Introduction to Sacrum Flashcards Preview

OS II Exam #1 > Introduction to Sacrum > Flashcards

Flashcards in Introduction to Sacrum Deck (33):
1

lumbarization of the sacrum

when S1 and S2 do NOT fuse

2

sacralization of the lumbar spine

when L5 fuses to S1

3

superior aspect

base

4

inferior aspect

apex

5

anterior surface

concave

6

posterior surface

convex

7

medial row/crest

fusion of sacral articular processes

8

lateral rows/crests

fusion of sacral transverse processes

9

inferolateral angle (ILA)

curve at the end of the lateral rows

10

sacral canal

contains the cauda equina and for bilateral sacral foramina for the ventral and dorsal rami of the sacral spinal nerves S1-S4

11

sacral hiatus

defect near the apex, where the lamina failed to close

12

coccyx

made up of 4 vertebrae
lowest part of the spinal column
coccyx attaches to the sacral apex via the sacrococcygeal joint
ganglion impair = where right and left sympathetic chains join rests on anterior aspect of the coccyx

13

palpatory bony landmarks

sacral base
sacral sulci
ILA

14

sacral sulci

to bilateral palpable grooves medial and slightly superior to the PSIS

15

sacrotuberous ligament

attaches sacrum to ischial tuberosity
works w/ sacrospinous ligament stabilize anterior motion, preventing posterior superior rotation

16

sacrospinous ligament

attaches sacrum to ischial spine
works w/ sacrotuberous ligament stabilize anterior motion, preventing posterior superior rotation

17

iliolumbar ligament

attaches 4th and 5th lumbar vertebra to iliac crests
stabilizes posterior motion restricting anterior motion of of L4/L5
upper part blends in with the sacroiliac ligament

18

primary - intrinsic m of the pelvic diaphragm

levator ani group
pubococcygeus m
puborectalis m
iliococcygeus m
cocygeus mm

19

secondary - mm considered to have partial attachment to the true pelvis

rectus abdominis
transverse abdominis
internal and external oblique
quadratus lumborum
also m of the posterior anterior and medial compartments of the lower extremity

20

dura mater

layers of fibrous CT
tension in this CT has a direct effect on the cranial and sacral bone motion which it attaches to
dural connections b/w cranium and sacrum (C1 and C2 to S2)

21

force closure

holding an object by pressure on the sides
created by mm, lig, and fascia surrounding the SI joint

22

form closure

stacking or the use of a roman arch as a self supporting structure
the sacrum acts as the keystone of the arch being wedged b/w iliums

23

superior

respiratory - axis for respiratory motions as well as nutation and counternutation from SBS flexion/extension

24

middle

postural or sacroiliac axis for flexion/extension in sitting and standing

25

inferior

iliosacral axis for rotation of the iliums on the sacrum
at the level of the inferior pole of the lower sacral articulation

26

oblique axes of motion

where dynamic/torsional motion occur
named for the cephalad side

27

respiratory motion

around superior transverse axis
with inhalation sacral base moves posteriorly while sacral apex moves anteriorly
decreased lumbar lordosis
w/ exhalation sacral base moves anteriorly while sacral apex moves posteriorly (increased lumbar lordosis)

28

postural motion

in standing and seated positions
around middle transverse axis
flexion and extension corresponding to anatomical nomenclature same terminology as used with the spine

29

postural motion - flexion

forward bending
sacral base moves anterior sacral apex moves posterior

30

postural motion - extension

backward bending
sacral base moves posterior, apex moves anterior

31

craniosacral flexion (couternutation)

influenced by the dura the sacral base moves posteriorly and the apex moves anteriorly

32

craniosacral extension (nutation)

sacral base moves anteriorly and the apex moves posteriorly

33

dynamic motion

occurs when walking
occurs around oblique axes
sacral base moves forward on one side then the other side around the oblique axes
as this occurs the innominates are constantly rotation in opposite directions to one another (one rotates anteriorly, the other posteriorly)