Anatomy Posterior Forearm and Hand Flashcards
How can the anterior hand be divided?
into the thenar (thumb) and hypothenar (little finger) compartments and lumbricals and interossei
Are there intrinsic hand muscles in the dorsum of the hand?
no
What are the lumbricals and interossei?
true intrinsic muscles of the hand
What are found lateral and medial to the palmar aponeuroses?
Lateral to the aponeurosis are the thenar mucles
medial to the aponeurosis are the hypothenar muscles
What are the kinds of muscles of the thenar muscles and the hypothenar muscles.
Each has an O A F
opponens, abductor, flexor
What does the palmaris longus tendon turn into?
the palmaris aponeurosis
What is this:
a disease of the palmar fascia resulting in thickening and shortening of fibrous bands on the palmar surface of the hand and fingers
Dupuytren’s contracture
What are the three thenar muscles of the anterior hand?
opponens pollicis
abductor pollicis brevis
flexor pollicis brevis
What nerve innervates the thenar muscles?
the median nerve
Why is the adductor pollicis not considered part of the thenar muscles?
cuz it is not innervated by the median nerve
What are the three muscles of the hypothenar muscles?
opponens digiti minimi
abductor digiti minimi
flexor digiti minimi (brevis)
What nerve innervates the hypothenar muscles?
ulnar nerve
Where do opponen muscles attach to?
to the metacarples
What is known as the million dollar nerve?
the recurrrent branch of the median nerve that goes to thenar muscles; million dollar cuz if you have damage here you will lose your ability to use your thumb (i.e. no grasping)
What canal does the ulnar nerve an artery travel in?
Guyon’s canal
A main entrance to the hand is found in the (blank)
carpal tunnel
What artery and nerve does not pass through the carpal tunnel?
ulnar artery and nerve (cuz they have their own tunnel, the guyon canal ;)
How many tendons and what nerve does the carpal tunnel have?
9 tendons and median nerve
If you compressed the anterior portion of your wrist? What would be the symptoms associated with it?
median nerve
cutaneous issues, numbness, parasthesia in 1, 2, 3, and 1/2 fingers
What are the 9 tendons and the nerve of the carpal tunnel?
4 from the FDS
4 from the FDP
1 from the FPL
median nerve
If your hand is in the anterior position, and you are looking at the carpal tunnel where would you find the FPL?
laterally
What muscles of the hand are associated with long tendons?
lumbricals
What are the muscles on the posterior part of your hand closest to the skin?
the dorsal interosseus muscles
What are the muscles on the anterior part of your hand closest to your skin?
lumbricals
What happens if you rupture the tendon sheath of the 2nd phalanx?
It will rupture into the thenar space
What happens if you rupture the tendon sheaths of the 3rd and 4th phalanges?
it will rupture into the midpalmar space
What happens if tendon sheaths 1 and 5 become infected and rupture?
they rupture into the forearm
The (blank) hold the long flexor tendons tightly against the metacarpals and the phalanges.
fibrous digital sheaths
Bands (blank) and (blank) are on the proximal and middle phalanx respectively, and bands (blank), (blank), and (blank), are near the MP, PIP and DIP respectively.
A2 and A4
A1, A3, and A5
In the finger synovial tendon sheeths, how many tendons are there?
2
Where do the lumbricals originate from?
the flexor digitorum profundus tendons
Where do the lumbricals insert into?
extensor hoods
What are the lumbricals innervated by?
median and ulnar nerves
What side of the tendons of the flexor digitorum profundus do the lumbricals attach to?
the radial side
What fingers are innervated by the median nerve?
