UPPER LIMB CHAPTER 6 p726 MOORE & DALLEY CLINICALLY ORIENTED ANATOMY 5 TH EDN

UPPER LIMB SHOULDER JOINT P853 Also pp 848-852

Shoulder Joint • • • Ball and socket (synovial) jnt Designed for mobility Stability compromised – soft tissue support

Important: • • • • • • • • Articulation Joint capsule Ligaments – glenohumeral, coracohumeral Movements – F, E, MR, LR, C, Abd, Add Muscles – axioappendicular, scapulohumeral Bursae – suprascapular, subacromial Blood supply – ant, post circumflex humeral aa Innervation – suprascapular, axillary, lateral pec.

Muscles which attach the humerus to the axial skeleton 1. M deltoideus 2. M latissimus dorsi 3. M teres major 4. M coracobrachialis 5. M subscapularis 6. M supraspinatus 7. M infraspinatus 8. M teres minor

M deltoideus • • • • Origin – Ant border, lateral aspect of clavicle – – Lateral border-acromion Inf lip of spine (scapula) Insertion – Deltoid tuberosity Action – Abduction – – Flexion, medial rotation Extension, lateral rotation Nerve supply – Axillary

M latissimus dorsi • • • • Origin – Lower 6 thoracic vertebrae (spines – – – L1-L5 (spines) Iliac crest (posterior) Lower 4 ribs Insertion – Bicipital groove (humerus) Action – Extension – Medial rotation Nerve supply – Thoracodorsal nerve

M teres major • • • • Origin – Dorsum of lateral border of scapula (close to inferior angle) Insertion – Medial lip of bicipital groove Action – Adduction – Medial rotation Nerve supply – Inferior subscapular nerve

M coracobrachialis • • • • Origin – Coracoid process (apex) of scapula Insertion – Shaft of humerus (medial aspect) next to deltoid tuberosity Action – Flexor (weak) – Adductor Nerve supply – Musculo-cutaneous nerve

ROTATOR CUFF MUSCLES • Muscles which stabilize the shoulder joint – Supraspinatus – Infraspinatus – Teres minor – Subscapularis

M supraspinatus • • • • Origin – Supraspinous fossa (lateral part) of scapula Insertion – Superior facet-greater tubercle of humerus Action – Abduction Nerve supply – Suprascapular nerve

M infraspinatus • • • • Origin – Infraspinous fossa (lateral part) of scapula Insertion – Middle facet-greater tubercle of humerus Action – Extension – Lateral rotation Nerve supply – Suprascapular nerve

M teres minor • • • • Origin – Lateral border of scapula Insertion – Inferior facet-greater tubercle of humerus Action – – Adduction Lateral rotation Nerve supply – Axillary nerve

M subscapularis • • • • Origin – Subscapular fossa Insertion – Lesser tubercle of humerus Action – – Adduction Medial rotation Nerve supply – Superior subscapular nn – Inferior subscapular nn

Winging of the scapula

AXILLA

• • • • Definition of axilla: An irregular space above the armpit Anterior wall – Pectoralis major – Pectoralis minor – Clavipectoral fascia • • Pierced by bv’s & nn Ends in skin of axilla Posterior wall – Subscapularis – Latissimus dorsi – Teres major Medial wall – Serratus anterior Lateral wall – Bicipital groove

• Base – Skin of armpit • Apex – Runs upwards – Clavicle (ant) – R1 (medially) – Scapula sup border (post) • Contents – Brachial plexus – Axillary artery – Axillary vein – Lymph nodes – fat

MUSCLES OF THE UPPER ARM

Compartments • • Anterior compartment – M coracobrachialis – M biceps brachii – M brachialis Posterior compartment – M triceps brachii – M anconeus

UPPER LIMB ELBOW JOINT P860

Elbow Joint • • Hinge (synovial) jnt Designed for mobility / function

• • • • • • • • Articulation Joint capsule Ligaments Movements Muscles Bursae Blood supply Innervation Important:

Cubital Fossa

• • Inverted triangle In front of elbow Borders       Base - imaginary line - 2 epicondyles Lateral border – m. brachioradialis Medial border – m. pronator teres Roof Floor - fascia, skin, superficial nerves and blood vessels - brachialis, supinator Contents - median n., brachialis a., biceps brachii tendon

Cubital Fossa

UPPER LIMB RADIOULNAR JOINT Proximal – p863 Distal – p866

Important: Proximal Joints (pivot – synovial jnt) • • • • • • • Articulation Joint capsule Ligaments – anular lig Movements – supination, pronation Muscles – see mvmnts above Blood supply – radial, radial recurrent aa Innervation – musculocut., radial, median

Important: Distal Joints (pivot – synovial jnt) • • • • • • • Articulation Joint capsule Ligaments – anterior & posterior ligs Movements – supination, pronation Muscles – see mvmnts above Blood supply – ant, post interosseous aa Innervation – ant, post interosseous nn

Forearm

• Posterior extensor compartment  12 muscle  Radial nerve

Forearm - Compartments

Posterior Extensor Compartment

• 3 muscles run from deep to the thumb  m. abductor pollicis longus   m. extensor pollicis brevis m. extensor pollicis longus  Originate from the shafts of radius and ulna as well as interosseous membrane

Posterior Extensor Compartment

Posterior Extensor Compartment

• 3 muscles lie lateral to previous group  m. brachioradialis   m. extensor carpi radialis longus m. extensor carpi radialis brevis

Posterior Extensor Compartment

Posterior View Anterior View

Posterior Extensor Compartment

• 3 muscles lie medial to previous group  m. extensor digitorum   m. extensor digiti mini m. extensor carpi ulnaris

Posterior Extensor Compartment

Posterior View

Posterior Extensor Compartment

• 3 other muscles  m. anconeus   m. extensor indicis m. supinator

Posterior Extensor Compartment

Posterior Extensor Compartment

• Actions  Extension of wrist and fingers    m. anconeus m. supinatior – helps extension of elbow – supinates forearm m. brachioradialis – arm in neutral position it flexes the elbow joint, if hand is pronated or supinated it turns hand back to neutral position

Distal Radio-Ulnar Joints