Anatomy of the hand IN 14 QUESTIONS Kaan Yücel M.D., Ph.D 9.January.2013 Wednesday

1. ...bones of the hand ?

2. What are flexor retinaculum & carpal tunnel? The carpal tunnel formed anteriorly at wrist by a deep arch formed by carpal bones & flexor retinaculum (transverse carpal ligament) Flexor digitorum superficialis Flexor digitorum profundus Flexor pollicis longus Median nerve Pass through the carpal tunnel

3. What is extensor retinaculum (dorsal carpal ligament)? 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 abductor pollicis longus & extensor pollicis brevis extensor carpi radialis longus & extensor carpi radialis brevis extensor pollicis longus through three compartments on the lateral surface of the wrist.

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.

5. …Fibrous digital sheaths? Tendons of flexor digitorum superficialis and profundus cross the palm enter fibrous sheaths on the palmar aspect of the digits. formed by fibrous arches and cruciate (cross-shaped) ligaments hold the tendons to the bony plane prevent the tendons from bowing when the digits are flexed. are surrounded by a synovial

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.

7. Which are the intrinsic muscles of the hand? Palmaris brevis Thenar muscles Abductor pollicis brevis Abductor digiti minimi Hypothenar muscles Opponens pollicis Adductor pollicis Flexor digiti minimi Flexor pollicis brevis Lumbrical Interossei

8. …functions the intrinsic muscles of the hand? Palmar interossei adduct the thumb, index, ring, and little fingers with respect to a long axis through the middle finger Dorsal interossei major abductors of the index, middle, and ring fingers, at the metacarpophalangeal joints

Lumbricals 8. …functions the intrinsic muscles of the hand? flexing metacarpophalangeal joints extending interphalangeal joints medial two deep branch of the ulnar nerve lateral two median nerve

Palmaris brevis 8. …functions the intrinsic muscles of the hand? deepens cup of the palm by pulling on skin over the hypothenar eminence forming a distinct ridge. This may improve grip.

9. How are the intrinsic muscles innervated? All of the intrinsic muscles of the hand by deep branch of the ulnar nerve Except three thenar & two lateral lumbrical muscles by median nerve

Superficial palmar arch 10. ....arteries of the hand? Superficial palmar arch Deep palmar arch

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.

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

base of the carpal arch formed 13. ...carpal tunnel? base of the carpal arch formed medially by pisiform & hook of hamate laterally by tubercles of scaphoid & trapezium SLTP TTCH

14. ....anatomical snuffbox? lateral border tendons of abductor pollicis longus APLEPB extensor pollicis brevis medial border tendon of extensor pollicis longus

14. ....anatomical snuffbox? floor scaphoid & trapezium distal ends of the tendons of extensor carpi radialis longus extensor carpi radialis brevis