16.9 Anatomy: Anatomy of the hand Flashcards
What are the 7 layers of the palm?
- Skin, palmaris brevis
- Palmar aponeurosis
- Thenar and hypothenar muscles
- Neurovascular plane
- Long flexor tendons and lumbricals
- Adductor pollicis and neurovasular plane
- Interossei and metacarpals
Where do thenar and hypothenar muscles arise from?
Flexor retinaculum as the palmar aponeurosis
Where does the palmar aponeurosis extend to?
Until thenar/hypothenar eminence (for greater mobility)
What is thickening of palmar aponeurosis called?
Dupuytren’s contracture
What are the actions of abduction/adduction of the thumb in relation to the palm?
At right angles, abduction is Zoidberg claws
What is extension and flexion of the thumb?
Extension: ‘stop’ gesture
Flexion: Thumb folds over palm to touch pinky
What are the thenar and hypothenar muscles?
Thumb and pinky, majority of ‘meat’ on medial and lateral palm
What are the superficial and deep muscles of the thumb and pinky?
Superficially: abductor/flexor
Deep: opponens
What is the relationship between FDS and FDP on the phalynx?
FDS splits into base of middle phalynx, FDP comes through the middle onto the distal phalynx
Which lumbricals are unipennate and which are bipennate?
Unipennate: index, middle
Bipennate: ring, pinky
What nerve is associated with the deep palmar arch?
Deep branch of ulnar nerve
Which finger lacks a palmar interossei?
What do they usually do?
Middle finger
Adduct towards middle finger
Why don’t we need a dorsal interosseus on the pinky or the thumb?
Pinky has ADM
Thumb has APB
What do the interossei allow?
Abduction and adduction
What can dorsi pull on? What does this do?
Extensor extension, wave ‘bye bye’
