Intro to Sacrum Flashcards Preview

COM Anatomy, Biochemistry, OS > Intro to Sacrum > Flashcards

Flashcards in Intro to Sacrum Deck (45):
1

Bony anatomy of sacrum: sacral canal

contains cauda equina

2

Bony anatomy of sacrum: sacral hiatus

defect near the apex where the lamina failed to close

site of sacral epidural nerve blocks injected

3

Bony anatomy of sacrum: Coccyx

4 vertebrae, some fused some not
attached to sacral apex via sacrococcygeal joint
possesses the ganglion impar

4

Bony anatomy of sacrum: ganglion impar

where right and left sympathetic chains meet on the surface of the coccyx

5

male vs female sacrum characteristics: angle between ischial tuberosities

more than 90 deg in women, 90 or less in men typically

6

male vs female sacrum characteristics: sacrum

tilted forward in men, tilted backwards in women

7

male vs female sacrum characteristics: pelvic outlet

big pelvic outlet in women, small pelvic outlet in men

8

sacral sulci: location

two bilateral palpable grooves medial and slightly superior to the PSIS

9

True pelvic ligaments

anterior sacroiliac lig
posterior sacroiliac lig
interosseous sacroiliac lig

10

Accessory pelvic ligaments

sacrotuberous lig
sacrospinous lig
ililumbar lig

11

accessory lig =

ligs that attach to other ligs, tendons, or fascia

12

True Pelvic Ligaments: Anterior/ventral sacroiliac ligament

flat bands
attach from 3rd sacral segment to preauricular surace of ilium

13

True Pelvic Ligaments: interosseous sacroiliac ligament

massive bands attaching medial sacral crests to the iliac tuberosities

14

True Pelvic Ligaments: Posterior/Dorsal sacroiliac ligament

thicker with multiple layers
connects PSIS to 3rd and 4th sacral segments
close anatomical relations with the erector spinae muscles

15

Sacrotuberous ligament

attaches sacrum to ischial tuberosity

glut max and tendon of biceps femoris attach

has "Friend" lig: sacrospinous lig

both stabilize anterior motion, prevents posterior/superior rotation

16

sacrospinous lig

friend lig: sacrotuberous lig
stabilizes anterior otion

divides space and below into a greater and lesser sciatic foramen

17

iliolumbar ligament

attaches 4th/5th lumbar vertebra to iliac crests

stabilizes posterior motion, restricting anterior motion of L4/L5

upper part blends in with sacroiliac lig

18

Primary muscles of the pelvic diaphragm

levator ani group and coccygeus muscle

19

levator ani group

primary muscle of the pelvic diaphragm. includes pubococcygeus m., puborectalis m., iliococcygeus m.

20

coccygeus mm.

primary pelvic diaphragm m.

21

secondary muscles "considered to have partial attachments to the true pelvis"

rectus abdominis
transverse abdominis

internal and external oblique

quadratus lumborum

22

Dural connections between cranium and sacrum

cranial dural attachment: foramen magnum, C1 and C2
sacral dural attachment: S2

23

Force closure

holding an object by pressure on the sides
created by muscles, ligaments, and fascia surrounding the SI joint

24

Form closure

"stacking" or the use of a roman artch as a self supporting structure

sacrum acts as the keystone of the arch, being wedged between the iliums

25

Sacral forces

angle of the SI joint, wedge the sacrum in an anterior direction

significant pelvic forces pushing posteriorly

significant dorsal SI ligaments help counteract the major pelvic forces pushing posteriorly

26

Sacral axes

2 oblique
3 transverse axises
1 anterior-posterior axis
1 vertical axis

27

respiratory axis

transverse axis 1: Superior (SI axis)

respiratory axis as well as nutation/counternutation

at level of articular process of S2, attachment of the dura

28

Postural/Sacroiliac axis

transverse axis 2: middle (S2 axis)

axis for flexion/extension in sitting and standing

at the level of the body of S2

29

Iliosacral axis

transverse axis 3: inferior S3 axis

at the level of the inferior pole of the lower sacral articulation

axis for rotation of the iliums on the sacrum

at the level of the inferior pole of the lower sacral articulation

30

Right oblique axis

diagonal axis

named for cephalad side

runs from superiorly right to inferiorly left

31

LEft oblique axis

named for cepehalad side

runs superiorly on the left to inferiorly on the right

32

"dynamic motion"

occurs on oblique axis

33

inherent motion

superior transverse axis

34

inhalation and sacral movement around superior axis

sacral base moves posteriorly with inhalation
decreases lordosis

35

exhalation and sacral movement around superior axis

sacral base moves anteriorly with exhalation
increases lordosis

36

postural motion in standing/seated positions around the middle transverse axis

flexion vs extension

flexion = base moves anteriorly, apex posteriorly
extension = base moves posteriorly, apex anteriorly

37

inherent motion

occurs around superior axis
SBS

movement from the sphenobasilar joint/synchondrosis/symphysis joint between cranial bones is transferred to the sacrum via the dural connections


during craniosacral extension, the sacral base moves anteriorly and the apex moves posteriorly

during craniosacral flexion, the sacral base moves posteriorly and the apex moves anteriorly during craniosacral flexion

38

craniosacral extension

during craniosacral extension, the sacral base moves anteriorly and the apex moves posteriorly

39

craniosacral extension

during craniosacral extension, the sacral base moves anteriorly and the apex moves posteriorly

40

what is the relation between craniosacral flexion/extension and postural flexion/extension?

there isn't one. entirely different

41

nutation

sacral base moves anterior, sacral apex moves posteior
occurs with craniosacralSBS extension

42

counternutation

sacral base moves posteriorly. sacral apex movex anteriorly

occurs with craniosacral/SBS flexion

43

Anterior palpatory landmarks

iliac crests
greater trochanter
ASIS
public symphysis

44

posterior palpatory landmarks

PSIS, Sacral base, sacral sulci, inferiolateral angles
ischial tuberositiy

45

cranioflexion vs anatomical flexion

during craniosacral flexion, the sacral base moves posteriorly and the apex moves anteriorly during

during postural (sacral, or anatomical) flexion, the base moves anteriorly and the apex moves posteriorly