Hand and wrist anatomy Flashcards
It is also known as transverse carpal ligament
Flexor retinaculum
Thickening of deep fascia that holds the long flexor tendons in position at the wrist
Flexor retinaculum
Where is the flexor retinaculum stretched across?
front of the wrist
Converts the concave anterior surface of the wrist into an osseofascial tunnel, the carpal tunnel
Flexor retinaculum
Where is the flexor retinaculum medially attached?
Pisiform bone and the hook of the hamate
Where is the flexor retinaculum laterally attached?
Tubercle of the scaphoid and the trapezium bones
Describe the attachment of flexor retinaculum to the trapezium
Consists of superficial and deep parts and forms a synovial-line tunnel for passage of the tendon of the flexor carpi radialis
Corresponds to the distal transverse skin crease in the front of the wrist and is continuous with the deep fascia of the forearm
Proximal border of flexor retinaculum
The distal border of flexor retinaculum is…
Attached to the palmar aponeurosis
Passage of the median nerve and the flexor tendons of the thumb and fingers
Carpal tunnel
Deeply concave on its anterior surface and forms a bony gutter
Carpal tunnel
Bones of the hand and flexor retinaculum
Carpal tunnel
Has restricted space between the tendons of the flexor digitorum superficialis and the flexor carpi radialis muscles
Carpal tunnel
The long flexor tendons to the fingers and thumb pass through this tunnel, and are accompanied by the median nerve
Carpal tunnel
Only nerve that passes through the carpal tunnel
Median nerve
The median nerve is associated with this health condition
Carpal tunnel syndrome
Flexor retinaculum: structures pass superficially (medial-lateral)
Flexor carpi ulnaris tendon, ulnar nerve, ulnar artery, palmar cutaneous branch of the ulnar nerve, palmaris longus tendon (if present), palmar cutaneous branch of the median nerve
Flexor retinaculum: structures pass deeply (medial-lateral)
Flexor digitorum superficialis tendons, flexor digitorum profundus (share synovial sheath with FDS), median nerve, flexor pollicis longus tendon, flexor carpi radialis tendon
The anatomical snuffbox is also known as…
Radial fossa
Where is the radial fossa located?
Base at the wrist and apex directed at the thumb, or posterolateral side of the wrist and the 1st metacarpal by the extensor tendons passing into the thumb
The tendon of the extensor pollicis longus is the ___ border of the ____.
ulnar (medial), anatomical snuffbox/radial fossa
These are the radial (lateral) borders of the radial fossa.
Tendon of the extensor pollicis brevis, tendon of the abductor pollicis longus
What is the proximal border of the anatomical snuffbox?
Styloid process of the radius
These are the floor boundaries of the anatomical snuffbox.
Carpal bones, scaphoid, trapezium
The skin is the ___ border of the radial fossa.
Roof
Passes obliquely through the anatomical snuffbox and lies adjacent to scaphoid and trapezium.
Radial artery
This associated area on the back of the hand innervates the dorsal surface of the lateral digits.
Branch of radial nerve
Crosses the anatomical snuffbox to the anterolateral aspect of the forearm
Cephalic vein
Arises from dorsal venous network of the hand
Cephalic vein
Most commonly fractured carpal bone
Scaphoid
What is the other term for scaphoid fracture?
Foosh
Why is the scaphoid at risk of avascular necrosis after fracture?
‘Retrograde blood supply’ enters at is distal end
The extensor retinaculum is the thickening of deep fascia that stretches across which area of the wrist?
Across the back of the wrist
It holds the long extensor tendons in position and converts the grooves on the posterior surface of the distal ends of the radius and ulna into 6 separate tunnels for the passage of the long extensor tendons
Extensor retinaculum
Tunnels are each line with ____ sheath that extends proximal and distal to the retinaculum on the tendons
Synovial
They are separated from one another by fibrous septa that extend from the deep surface of the retinaculum to the underlying bones.
Tunnels
Where is the extensor retinaculum medially attached?
Pisiform bone and the hook of the hamate
Where is the extensor retinaculum laterally attached?
Distal end of the radius
The upper border of the extensor retinaculum is continuous with the deep fascia of the ____.
Forearm
The lower border of the extensor retinaculum is continuous with the deep fascia of the ____.
Hand
Extensor retinaculum: structures pass superficially (medial-lateral)
Dorsal cutaneous branch of the ulnar nerve, basilic vein, cephalic vein, superficial branch of the radial nerve
Extensor retinaculum: structures pass deeply (medial-lateral)
Extensor carpi ulnaris tendon, extensor digiti minimi tendon, extensor digitorum and extensor indicis tendons, extensor pollicis longus tendon, extensor carpi radialis longus and brevis tendons, abductor pollicis longus and extensor pollicis brevis tendons
Forms the thenar eminence in the lateral surface of the palm
Thenar muscles
Thenar muscles are responsible for the…
Opposition of the thumb
Innervation of thenar muscles
Recurrent branch of the median nerve (except the adductor pollicis)
Quadrangular muscle that lies deep to the APB and lateral to the FPB
Opponens Pollicis
What does the Opponens Pollicis do?
