Hand and Wrist Anatomy 14 phalanges 5 metacarpals 8 carpal bones 2 sesamoid bones (thumb) 5 metacarpals 8 carpal bones Distal Radius Forms small ulnar notch to accept the ulnar head Radial styloid process Distal Ulna Ulnar styloid process arises from medial surface Ulnar head

Hand and Wrist Anatomy Carpals(flat bones aligned in 2 rows) Proximal Scaphoid-most commonly fractures Lunate-most commonly dislocated Triquetrum Pisiform-acts as sesmoid bone Distal Trapezium(aligns with 1st metacarpal) Trapezoid(2nd metacarpal) Capitate(3rd metacarpal) Hamate(4th and 5th metacarpal)

Articulations Distal Radioulnar Formed by ulnar head and ulnar notch Allows 1 degree freedom of movement Pronation/supination Radius glides around the ulna

Articulations Radiocarpal joint Reinforced by ligamentous thickening Formed by distal radius articulating with scaphoid, lunate and triangular fibrocartilage disk(TFCC) Ellipsoid joint (2 degrees freedom) Flexion/extension Radial/ulnar deviation

Articulations Intercarpal Joints Palmar/dorsal/interosseous ligaments between each carpal Very little gliding

Articulations Midcarpal Joints Proximal/distal carpal row separated by a single joint cavity with small fibrous projections connecting the rows Limited mobility in flex/ext, radial/ulnar deviation

Articulations Carpometacarpal Joint (CMC) MC1/trapezium MC2/trapezoid MC3/capitate MC4and 5/hamate (forms 1 articulation)

Articulations 1st CMC (thumb) Saddle joint 2 degrees of freedom(3) Flexion/extension Abduction/adduction Accessory rotation Allows for opposition

Articulations 2-4 CMC 5th CMC Plane/synovial joint 1 degree freedom Flexion/extension 5th CMC 2 degree freedom Abduction/adduction

Articulations Metacarpophalangeal Joint (MCP) Two degrees freedom of movement Flexion/extension Abduction/adduction Thumb can abduct at any point/fingers only when extended Collateral ligaments Varus/valgus force When fingers are in flexion they tighten and limit abduction/adduction

Articulations Interphalangeal Joint One degree freedom of movement Flexion/extension Collateral ligaments

Muscular Anatomy Wrist Extensors (innervated by radial n.) Superficial Extensor carpi radialis brevis/longus Extensor carpi ulnaris Extensor digitorium brachioradialis Deep compartment Extensor pollicus longus/brevis Abductor pollicus longus Extensor indices supinator Secured by extensor retinaculum

Muscular Anatomy Wrist flexors (median n.) Superficial Deep Flexor carpi radialis Palmaris longus Flexor carpi ulnaris Flexor digitorium superficialis Pronator teres Deep Flexor digitorium profundus Flexor pollicis longus Pronator quadratus

Muscular Anatomy Palmar (intrinsic) Thenar Abductor pollicis brevis Flexor pollicis brevis Opponens Pollicis Tendon FPL Adductor pollicis

Muscular Anatomy Hypothenar Abductor digiti minimi Opponens digiti minimi Flexor digiti minimi brevis

Muscular Anatomy Central Lumbricales Palmar aponeurosis Interossei Tendons FDS/FDP Superficialis (PIP) Profundus (DIP) Lumbricales Radial side profundus tendon(extensor hood) Flex MP/ext PIP/DIP Palmar aponeurosis Interossei 4 palmar/4 dorsal

Carpal Tunnel Fibro-osseous structure Tunnel contains 10 structures Floor is proximal carpal bones Roof is transverse carpal ligament Tunnel contains 10 structures Median n., flexor pollicis longus tendon, 4 slips of flexor digitorium superficialis, flexor digitorium profundus Compression results in paresthesia 2-4 fingers and decrease grip

Wrist and Hand Evaluation

History Location of pain Mechanism of injury Relevant sounds/sensations Duration of symptoms Description of symptoms Previous history General medical health

Inspection General Posturing of hand Gross deformity Palmar Creases Areas of lacerations or scars Wrist Continuity of distal radius and ulna Continuity of carpals/metacarpals Lunate dislocation Alignment of MCP joint Posture of wrist and hand Ganglion cyst Volkman’s Contracture Finger Deformities

