UPPER LIMB

CHAPTER 6 p726MOORE & DALLEY

CLINICALLY ORIENTED ANATOMY5TH EDN

UPPER LIMB

SHOULDER JOINTP853

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 deltoideus2. M latissimus dorsi 3. M teres major4. M coracobrachialis5. M subscapularis6. M supraspinatus7. M infraspinatus8. 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 scapulaWinging 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 JOINTP860

Elbow Joint

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

Important:

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

Cubital Fossa

• Inverted triangle • In front of elbow

Borders Base - imaginary line - 2 epicondyles Lateral border – m. brachioradialis Medial border – m. pronator teres Roof - fascia, skin, superficial nerves and blood vessels Floor - brachialis, supinator Contents - median n., brachialis a., biceps brachii

tendon

Cubital Fossa

UPPER LIMB

RADIOULNAR JOINTProximal – 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

Anterior View

Posterior 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 – helps extension of elbow m. supinatior – 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