Wrist and hand; upper limb blood supply & innervation

What attaches to the pisiform?

> flexor carpi ulnaris

> abductor digiti minimi

> flexor retinaculum

What does the scaphoid articulate with?

Radius

What does the lunate articulate with?

Radius

What does the triquetrium articulate with?

Articular disc of radiocarpal joint

What does the trapezium articulate with?

1st and 2nd metacarpals

What does the trapezoid articulate with?

2nd metacarpal

What does the capitate articulate with?

3rd and 4th metacarpals

What does the hamate articulate with?

4th and 5th metacarpals

What kind of joint is the wrist?

Synovial condyloid

What movements are possible at the wrist?

Flexion-extension

Radial/ulnar deviation - combined, circumduction-like

How many phalanges?

Thumb has 2, other digits have 3

What kind of joints are the carpo-metacarpal joints?

2nd-5th digits: ellipsoid synovial

> Only 4th & 5th move, enhances grip.

Thumb: saddle synovial

> Permits opposition

What kind of joints are the metacarpo-phalangeal joints?

Condylar synovial

What kind of joints are the interphalangeal joints?

Hinge synovial

What are the muscles of the thenar eminence?

> Abductor pollicis brevis

> Flexor pollicis brevis

> Adductor policis brevis

> Opponens policis

What are the muscles of the hypothenar eminence?

> Abductor digiti minimi

> Flexor digiti minimi brevis

> Opponens digiti minimi

> Palmaris brevis

What are the intrinsic muscles of the hand apart from thenar/hypothenar eminence?

> Lumbricals

> Dorsal interossei

> Palmar interossei

What do lumbicals do?

> Flex the metacarpophalangeal joint

> Extend the interphalangeal joints

What do dorsal interossei muscles do?

Between metacarpals

> Abduct the fingers

What do palmar interossei do?

> Adduct the fingers

What abducts and adducts the fingers?

ABduct - dorsal interossei

ADduct - palmar interossei

Innervation of intrinsic muscles of hands?

All are ulnar, except LOAF, which are median.

Lumbricals (radial two)

Opponens pollicis

Abductor pollicis brevis

Flexor pollicis brevis

What forms the borders of the carpal tunnel?

Floor: arch of the carpal bones

Roof: flexor retinaculum

What runs through the carpal tunnel?

4x tendons of flexor digitorum profundus

4x tendons of flexor digitorum superficialis

Tendon of flexor pollicis longus

Median nerve

So basically all the long flexors, and the median nerve.

Diagram shows left.

What side of the carpal tunnel does the median nerve run?

Lateral (thumb)

Symptoms of carpal tunnel syndrome?

Numbness of radial 3 1/2 digits

Atrophy of thenar eminence

Palmar sensation spared as branch of median nerve passes superficial to flexor retinaculum.

Treatment of carpal tunnel syndrome?

Surgical incision to the flexor retinaculum to relieve compression

What forms the anatomical snuffbox?

Medially (top): Extensor pollicis longus tendon

Laterally (bottom): Extensor pollicis brevis & abductor pollicis longus tendon

Proximal: styloid process of radius

What travels in the anatomical snuffbox?

Radial artery crosses floor obliquely, thumb-side to finger-side

Contains a branch of the radial nerve and cephalic vein

Clinical relevance of anatomical snuffbox?

Fractured scaphoid - tenderness on palpation

Palmus longus inserts into?

Palmar aponeurosis

Order of most superficial muscles in upper forearm, lateral to medial?

Pronator teres

Flexor carpi radialis

Palmaris longus

Flexor carpi ulnaris

Which of the flexors in the forearm is not always there?

Palmaris longus

Describe the motor innervation of the wrist & hand.

EXTENSORS

All radial nerve.

LONG FLEXORS

All median nerve.

Except: * flexor carpi ulnaris, * * medial two flexor digitorum profundus * (ring & little finger) - ulnar

INTRINSIC FLEXORS OF HAND

All ulnar nerve.

