Posterior Forearm, Wrist And Hand Anatomy Flashcards
What type of joint is the radiocarpal joint?
Condylar synovial joint
What movements can occur at the radiocarpal joint?
Flexion + Extension
Ulnar + radial deviation
What type of joint is the Metacarpophalangeal joint and the Interphalangeal joints?
Hinge joints
What is Abduction of the fingers?
What joint does it happen at?
Midline = middle of middle finger
Thumb and finger move in opposite directions away from the midline
Happens at Metacarpophalangeal joint
What is Adduction of the fingers?
What joint does it happen at?
Midline = middle of middle finger
Thumb and finger move in same direction towards the midline
Happens at Metacarpophalangeal joint
What special movement can happen at the fingers which uses a combination of movements?
Circumduction
What nerve innervates the posterior forearm (whole posterior upper limb)?
Radial nerve
What is the function of the posterior forearm muscles?
Extensors
(Supination)
What are the 2 parts of the posterior compartment of the forearm?
Superficial
Deep
What muscles are in the superficial layer of the posterior compartment of the forearm?
3 to wrist, 2 to hand and 2 to other in superficial layer:
Extensor carpi radialis longus
Extensor carpi radialis brevis
Extensor carpi ulnaris
Extensor digitorum communis
Extensor digiti minimi
Brachioradialis
Anconeus
What is the origin and insertion of Brachioradialis?
Origin = lateral supracondylar ridge of humerus
Insertion = distal radius just proximal to Styloid process
What is the common extensor origin?
Lateral epicondyle of humerus
What is the function of Brachioradialis?
Flexes elbow
What is the origin of Extensor Carpi Radialis Brevis?
What is the origin of Extensor Carpi Radialis Longus?
ECRB = Lateral epicondyle (common extensor origin)
ECRL = supracondylar ridge of humerus
Where does Extensor Carpi Radialis Longus and Extensor Carpi Radialis Brevis insert?
Metacarpals II and III
What is the function of ECRB and ECRL?
Extension of wrist
Abduction of wrist
What is the origin and insertion of Extensor digitorum (communis)?
Origin = lateral epicondyle
Inserts = middle + distal phalanx II-V
What is the function of extensors digitorum?
Extends fingers II, III IV and V at the Metacarpophalangeal joint and Interphalangeal joint
What is the origin and insertion of Extensor digiti minimi?
Origin = lateral epicondyle
Inserts = attaches with extensor digitorum tendon and inserts into extensor hood of little finger
Where does extensor digit minimi come from?
It originates/comes off of the extensor digitorum muscle
What is the function of extensor digiti minimi?
Extends little finger
Wrist extension
What is the origin and insertion of Extensor carpi ulnaris?
Origin = lateral epicondyle
Insertion = metacarpal V
What is the function of Extensor carpi ulnaris?
Wrist extension
Wrist Adduction
What is the origin and insertion of Anconeus?
Origin = Lateral epicondyle (humerus)
Insertion = Olecranon (lateral surface of Olecranon of ulnar)
What is the function of Anconeus?
Extends + stabilises elbow joint
Abducts ulna during forearm pronation
What are all the muscles of the SUPERFICIAL posterior compartment of the forearm which originate at the common extensor origin/lateral epicondyle?
Extensor carpi radialis brevis
Extensor digitorum
Extensor digiti minimi
Extensor carpi ulnaris
Anconeus
What are the muscles of the deep layer of the Posterior forearm?
Supinator
Extensor indicis
Extensor pollicis longus
Extensor pollicis brevis
Abductor pollicis longus
What is the origin and insertion of the Supinator?
Origin = Lateral epicondyle + ulnar
Insert = radius
What is the function of Supinator?
Supination
What is the origin and insertion of Abductor pollicis longus?
Origin = interosseous membrane
Inserts = metacarpal 1
What is the action of abductor pollicis longus?
Thumb abduction
What is the origin and insertion of extensor pollicis longus?
Origin = ulnar
Inserts = distal phalanx of thumb
What is the action of extensor pollicis longus?
Extends all joints of thumb
What is the origin and insertion extensor pollicis brevis?
Origin = radius
Insertion = proximal phalanx of thumb
What is the action of extensor pollicis brevis?
Extends thumb at Metacarpophalangeal joint and Carpometacarpal joint
What is the origin and insertion of extensor indicis?
Origin = ulnar
Insertion = extensor hood of index
What is the action of extensor indicis?
Extends index finger
What are the borders of the anatomical snuff box?
Remember LBL
Extensor pollicis Longus (Border closest to digits)
Extensor pollicis Brevis (Border closest to thumb)
Abductor pollicis Longus (Border right next to extensor pollicis brevis)
