Anatomy Forearm and Posterior Hand Flashcards
HOw can you get the MP, PIP, and DIP joint to extend at the same time in a single digit?
THe extensor hood forces them to contract together when the extensor digitorum contracts
What is the MP, PIP, DIP?
MP-> metacarpaphalangal
PIP-> proximal interphalangal
DIP-> distal phalangal
WHen you pull on the extensor hood, you will cause tension/contraction on what two bands?
lateral band and central band
What two muscles work together and extend the interphalangeal joints and flex the metacarpophalangeal joints?
lumbricals and interossei
What does the central band do?
attaches the extensor hood to middle phalanx
What does the lateral bands do?
attach the extensor hood to the distal phalanx
Where do the muscles of the fingers attach?
onto the lateral bad of the extensor hood
if you pull on the long extensor tendon what happens?
You extend you DIP and PIP
What does the FDP (flexor digitorum profundus) do?
flexes the distal interphalangeal joint
What does the FDS (flexor digitorum superficialis) do?
flexes the proximal interphalaneal joint
Without (blank) tendons at wrist you cant make a tight fist.
extensor
What do the tendons of the hand need in order to pass under the retinaculum?
a synovial tendon sheet
What is the retinaculum?
a CT sheeth that holds the tendons of the hands taught to prevent bow stringing and protect proper function
On the posterior side of the hand, what is the retinaculum called?
On anterior side?
the extensor retinaculum
the flexor retinaculum
Are the tendons of the hands exposed to the synovial fluid of the synovial tendon sheeth?
NOOOO, the synovial fluid sheeth forms a double walled synovial fluid filled capsule in which the tendon runs through the center without actually touching the fluid.
Most posterior forearm muscles arise from the common (blank) off the lateral epicondyle or the supracondylar ridge.
extensor tendon
Most posterior forearm muscles arise from the common extensor tendon off the (blank) or (blank).
(remember there are a few exceptions)
lateral epicondyle or the supracondylar ridge
off the sides of humerus
What are the exceptions to the “posterior forearm muscles come from lateral epicondyle or the supracondylar ridge)?
the three thumb muscles, the extensor indices, and the supinator
All posterior muscles are innervated by the (blank)
radial nerve (mostly the dep nerve)
What is the forearm muscle rules of three?
3 muscles to the thumb
3 muscles to the fingers
3 muscles to the wrist
3 muscles that do not cross the wrist joint
What are the three muscles to the thumb?
abductor pollicis longus
extensor pollicis brevis
extensor pollicis longus
What are the three muscles to the posterior wrist?
extensor carpi radialis longus
extensor carpi radialis brevis
extensor carpi ulnaris
What are the three muscles to the fingers?
extensor digitorum
extensor digit minimi
extensor indicis
What are the three muscles that do not cross the wrist joint?
brachioradialis
supinator
anconeus