Dr. S. Nishan Silva (MBBS) Wrist Hand and Fingers Dr. S. Nishan Silva (MBBS)

Surface Anatomy of Upper Limb Carpal Tunnel Carpals concave anteriorly Carpal ligament covers it Contains: long tendons, Median nerve Inflammation of tendons = compression of Median nerve Anatomical Snuffbox Lateral = E.pollicis brevis Medial = E. pollicis longus Floor = scaphoid, styloid of radius Contains Radial Artery (pulse) Surface Anatomy of Upper Limb Frolich, Human Anatomy,UpprLimb

Bones of the Wrist

Bones of the Wrist

Ligaments of Wrist (dorsal)

Triangular Fibrocartilage Ligament (TFCC) Triangular Fibrocartilage Ligament (TFCC) *extends from ulnar side of distal radius & attaches to ulna @ base of ulnar styloid process *disc provides stability to wrist *major stabilizer of distal radioulnar joint

Tendons of Wrist (dorsal)

Wrist (dorsal)

(dorsal)

Hand Anatomy Flexor digitorum superficialis (FDS) insert into middle phalanx. Flexor digitorum profundus (FDP) runs deep to the FDS until the level of the MP joint where FDS bifurcates. FDP inserts at the base of the distal phalanx and acts primarily to flex the DIP joint as well as all other joints flexed by FDS. (Figure 268-5).

Ligaments of Wrist (palmar)

Flexor retinaculum It is attached, medially, to the pisiform and the hamulus of the hamate bone; laterally, to the tubercle of the scaphoid, and to the medial part of the volar surface and the ridge of the trapezium.

Tendons of Wrist (palmar)

(palmar)

(palmar)

(palmar)

Bones of the Hand

Bones of the Hand

Carpal Tunnel

Joints of the Upper Extremity Radiocarpal joint Synovial-condyloid Distal radius with proximal row of carpals Intercarpal joints Synovial-plane Carpal-metacarpal (2-5) Trapezium-metacarpal 1 Synovial-saddle Metacarpal-phalangeal Interphalangeal Synovial-hinge ALL DIARTHROSES

Carpal Tunnel

Anatomy Review Muscles & Tendons Extrinsic Flexor tendons Flexor carpi ulnaris Flexor carpi radialis Palmaris longus Flexor pollicis longus (FPL) Flexor digitorum profundis (FDP) Flexor digitorum superficialis (FDS) The flexor carpi ulnaris and the flexor carpi radialis are the main flexors of the wrist and are located on the radial and ulnar side of the wrist, respectively. The palmaris longus, a rudimentary muscle that runs down the center of the forearm, inserts the palmar fascia in the palm. The remaining flexors of the hand pass beneath the transverse carpal ligament within the carpal canal and include the flexor pollicis lungus (FPL), flexor digitorum profundus (FDP), the flexor digitorum superficialis (FDS). The FPL inserts on the distal phalynx and flexes the IP joint of the thumb. Each finger, excluding the thumb, has a flexor profundus and flexor superficialis. The FDP inserts on each distal phalanx and flexes all three joints in the finger. The superficialis tendon insert on the middle phalanx and flexes the PIP.

Anatomy Review Muscles & Tendons Extrinsic Extensor tendons Abductor pollicis longus Extensor pollicis brevis Extensor carpi radialis longus and brevis Extensor digitorum Extensor digiti minimi Extensor carpi ulnaris

HAND & FINGER ANATOMY 9 Finger Flexors Median nerve Transverse carpal ligament 5 deep flexors pass through superficialis tendons and insert on distal phalanx of each finger and thumb 4 superficial flexors insert on middle phalanx of digits 2-5 Annular ligaments = pulleys (A1-A5) PREVENT BOWSTRINGING

Extrinsic Hand Muscles

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

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

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

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

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

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

Flexor Digitorum Superficialis Medial epicondyle of humerus Middle ½ anterior radius I Four tendons separating into two parts that insert into sides of bases of middle 2-5 phalanxes N Median F MCP flexion digits 2-5 PIP flexion digits 2-5

Flexor Digitorum Profundus Anteriomedial surface of ulna Interosseus membrane I Four tendons inserting into distal phalanges of digits 2-5 N Median 2-3 digits Ulna 4-5 digits F DIP flexion of 2-5 digits

Intrinsic Hand Muscles Thenar Eminance

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

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

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

Intrinsic Hand Muscles Hypothenar Eminence

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

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

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

Other Intrinsic Hand Muscles

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

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

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

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

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

Intrinsic Muscles of Hand pg 297 Palmar Interossei Dorsal Interossei Lumbricals 3rd ABduction ADDuction 2nd 4th 1st Interossei help the lumbricals to extend IP joints and flex MC-P joints

Movements

Joints Wrist joint 70 to 90 degrees of flexion 65 to 85 degrees of extension 15 to 25 degrees of abduction 25 to 40 degrees of adduction

Joints Each finger has 3 joints Metacarpophalangeal (MCP) joints Proximal interphalangeal (PIP) joints Distal interphalangeal (DIP) joints

