Cranial Strains (4-8 Ferril)

Question 1

what are the three things you need to know about strains

Answer 1

what motion occurs at the SBS
define the axis/axes of motion involved
physiologic or pathologic motion

Question 2

what are the 6 cranial strains

Answer 2

flexion/extension- inherent motion of SBS (can still get SD) 
torsion
sidebending rotation
vertical strains 
lateral strains 
SBS compression

Question 3

what are the two midline bones we care about and what is their motion?

Answer 3

sphenoid and occiput

flexion and extension

Question 4

what are the paired bones?

main motion?

Answer 4

Temporals, parietals, frontals, ethmoid (lateral mass), nasals, lacrimals, maxillae, palatines, zygomae, inferior conchae & mandible

external and internal rotation

Question 5

physiologically, flexion of the cranium occurs with what other motion?

Answer 5

external rotation

“flexternal rotation”

Question 6

physiologically, extension of the cranium occurs with what other motion?

Answer 6

extension

Question 7

what is the reciprocal tension membrane

Answer 7

creates a tensegrity model that guides the motion of cranial bones b/c this membrane acts as a guide wire

falx cerebri
tentorium cerebelli
formed by dural reflections

Dura is contiguous with periosteum of skull, and extends throughout the spinal column creating link to sacrum and throughout the body

Question 8

what is the vault hold

which fingers are on which bones

Answer 8

Hands are in such a position to be able to palpate and observe motion of the SBS though contact with the sphenoid and occiput

Index fingers on the greater wings of the sphenoid
Pinky fingers on the lateral angles of the occiput

Enables the operator to feel the dysfunction in order to initiate treatment
Treatment also begins with this hold

Question 9

all cranial motion at the SBS is named for motion of the….

Answer 9

motion of the basi-sphenoid on the basi-occiput

Question 10

what are the physiological strains

Answer 10

flexion/extension
torsions
sidebending rotation

These are normal except when the SBS gets stuck there, then you get SD

Question 11

flexion and extension occur about which axis and in which directions do the sphenoid and occiput rotate?

Answer 11

occur about parallel transverse axis about the level of foramen magnum and body of sphenoid

sphenoid and occiput rotate around in opposite directions

Question 12

what is the motion of the sphenoid and occiput during flexion?

Answer 12

basiocciput and basisphenoid move cephalad while occipital squama and wings of sphenoid move caudally (inferior)

landmarks move inferiorly on the patient and away from your fingers

Question 13

what is the motion of sphenoid and occiput during extension and what do you feel in your fingers

Answer 13

your fingers will move superiorly and towards you on the patient and the base moves away from you.

basiocciput and basisphenoid move caudad (inferior) and the occipital squama and wings of sphenoid move cephalad

Question 14

explain what the diagnosis of flexion feels like under your fingers

Answer 14

In the vault hold
Index fingers (on the greater wings of the sphenoid)
Move inferiorly and spread apart slightly
Pinky’s (on the occipital lateral angle)
Move inferiorly and spread apart slightly

Question 15

explain what the diagnosis of extension feels like on your fingers

Answer 15

In the vault hold
Index fingers
Move superiorly and approximate slightly
Pinky’s
Move superiorly and approximate slightly

Question 16

during torsion which directions do the sphenoid and occiput rotate and around what axis

Answer 16

opposite directions

around an A-P axis.

Question 17

what is torsion SD named for

Answer 17

Named by the superior greater wing of the sphenoid
Which is mirroring the motion of the basi-sphenoid

In the vault hold
One greater wing superior to the other
AND
The opposite occipital angle more superior than the other

Question 18

name the diagnosis:

Right greater wing superior and left occipital angle superior =

Answer 18

right SBS torsion

Right index finger moves superiorly in comparison to the left
Left pinky moves superiorly in comparison to the right

Question 19

what do you feel if there is a left SBS torsion

Answer 19

Left index finger moves superiorly in comparison to the right
Right pinky moves superiorly in comparison to the left

Question 20

what occurs with sidebending rotation

what is the axis of rotation

what does it feel like on the side of SD

what is it named for

Answer 20

Sphenoid and occiput rotate around two sets of axes
–To sidebend –> OPPOSITE directions around
parallel vertical axes

-To rotate–>
in the same direction
A-P axis

Altogether this gives the sense of convexity (fullness) and inferior motion on one side

Named for the side of the convexity and inferior motion

Question 21

what occurs during right SBS sidebending and rotation

Answer 21

Right index and pinky fingers move inferiorly and spread slightly in comparison to the left