Opposes the thumb, flexes and rotates 1st metacarpal medially at the carpometacarpal joint opposition
Muscle that assists the opponens pollicis during early stages of opposition by rotting proximal phalanx slightly medially
Abductor Pollicis Brevis
Short abductor of the thumb that forms the anterolateral part of the thenar eminence
Abductor Pollicis Brevis
What does the Flexor Pollicis Brevis do?
Flexes the thumb at the carpometacarpal and metacapophalangeal joints
Short flexor of the thumb that aids in its opposition, located medially to the APB
Flexor Pollicis Brevis
Large, triangular muscle with two heads (artery passes anteriorly through the space between these 2 heads)
Adductor pollicis
Adductor pollicis head with origin of 2nd and 3rd metacarpal bones
Oblique head
Adductor pollicis head with origin of 3rd metacarpal bone
Transverse head
Adducts the thumb, moving it to the palm of the hand, gives power to grip
Adductor Pollicis
Produces the hypothenar eminence on the medial side of the palm and moves the little finger
Hypothenar muscles
Found in the hypothenar compartment along with the 5th metacarpal
Hypothenar muscles
Innervation of hypothenar muscles
Deep branch of the ulnar nerve
Thenar muscles
Opponens pollicis, abductor pollicis brevis, flexor pollicis brevis, adductor pollicies
Hypothenar muscles
Abductor digiti minimi, flexor digiti minimi brevis, opponens digiti minimi
Most superficial muscle that abducts the 5th finger and helps flex its proximal phalanx
Abductor digiti minimi
Lies lateral to the abductor digiti minimi, flexes the proximal phalanx of the 5th finger at the metacarpophalangeal joint
Flexor digiti minimi brevis
Quandrangular muscle that lies deep to the abductor and flexor of the 5th finger
Opponens digiti minimi
Draws the 5th metacarpal anteriorly and rotates it laterally, acts exclusively at the carpometacarpal joint
Opponens digiti minimi
Intrinsic hand muscles
Lumbricals, interossei, palmaris brevis
How many lumbricals are there?
4
Lumbricals origin
tendons of flexor digitorum profundus
Flexes the fingers at the metacarpophalangeal joints and extend at the interphalangeal joints
Lumbricals
Lumbricals insertion
extensor expansion of medial 4 fingers
Lumbricals nerve supply and nerve roots
1st and 2nd: median nerve, 3rd and 4th: deep branch of ulnar nerve, Nerve roots: C8-T11
Located between the metacarpals that produce the flexion at the metacarpophalangeal joints and extension of the interphalangeal joints
Interossei
How many interossei are there?
8
2 groups of interossei
Palmar interossei (PAD), dorsal interossei (DAB)
Small, thin muscle found superficially in the subcutaneous tissue of hypothenar eminence that corrugates skin to improve grip of palm
Palmaris brevis
Where does palmaris brevis originate?
flexor retinaculum, palmar aponeurosis
The palmaris brevis is innervated by…
superficial branch of the ulnar nerve
A direct continuation of the ulnar artery entering the palm, curves laterally behind the palmar aponeurosis and in the front of the long flexor tendons
Superficial palmar arch
Superficial palmar arch is completed on the ____ side by one of the branches of the _____ artery.
Lateral, radial
Where is the curve of the superficial palmar arch located?
Across the palm, level with the distal border of the fully extended thumb
Arose from the convexity of the arch and pass to the fingers
4 digital arteries
Each common palmar digital artery divides into…
a pair of proper digital arteries which run along the adjacent sides of 2nd-4th digits
Three common palmar digital arteries anastomose with…
palmar metacarpal arteries from the deep palmar arch
Arises in front of the flexor retinaculum, passes between the abductor digiti minimi and the flexor digiti minimi, and joins the radial artery to complete the deep palmar arch
Deep branch of the ulnar artery
Direct continuation of the radial artery, enters through the anatomical snuffbox
Deep palmar arch
Superior branch sent by deep palmar arch
takes part in the anastomosis around in the wrist joint
Inferior branch sent by deep palmar arch
joins the digital branches of the superficial palmar arch
It curves medially beneath the long flexor tendons and in front of the metacarpal bones and interosseous muscles
Deep palmar arch
Where does the curve of deep palmar arch lie?
at a level with the proximal border of the extended thumb
The deep palmar arch gives rise to…
3 palmar metacarpal arteries and princeps pollicis artery
Where is the deep palmar arch completed
on the medial side by the deep branch of the ulnar artery
How many phalanges do you have in each hand?
14
What belongs to the proximal row of carpal bones?
Triquetral
Scared : Scaphoid
Lovers : Lunate
Try : Triquetrum
Positions : Pisiform
That : Trapezium
They : Trapezoid
Can’t : Capitate
Handle : Hamate
[not an answer] mnemonics
10 structures which pass through the carpal tunnel
Median nerve, flexor pollicis longus (1 tendon), flexor digitorum superficialis (4 tendons), flexor digitorum profundus (4 tendons)
The pulse you feel in the anatomic snuffbox emanates from the…
radial artery
These muscles are primarily responsible for abduction and adduction of the fingers of the hand
Interossei muscles
