Hand Muscles (Quiz 2/Exam 2) Flashcards
What are the motions of the hand?
-abduction
-adduction
-extension
-flexion
-opposition
-reposition
The fascia of the palm is continuous with the ______________ fascia and the fascia of the _____________________
antebrachial, dorsum of the hand
The fascia of the palm is thin over the ________ and ____________________, but it is thick centrally where it forms the fibrous palmer aponeurosis and in the finger where it forms the digital sheaths covers the soft tissues and overlies the long flexor tendons
thenar, hypothenar eminences
The fascia of the palm forms the palmer aponeurosis. The proximal end/apex of the triangular palmer aponeurosis is continuous with the ______________ and the _________________
flexor retinaculum, palmaris longus tendon
The palmar aponeurosis forms _____ longitudinal digital bands/rays that radiate from the apex and attach distally to the bases of the proximal phalanges and become continuous with the fibrous digital sheaths which are ligamentous tubes that enclose the synovial sheaths, the superficial and deep flexor tendons, and the _______________________ in their passage along the palmar aspect of their respective fingers
4, tendon of the flexor pollicis longus
The fascia of the palm has flexor digital sheaths that are composed of 5 ______ and 4 _______ parts/pulleys
anular, cruciform (cross-shaped)
A _________________ extends deeply from the medial border of the palmar aponeurosis to the 5th metacarpal
test q
medial fibrous septum
Medial to the medial fibrous septum (of the fascia of the palm) is the medial or ____________ compartment containing the ____________ muscles
hypothenar, hypothenar
The ______________ extends deeply from the lateral border of the palmar aponeurosis to the 3rd metacarpal
test q
lateral fibrous septum
Lateral to the lateral fibrous septum (of the fascia of the palm) is the lateral or __________ compartment containing the __________ muscles
thenar, thenar
Between the hypothenar and the thenar compartments (fascia of the palm) is the the central compartment containing the flexor tendons and their sheaths, the __________, the ___________________, and the digital vessels and nerves
lumbricals, superficial palmar arterial arch
The deepest muscular plane of the palm is the ___________ compartment containing the _____________
adductor, adductor pollicis
Between the flexor tendons and the fascia covering the deep palmar muscles are 2 potential spaces: the _________ space and the __________ space
thenar, midpalmar
Between the flexor tendons and the fascia covering the deep palmar muscles are 2 potential spaces: the thenar space and the midpalmar space. The spaces are bounded by the ____________ passing from the edges of the palmar aponeurosis to the metacarpals
fibrous septa
Between the flexor tendons and the fascia covering the deep palmar muscles are 2 potential spaces: the thenar space and the midpalmar space. Between the spaces is the strong ________________, which is attached to the 3rd metacarpal
lateral fibrous septum
Although most fascial compartments end at the joints, the midpalmar space is continuous with the….
anterior compartment of the forearm via the carpal tunnel
What are the 4 thenar muscles?
1) opponens pollicis
2) abductor pollicis brevis
3) flexor pollicis brevis
4) adductor pollicis
3/4 of the thenar muscles have the same origin/proximal attachment. The attachment is at the flexor retinaculum and tubercles of the scaphoid and trapezium. Which muscles proximally attach here?
1) opponens pollicis
2) abductor pollicis brevis
3) flexor pollicis brevis
What is the origin/proximal attachment for the opponens pollicis?
test q
flexor retinaculum and tubercles of the scaphoid and trapezium
What is the insertion/distal attachment of the opponens pollicis?
test q
lateral side of the 1st metacarpal
What innervates the opponens pollicis?
test q
median n.
What are the actions of the opponens pollicis?
test q
-OPPOSITION
-opposes thumb, draws 1st metacarpal medially to the center of the palm and rotates it medially
What is the origin/proximal attachment of the abductor pollicis brevis?
flexor retinaculum and tubercles of the scaphoid and trapezium
What is the insertion/distal attachment of the abductor pollicis brevis?
lateral side of the base of the the proximal phalanx of the thumb
note: this is the same insertion/distal attachment for the flexor pollicis brevis
What innervates the abductor pollicis brevis?
median n.
What are the actions of the abductor pollicis brevis?
