WRIST AND HANDPART OF THE HAND

BONES OF THE HAND

CARPAL BONES

INTRINSIC MUSCLES

THENAR MUSCLES OF THE HAND

HYPOTHENAR MUSCLES OF THE HAND

EXTRINSIC MUSCLES OF THE HAND- Muscles from the forearm inserting on wrist and handEXTRINSIC MUSCLES: ANTERIOR COMPARTMENT

EXTRINSIC MUSCLES: LATERAL COMPARTMENT

EXTRINSIC MUSCLES: POSTERIOR COMPARTMENT

WRIST: ANTERIOR ASPECT• Superficial to the Flexor Retinaculum

(medial to lateral)• FCU tendon• Ulnar nerve• Ulnar artery• Palmar cutaneous branch of

ulnar nerve• Palmaris longus tendon• Palmar cutaneous branch of

median nerve• Passing below the Flexor Retinaculum

(medial to lateral)• FDS tendons (4) and FDP tendons (4) – common sheath• Median nerve

• Flexor pollicis longus tendon• Flexor carpi radialis (thru a split in the retinaculum)

WRIST: POSTERIOR ASPECT• Superficial to the Extensor Retinaculum

• Dorsal cutaneous branch of the ulnar nerve• Basilic vein• Cephalic vein• Superficial branch of radial nerve

• Beneath the Extensor Retinaculum• ECU tendon• EDM tendon• Extensor digitorum and Extensor indicis tendons – common sheath• Extensor pollicis longus tendon• Extensor carpi radialis longus• Abductor pollicis longus and extensor pollicis brevis

LONG FLEXOR TENDONS

LONG EXTENSOR TENDONS• Fan out from external

retinaculum• Together with deep fascia,

they form the subfascial space.

• Tendons of middle, ring and small fingers are connected by fibrous bands.

• Tendon to the index finger is joined medially by the extensor indicis.

• Extensor digiti minimi lies medial to the extensor digitorum tendon to small finger.• On the finger, extensor expansions join the tendon.• Near the PIP joint, it splits into

three, Central tendon inserts on the base of middle phalanx. The two lateral slips insert at the base of distal phalanx.

• The dorsal extensors also receive the interosseous tendons and lumbrical tendons.

VASCULAR SUPPLY TO THE HAND

PALMAR ARCHES

RADIAL ARTERY AT THE PALM• Leaves the dorsum between 1st and 2nd metacarpals.• Continues as deep palmar arch between oblique and

transverse head of adductor pollicis• Curves medially between the long flexors and interosseous

muscles to form the deep palmar arch• Has anastomosis at the wrist joint and also digital branches of

the superficial palmar arch• Branches

Arteria radialis indicis – lateral side of index finger Arteria princeps pollicis – lateral and medial sides of

the thumb

RADIAL ARTERY OF THE DORSUM

• From the lateral side of the wrist• Beneath the extensor pollicis tendon to reach the interval between first and 2nd interossei.• Branches take part of the anastomosis around the wrist• Digital arteries to the thumb and index fingers

DORSAL VENOUS ARCH• Lies on the subcutaneous tissue proximal to MCP• Drains on the cephalic and basilic veins

NERVE SUPPLY TO THE HAND MEDIAN NERVE AT THE PALM

• Starts at the fusion of the medial and lateral cords• Continues down the arm initially on the lateral side of the brachial artery then crosses over it to

lie medial to it.• Continues down in the cubital fossa• In the forearm, the nerve travels between the flexor digitorum profundus and flexor digitorum

superficialis muscles. • Enters the carpal tunnel• Palmar cutaneous branch branches out before

the retinaculum and supplies the lateral part of the palm

• After the carpal tunnel, it divided into medial and lateral branches

• Muscular branch – recurrent course to about one fingerbreadth distal to the scaphoid tubercle and supply the abductor pollicis brevis, flexor pollicis brevis and opponens pollicis and the 1st lumbricals

• Cutaneous branch to the lateral three and half digits and 2nd lumbricals

ULNAR NERVE OF THE PALM• Superficial branch

Between pisiform and hook of hamate Ulnar artery is on the lateral side Passes thru the tunnel of Guyon with the artery Muscular branch to palmaris brevis Cutaneous branch to medial one and half

fingers• Deep branch

Between abductor digiti minimi and flexor digiti minimi

Muscular branches to abductor digiti minimi, flexor digiti minimi opponens digiti minimi interossei muscles 3rd and 4th lumbricals both heads of the adductor pollicis

