Forearm/Wrist/Hand Flashcards
Palmar carpal ligament
Most superficial ligament across the “wrist”
Is continuous with the extensor reticulum
Transverse carpal ligament
(Flexor retinaculum) deep to palmar carpal ligament
Attaches to tubercles of scaphoid and trapezium and hook of hamate/pisiform
Forms the carpal tunnel
Extensor retinaculum
Dorsal “wrist”, forms the 6 separate tunnels for the extensor/abductor tendons
Is fairly snug to wrist bones
Thenar compartments
Contains muscles that move the thumb
Adductor pollicis compartment
Separate space deep to thenar compartment (thin fascia)
Hypothenar compartment
Contains muscles that move the pinky
Central (midpalmar) compartment
Between thenar/hypothenar compartments, deep to palmar aponeurosis
Contains flexor tendons/synovial sheaths/lumbricals/ superficial palmar arch
Superficial layer of muscles in posterior of forearm
1) Brachoradialis 2&3) Extensor carpi radialis longus/brevis 4) Extensor digitorum 5) Extensor digiti minimi 6) Extensor carpi ulnar
Common extensor tendon
Extensor— carpi radialis brevis, digiti minimi, carpi ulnaris
Brachoradialis
O: supracondylar ridge
Passes anterior to elbow joint, inserts on radius
A: elbow flexion
Extensor Carpi radialis longus
O: Supracondylar ridge
I: base of index finger metacarpal
A: extends/abducts wrist
Extensor Carpi radialis brevis
I: base of middle finger metacarpal
A: extends/abducts wrist
Intertendinous connections
Link adjacent tendons to MP joint
Unable to fully isolate digits 2-5 when extensor digitorum is sole mover
Extensor expansion
Flattening/widening of extensor digitorm tendons as passes MP joint
Extensor digiti minimi
I: separate tendon to little finger hood
A: extends all little finger joints
Extensor carpi ulnaris
I: base of pinky metacarpal base
A: extends/adducts wrist
Tennis elbow
Inflammation in ECRB due to repetitive wrist stabilization while forcefully extending the elbow
Deep layers of the posterior forearm
1)Supinator 2)Extensor indicis 3)Abductor pollicis longus 4&5) Extensor pollicis longus/brevis
Supinator
O: lateral epicondyle of humerus
I: upper part of radius
A: Supination
Deep branch of radial nerve passes deep to it
Extensor indicis
O: lower part of ulna
I: tendon joints extensor digitorum to index finger
A: extends all index joints
Abductor pollicis longus
O: Interosseous area
I: base of thumb metacarpal
A: abducts/helps extend CMC joint of thumb
Extensor pollicis longus
O: Interosseous membrane/ulna
I: around the dorsal radial tubercle and into the base od the distal phalanx of thumb
A: extends all joints of the thumb
Extensor pollicis brevis
O: interosseous membrane/radius
I: Base of proximal phalanx of thumb
A: Extends CMC/MP of thumb
Anatomical snuff box
Area between tendons of extensor policies brevis/longus
Radial artery passes through the floor of this box (Scaphoid bone)
