1Kaan Yücel M.D., Ph.D 9.January.2013 Wednesday

ANATOMY OF THE HAND

IN 14 QUESTIONS

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1. ...bones of the hand ?

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2. What are flexor retinaculum & carpal tunnel?The carpal tunnel formed anteriorly at wrist by a deep arch formed bycarpal bones & flexor retinaculum (transverse carpal ligament)

Flexor digitorum superficialisFlexor digitorum profundusFlexor pollicis longus Median nerve

Pass through the carpal tunnel

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3. What is extensor retinaculum (dorsal carpal ligament)?

abductor pollicis longus & extensor pollicis brevisextensor carpi radialis longus & extensor carpi radialis brevisextensor pollicis longus

through three compartments on the lateral surface of the wrist.

The extensor tendons pass into the hand in six compartments defined by an extensor retinaculum:

extensor digitorum & extensor indicis posterior surface of the wrist

extensor carpi ulnaris & extensor digiti minimi medial side of the wrist

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4. What is palmar aponeurosis?A triangular condensation of deep fascia that covers the palm and is anchored to the skin in distal regions.

Continuous with the palmaris longus tendon, when present; otherwise, anchored to the flexor retinaculum.

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5. …Fibrous digital sheaths?Tendons of flexor digitorum superficialis and profundus cross the palm enter fibrous sheaths on the palmar aspect of the digits.

o formed by fibrous arches and cruciate (cross-shaped) ligaments

o hold the tendons to the bony plane

o prevent the tendons from bowing

when the digits are flexed. are surrounded by a synovial

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6. What are extensor hoods for?Tendons of the extensor digitorum extensor pollicis longus muscles expand over the proximal phalanges to form "extensor hoods" or "dorsal digital expansions".

Tendons of the extensor digiti minimi, extensor indicis, extensor pollicis brevis join these hoods.

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7. Which are the intrinsic muscles of the hand?Palmaris brevis

Interossei

Thenar muscles

Hypothenar muscles

Adductor pollicis

Lumbrical

Abductor pollicis brevis

Flexor pollicis brevis

Opponenspollicis

Abductordigiti minimi

Flexordigiti minimi

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8. …functions the intrinsic muscles of the hand?

Palmar interosseiadduct the thumb, index, ring, and little fingers with respect to a long axis through the middle finger

Dorsal interosseimajor abductors of the index, middle, and ring fingers, at the metacarpophalangeal joints

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8. …functions the intrinsic muscles of the hand?

Lumbricals

flexing metacarpophalangeal joints

extending interphalangeal joints

medial two deep branch of the ulnar nerve lateral two median nerve

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8. …functions the intrinsic muscles of the hand?

Palmaris brevis

deepens cup of the palm by pulling on skin over the hypothenar eminence forming a distinct ridge.

This may improve grip.

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9. How are the intrinsic muscles innervated?All of the intrinsic muscles of the hand by deep branch of the ulnar nerve

Exceptthree thenar & two lateral lumbrical musclesby median nerve

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10. ....arteries of the hand?

Superficial palmar archDeep palmar arch

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11....veins of the hand?Cephalic vein originates from lateral side of dorsal venous network. Basilic vein originates from medial side of dorsal venous network.

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12. ...sensory innervation of the hand?

Ulnar nerve medial side of the palm, medial half of the dorsum of the hand, the 5th finger, and the medial half of the 4th finger, anterior surfaces of the medial one and a half digits,Median nerve thumb,index,middle fingers,lateral side of the ring [distal parts on the dorsum of the hand]Radial nerve dorsolateral side

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13. ...carpal tunnel?base of the carpal arch

formed medially by pisiform & hook of hamate

laterally by tubercles of scaphoid & trapezium

SLTP

TTCH

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14. ....anatomical snuffbox?

lateral border tendons of abductor pollicis longus APLEPBextensor pollicis brevismedial border tendon of extensor pollicis longus

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14. ....anatomical snuffbox?floor

scaphoid & trapeziumdistal ends of the tendons of extensor carpi radialis longus extensor carpi radialis brevis