Palmar cutaneous branch – medial part of the palm

RADIAL NERVE COURSE• Deep branch of the Radial Nerve

Arise from radial nerve in front of the lateral epicondyle Winds around the lateral aspect of the neck Descends between the superficial and deep groups of muscles Branches

Muscular – ECRB, supinator, Extensor digitorum, extensor digiti minimi, ECU, Abductor pollicis longus, Extensor pollicis brevis and longus, and extensor indicis

Articular branch to the wrist and carpal bones RADIAL NERVE

• Enters the snuff box then supplies the lateral half of the dorsum and dorsum of the lateral 3 and half fingers up to the middle phalanx

PALMAR INNERVATIONS

DORSUM OF HAND• Sensory nerve supply: • Superficial branch of the radial nerve

Supplies the lateral 2/3 of the dorsum Supplies the lateral 3 and half fingers

• Posterior cutaneous branch of the ulnar nerve Supplies the medial third of the dorsum Supplies the medial 1 and half fingers

• Dorsal digital nerves never extend beyond the proximal phalanx.DORSAL INNERVATIONS

FASCIAL SPACES OF THE HAND

• Potential space with loose connective tissues• Limits the spread of infection• Thenar space

separated by second septum from mid palmar space Contains 1st lumbrical muscle and posterior to long flexor tendons of index finger and in

front of adductor pollicis muscle• Mid palmar space

Contains 2nd, 3rd and 4th lumbricals Posterior to long flexors of middle, ring and little fingers In front of interossei and 3rd 4th and 5th metacarpal bones

• Lumbrical canal – surrounds each lumbrical muscle and continuous with one of the palmar spaces.

PALM OF THE HAND: SKIN• Palmaris brevis

From flexor retinaculum and palmar aponeurosis to skin of the palm

Nerve: superficial branch of the ulnar nerve Action: corrugate the skin at the base of the

hypothenar eminence thus improving the grip• Sensory supply

Palmar cutaneous branch of median nerve Palmar cutaneous branch of ulnar nerve Thenar eminence – lateral cutaneous nerve of the

forearm or superficial branch of radial nerve

PALM OF THE HAND: PALMAR APONEUROSIS

• Triangular, at the center of palm• Apex attached to distal border of the palmaris longus• Base divides the base of finger (four slips)• Each slip has two bands, one passing superficial to the skin, the other deep to the root of the

finger• Deep band divides into two around the flexor tendons and fuse with the fibrous flexor sheath

and deep transverse ligaments.• Medial and lateral borders are continuous with the thenar and hypothenar muscle fascias• Function: firm attachment of the skin, improve grip and protect the tendons

CARPAL TUNNEL• Concave anterior carpal surface• Converted to tunnel by flexor

retinaculum• Contents: FPL, FDS (4), and FDP tendons

(4) and Median nerve• FS and FDP tendons have common

synovial sheath form lateral side

SYNOVIAL FLEXOR SHEATH• Starts at the lateral side• Small finger: continues distally without interruption• Ring middle and index fingers: ends at the middle of the

palm. Digital synovial sheath for the phalanges.• Thumb: FPL has its own sheath (in 50% of pop, they

communicate with FDS and FDP sheath

FIBROUS FLEXOR SHEATH• From head of metacarpal to distal phalanx• Open proximal end, closed distal end(base of distal phalanx)• Thumb: FPL tendon• Fingers: FDS and FDP tendons

JOINTS OF THE WRIST AND HAND DISTAL RADIOULNAR JOINT

• Articulation: between round head of ulna to ulnar notch of the radius• Synovial pivot joint

• Enclosed in capsule• Ligaments: anterior and posterior ligaments• Articular disc: triangular with apex at the styloid process and base at the lower border of the

ulnar notch• With synovial membrane• Nerve supply: Anterior interosseus nerve and deep branch of the radial nerve• Pronation – pronator teres and pronator quadratus• Supination – biceps brachii and supinator

More powerful than pronation• Relations:

Anterior: tendons of FDP Posterior: tendons of extensor digiti minimi.

