Hand Anatomy PDF

Hand Bi-Hung Peng, PhD Department of Neurobiology Bones and Joints of Wrist and Hand Carpal Bones Proximal Row (scaphoid, lunate, triquetrum and pisiform) Distal Row (trapezium, trapezoid, capitate, hamate) Palm of Hand  Surface Anatomy 1. Thenar eminence 2-4. Skin creases 5-6....

Hand Bi-Hung Peng, PhD Department of Neurobiology Bones and Joints of Wrist and Hand Carpal Bones Proximal Row (scaphoid, lunate, triquetrum and pisiform) Distal Row (trapezium, trapezoid, capitate, hamate) Palm of Hand  Surface Anatomy 1. Thenar eminence 2-4. Skin creases 5-6. Arterial arches 7-9. Hypothenar muscles and palmaris brevis 10. Hook of hamate 11. Pisiform 12-14. Wrist creases 15. Flexor carpi ulnaris 16. Palmaris longus 17. Flexor carpi radialis 18. Radial artery Movements of the Thumb Palmar Aponeurosis Dupuytren’s Contracture (palmar fascia fibromatosis)  Superficial dissections of right palm Muscles and arteries of deep palm Carpal Tunnel Median Nerve in Carpal Tunnel Carpal Tunnel Syndrome Median nerve compressed as it travels through the carpal tunnel Pain, numbness, tingling of the thumb, index, and middle finger and the radial side of the ring finger (usually at night) Long-term CTS leads to permanent damage (atrophy of tenar eminence) Predisposing factors: diabetes, obesity, pregnancy, hypothyroidism Occupational disease Initial approach: wrist splint that prevents flexion  Intrinsic Muscles Lumbricals Hypothenar Thenar (3) Median, recurrent n Adductor pollicis Ulnar deep Hypothenar (3)Ulnar deep Lumbricals (4) Interossei (7) Median, ulnar deep Ulnar deep  Intrinsic Muscles Lumbricals arising from FDP Opponens pollicis (in thenar group)  Lumbricals From flexor digitorum profundus to extensor expansions Flex MP and extend IP Median and ulnar nerve FDP  Long flexor tendons, and lumbrical muscles 2 3 1 4 Innervated by 1 & 2 – median n. 3 & 4 – ulnar n.  Interosseous muscles; Axial line 2 groups, dorsal and palmar (ventral) Palmar Interossei Adduct 2,4,5 digits Assist lumbricals Flex MP joints Extend IP joints Innervation by Ulnar n. deep br. Dorsal Axial line Interossei Abduct 2,4,5 digits Assist lumbricals to; Flex MP joints Extend IP joints Innervated by Ulnar n. deep branch Note; a common clinicial mnemonic is PAD and DAB (palmar adduct fingers, dorsal abduct fingers). Testing the Interosseus Muscles Long Tendons Synovial sheath in osseofibrous tunnel Fibrous and Synovial Sheaths Fibrous sheath Common synovial sheath Flexor retinaculum  Digital Osseofibrous Tunnels Deep (FDP) Superficial (FDS)  Extensor expansion “Hood” Insertion of Lumbrical Interosseous Extensor digitorum Together, lumbrical and interosseous flex MP and extend IP joints  Vinculum Connection between flexor tendon and phalanx bone (and vessels)  Vinculum Connection between flexor tendon and phalanx bone (and vessels) Median and Ulnar Nerves Median Ulnar Deep Branch of Ulnar Nerve Median Nerve - Recurrent Branch  Sensory distribution Median, Ulnar and Radial nerves M U R M U R Blood Vessels Allen’s Test Surface Anatomy of Arterial Arches superficial deep Surface Anatomy of Arterial Arches Superficial deep Level of extended thumb  Ulnar Artery Radial artery Superficial palmar arch Flexor pollicis brevis muscle Abductor pollicis brevis muscle (cut) Palmar carpal ligament Superficial palmar branch of radial artery Radial Artery Radial artery Deep palmar arch Superficial palmar branch of radial artery Anatomical snuffbox Lateral Wrist Extensor pollicis longus Extensor pollicis brevis Extensor carpi radialis Abductor pollicis longus longus brevis Radial artery in snuff box Radial nerve Cephalic vein (superficial br.) Radial Artery in Anatomical Snuffbox Scaphoid bone is at base of snuff box Most commonly fractured carpal bone  Wrist Injuries Colles’ Fracture - Very common in persons >50 yrs Scaphoid Fracture - common in young adults Questions?