3-31 Osteopathy in the Cranial Field

Question 1

What is the “dynamic unit of function” concept in regards to the head?

Answer 1

•Dynamic Unit of Function
–Neural System continuity: CNS to ANS
–Connective Tissue continuity: fascia, membranes, bones
–Fluid System continuity: CSF, lymph

Question 2

What is the “inherent immunity” concept in regards to the head?

Answer 2

•Structural Integrity
–which begets functional efficiency
•Healthful nutrition
•Adequate rest, including sleep!
•Inner serenity
•The physician doesn’t heal anything.

Question 3

Cranial bones are ______?

Answer 3

Beveled

Can be observed at squamoparietal sutures

….something something fish.

Question 4

What is “primary respiratory motion”?

Answer 4

•Primary – underlying all other physiologic functions
•
•Respiratory – cellular respiration
•
•Mechanism – cranial articulations

Question 5

What are the 5 tenents of the primary respiratory mechanism?

Answer 5

1. The fluctuation of the CSF and the potency of the tide
2. The mobility of the intracranial and intraspinal membranes, and the function of the reciprocal tension membrane
3. The inherent motility of the central nervous system
4. The articular mobility of the cranial bones
5. The involuntary mobility of the sacrum between the ilia

Question 6

What is tenet 1 of the primary respiratory mechanism? What does it say regarding movement of CSF? Production?

Answer 6

• Movement of the CSF involves circulation and fluctuation
• 70% of CSF is formed at the choroid plexi in the ventricles
• 30% of CSF is formed as CSF extracellular fluid moves into the subarachnoid space.
• The intraventricular and subarachnoid spaces are connected by the foramen of Magendie and the foramen of Luschka
• CSF is drained by the paravascular and extracellular spaces of the CNS

Question 7

Where is CSF produced and channeled?

Answer 7

• CSF produced by the choroid plexi and thought to be channeled through the arachnoid (Pacchionian) granulations
• CSF now thought to be transported through paravascular & extracellular spaces of the CNS

Question 8

What is the cranial rhythmic impulse?

Answer 8

•Fluctuation of the CSF has 2 characteristics:
–Physical potency/energy that acts throughout the body as a hydrodynamic mechanism
–Electrical potential acting in positive and negative phases

•Both are intimately integrated with the reciprocating motility of the CNS

Question 9

What is the speed of the CRI?

Answer 9

•Occur at 10-14* cycles per minute in normal adults

Question 10

For tenet 2, what is the function of the reciprocal tension membrane?

Answer 10

In plain english, they’re apparently talking about the falz cerebri and cerebelli, as well as tentorium cerebelli - apparently called “The Sutherland Fulcrum”.

Function:

partition

support

shock-absorbing

stress-meeting

Question 11

What is dura continuous with?

Answer 11

Dura is contiguous with periostium of calvarium (inside and out) and forms the falxes and tentorium.

Question 12

What are the attachments of the falx cerebri?

Answer 12

•Attachments of the falx cerebri:
–Crista galli of the ethmoid
–Frontal bones along the metopic suture
–Parietal bones along the sagittal suture
–Occiput
–Tentorium cerebelli

Question 13

What are the attachments of the tentorium cerebelli?

Answer 13

•Attachments of the tentorium cerebelli:
–Posterior clinoid processes of the sphenoid
–Petrous ridges
–Mastoid portion of the temporals
–Posteroinferior angles of the parietals
–Transverse ridges of the occiput

Question 14

What are the attachments of the falx cerebelli?

Answer 14

•Attachments of the falx cerebelli:
–Tentorium cerebelli
–Occiput to foramen magnum

Question 15

What happens to the falx cerebri during inhaltion and exhalation?

Answer 15

Inhalation:
–Falx cerebri shifts anteriorly in the arc of its sickle

Exhalation:
–Falx cerebri shifts posteriorly in the arc of its sickle

Question 16

What happens to the crista galli in inhalation and exhalation?

Answer 16

Inhalation:
–Crista galli moves posteriorly

Exhalation:
–Crista galli moves anteriorly

Question 17

What is the motion of the tentorium cerebelli during inhalation and exhalation?

Answer 17

Inhalation:
–Tentorium cerebelli shifts anteriorly and flattens, but is not relaxed

Exhalation:
–Tentorium cerebelli shifts posteriorly and rises

Question 18

What is the motion of the venous sinuses during inhalation and exhalation?

Answer 18

Inhalation:
–Venous sinuses change in shape from “V” to ovoid with increased capacity for drainage of blood. They do not contain muscle within the walls to enhance the return of blood into circulation

Exhalation:
–Venous sinuses change in shape from ovoid to “V” with decreased capacity for drainage of blood.

Question 19

What is the motion of the midline bones during inhalation and exhalation?

Answer 19

Inhalation:
–Midline bones move into flexion

Exhalation:
–Midline bones move into extension

Question 20

What is the motion of the paired bones during inhalation and exhalation?

Answer 20

Inhalation:
–Paired bones move into external rotation

Exhalation:
–Paired bones move into internal rotation

Question 21

What is the motion of spinal dura during inhalation and exhalation?