Joints Thumb has 2 joints Metacarpophalangeal (MCP) joint Full extension into 40 to 90 degrees of flexion

Joints Thumb has 2 joints Interphalangeal (IP) joint Flex 80 to 90 degrees

Joints Thumb has 2 joints Carpometacarpal (CMC) joint of thumb Unique saddle-type joint 50 to 70 degrees of abduction Flex 15 to 45 degrees & extend 0 to 20 degrees

Thumb Movements

Movements Wrist Fingers Flexion & extension Abduction & adduction Flex & extend MCP joints also abduct & adduct

Movements Opposition Reposition movement of thumb across palmar aspect to oppose any or all of the phalanges Reposition movement of thumb as it returns to anatomical position from opposition with hand and/or fingers

Anatomy Review Muscles & Tendons Extrinsic Intrinsic Extension of MP Flex of IP Intrinsic Abduct and adduct fingers Flexion of MP Extension of IP The intrinsic muscles of the hand are the interosseous muscles, the lumbricals, and muscles of the thenar and hypothenar region. The intrinsic muscles of the hand provide the fingers with the ability to abduct and are involved with flexion at the MP joint and extension of the IP joints. The extrinsic muscles extend the MP joint and flex the IP joints. When the intrinsic system is weakened, the hand will take on an intrinsic minus posture (extension at the MP joints and flexion of the MPO joints). An intrinsic plus posture is the reverse (flexion at the MP joints and extension of the IP joints).

Hand Grips Grasps Power grip is when an object needs to be held forcefully and then moved by more proximal muscles. Precision Grip is when an object is manipulated with fingers

Hand Grips Power grips Cylindrical grip is fingers flexed around an object. Thumb on one side fingers on other, like gripping a hammer or racquet. Spherical grip is fingers and thumb are together around an object. Like grabbing an apple or doorknob.

Hand Grips Power Grip Hook grip involves the second through fifth fingers flexed around an object in a hooklike manner. Thumb is extended and not involved at all. Only possible grip for someone with no thumb or median nerve ability.

Hand Grips Precision Grips- Pad to pad Pinch grip is the thumb and one finger gripping Three jaw chuck is holding a pencil, three fingers and thumb.

Hand Grips Precision Grips Tip to Tip grip Pincer grip is tip of thumb against tip of a finger, like to pick up a coin. Difficult with long fingernails

Hand Grips Precision Grips Lumbrical grip or plate grip has the MCP and PIP joint flexed and the DIP extended. The thumb opposes and this grip is used to hold something horizontal like a plate. Lumbricals is used they flex the MCP joint.

Nerve Innervation (dorsal)

Nerve Innervation (palmar)

Intrinsic Muscles of Hand Nerve Pinky (little finger) All digiti minimi Ulnar (Flexor, Abductor, Opponens) Thumb Abductor pollicis brevis Median Flexor pollicis brevis Median Opponens pollicis Median Adductor pollicis Ulnar Other Intrinsic Muscles Palmar + Dorsal Interossei Ulnar Lumbricals Median, Ulnar

Hand Anatomy Blood supply (BS): Hand and digits has dual (BS) with contributions from the radial and ulnar arteries.

Hand Anatomy Blood supply (BS): Proximal portions of the hand (BS) come from the deep and superficial arches on the palmar and dorsal side. BS of the fingers is distributed by the digital arteries that arises from the superficial palmer arch.

Hand Anatomy - Blood supply The Allen's test.

Digital Allen Test (arterial compromise): The examiner instructs pt. to rapidly open and close the hand 15 times As soon as the athlete finishes the final repetition, the examiner places his or her thumb over the pt’s radial artery and index finger over the pt’s ulnar artery If pt’s hand remains cyanotic until after the examiner removes the pressure, then the test is positive for poor, impaired, and/or depressed perfusion (circulation) through the distal extremities

Brachial Plexus innervation

Innervation by Posterior Cord Radial Nerve (largest branch) Course: Through arm, around humerus, around lateral epicondyle, then divides Innervates: all posterior muscles of arm and forearm Triceps brachii, anconeus, supinator, brachioradialis Divides in forearm: Superficial = skin of arm and dorsolateral surface of hand Deep = extensor muscles of forearm (eg E. carpi radialis L + B) Damage to Radial Nerve = wristdrop Inability to extend the hand, st inability to fully extend forearm

Innervation by Posterior Cord (continued) Axillary Nerve (runs w/ caudal humeral circumflex a.) Innervates: Deltoid and Teres minor (motor inn) Capsule of shoulder, skin of shoulder (sensory inn) Subscapular Nerve {branches of C5 + C6 rami} Innervates: Subscapularis, Teres major Thoracodorsal Nerve (runs w/thoracodorsal a+v) Innervates: Latissimus dorsi

Innervation by Lateral Cord Musculocutaneous Course: branches to arm, distal to elbow becomes cutaneous for lateral forearm skin Innervates Biceps brachii, brachialis, coracobrachialis (motor inn) Skin distal to elbow (sensory) Suprascapular (runs w/suprascapular a+v) {C5, C6} Innervates: Supraspinatus, Infraspinatus