WRIST JOINT- RADIOCARPAL• Between the distal end of the radius and articular disc above and scaphoid, lunate and triquetral

bone• Synovial ellipsoid joint

Proximal is ellipsoid concave and distal surface is ellipsoid convex.• With capsule – distal end of radius to proximal carpus• Ligaments – Anterior and posterior ligaments• Medial ligaments attached to ulnar styloid and triquetral bones• Lateral ligaments from radial styloid to scaphoid bones• With Synovial membrane• Nerve supply – Anterior interosseous nerve and deep branches of the radial nerve.• Flexion – FCR, FCU and palmaris longus• Extension – ECRL, ECRB, ECU. Assisted by Extensor digitorum, Extensor indicis, extensor digiti

minimi and EPL• Abduction (radial deviation) – FCR and ECRL and ECRB. Assisted by Abductor pollicis longus and

extensor pollicis longus and brevis• Adduction (ulnar deviation) – FCU and ECU

CMC AND INTERCARPAL JOINTS• Synovial plain joints • Common joint cavity• CMC of the thumb

Between the trapezium and base Synovial saddle shaped Encapsulated

MCP JOINTS• Head of metacarpal and base of proximal phalanx• Synovial condyloid• Encapsulated• Ligaments:

Palmar ligaments 2nd to 5th joints joined together by deep

transverse metacarpal ligament Collateral ligament at the sides of the joint

Taut in flexion and lax in extension• Flexion – lumbricals and interossei assisted by FDS and FDP• Extension – ED and EI and EDM• Abduction – dorsal interossei• Adduction – palmar interossei• Thumb MCP is only Flexion-extension

INTERPHALANGEAL JOINTS• Distal interphalangeal joint

Between Distal phalanx and middle phalanx• Proximal interphalangeal joints

Between middle phalanx and proximal phalanx• Thumb has one interphalangeal joint• Index, middle, ring and small fingers

Flexion DIP – flexor digitorum profundus PIP – flexor digitorum profundus, flexor digitorum superficialis

Extension Extensor digitorum Extensor indicis proprius• Thumb

Flexion – Flexor pollicis longus Extension – extensor pollicis longus

IMPORTANT STRUCTURES AROUND THE WRIST- SURFACE ANATOMY VOLAR SURFACE

• Radial Artery Distal third of the radius lateral to the flexor carpi radialis

• Tendon of Flexor Carpi Radialis• Tendon of Palmaris Longus• Tendon of Flexor Digitorum Superficialis• Tendon of Flexor Carpi Ulnaris• Ulnar Artery• Ulnar Nerve

LATERAL STRUCTURES Anatomic Snuffbox

• Medial border Extensor Pollicis Longus

• Lateral border Extensor Pollicis brevis Abductor Pollicis longus

• Floor Radial styloid Scaphoid Trapezium 1st metacarpal

• Contents Radial Artery Superficial branch of radial nerve Cephalic vein

DORSUM Lunate

FUNCTIONAL POSITION OF THE HAND• Semiprone• Wrist more extended than at rest• All finger flexed at the same degree• Index and thumb in apposition

MOVEMENTS OF THE HAND

CLINICAL CONDITIONSCOMPARTMENT SYNDROMES

• Carpal tunnel syndrome

• Dupuytren's disease/ dequervain

• Trigger fingers

• Tenosynovitis

FRACTURES• Distal Radius Fractures

Smith’s Fracture Colles' Fracture Barton’s Fracture

• Carpal Bone fractures

Scaphoid

• Metacarpal fracturesBase of Metacarpal

Metacarpal Shaft

• Phalangeal fractures

DEFORMITIES• Heberden's Nodes

Distal interphalangeal joints• Bouchard’s Nodes

Proximal interphalangeal joints• Mallet Deformity

• Boutonniere’s Deformity Rupture of the extensor central slip Volar displacement of the lateral slips

Changes the direction of the pull from PIP extension to PIP flexion

Lateral slips still functions as DIP extensor

NERVE INJURIES

Ulnar Nerve• Motor - Intrinsic muscles of the hand• Sensory – Medial 1 and half fingers

Median Nerve (Ape hand deformity)• Motor – Thenar Muscles, 1ST and 2ND Lumbricals• Sensory – Lateral 3 and half fingers

Radial Nerve• Motor - none• Sensory – lateral dorsum of the hand