lecture 15: intrinsic hand Flashcards
know the surface anatomy of the hand
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the thumb is digit number BLANK
1
the pinky is digit number BLANK
5
the index is digit number BLANK
2
what are the two mounds of muscle on the palm
thenar and hypothenar eminence
what is most lateral, the thenar or hypothenar eminence
the thenar eminence
what joint makes up the knuckle
MCP
what structure lies most superficial on the palm of the hand
palmar aponeurosis
what is the palmar apeunorosis
triangle of deep fascia, in superficial layer of the palm
explain the attachment of the palmar apomeurosis
deep to the skin (dermis) and anchored to it, but superficial to flexor tendons, palmar neurovascular structures)
true or false, the palmar aponeurosis is anchored to the dermis
true
true or false: the palmar aponeurosis is deep to the skin (dermis) and anchored to it, but deep to flexor tendons, palmar neurovascular structures)
false, superficial to the flexor tendons
true or false: palmaris longus tendon always present
no
what is the palmaris brevis
is stretches between palmar aponeurosis to the skin of hypothenar eminence
draws skin over hypothenar emonience to the center of the palm
palmar aponeurosis is the end of what tendon
palmaris longus
what is the flexor retinaculum
ligamentous band stretching from pisiform and hook of the hamate (medial) to the trapezium and scaphoid (lateral)
what forms the roof of the carpal tunnel
flexor retinaculum
what is the function of the flexor retinaculum
creates carpal tunnel and prevents bowing of the flexors of the forearm
=makes a pulley for the flexor tendons
what are the contents of the carpal tunnel
tendons of the FDS (4), FDP (4), FPL (1) and median n
what nerve passes through the carpal tunnel
median n
what muscle tendons pass through the carpal tunnel
FDS
FDP
FPL
what is carpal tunnel syndrome
chronic pressure on the median nerve resulting in numbness and weakness in the hand
true or false: carpal tunnel syndrome is chronic pressure on the ulnar n
false, median
what are some actions that can cause carpal tunnel syndrome
typing, excessive extended wrist position
how many tendons pass through the carpal tunnel
9 total
what nerve passes through the guyons tunnel
ulnar n
true of false: guyon canal can also lead to compression syndromes but in the ulnar n
true
what are the contents that pass through the guyon canal
ulnar a and n
what two things make up the roof of carpal tunnel
flexor retinaculum
guyon canal
what are the 3 muscles that make up the thenar eminence that are innevated by the reccurent branch of the median n
flexor pollicis brevis
abductor polllic brevis
opponens pollicis
what is the origin of the thenar eminence
flexor retinaculum and scaphoid/trapezium
what is the insertion of the thenar eminence (3)
lateral side of PP1 (proximal phalanx 1) for the APB and FPB
the MC1 for the OP
what is the function of the thenar eminence muscles (3)
FPB/APB= flex and abduct thumb and MCP and IP joints and assist in opposition
OP= opposition
opposition motion is a combo of what moves
abduction and flexion
what are the muscles of the thenar eminence inneravted by
the reccurent branch of median n
true or false, the thenar eminence muscles all share a common origin
true
what si the muscle part of the thenar eminence that is an exception to the inneravtion pattern
adductor pollicus
true or false: adductor pollicus has 3 heads and name them
false only 2
transverse head, and oblique head
what is the origin/palmar attachement of the adductor pollicis
oblique head: capitate (and adj), base of the MCII and MCIII
tranverse head: shaft of the MCIII
what is the insertion/thumb attachment of the adductor pollicus
medial side of the base of the first proximal phalanx (PP1)
what is the function of the adductor pollicis
adduction of the thumb
what is the innevation of the addcuctor pollicis
deep ulnar n
the deep ulnar n is a branch of what nerve
ulnar (near guyon cnaal)
how many muscles make up the hypothenar eminence
3
what are the 3 muscles that make up the hypothenar eminence
abductor digiti minini
flexor digiti minimi brevis
opponens digiti minimi
wht is the origin (proximal attachemnt) of the hypothenar eminence
posiform (Abnductor digiti minim)
hook hamate and flexor retinaculum (opponents digiitmi minini and flexor digiti minimi brevis)
what is the insertion of the hypothenar eminence
medial side of the MC5 (opponents digiti minimi)
PP5 (for AB/FL)
what are the functions of the hypothenar eminence
abducts (AB/FL), flexes PIP (AB/FL), and brings 5th digit into opposition to thumn (OP)
what is the innervation of the hypothenar eminence
deep ulnar n (also to adductor pollicus)
true or false: only hypothenar emonence muscles are innervated by the deep ulnar n
false, also the adductor pollicus
what are the origins of the lumbricales
tendons of the FDP (NOT FDL)
what is the insertion of the lumbricales
lateral aspect of the extensor hood
what are the functions of the lumbricals
simultaneus flexion of MCP and extension of the IP joints via extensor hood
what is the inneravtion of the l;umbricales
median n (1 and 2) and deep ulnar (3 and 3)
how many lumbricales do we have
4
lumbricale 1 and 2 go to whar digits
2 and 3
lumbricales 3 and 4 goto what digits
4 and 5
how many palmar interossei are there
3
what is the function fo the palmar interossei
adduction and flexion of the MCP, extension of the IP joints for digits II, IV and V
what is the innervation of the palmar interossei
deep ulnar n
what is the general o/i of the interossei muscles
O: shafts of MCs to the sides of PPs and extensor hoods
how many dorsal interossi are there
4
what is the function of the dorsal interossei
abduction and flexion of MCP, extension of Ip joints for digits II, III, IV
flexor tendons in palm and digits are surrounded by what
synovial sheaths encapsulated by fibrous sheets
explain hoe FDP and FDS run
the FDP runs deep the FDS which splits to allow the FDP to pass through
what is the function of the digital fibrous sheaths
keeps flexors tendons stuck to bone to prevent bowing
understand slide with synovial sheats in the hand
.
ulnar n is where in the hand
guyon canal
median n is deep to what
flexor retinaculum
reccurent branch of medial n supplies what
to thenar eminence except the adductor pollicus
deep ulnar n supples what
hyoothenar eminence, medial 2 lumbricals ( IV and V), adductor pollicus and interossei
lumbricals I and II are directly inneravted by
median n
adductor pollicus is inneravted by what
deep ulnar
nerves on the dorsum are sensory or motor only
sensory
understand sensory innevation of the hand
.
last slides intrisic hand
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