The cranial model: PRM, strain patterns and techniques
The primary respiratory mechanism
Five proposed components:
- Inherent motion of the brain and spinal cord.
- Fluctuation of cerebrospinal fluid.
- Mobility of the dural membranes inside the skull and spine.
- Motion of the cranial bones.
- Involuntary motion of the sacrum between the ilia.
Board review keys the cranial rhythmic impulse at 10 to 14 cycles a minute; other texts quote somewhat wider or lower ranges, and no rate is a validated diagnostic test. The dura attaches firmly at the foramen magnum and upper cervical spine and ends around S2, which is why the model links the cranium and the sacrum through a respiratory axis at S2.
The rest of this guide is for founders
Founders get every guide, endless cases with an AI tutor, and Anki export of their misses. Here is what is inside:
- The primary respiratory mechanism
- Flexion and extension
- Strain patterns
- Holds and techniques
- Infant head shape
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