Wrist and Hand (copy)

fine, dexterity

The wrist and hand give us ____ motor control and purposeful _______ to interact with our external environment.

8

How many carpal bones are there?

5

How many metacarpal bones are there?

proximal, middle, distal

name the 3 bones that make up 4 of the phalanges

2 phalanges (proximal, distal)

How many phalange bones does the thumb have?

Lister’s Tubercle

tubercle on the posterior of the radius

• scaphoid

• lunate

• triquetrum

• pisiform

carpal bones in the proximal carpal row

• trapezium

• trapezoid

• capitate

• hamate

carpal bones in the distal carpal row

• scaphoid

• lunate

• triquetrum

• pisiform

• trapezium

• trapezoid

• capitate

• hamate

carpal bones from proximal to distal row

pisiform

carpal bone closest to the pinky

hook of the hamate

above the pisiform

anatomical snuffbox

in between the two tendons below the thumb on the posterior

20

There are more than ____ joints in the wrist and hand.

base (proximal), shaft, head (distal)

What are the three different parts of each metacarpal and each phalange?

distal radioulnar joint

joint where radius and ulna meet

radiocarpal joint

joint where radius and carpals meet

midcarpal joints

joint where the proximal and distal row of carpals meet

Carpometacarpal (CMC) joints

joint where the carpals meet the metacarpals

Metacarpophalangeal (MP) joints

joints at first knuckles (most proximal)

proximal interphalangeal (PIP) joints

joints at second knuckles (middle)

Distal interphalangeal (DIP) joints

joints at third knuckles (most distal)

• CMC joint

• MP joint

• one interphalangeal joint (IP)

What three joints does the thumb have?

structural: pivot

functional: uniaxial

movements: pronation, supination

distal radioulnar joint

(structural, functional, movements)

volar and dorsal radioulnar ligaments

supporting ligaments for the distal radioulnar joint

structural: ellipsoid

functional: biaxial

movements: flexion, extension, radial and ulnar deviation

radiocarpal joint 

radiocarpal joint

primary articulation between distal forearm and proximal carpal bones

Triangular fibrocartilage complex (TFCC)

• cushion between the distal ulna and carpals

• stability on ulnar side of wrist

structural: gliding

functional: gliding

movements: volar/dorsal gliding

Carpometacarpal (CMC) joint of the fingers

structural: ellipsoid

functional: biaxial

movements: flexion, extension, abduction, adduction

Metacarpophalangeal (MP) Joint

deep transverse metacarpal ligaments

holds joint line together so fingers aren’t too loose

• hinge

• uniaxial

• flexion, extension

interphalangeal joints

• saddle

• biaxial

• flexion, extension, abduction, adduction

Carpometacarpal (CMC) joint of the thumb

CMC joint

also known as the basilar joint

at the CMC joint of the thumb

the most common site of osteoarthritis in the hand

extrinsic muscles

origin proximal to the wrist and generate greater force

intrinsic muscles

contained entirely within the hand and are used for precise control

• Flexor carpi radialis (FCR)

• Flexor carpi ulnaris

• Palmaris longus

• Flexor digitorum superficialis

• Flexor digitorum profundus

• Flexor pollicis longus

extrinsic flexor muscles

medial epicondyle

Where do extrinsic flexor muscles originate?

lateral epicondyle

Where do extrinsic extensor muscles originate?

wrist

What does carpi mean?

Flexor Carpi Radialis

flexor muscle that is responsible for wrist flexion and radial deviation

Flexor Carpi Ulnaris

flexor muscle that is responsible for ulnar deviation and wrist flexion

Flexor Carpi Radialis and Flexor Carpi Ulnaris

What activities are used for self-feeding, writing, or hammering a nail?

Palmaris Longus

considered an extra muscle

• used for object grasp and wrist flexion

Flexor Digitorum Superficialis

muscle that flexes the fingers 

• flexes each joint it crosses (MCP and PIP)

Flexor Digitorum Superficialis

muscle that bifurcates (into a V-shape) and is used for functional grasp and pinch

Flexor Digitorum Profundus

• muscle that ends at the tips of the fingers

• for functional grasp and pinch

• flexes MCP, PIP, DIP

• deep to the FDS and goes underneath the FDS all the way to the end of the fingers

How does the FDP terminate?

