Wrist and Hand Anatomy

Wrist and Hand Anatomy

Bone Anatomy Scapoid Lunate Triquetrium Pisiform Trapeziod Trapezium Capitate Hamate

Wrist Articulations Radiocarpal Joint Proximal portion Distal portion Most surface contact found

Articulations Midcarpal Joint Articulation between proximal and distal row of carpals Not an uninterupted joint Distal Row 2 degrees of freedom Moves as a fixed unit

Ligament Support Volar Carpal Ligaments Volar Radiocarpal Ligament Three bands Volar Ulnocarpal Ligament Scapholunate Interosseous Ligament Lunotriquetral Ligament

Ligament Support Dorsal Carpal Ligaments Dorsal Radiocarpal Ligament Dorsal Intercarpal Ligament Radial Collateral Ligament Ulnar Collateral Ligament

Triangular Fibrcartilage Complex Composition Role

Hand

Carpometacarpal (CMC) Joints of 2-52 Composition Carpal Arch

Carpometacarpal (CMC) Joints of 2-52 Composition Carpal Arch Ligament Support Transverse Carpal Ligament Dorsal and Palmar CMC Ligaments Dorsal and Palmar Metacarpal Ligaments Metacarpal Interosseous Ligaments

Carpometacarpal (CMC) Joints of 2-52 Composition Carpal Arch Ligament Support Transverse Carpal Ligament Dorsal and Palmar CMC Ligaments Dorsal and Palmar Metacarpal Ligaments Metacarpal Interosseous Ligaments Movement of CMC Joints

Metacarpophalangeal (MCP) Joints Ligament Support Capsule Volar Plate Collateral Ligaments Motions of 2-52 5 Fingers

Interphalangeal Joints of 2-52 5 Fingers Hinge Joints Motions

Thumb

CMC of Thumb Saddle Joint Ligament Support Capsule Intermetacarpal Ligament

MCP of Thumb Ligament Support IP Joint of Thumb

Extrinsic Hand Muscles

Extensor Indicis O I N F Dorsal surface lower ½ body of ulna Interosseus membrane Ulnar side of index finger s EDC tendon Radial (posterior interosseus) MCP and IP Ext of 2 nd digit

Extensor Pollicis Longus O I N F Posterior 1/3 ulna Interosseus membrane Posterior surface of base of thumb distal phalanx Radial (posterior interosseus) CMC, MCP and IP Ext of 1 st digit

Extensor Pollicis Brevis O I N F Dorsal 2/3 of radius Dorsal surface of base of proximal 1 st phalanx Radial (posterior interosseus) CMC & MCP Ext of thumb CMC ABD of thumb

Abductor Pollicis Longus O I N F Posterior distal 2/3 of ulna Posterior middle 1/3 of radius Interosseus membrane Radial side of base of 1 st metacarpal Radial (posterior interosseus) CMC ABD & Ext of thumb

Flexor Pollicis Longus O I N F Anterior middle ½ of radius Interosseus membrane Palmar surface of base of distal 1 st phalanx Median (anterior interosseus) IP Flexion of thumb

Extensor Digiti Minimi O I N F Lateral epicondyle of humerus Extensor expansion of 5 th digit Radial (posteior( interosseus) MCP and IP extension of 5 th digit

Flexor Digitorum Superficialis O I Medial epicondyle of humerus Coronoid process Middle ½ anterior radius Four tendons separating into two parts that insert into sides of bases of middle 2-52 phalanxes N Median F MCP flexion digits 2-52 PIP flexion digits 2-52

Flexor Digitorum Profundus O I N F Anteriomedial surface of ulna Interosseus membrane Four tendons inserting into distal phalanxes of digits 2-52 Media 2-32 3 digits Ulna 4-54 5 digits DIP flexion of 2-52 5 digits

Intrinsic Hand Muscles Thenar Eminance

Abductor Pollicis Brevis O I N F Scaphoid tuberosity Trapezium ridge Transverse carpal ligament Lateral base f proximal 1 st phalanx Median CMC & MCP ABD of thumb

Flexor Pollicis Brevis O I N F Superficial head trapezium Deep head trapezoid, capitate and palmar ligaments of distal carpal bones Base of prximal 1 st phalanx on radial side Extensor expansion Superficial median Deep Ulnar CMC & MCP Flexion of thumb

Opponens Pollicis O I Trapezium Transverse Carpal Ligament Radial side of 1 st metacarpal shaft N Median F Opposition

Intrinsic Hand Muscles Hypothenar Eminence

Abductor Digiti Minimi O I N F Pisiform Ulnar side base of 5 th proximal phalanx Ulnar MCP ABD of 5 th digit

Opponen Digiti Minimi O I N Hook of hamate Transverse carpal ligament Ulnar border of entire 5 th metacarpal bone Ulnar F MCP flexion & rotation of 5 th digit

Flexor Digiti Minimi O I Hamate bone Transverse carpal ligament Ulnar side of proximal 5 th phalanx N Ulnar F MCP Flexion of 5 th digit

Other Intrinsic Hand Muscles

Adductor Pollicis O I Oblique Head Capitate bone Bases of 2-32 3 metacarpals Transverse Head Proximal 2/3 of palmar surface of 3 rd metacarpal Ulnar side of base of 1 st proximal phalanx N Ulnar F CMC ADD of thumb

Palmar Interossei O I 1 st ulnar side base of 1 st metacarpal bone 2 nd ulnar side of 2 nd MC bone 3 rd radial side of 4 th MC bone 4 th radia side of 5 th MC bone Extensor expansion of 2,4 and 5 th digits N Ulnar F ADD of 1 st, 2 nd, 4 th and 5 th digits toward midline of hand

O I Dorsal Interossei 1 st lateral head ulnar side of 1 st metacarpal bone 1 st medial head radial side of 2 nd metacarpal bone 2 nd, 3 rd, 4 th space between metacarpal bones 1 st radial side 2 nd proximal phalanx 2 nd radial side of 3 rd 3 rd ilnar side of 3 rd 4 th ulnar side of 4 th N Ulnar F ABD of 2 nd, 3 rd, and 5 th finger from midline

Lumbricales O I N F Tendons of FDP Extensor expansion on dorsal aspect of each digits radial side 1 and 2 median 3 and 4 ulnar MCP flexion 2-52 5 digits DIP & PIP ext 2-52 5 digits

Palmaris Brevis O Flexor retinaculum I Palmar surface skin on ulnar side of hand N Ulnar F Wrinkles skin of hand on ulnar side

Biomechanics of Hand

Biomechanics of Finger Flexion Gliding mechanisms Retinaculae Ligaments Bursa Digital tendon sheaths Annular Pulleys A1-A5 A5 Cruciate Ligaments C1-C3 C3 Function of Pulleys

Biomechanics of Finger Extension Extensor Hood EDC tendons DI and PI tendons Lumbricales Central tendon Oblique Retinacular Ligaments Sagittal Bands Effects on MCP joints Effects on IP Joints