Starred Lecture Items L9

Question 1

when do somites originate

Answer 1

3rd week of embryogenesis

Question 2

what is a somite

Answer 2

mesodermal segments of embryos originating from stem cells that become the vertebral column, skeletal muscle and dermis.

Question 3

when does the mesoderm differentiate into somites

Answer 3

after day 20

Question 4

how many pairs of somites come from the mesoderm and how many sets of spinal nerves do they eventually create

Answer 4

44 pairs of somites; 31 sets of spinal nerves

Question 5

what happens at the 7th week of embryogenesis regarding upper and lower limbs

Answer 5

upper and lower limbs undergo a 90 degree torsion in opposite directions, elbow goes caudally and knee goes cranially

Question 6

what are:
syndactyly
polydactyly
macrodactyly
adactyly
ectrodactyly
anomalies

Answer 6

syn: fusion of digits
poly: extra digits (usually bilateral)
macro: enlarged digits
a: absence of digits
ectro: lobster claw

Question 7

what are:
amelia
meromelia
phocomelia
anomalies

Answer 7

a: absence of extremities
mero: partial absence of extremities
phoco: shortened lower extremities

Question 8

what are the 4 joints of the UE and are they synovial or functional

Answer 8

glenohumeral (syn)
acromioclavicular AC (syn)
sternoclavicular (syn)
scapulothoracic (functional)

Question 9

what end of the clavicle is flat and what is rounder/pointy

Answer 9

sternal end is flat
acromial end is rounder/pointy

Question 10

what is the antebrachium

Answer 10

forearm

Question 11

what head of the tricep doesnt attach to the humerus

Answer 11

long head

Question 12

is the long head and short head of the bicep biarticulate or triarticulate

Answer 12

triarticulate

Question 13

biarticulate vs triarticulate

Answer 13

bi: works across two joints
tri: works across three joints (ex. shoulder elbow forearm)

Question 14

what vessel runs on top of the superior transverse scapular ligament and what runs under it/through the notch

Answer 14

suprascapular nerve travels through notch/ under ligament
suprascapular artery runs above

Question 15

three types of acromion (which is best)

Answer 15

type I: flat (most healthy/ norm)
type II: curved
type III: hooked (caused by bone spurs/overuse–causes compression of subacromial vessels)

Question 16

most common to least common rotator cuff injury muscle

Answer 16

supraspin=most common
subscap= least common

Question 17

what is a partial vs complete rotator cuff tear called

Answer 17

partial: articular/ bursal side tear
complete: full thickness tear (all the way through the tendon)

Question 18

what is injured in a SLAP injury and where does it start

Answer 18

glenoid labrum (ring of cartilage around shoulder socket/ glenoid) ; starts at 12/1 o clock but can spread

Question 19

total shoulder abduction ROM is…

Answer 19

180 degrees

Question 20

early phase of shoulder humoral rotation (degrees)
what is involved

Answer 20

initial 30 degrees of abduction
GHJ only

Question 21

mid phase of shoulder humoral rotation (degrees)
what is involved

Answer 21

30 degrees to 120 degrees; scapular rotation and GH movement equally 1:1

Question 22

late phase of shoulder humoral rotation (degrees)
what is involved

Answer 22

120 degrees to 180 degrees
mostly GHJ (2/3:1)

Question 23

what three ligaments come off coracoid process

Answer 23

coracoacromial
coracohumeral
coracoclavicular (trapezoid and conoid)

Question 24

separated shoulder and mechanism?

Answer 24

only ac ligament
mechanism: acromioclavicular joint is dislocated but no ligament separation??????

Question 25

piano key injury and mechanism?

Answer 25

dislocation of ac joint plus rupture of two coracoclavicular ligament (trapezoid and conoid ligaments)
mechanism: ????

Question 26

if shoulder capsule is bilaterally instable/loose it is…. if unilateral it is….

Answer 26

born loose if bilaterally
torn loose if unilateral

Question 27

what is a bursa?

Answer 27

synovial membrane goes through fibrous membrane to form bursa
between tendons and fibrous membrane

Question 28

what are the bursas in the shoulder

Answer 28

subscapular bursa
subacromial bursa