Inspection Hand Alignment of knuckles Alignment of fingernails Depressed(metacarpal fracture) Alignment of fingernails Spiral fracture Boutonniere deformity Flex PIP, ext MP/DIP Mallet finger Inability to extend distal phalanx Avulsion of extensor tendon 25-35 flexion DIP Jersey Finger Ruptured FDP-inability to flex DIP

Palpation Anteromedial Ulnar head Ulnar styloid process UCL-(styloid, triquetrum and pisiform) Pisiform Triquetrum Hamate Wrist flexor group Flexor Carpi Ulnaris Flexor Digitorium Profundus Palmaris Longus Flexor carpi radialis Carpal Tunnel

Palpation Posterolateral Radial shaft Distal radius and styloid process Radial collateral ligament Scaphoid(Anatomical snuff box) Extensor Carpi Radialis Longus Extensor Digitorium Extensor Carpi Ulnaris Thumb extensors (EPL, EPB)

Palpation Bony Carpals Metacarpals Phalages Ulna Radius scaphoid Metacarpals Phalages Ulna Radius Lister’s Tubercle

Palpation Hand Collateral ligaments of MCP(1-5) Phalanges Collateral ligaments of IP joints Thenar compartment Thenar webspace Central compartment Hypothenar eminence

Wrist AROM (2 degrees) PROM RROM Ligamentous/Capsular Testing Neurologic Testing Special Tests

Wrist Goniometry Flexion and Extension Patient Fulcrum Stationary Arm Forearm pronated with hand off edge of table Fulcrum Over lateral joint line of wrist Stationary Arm Centered midline of ulnar shaft Movement Arm Centered on midline of 5th metacarpal

Radial and Ulnar Deviation Patient Forearm is pronated with hand resting on table Fulcrum Aligned with the center of distal radioulnar joint just proximal to capitate Stationary Arm Centered over midline of forearm Movement Arm Centered over 3rd metacarpal

Wrist AROM 2 degrees Sagittal plane Frontal plane (in neutral) Flexion (80-90) Extension (75-85) Fingers relaxed to ensure maximum ROM Frontal plane (in neutral) Radial (20) Ulnar deviation (35)

PROM Flexion: firm end point Extension: firm end point Radial deviation: hard (scaphoid/styloid) Ulnar deviation: firm end point

RROM Flexion/extension Radial/ulnar deviation

Finger A/P/RROM MCP joint Flexion/extension MCP (105-135) Flexion hard end feel Extension firm Abduction/adduction MCP (20-25) Abduction firm Flexion/extension IP Test each finger individually

Wrist Special Tests Valgus and Varus Test Patient Examiner Procedure Sitting with elbow flexed to 90 deg, forearm pronated Examiner One hand grips distal forearm other grasps hand across metacarpals Procedure UCL : Valgus stress is applied (radially deviated wrist) RCL: Varus stress is applied (ulnarly deviate wrist Positive Test Pain or laxity Implications

Wrist Special Tests Wrist Glide Patient Examiner Procedure Sitting, elbow flexed to 90 deg, forearm pronated Examiner One hand grasps distal radius, other grasps proximal carpal row Procedure Shear force is applied to wrist by gliding distal segment in a radial and ulnar direction and then in a volar and dorsal direction Positive Test Pain or significant change in glide Implications

Wrist Special Tests Ligamentous/capsular testing for fingers Valgus/Varus Full extension IP MCP-thumb Ulnar colateral (valgus) RCL of little finger

Wrist Special Tests Murphy’s sign Patient makes a fist If the head of the third metacarpal is level with the 2nd and 4th metacarpal, sign is positive for lunate dislocation

Wrist Special Tests Finkelstein’s test Patient Procedure Positive test Seated or standing Procedure Tucks thumb under fingers by making a fist Ulnarly deviate wrist Positive test Increased pain over radial styloid process and length of extensor pollicis brevis and abductor pollicis longus Implication deQuervian’s syndrome

Wrist Special Tests Neurologic Testing Special tests Drop wrist syndrome Inability to extend wrist (radial n.) Tinel’s sign

Wrist Special Tests Phalen’s Test Patient Procedure Positive Test Standing or seated Procedure Examiner applies overpressure during passive wrist flexion and holds for 1 minute Positive Test Tingling in distribution of median n. Implications Median Nerve Compression

Wrist Special Tests Vascular Occlusion Allen’s test