Wrist

Palmar

palm of hand

Ventral

Anterior

Dorsal

Posterior

Volar

Refers to the palm of the hand

Radiocarpal Joint

articulation between the concave distal end of the radius (proximally) and the convex scaphoid, lunate and triquetrum bones (distally); allows for flexion, extension, radial deviation and ulnar deviation

Midcarpal Joint (AKA intercarpal joint)

articulation between proximal and distal rows of carpal bones; collectively contribute and support the motion occurring at the radiocarpal joint

Wrist

10 bones (radius, ulna, 8 carpal bones); 2 joints (radiocarpal joint and midcarpal joint)

Carpal bones

proximal row (from lateral to medial) (starting at the thumb) = scaphoid, lunate, triquetrum, pisiform;

distal row (from lateral to medial) (starting at the thumb) = trapezium, trapezoid, capitate, hamate

Hook of hamate

Projection on the anterior surface of the hamate, providing attachment for the transverse carpal ligament.

hand bones

5 metacarpals, 5 proximal phalanges, 4 middle phalanges, and 5 distal phalanges

metacarpals

hand bones located in the palm of the hand; base = proximal end; head = distal end

proximal phalanges

finger bones just distal to the metacarpals; base = proximal end; head = distal end

middle phalanges

finger bones just distal to the proximal phalanges; base = proximal end; head = distal end; only 4 of them (the thumb does not have a middle phalanx)

distal phalanges

finger bones just distal to the middle phalanges; base = proximal end; head = distal end

intrinsic ligaments

proximal and distal attachments are located within the carpal bones

extrinsic ligaments

originate proximally outside of the carpal bones and attach distally within the carpal bones

dorsal radiocarpal ligament

on posterior wrist; from radius to carpal bones; limits wrist flexion

radial collateral ligament

on lateral aspect of wrist; between radius and carpal bones; limits ulnar deviation

palmar radiocarpal ligament

on palmar aspect of wrist; between radius and carpal bones; limits wrist extension

ulnar collateral ligament

on medial (ulnar) aspect of wrist; between ulna and carpal bones; limits radial deviation

flexor retinaculum

anterior wrist ligament that holds wrist flexor tendons close to the wrist when the wrist flexes

extensor retinaculum

posterior wrist ligament that holds the wrist extensor tendons close to the wrist when the wrist extends

anterior wrist muscles

FCU, FCR, Palmaris Longus

posterior wrist muscles

ECRL, ECRB, ECU

wrist flexion prime movers

FCR, FCU

wrist extension prime movers

ECRL, ECRB, ECU

radial deviation prime movers

FCR, ECRL

ulnar deviation prime movers

FCU, ECU

Flexor Carpi Ulnaris (FCU) action

Function: flexion of wrist and ulnar deviation*

*It performs ulnar deviation when it contract simultaneously with ECU

Flexor Carpi Ulnaris (FCU) innervation

ulnar nerve

Flexor Carpi Ulnaris (FCU) location

originates on medial epicondyle of humerus; inserts on the base of the 5th metacarpal and palmar aspect of pisiform

Flexor Carpi Radialis (FCR) Action

Function: flexion of wrist and radial deviation*

*It performs radial deviation when it contract simultaneously with ECRL

Flexor Carpi Radialis (FCR) Innervation

median nerve

Flexor Carpi Radialis (FCR) Location

originates on medial epicondyle of humerus; inserts on the base of the 2nd metacarpal (palmar aspect)

Palmaris Longus Action

Wrist flexion

Palmaris Longus Innervation

median nerve

Palmaris Longus Location

originates on medial epicondyle of humerus; inserts on the transverse carpal ligament and palmar fascia

Extensor Carpi Radialis Brevis (ECRB) Action

wrist extension

Extensor Carpi Radialis Brevis (ECRB) Innervation

radial nerve

Extensor Carpi Radialis Brevis (ECRB) Location

originates on lateral epicondyle of humerus; inserts on the base of the 3rd metacarpal (dorsal aspect)

Extensor Carpi Radialis Longus (ECRL) action

Function: extension of wrist and radial deviation*

*It performs radial deviation when it contract simultaneously with FCR

Extensor Carpi Radialis Longus (ECRL) innervation

radial nerve

Extensor Carpi Radialis Longus (ECRL) location

originates on lateral epicondyle of humerus; inserts on the base of the 2nd metacarpal (dorsal aspect)

Extensor Carpi Ulnaris (ECU) action

Function: extension of wrist and ulnar deviation*

*It performs ulnar deviation when it contract simultaneously with FCU

Extensor Carpi Ulnaris (ECU) innervation

radial nerve

Extensor Carpi Ulnaris (ECU) location

originates on lateral epicondyle of humerus; inserts on the base of the 5th metacarpal (dorsal aspect)