Innervation by both Lateral and Medial Cords Median Course: middle of brachial plexus, does not branch in arm, distal to elbow provides many branches to most forearm flexors, passes through carpal tunnel to hand to lateral palmar intrinsics Innervates: most muscles of anterior forearm (motor inn) (eg) most flexors, some intrinsics (thumb) Innervates: skin of lateral 2/3 hand on palm side, dorsum of fingers 2+3 (sensory inn) Nerve Damage = “Ape” Hand Inability to Oppose Thumb

Clinicals

Wrist drop - Radial

Ulnar claw hand

Testing Ulna nerve

Median Claw Hand

Carpal Tunnel Syndrome Entrapment of the median nerve Phalen’s and Tinel’s Test 2 point discrimination Symptoms Aching in hand and arm Nocturnal or AM paresthesias “Shaking” to obtain relief

Carpal tunnel Syndrome

Carpal tunnel Syndrome

Colles’ Fracture Most common fracture in Osteoporotic bones Extra-Articular : 1 inch of distal Radius Results from a fall on dorsi flexed wrist Typical deformity : Dinner Fork Deformity is : Impaction, dorsal displacement and angulation, radial displacement and angulation and avulsion of ulnar styloid process Management is usually conservative : MUA and forearm POP

Colles’ Fracture

Scaphoid Fractures tenuous blood supply high incidence of avascular necrosis in waist and proximal fractures often require bone grafting

Scaphoid Fracture Pathoanatomy Blood supplied from distal pole In children, 87% involve distal pole In adults, 80% involve waist

Scaphoid Bone Fractures :Treatment by compression Screw Fixation

Trigger Finger Stenosing flexor tenosynovitis Painful snap or lock Palpate nodule as digit flexed and extended

Boutonniere Deformity Tear or stretch of the central extensor tendon at PIP Note: unopposed flexion at PIP Extension at DIP Trauma or inflammatory arthritis

Swan Neck Deformity Contraction of intrinsic muscles (trauma, RA) NOTE: Extension at PIP

Mallet Finger Hyperflexion injury Ruptured terminal extensor mechanism at DIP Incomplete extension of DIP joint or extensor lag Treatment: stack splint

Dorsal Muscle Wasting

Dorsal Muscle Wasting

Rheumatoid arthritis

Rheumatoid arthritis

Summary

Muscles that move the arm (humerus) Pectoralis major Flexes, adducts and rotates arm medially. Latissimus dorsi Extends, adducts, and rotates arm medially; draws arm downward and backward. Deltoid Abducts, flexes, extends, and medially and laterally rotates arm. Subscapularis Rotates arm medially. Supraspinatus Assists deltoid muscle in abducting arm. Infraspinatus Rotates arm laterally; adducts arm. Teres major Extends arm; assists in adduction and medial rotation of arm. Teres minor Rotates arm laterally; extends and adducts arm. Coracobrachialis Flexes and adducts arm. Systematic Anatomy Dept of Anatomy, Medical College, Qingdao University

Muscles that move the forearm (radius and ulna) Biceps brachii Flexes and supinates forearm; flexes arm. Brachialis Flexes forearm. Brachioradialis Flexes forearm; semisupinates and semipronates forearm. Triceps brachii Extends forearm; extends arm. Anconeus Extends forearm. Pronator teres Pronates forearm and hand and flexes forearm. Pronator quadratus Pronates forearm and hand. Supinator Supinates forearm and hand. Systematic Anatomy Dept of Anatomy, Medical College, Qingdao University

Dept of Anatomy, Medical College, Qingdao University Muscles that move the wrist, hand, and fingers Flexor carpi radialis Flexes and abducts wrist. Palmaris longus Flexes wrist. Flexor carpi ulnaris Flexes and adducts wrist. Flexor digitorum superficialis Flexes middle phalanges of each finger. Flexor digitorum profundus Flexes distal phalanges of each Flexor pollicis longus Flexes thumb. Extensor carpi radialis longus Extends and abducts wrist. Extensor carpi radialis brevis Extends and abducts wrist. Extensor digitorum Extends phalanges. Extensor digiti minimi Extends little finger. Extensor carpi ulnaris Extends and adducts wrist. Abductor pollicis longus Extends thumb & abducts wrist. Extensor pollicis brevis Extends thumb & abducts wrist. Extensor indicis Extends index finger. Systematic Anatomy Dept of Anatomy, Medical College, Qingdao University

Muscles that move the fingers Abductor pollicis brevis Abducts thumb. Flexor pollicis brevis Flexes and adducts thumb. Opponens pollicis Draws thumb across palm to meet little finger (opposition). Adductor pollicis Adducts thumb. Abductor digiti minimi Abducts little finger. Flexor digiti minimi Flexes little finger. Opponens digiti minimi Draws little finger across palm to meet thumb. Lumbricals Extends interphalangeal joints and flexes metacarpophalangeal joints. Dorsal interossei Abducts fingers from middle finger; flexes metacarpophalangeal joints; and extends interphalangeal joints. Palmar interossei Adducts fingers toward middle finger; flexes Systematic Anatomy Dept of Anatomy, Medical College, Qingdao University