Question 22

what occurs with left SBS and rotation

Answer 22

Left index and pinky fingers move inferiorly and spread slightly in comparison to the right

Question 23

what are the NON physiological strains

Answer 23

never Normal at the SBS

usually happen in response to trauma

lateral strains (aka lateral shears)
vertical strains (aka vertical shears)
SBS Compression

Question 24

what occurs in a lateral stain

Answer 24

sphenoid and occiput rotate in the same direction about parallel vertical axes

resulting in a lateral shearing force at the SBS

lateral strains are named for the direction the basosphenoid moves (so even though the wings of the sphenoid are moving to the left, the base of the sphenoid moved right)

Question 25

what do you feel in the vault hold with a lateral strain

Answer 25

In the vault hold, your hands will form a parallelogram.

Index fingers will shift one direction, while the pinky fingers shift in the opposite

Right lateral strain:
Both index fingers shift right
Both pinky fingers shift left

Question 26

what is a result in babies of a lateral strain

Answer 26

plagiocephaly - weird looking head

Question 27

for a left lateral shear what happens with you fingers

Answer 27

both index fingers shift right

both pinky fingers shift left

Question 28

for a right lateral shear what happens to your fingers

Answer 28

Both index fingers shift left

Both pinky fingers shift right

Question 29

in a vertical strain, what direction do the sphenoid and occiput rotate and about what axis

what are vertical strains named for

Answer 29

Sphenoid and occiput rotate
in the same direction about
parallel transverse axes (as in flexion/extension)

which results in a shearing force at the SBS.

One bone is in flexion while the other is in extension.

Vertical strains are named by the direction of the basisphenoid
Superior or inferior

Question 30

in the vault hold what will you feel for a vertical strain

Answer 30

In the vault hold the index fingers will move the OPPOSITE direction of the basisphenoid

Superior vertical strain is “wings down, base up”

Inferior vertical strain is “wings up, base down”

Question 31

what occurs in a superior vertical strain on your fingers

Answer 31

Both index fingers shift inferiorly (as the base moves superiorly)
Both pinky fingers shift superiorly

Question 32

what happens in an inferior strain to your fingers

Answer 32

Both index fingers shift superiorly (as the base moves inferiorly)
Both pinky fingers shift inferiorly

Question 33

you put your fingers in the vault hold and you don’t feel any motion at the landmarks….. what is it.

Answer 33

SBS compression

Bowling ball head

fingers of both hands approximate

More commonly, because this severely limits the resiliency of the SBS, flexion and extension are limited

Often these heads will feel hard and generally limited in movement of any kind

Question 34

what is the SBS compression
about what axis ?

what are your shadow hands doing for this SD

Answer 34

Approximation of the sphenoid and occipital bases as they compress together along the A-P axis.

shadow hands:
Index and pinky fingers on both sides will approximate indicating sphenoid compression onto the occiput
OR
No motion is felt at the SBS

Question 35

what are some causes of cranial SD

Answer 35

Birth trauma
Intrauterine position
Head trauma 
Falls on the buttock**
Surgical trauma
Somatic dysfunction from other areas of the body
Viscero-somatic Reflexes
other

Question 36

what are some potential traumatic forces involved in superior vertical strains

Answer 36

• Caudal (inferiorly directed) force applied centrally over the anterior-superior frontal bone.
• Force to the superior occiput (near lambda) & directed from superior/posterior to anterior.

Question 37

what are some causes of an inferior vertical strain

Answer 37

Caudal force transmitted to the basisphenoid such as a caudal force transmitted from bregma.

• A cephelad force transmitted to the condylar parts such as a fall on the base of the spine (ie. landing on the buttocks with a force transmitted up the spine).***
• A caudal force transmitted over the bilateral posterior-superior parietal bones or along the posterior sagittal suture.

Question 38

what are some potential traumatic forces involved in a SBS compression

Answer 38

Force directed along the AP axis leading to longitudinal compression of the SBS. May originate at nasion or at opisthion.

Question 39

what are some potential causes of lateral strains

Answer 39

Lateral to medial directed force applied over the greater wing of the sphenoid pushing the greater wings to the left or right.

-Lateral to medially directed force applied over the occiput pushing the posterior aspect of the occiput left or right.

Question 40

what are some potential traumatic forces involved in external rotations of the temporal bones

Answer 40

Force applied to the left mandible in a left to right direction yields a right externally rotated temporal bone rotation and a left internally rotated temporal bone rotation.
-Traction of one side of the mandible due to dental work yields internal rotation on the ipsilateral side as the traction and external rotation on the contralateral side of the traction forces.