FDP

What muscle is used for activities like playing racket sports or drawing?

bifurcates and terminates at the middle phalanx to flex the PIP joint

Where does FDS terminate?

Flexor Pollicis Longus

muscle that flexes all the joints of the thumb

Flexor Pollicis Longus

muscle used for activities like texting and sewing

5

Flexor tendon injuries are classified by ___ distinct zones.

Zone II (No Man’s Land)

What is the worst zone to injure in flexor tendon injuries?

Zone II

zone that includes the bifurcation of the FDS and the PIP joint

Zone III

zone that includes the metacarpals, begins just below the line of the MP joints

Zone IV

zone where the median nerve sits and where the carpal tunnel is

Zone V

zone that includes the wrist crease and below

everything distal to the IP joint, including the IP joint

What is Zone I of the thumb?

includes the MP joint

What is Zone II of thumb?

small space right above the CMC joint

What is Zone III of the thumb?

CMC joint until wrist crease

What is Zone IV of the thumb?

the rings on a fishing rod that keep the line against the rod

What can the digital pulley system be compared to?

digital pulley system

segments that hold the flexor tendons against the finger

Annular pulleys

pulleys that looks more like a tube

• there are 5 of them per finger

5

How many Annular pulleys are there per finger?

Cruciate pulleys

pulleys that look like an X; there are 3 of them per finger

Cruciate pulleys

Which pulleys can cause injury by coming apart and hanging off the bone?

flexor tendon sheath

all tendons put together

A2

Which pulley is the most important?

A1

Trigger finger is inflammation of the tendon at the ___ pulley.

Trigger Finger

leads to locking finger in a flexed position, tendon gets caught

Flexor muscles are stronger.

Which muscles are stronger? (flexors or extensors)

• Extensor Capri Radialis Longus (ECRL)

• Extensor Capri Radialis Brevis (ECRB)

• Extensor Capri Ulnaris (ECU)

• Extensor Digitorum (communis) (EDC)

• Extensor Indicis (Proprius) (EIP)

• Extensor Digiti Minimi (EDM)

• Abductor Pollicis Longus (APL)

• Extensor Pollicis Brevis (EPB)

• Extensor Pollicis Longus (EPL)

extrinsic extensor muscles

the lateral epicondyle

Where do the extensor muscles originate from?

Yes, the only difference between the two is that longus is longer and they have different attachments

Does brevis and longus do the same thing?

the second MC

Where does the ECRL terminate?

the third MC

Where does the ECRB terminate?

Extensor Capri Radialis Longus and Brevis (ECRL and ECRB)

both of these muscles extend the wrist and allow for radial deviation

the fifth MC

Where does the ECU terminate?

Extensor Capri Ulnaris (ECU)

extends wrist and allow for ulnar deviation

Extensor Digitorum (Communis) (EDC)

muscle that extends the fingers

Extensor Indicis (Proprius) (EIP)

muscle that extends the index finger

Extensor Digiti Minimi (EDM)

muscle that extends the pinky

pinky and index finger

Which two fingers have an extra tendon?

Abductor Pollicis Longus (APL)

muscle that abducts the thumb

Extensor Pollicis Brevis (EPB) and Extensor Pollicis Longus (EPL)

group of muscles that extends the thumb

sagittal bands

are located over the MP (metacarpophalangeal joints)

• keep the tendon on the knuckle

central slip

located over the PIP (proximal interphalangeal) joints

central slip

where the tendon of the EDC and the lateral bands meet

• at PIP

lateral bands

the two bands resulting from the bifurcation of the EDC; located at the PIP joint

terminal tendon

technical term for end of tendon, near DIP joints

Oblique Retinacular Ligament (ORL)

ligament that holds the central slip down and has fibers that go out to the lateral band

Boutonniere deformity

deformity caused by a rupture or laxity or the central slip

PIP = flexion

DIP = hyperextension

What position is the PIP in with Boutonniere deformity? the DIP?

swan-neck deformity

caused by rupture or laxity of the volar plate

PIP = hyperextension

DIP = flexion

What is the position of the PIP in Swan-neck deformity? DIP?

• lax PIP volar plate

• terminal tendon damage

What is associated with Swan-neck deformity?

Extensor Incidis (EIP)

What muscle is being used for pointing?

• Abductor Pollicis Longus

• Extensor Pollicis Brevis

• Extensor Pollicis Longus

What are the 3 extensors of the thumb?