1,2,3
What fingers are innervated by the ulnar nerve?
ring and pinky finger
The (blank) nerve takes care of all the intrinisic muscles of the hand, except for the thenar compartment and the lumbricals to the functional midline of the radial side (i.e. index and middle).
ulnar
What does the ulnar nerve innervate?
all the intrinisc muscles of the anterior hand except for the thenar compartment muscles and lumbricals to the funtional midline of the radial side (index and middle)
What are the interosseus muscles?
dorsal and palmar muscles
Where do interosseous muscles originate and where do they insert?
metacarples and insert on the extensor hood
What do the interosseous muscles do?
adduct (palmar muscles adduct PAD
abduct (dorsal muscles abduct) DAB
the MP joints relative to digit 3
Where do we find the dorsal and palmar muscles of the hand?
How is this so?
they are both anterior compartment muscles
Because they are both innervated by the ulnar nerve
How do the interosseous muscles pass the MP joint?
Why is this important?
anteriorly
Cuz they allow for flexion at this joint
The lumbrical and the interosseous muscles insert into the (blank).
extensor hood
So all in all, what do the lumbricals and the interosseous muscles do?
they flex the MP (interosseous) and extend the PIP and DIP (lumbricals)
The FDP flexes the (blank)
distal interphalangeal joint
The FDS flexes the (blank)
proximal interphalangeal joint
If you dont have extensor tendons at your wrist can you make a tight fist?
nope
If you tear off your central band what would happen?
it would extend the DIP and flex the PIP
If you tear off your lateral band what would happen?
cannot extend the DIP
The (blank) artery goes across the snuff box and forms part of the deep palmar arch.
radial artery
What does the deep palmar arch communicate with?
the radial artyer and superficial palmar arch
What do the palmar arches give off?
common digital branches which split and give off small dorsal branches
What is their an important anastomosis between that is utilized in the alan test?
between radial and ulnar arteries
What is the most common wrist fracture in children
fracture of scaphoid
(blank) is permanent failure of healing following a broken bone.
Nonunion
What is worrisome about a scaphoid fracture?
sometimes hard to notice and you get non-union due to poor blood supply and the proximal portion can can undergo necrosis
On the posterior part of your hand, what all does your median nerve innervated?
What about on the anterior part?
just the last part of your thumb, index, middle, and half the ring?
palm and thumb, index, middle and half of ring
On the posterior part of your hand, what all does your ulnar nerve innervate?
On the anterior part of your hand?
the pinky and half your ring finger
pinky and half your ring finger
On the posterior part of your hand, what does the radial nerve innervated?
On the anterior part of the your hand?
most of the back of the hand up to halfway to 1,2,3, and half of a half of 4
just lower part of thumb like the snuff box area
what is the innervation to the shoulder?
to the elbow?
to the wrist?
to the hand?
C5,6
C6,7
C7,8
C8,T1
What innervates the anterior ARM?
musculocutaneous
How is the anterior FOREARM innervated?
all is median except for flexor carpis ulnaris and 4,5 of flexor digitorum profundus
What innervates the anterior hand?
all ulnar except thenar compartment muscles and the three lumbricals to the functional midline on radial side (median)
What nerve innervates the shoulder?
axillary (deltoid and teres minor)
What innervates the posterior ARM and FOREARM?
radial
What is this:
damage to upper trunk of brachial plexus, and shoulder movements are most dramatically affected
Erb-Duchenne paralysis
(C5 and C6) damage
Why will patients with erb-duchenne palsy sometimes have flexes wrists?
because the ulnar nerve is still intacted creating more flexion than usual
What do you call erb-duchenne palsy in adults?
Porter’s tip hand
What is klumpke’s paralysis?
What nerve roots contribute to this damaged part of the plexus?
damage to lower trunk of brachial plexus
C8,T1 contribute and thus will e damaged.
What is most affected in klumpke’s paralysis?
had movements are affected most (remember damage to the lower trunk will affect your medial pectoral, medial brachial, medial antebrachial and ulnar the most, so sad day)
In klumpke’s paralysis, you lose C8 and T1, so what will losing T1 do?
make you lose sympathetics to the head so you will get squinty eyes
If you damage your axillary nerve what will be weakened?
wont be able to abduct
wont have lateral rotation