The wrist and hand Flashcards
Name three muscles in the thenar compartment
- Abductor Pollicis Brevis
- Opponens Pollicis
- Flexor Pollicis Brevis
What is the origin, insertion, action and innervation of Abductor Pollicis Brevis
Origin: Flexor retinaculum, scaphoid, trapezium
Insertion: lateral side of proximal phalanx of the thumb
Action: abducts the thumb
Innervation: median nerve
What is the origin, insertion, action and innervation of Opponens Pollicis
Origin: Flexor retinaculum, scaphoid, trapezium
Insertion: 1st metacarpal
Action: draws 1st metacarpal to oppose the pinky in the center of the palm
Innervation: median
What is the origin, insertion, action and innervation of Flexor Pollicis Brevis
Origin: Flexor retinaculum, scaphoid, trapezium
Insertion: lateral side of proximal phalanx of the thumb
Action: flexes thumb
Innervation: median and ulnar
Name the 3 muscles in the hypothenar compartment
- Abductor Digiti Minimi
- Opponen Digiti Minimi
- Flexor Digiti Minimi
What is the origin, insertion, action and innervation of Abductor Digiti Minimi
Origin: pisiform
Insertion: medial side of the proximal phalanx of the pinky
Action: abducts the pinky
Innervation: ulnar nerve
What is the origin, insertion, action and innervation of Opponen Digiti Minimi
Origin: flexor retinaculum and hook of hamate
Insertion: medial 5th metacarpal
Action: draws 5th metacarpal to oppose the thumb in the center of the palm
Innervation: ulnar nerve
What is the origin, insertion, action and innervation of Flexor Digiti Minimi Brevis
Origin: flexor retinaculum and hook of hamate
Insertion: medial side of the proximal phalanx of the pinky
Action: flexes pinky
Innervation: ulnar nerve
Name the 2 interossei muscles and describe there origin, insertion, function and innervation
Palmer and Dorsal interossei
Origin: palmar or dorsal metacarpals
Insertion: digits 2-5
Action: adducts digits like Spock hands when he says live long and prosper
Innervation: ulnar nerve
What is the origin, insertion, action and innervation of Lumbricals
found inbetween the metacarpals
Origin: distal portion of flexor digitorum profundus tendons
Insertion: distal portion of extensor digitorum tendons
Action: flexes and extends fingers
Innervation: median and ulnar nerves
What is the origin, insertion, action and innervation of Adductor Pollicis
Origin: anterior side of 2nd and 3rd metacarpals
Insertion: medial side of proximal phalanx of the thub
Action: adducts thumb
Innervation: ulnar nerve
What is the extensor retinacula and what is it fxn
Fascia in the that extends over the posterior portion of the radius and ulna
fxn= to keep the extensor tendons in position and prevent “bowstringing”
What bones do the is the flexor retinacula (transverse carpal ligament) connect
the scaphoid and trapezium bones on the radial side to the hamate and pisiform on the ulnar side
What is the area inferior to the flexor retinacula and superior to the distal carpals
the carpal tunnel
What important structures lie within the carpal tunnel
the tendons of the flexor pollicis longus, the flexor digitorum superficialis, flexor digitorum profundus, and the median nerve
What nerve does carpal tunnel syndrome affect
the median nerve
Even though the palmer cutaneous nerve is a branch of the median nerve why is NOT affected in carpal tunnel syndrome
because it branches from the median nerve proximal to the carpal tunnel
What important structures lie between the palmar carpal ligament and the flexor retinacula
the ulnar nerve, the palmaris longus nerve, and the ulnar artery (These are NOT in carpal tunnel)
Why is coordination of thumb lost in carpal tunnel
because the median nerve innervates the thenar muscles
How can you detect irritated nerves like in the case of carpal tunnel
Tinels sign= its were you tap on a nerve to illict a pins and needles feeling (paraesthia)
What is skiers thumb
the rupture of the ulnar collateral ligament of the thumb
What important structures lie deep to the anatomical snuff box
the radial artery, the radial nerve, the scaphoid and the trapezium
Pain in the anatomical snuff box after a fall on an outstretched hand may indicate what and why is it important
fx scaphoid
important because scaphoid fx may cause loss of blood supply to that area, and since this area is where the wrist/hand articulates with the radius loss of blood= necorsis= loss of wrist fxn.
What 2 arteries form the superficial palmar arch
the superficial ulnar and radial arteries
What is Allen’s test
test the patency of the radial and ulnar arteries as well as the collateral circulation of the hand
commonly used to reduce risk of ischemia prior to radial ABG