Except * LOAF * - median

* Radial (lateral) two lumbicals *

* Opponens pollicis *

* Abducens pollicis *

* Flexor pollicis brevis *

Describe the sensory innervation of the hand.

Dorsal - radial

Palmar, lateral 3 1/2 fingers and associated palm - median

Rest of palmar - ulnar

Where does the subclavian artery become the axillary?

Lateral border of 1st rib

Where does the axillary artery become the brachial?

Inferior border of teres major

What happens to the brachial artery and where?

Splits into radial and ulnar at distal end of cubital fossa

Path of the radial artery in the wrist/hand?

Behind the thumb, through the anatomical snuffbox, forwards to form the deep palmar arch, then joins the ulnar

Path of the ulnar artery in the wrist/hand?

Across to form the superficial palmar arch, then down to join the radial

Deep palmar arch - which artery, and what does it supply?

Radial artery

Supplies palm/deep muscles of palm

Superficial palmar arch - which artery, and what does it supply?

Ulnar artery

Supplies fingers (digital arteries)

What artery supplies extensors of the arm & forearm?

Arm - deep brachial

Forearm - interosseous

Common interosseous artery is a branch of what?

Ulnar artery

Describe venous drainage of arm

Superficial medial - basilic vein

Superficial lateral - cephalic vein

Joined at cubital fossa by median cubital vein

Deep - brachial vein, formed from radial and ulnar veins

Basilic joins with brachial in front of the teres major to form axillary

Cephalic joins axillary just inferior to the clavicle

Both then join subclavian

Lymphatic drainage runs parallel to...

Venous drainage

5 groups of axillary lymph nodes?

Lateral, central, apical, posterior, pectoral

Eight carpal bones?

scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate, hamate

What supplies the head of the humerus and where does it come from?

Posterior & anterior circumflex humeral arteries.

Branch of axillary artery.

Where does flexor digitorum profundus originate and insert?

Origin: Proximal body of ulna

Insertion: Base of distal phalanx

Where does flexor carpi radialis originate and insert?

Origin: medial epicondyle

Insertion: base of 2nd/3rd metacarpals

Where does flexor carpi ulnaris originate and insert?

Origin: medial epicondyle, body & olecranon of ulna

Insertion: Pisiform, hook of hamate, base of 5th metacarpal

Innervation of Trapezius

Spinal accessory nerve

Innervation of pectoralis major?

Pectoral nerves, branch of lateral cord of brachial plexus

Innervation of latissimus dorsi?

Thoracodorsal nerve

Innervation of serratus anterior?

Long thoracic nerve

Innervation of deltoid?

Axillary nerve

Innervation of supraspinatus?

Suprascapular nerve

Innervation of infraspinatus?

Suprascapular nerve

Innervation of teres minor?

Axillary nerve

Innervation of teres major?

Lower subscapular nerve

Innervation of subscapularis?

Upper & lower subscapular nerves

Where does flexor digitorum superficialis originate and insert?

Origin: Medial epicondyle, ulna and radius

Insertion: Middle phalanges

Where does flexor pollicis longus originate and insert?

Origin: Anterior radius & interosseous membrane

Insertion: Distal phalanx of thumb

Where does extensor digitorum originate and insert?

Origin: Lateral epicondyle

Insertion: Middle and distal phalanges

Where does extensor indicis originate and insert?

Origin: Posterior ulna & interosseous membrane

Insertion: Distal phalanx of index finger

How do the muscles of the hypothenar eminence sit?

SUPERFICIAL

Palmaris brevis

Abductor digiti minimi

Flexor digiti minimi

Opponens digiti minimi

DEEP

Difference between palmar and dorsal interossei (structure, not function)?

PALMAR:

> 3

> Smaller

> Originate from one metacarpal, medially

> Insert medially

DORSAL:

> 4

> Larger

> Originate from two metacarpals

> Insert laterally

Which proximal phalanges have palmar interossei?

2, 4, 5

Occasionally 1, rudimental

Which proximal phalanges have dorsal interossei?

3, 4, 5

Two attach at 4