Answer 21

Inhalation:
–Cephalad pull on spinal dura causes sacral base to move posterosuperiorly while the apex moves toward the pubic symphysis

Exhalation:
–Caudad pull on spinal dura causes sacral base to move anteroinferiorly while the apex moves away from the pubic symphysis

Question 22

What is the motion of the SBS and paired bones during inhalation and exhalation?

Answer 22

Inhalation:

Flexion of SBS, external rotation of paired bones

Exhalation:

extension of SBS, internal rotation of paired bones

Question 23

What is the Sutherland Fulcrum? What is the origin?

Answer 23

The Sutherland Fulcrum is a floating, shifting point of balance.

It is the common origin of the three sickle-shaped agencies.

This feels much like balancing a mobile on one finger.

Question 24

What is the evidence for tenet 3?

Answer 24

• Oligodendroglial cells pulsate in culture
• Pulsatile CSF and brain motion is detectable on MR imaging
• MRI techniques needed to be developed to reduce the artifact caused by inherent motion
• Physiologic brain motion lowers the mean metabolite concentrations on proton MR spectroscopy imaging

Question 25

What is the ram’s horn development of the cerebrum? How does it related to tenet 3?

Answer 25

Tenet 3: The inherent motility of the central nervous system

Theory is that there is a coiling and uncoiling of the hemi-cerebri which changes the volume of the ventricles and leads to a pumping of the CSF

If the oligodrendroglial cells pulsate, the entire organ pulsates

Other organs have inherent motility: GI tract, heart, and that motility is not entirely due to pulsatile circulation of blood

Question 26

What is the evidence for tenet 4, the articular mobility of the cranial bones?

Answer 26

• Periostium of the inside of the skull splits into 2 layers at the suture and forms a fibrous capsule over the edge of the bone.
• Fiber bundles and sinusoidal blood vessels are in the central zone of the sutures.
• Periostium is also contiguous with the dura mater and falxes.
• Movement in the sutures is NOT the same as other joints in the body. It is more of a resiliency of living, pliant bone.
• There is small motion at the SBS which is amplified in the vault due to a vector arc.

Question 27

What is the evidence for tenet 4, the articular mobility of the cranial bones?

Answer 27

• Cranial vault is laid down in membrane in utero while the base is laid down in cartilage.
• There are 29 bones in skull, 8 in cranium, 14 in face, 7 misc: 6 ossicles, hyoid.
• More than 100 articulations in the skull collectively providing a relatively large range of motion in the cranium.

Question 28

When does ossification of the sphenoid start?

Answer 28

• The first ossification centers begin in the 8-9th week in utero.
• Much of the bone is pre-formed in cartilage.

Question 29

What is the developmental scale for the ossification of the sphenoid?

Answer 29

• At birth the bone consists of a central part (body and lesser wings) and two lateral parts (each comprising a greater wing and pterygoid process).
• By the twenty-fifth year, sphenoid and occipital bones are completely fused, and considered a symphysis. Prior to that, it is a synchondrosis.

Question 30

When does ossification of the occiput start?

Answer 30

•Ossification of the occiput commences around the 7th week of fetal life.

Question 31

What does the occiput consist of at birth?

Answer 31

•At birth the occipital bone consists of four separate parts (a basilar part, two lateral parts and a squamous part, all joined by cartilage and forming a ring around the foramen magnum. The squamous and lateral parts fuse together from the second year.

Question 32

When does the occiput finish fusing?

Answer 32

• The lateral parts fuse with the basilar part during years 3 and 4, but fusion may be delayed until the 7th year.
• 5 years per DiGiovanna

Question 33

What is the evidence for tenet 5, the involuntary movement of the sacrum in between the ilia? On what axis does this occur?

Answer 33

•Involuntary motion around a transverse axis at S2
•
•Respiratory motion occurs along a transverse axis in response to respiration. During inhalation, the lordotic curve decreases and the sacral base moves posteriorly. Exhalation increases the lordotic curve and the sacrum moves anteriorly.

Question 34

What is the inherent motion of the sacrum related to?

Answer 34

Craniosacral ‘mechanism’

Question 35

What happens during flexion of the sphenobasilar symphysis?

Answer 35

During flexion of the sphenobasilar symphysis, the sacrum counternutates or the base “nods” posteriorly.

Question 36

What happens during the extension phase of the craniosacral mechanism?

Answer 36

During the extension phase of the craniosacral mechanism, the sacrum nutates, or the base “nods” anteriorly

Question 37

What is the SBS, and what are it’s motions? How is it amplified?

Answer 37

•This is the reference point of the cranium.

• The symphysis moves into flexion and extension based on the angle at the symphysis.
• Also known as Inhalation/Exhalation phases.

•Motion at the SBS is small but it is amplified through the vault bones via a vector arc.

Question 38

Looking down on a head superiorly, the skull does what when flexed or extended?

Answer 38

Extended - skull is wider on an AP axis, narrower on a transverse axis

(face and head is narrow)

Flexed: skull is narrower on AP axis, wide on transverse axis

(Flexed = Fat, face and head is fatter)

Question 39

What are the planes of motion for the cranium?

Answer 39

• Coronal = Medial
• Sagittal = Anterior
• Cephalad = Superior
• Caudal = Inferior