Finger Function

Question 1

describe active insufficiency of wrist

Answer 1

when you make a fist, wrist extends to provide force needed

Question 2

flexor digitorum superficialis is more/less significant than flexor digitorum produnfus

Answer 2

not as important as profundus because it doesn’t go to distal phalanx
-profundus goes to distal phanax

Question 3

synovial fluid

Answer 3

-very low friction
-filtered plasma

Question 4

where is synovial fluid found

Answer 4

joints
-also in CT SHEATH

Question 5

describe healing of tendons with sheath

Answer 5

take longer to heal because don’t have good blood supply

Question 6

pulleys/bands of collagen on fingers

Answer 6

prevent bow stringing of finger tendons

Question 7

KNOW-
extensor digitorum in isolation

Answer 7

in isolation, extensor digitorum can only extend MCP

Question 8

dorsal digital expansion

Answer 8

connective attachments that extensor tendons attach onto phalanges

Question 9

extensor digitorum attaches to what

Answer 9

hood

Question 10

extensor digitorum function

Answer 10

straigthens MCP

Question 11

lumbricals function

Answer 11

straights out IPs

Question 12

what 2 things must occur to straighten out our fingers

Answer 12

-extensor digitorum extends/straigthen MCPs
-lumbricals extends/straighten IPs

Question 13

4 contributors to finger extensor mechanism

Answer 13

-dorsal digital expansion
-extensor digitorum
-dorsal + volar interossei
-lumbricals

Question 14

MCP extension

Answer 14

-extensor digitorum pulls hood proximally
-extensor digitorum cannot extend PIP or DIP; can only extend MCP

Question 15

passive tension of flexor tendons is overcome by ____

Answer 15

lumbrical contraction

Question 16

extension of PIP is always accompanied by ____

Answer 16

DIP extension
-PIP cannot extend without DIP extending

Question 17

what works together to allow writing motion

Answer 17

extensor digitorum + lumbricals

Question 18

see slide 7 of ape hand (Dr. Bishop did not call it this)
-pt can straigthen MCPs but not PIP/DIP

Answer 18

median nerve + lumbricals injury