-abducts thumb
-helps oppose thumb
What are the 2 heads of the flexor pollicis brevis?
-superficial head (more medial)
-deep head (more lateral)
What is the origin/proximal attachment of the flexor pollicis brevis?
flexor retinaculum and tubercles of the scaphoid and trapezium
What is the insertion/distal attachment for the flexor pollicis brevis?
lateral side of the base of the proximal phalanx of the thumb
note: this is the same insertion/distal attachment for the abductor pollicis brevis
What innervates the SUPERFICIAL head of the flexor pollicis brevis?
test q
median n.
What innervates the DEEP head of the flexor pollicis brevis?
test q
deep ulnar n.
What is the action of the flexor pollicis brevis?
flex thumb
What are the 2 heads of the adductor pollicis?
-oblique head
-transverse head
What are the origins/proximal attachments for the oblique head of the adductor pollicis?
-bases of 2nd and 3rd metacarpals
-capitate
-adjacent carpals
What is the origin/proximal attachment for the transverse head of the adductor pollicis?
anterior surface of shaft of 3rd metacarpal
What is the insertion/distal attachment for the adductor pollicis?
medial side of the base of the proximal phalanx of the thumb
What are the actions of the adductor pollicis?
adducts thumb towards lateral border of palm
What are the 3 hypothenar muscles?
1) abductor digiti minimi
2) flexor digiti minimi brevis
3) opponens digiti
What is the origin/proximal attachment for the abductor digiti minimi?
pisiform
What is the insertion/distal attachment for the abductor digiti minimi?
medial side of the base of the proximal phalanx of the 5th digit
note: this is the same insertion/distal attachment for the flexor digiti minimi brevis
What innervates the abductor digiti minimi?
deep ulnar n.
What are the actions of the abductor digiti minimi?
-abducts 5th digit
-assists in flexion of its proximal phalanx
What is the origin/proximal attachment for the flexor digiti minimi brevis?
hook of hamate and flexor retinaculum
note: this is the same origin/proximal attachment for the opponens digiti
What is the insertion/distal attachment for the flexor digiti minimi brevis?
medial side of the base of the proximal phalanx of the 5th digit
note: this is the same insertion/distal attachment for the abductor digiti minimi
What is the action of the flexor digiti minimi brevis?
flexes proximal phalanx of the 5th digit
What is the origin/proximal attachment of the opponens digiti?
hook of hamate and flexor retinaculum
note: this is the same origin/proximal attachment for the flexor digiti minimi brevis
What is the insertion/distal attachment for the opponens digiti?
medial border of 5th metacarpal
What are the actions of the opponens digiti?
-draws 5th metacarpal anteriorly and rotates it
-brings 5 digit into opposition with thumb
How many lumbricals are there?
4
What is the origin/proximal attachment for the 1st/2nd lumbricals?
lateral 2 tendons of flexor digitorum profundus (as unipennate muscles)
What is the origin/proximal attachment for the 3rd/4th lumbricals?
medial 3 tendons of flexor digitorum profundus (as bipennate muscles)
What is the insertion/distal attachment of the lumbricals?
lateral sides of extensor expansions of 2nd-5th digits
What are the actions of the lumbricals?
-flex MCP joints
-extend IP joints of 2nd-5th digits
What is the origin/proximal attachment for the dorsal interossei?
adjacent sides of 2 metacarpals (as bipennate muscles)
What is the insertion/distal attachment of the dorsal interossei?
bases of proximal phalanges and the extensor expansions of 2nd-4th digits
What are the actions of the dorsal interossei?
“DAB” - dorsals abducts
-abducts 2nd-4th digits from axial line (middle finger)
-act with lumbricals in flexing MCP joints and extending IP joints
What is the origin/proximal attachment for the palmar interossei?
palmar surfaces of 2nd, 4th, and 5th metacarpals (as unipennate muscles)
What are the insertions/distal attachments for the palmar interossei?
-bases of proximal phalanges
-extensor expansions of 2nd, 4th, and 5th digits
What are the actions of palmar interossei?
“PAD” -palmars adduct
-adduct 2nd, 4th, and 5th digits toward axial line (middle finger)
-assists lumbricals in flexing MCP joints and extending IP joints, and the extensor expansions of 2nd-4th digits
