, FDMB, ODM, AdP
Addition branches of the brachial plexus
C5-C7 roots: Long thoracic nerve
C5 root: dorsal scapular nerve
Superior trunk: suprascapular nerve, nerve to subclavius
Lateral & medial cords: lateral pectoral nerve
Medial cord: medial pectoral nerve, medial cutaneous nerve of arm, medial cutaneous nerve of forearm
Posterior cord: upper sub scapular nerve, thoracodorsal nerve, lower subscapular nerve
Muscles of the pectoral region
Pectoralis major
Pectoralis minor
Serratus anterior
Subclavius
Pectoralis Major
2 heads: clavicular/sternocostal
Origin: clavicular: medial clavicle, sternocostal: ant. surface of sternum/superior 6 costal cartilage, aponeurosis of external oblique
Insertion: inter tubercular sulcus of humerus
Innervation: lateral & medial pectoral nerves
Function: adducts and medially rotates upper limb, flexes upper limb
Pectoralis minor
Origin: 3rd-5th rubs
Insertion: coracoid process of scapula
Innervation: medial pectoral n.
Function: stabilises scapula, drawing it ant/inf against thoracic wall
Serratus Anterior
Origin: lateral aspect of 1st-8th ribs
Insertion: costal surface of medial border of scapula
Innervation: long thoracic n.
Function: rotates scapula allowing arm to be raised over 90. Holds scapula against rib cage
Subclavius
Origin: junction of 1st rib & costal cartilage
Insertion: inferior surface of middle third of clavicle
Innervation: nerve to subclavius
Function: anchors and depresses clavicle
Muscles of the shoulder region
Extrinsic:
Superficial: trapezius, latissimus dorsi
Deep: levator scapulae, rhomboid major, rhomboid minor
Intrinsic:
Deltoid, teres minor
Rotator cuff: teres major, supraspinatus, infraspinatus, subscapularis
Trapezius
Origin: skull, nuchal ligament, spinous processes C7-T12
Insertion: clavicle, acromion, scapula spine
Innervation: accessory nerve
Function: elevates scapula, retracts scapula
Latissimus Dorsi
Origin: spinous process T7-T12, iliac crest, thoracolumbar fascia, inferior 3 ribs
Insertion: intertubercular sulcus of humerus
Innervation: thoracodorsal nerve
Function: extends, adducts and medially rotates upper limb
Levator scapulae
Origin: transverse process C1-C4
Insertion: medial border or scapula
Innervation: dorsal scapular nerve
Function: elevates scapula
Rhomboid major
Origin: spinous process T2-T5
Insertion: medial border of scapula
Innervation: dorsal scapula nerve
Function: retracts and rotates scapula
Rhomboid minor
Origin: spinous process C7-T1
Insertion: medial border of scapula
Innervation: dorsal scapula n.
Function: retracts and rotates scapula
Deltoid
Can be divided into anterior, middle, posterior
Origin: lateral 1/3 of clavicle, acromion, spine of scapula
Insertion: deltoid tuberosity on lateral aspect of humerus
Innervation: axillary nerve
Function: ant: flexion/medial rotation. middle: abduction. post: extension/lateral rotation
Teres Major
Origin: posterior surface of inferior angle of scapula
Insertion: medial lip of inter tubercular groove of humerus
Innervation: lower subscapular nerve
Function: adducts and extends shoulder, medially rotates arm
Teres minor
Origin: post. surface of scapula
Insertion: greater tubercle of humerus
Innervation: axillary nerve
Function: laterally rotates arm
Suprasinatus
Origin: supraspinous fossa of scapula
Insertion: greater tubercle of humerus
Innervation: suprascapula n.
Function: abducts arm 0-15, assists deltoid 15-90
Infraspinatus
Origin: infraspinous fossa of scapula
Insertion: greater tubercle of humerus
Innervation: supra scapular n.
Function: lateral rotates arm
Subscapularis
Origin: subscapularis fossa
Insertion: lesser tubercle of humerus
Innervation: upper & lower subscapular n.
Function: medial rotation of arm
Muscle compartments of the upper arm
Anterior
Posterior
Muscles of the anterior compartment of the upper arm
Biceps Brachii
Brachialis
Coracobrachialis
Muscles of the posterior compartment of the upper arm
Triceps Brachii
Biceps Brachii
2 headed muscle.
Origin: long head: supraglenoid tubercle, short head: coracoid process
Insertion: radial tuberosity and fascia of forearm (bicipital aponeurosis)
Innervation: musculocutaneous n.
Function: supination of forearm, flexion at elbow and shoulder
Brachialis
Origin: medial and lateral surface of humeral shaft
Insertion: ulnar tuberosity
Innervation: musculocutanous n.
Function: flexion at elbow
Coracobrachialis
Origin: coracoid process
Insertion: medial side of humeral shaft
Innervation: musculocutanous n.
Function: flexion of arm at shoulder
Triceps Brachii
3 heads: medial, long, lateral Origin: long: infraglenoid tubercle. Lateral: humerus, superior to radial groove. medial: humerus, inf. to radial groove Insertion: olecranon of ulnar Innervation: radial n. Function: extension of arm at elbow
Shoulder joint
Ball and socket joint
Head of humerus and glenoid cavity of scapula
Bursae of the shoulder joint
Subacromial
Subscapular
Subcoracoid
Ligaments of the shoulder joint
Glenohumeral ligaments Coracohumeral ligament Transverse humeral ligament Coracoclavicular ligament Coracoacromial ligament
