Hand Anatomy Flashcards
what plane does thumb flexion/extension occur in?
frontal
what plane does thumb adduction/abuction occur in?
sagittal
how many carpal bones are there
8
name the four proximal carpal bones from lateral to medial
scaphoid
lunate
triquetrum
pisiform
name the four distal carpal bones from lateral to medial
trapezium
trapezoid
capitate
hamate
what carpal is most commonly fractured?
scaphoid
what carpal is most commonly dislocated?
lunate
what carpal is most commonly arthritic?
trapezium
what is the mnemonic for carpal bones?
Some Lovers Try Positions That They Cannot Handle
which metacarpal is most commonly fractured? what is the name for this fracture?
5th…boxers fracture
the antebrachial fascia continues as what in the medial palmar surface of the hand?
palmar aponeurosis
the palmar aponeurosis has what to divide the hand?
septum of the palmar aponeurosis divide the hand into compartments
name the five compartments of the hand
hypothenar thenar central adductor interosseus
what do the septum dividing the compartments of the hand limit in the hand?
spread of infection
the base of the palmar aponeurosis turns into what at the digits?
fibrous digital sheaths for each finger
what three things do fibrous digital sheaths enclose?
FDS and FDP tendons and synovial sheaths
what are the ligaments that compose the fibrous digital sheaths?
annular and cruciform ligaments
annular ligaments form what shape around the FDP/FDS tendon and snynovial sheaths?
a circular ring structure
cruciform ligaments form what shape around the FDP/FDS tendon and snynovial sheaths?
a cross structure
explain how we develop a trigger finger
trauma/inflammation along the tendons of the FDS/FDP lead to a nodule that can get stuck as it goes through the annular ligaments of the fibrous digital sheath
what is another name for trigger finger?
stenosing tenosynovitis
what two fingers commonly get stenosing tenosynovitis?
ring finger and thumb
what are the synovial tendon sheaths?
tubular envelopes surrounding the FDS and FDP tendons of the digits…it is within the fibrous digital sheath
what is inflammation of synovial tendon sheaths called?
tenosynovitis
where is the hypothenar compartment located in the hand?
medial portion
what do the muscles of the hypothenar compartment control?
movement of the 5th finger
name the three muscles of the hypothenar compartment
abductor digiti minimi
flexor digiti minimi brevis
opponen digiti minimi
what nerve innervates the muscles of the hypothenar compartment?
deep branch of the ulnar nerve
what roots innervate the muscles of the hypothenar compartment?
c8 and t1
where is the thenar compartment of the hand?
thumb
what is the main action that the thenar compartment is responsible for?
opposition of the thumb
name the three muscles of the thenar compartment of the hand
abductor pollicis brevis
flexor pollicic brevis
opponens pollicis
what is the only muscle that can oppose the thumb?
opponens pollicis
what nerve innervates the muscles of the thenar compartment?
recurrent branch of the median nerve
what roots innervate the muscles of the thenar compartment?
C8 and T1
what nerve innervates the abductor pollicis brevis?
recurrent branch of median nerve
what nerve innervates the flexor pollicis brevis?
recurrent branch of median nerve
what nerve innervates the opponens pollicis?
recurrent branch of the median nervre
where is the adductor compartment of the hand located?
just medial to the thenar compartment but deep
what is the role of the muscles of the adductor compartment of the hand?
adduction of the thumb
name the muscle in the adductor compartment of the hand
adductor pollicis
what nerve innervates the adductor pollicis?
deep branch of the ulnar nerve (C8T1)
where is the central compartment of the hand located?
just beneath the palmar aponeurosis
name the three structures that are in the central compartment of the hand
long flexor tendons of the FDS and FDP
neurovasculature structures of the hand
lumbrical muscles
what do the lumbrical muscles originate from?
the FDP tendons in the hands
where do the lumbrical muscles insert?
lateral sides of the extensor expansion (hood) on digits 2-5
what are the two actions of the lumbrical muscles?
flex the metacarpophalnageal joint and extend the interphalangeal joints
what two muscles of the hand help form the extensor expansion?
lumbrical and interossei
the lateral two lumbricals are innervated by what nerve? roots?
median C8T1
the medial two lumbricals are innervated by what nerve? roots?
ulnar nerve C8T1
where is the interosseus compartment located in the hand/
between the metacarpal bones
what muscle group is in the interosseus compartment of the hand?
interossei muscles
name the two groups of interossei muscles
palmar and dorsal
palmar interossei muscles help with what movement?
adduction digits 2-5 to axial line of middle digit
dorsal interossei muscles help with what movement?
abduction digits 2-5 away from axial line of middle digit
where do interossei muscles origin and insert?
origin on shafts of metacarpals and insert into the extensor expansion
what nerve innervates all the interossei muscles? what roots?
deep branch of the ulnar nerve C8 and T1
name the three flexor muscles of the hand that are extrinsic and must traverse under the flexor retinaculum
flexor digitorum superficialis
flexor digitorum profunda
flexor pollicis longus
carpal tunnel has passage for what structures?
9 tendons from the muscle that pass under the flexor retinaculum and the median nerve
the median nerve provides sensation to what portion of the hand?
lateral portion of the palmar aspect
what is branch of the median nerve that arises just proximal to the carpal tunnel?
palmar carpal branch
what does the palmar carpal branch provide sensation to?
central palm area
what is the branch of the median nerve that arises just after it comes out of the carpal tunnel?
recurrent branch
what is the branch of the median nerve other than the recurrent branch that arises after it comes out of the carpal tunnel?
common digital nerve
what does the common digital nerve of the median nerve become?
proper digital nerves
what digits does the median nerve proper digital branches provide sensation to?
first 3.5 digits
so if a patient has impingment of the median nerve in carpal tunnel…what two symptoms can we see in the hand?
paraesthesia, anasthesia, hypoesthesia of lateral 3.5 digits
AND
motor loss of thenar muscles…inability to oppose thumb
what digits does the ulnar nerve provide sensation to?
the medial 1.5
what is the branch of the ulnar nerve that goes to the medial 1.5 digits?
common then proper digital branches
does the ulnar artery enter anterior or posterior to the flexor retinaculum?
anterior
name the two branches of the ulnar artery in the hand
superficial palmar arch
deep palmar branch
name the two branches of the radial artery that feed the index finger and the thumb
radial indicis and princeps pollicis arteries
the radial artery feeds what two fingers in the hands?
index and thumb
aside from the radial indicis and the princeps pollicips arteries, what is the other branch of the radial artery in the hand?
deep palmar branch
the deep palmar branch of the radial artery anastamoses with what artery?
deep palmar branch of the ulnar artery
the superficial palmar arch of the ulnar artery anastamoses with what?
a small superficial branch of the radial artery
so what happens if you cut circulation to the ulnar artery in the hand?
anastomoses have ya covered with the radial deep palmar branch and the superficial branch that meets the superficial palmar arch