Neurodynamics (Guest Lecture) Flashcards
Describe the purpose of pain
Pain acts as a “smoke alarm”
It allows the brain to conclude that there is actual or potential damage and that action is required
Give an example that show there is not a direct relationship between pain and dysfunction
Stubbing your toe
Term: Study and relationship of the nervous system mechanics and physiology
Neurodynamics
Descibe how the neurosystem adapts to movement
It just move and stretch all while performing complex eletrochemical processes. Lack of adaptation would result in injury
Give 2 examples of the adaptability of the nervous system
SC lengthens 7-10 cm or 3-5 inches with flexion
The median nerve increases it’s length by 20% from wrist/elbow flexion to extension
5 Points of Greater than Normal Nerve Tension
- C6
- T6** (due to increased lig attachment at SC)
- L4
- Posterior Knee
- Anterior Elbow
Term: Point where there is no movement of the nervous system in relation to the tissue/dura interface
Tension point
CNS Protective Layers
Dura mater
Arachnoid mater
Pia mater
PNS Protective Layers (out to in)
Mesoneurium
Epineurium
Perineurium
Endoneurium
Describe how the connective tissues supporting the nervous system can cause sx
The connective tissues are innervated, inflammation and/or ischemia in these tissues stimulates their free nerve endings resulting in sx
Structure: nerve cytoplasm that acts as a transport system being nourishment to cells
Axoplasm
Structure: movement and circulation dependent, 3-5x thicker than water
Axoplasm
Describe the nervous systems need for blood
They are blood suckers! While they make up 7% of our BM they use 25% of our Q
Describe the effect of elongation on BF to the nervous system
At 8% elongation BF can become compromised which can lead to nervous tissue damage
7 Nerve Pain Generators
- Blood Flow
- Axoplasmic Flow
- Double Crush
- Connective Tissue
- Abnormal Impulse Generating Sites (AIGS)
- Substance P
- Surrounding Tissue Injury
Descibe the amount of compression need to stop BF and the affect on nerves
30 mmHg of pressure can occlude BF resulting in a swollen nerve
Term: Movement dependent
Thixotropic
Decribe the flow of Axoplasm
Axoplasm moves 100-400 mm a day. Immobilization or ischemia can slow or even stop flow. This flow is movement dependent (thisotropic)
Term: Experience symptoms distal to the nerve injury
Double crush
ex. hitting your funny bone
Term: Experiencing symptoms proximal to the nerve injury
Reverse double crush
ex. CTS producing neck/shld pain
Describe how double crush/reverse double crush is possible
Because the nervous system is a closed system injury in one area of a nerve can lead to pathology in other nerve sites
Describe how connective tissue can generate nerve pain
CT makes up 50% of the diameter of a nerve and it is highly innervated (free nerve endings, pacinian corpuscles) as well as surrounded by unmyelinated fibers containing pain neuropeptitides
Describe AIGS
Axons transmit messages, the ion channels used to transmit an AP typically are recycled every 2 days. However, if there is vascular injury these channels can get stuck in the axolemma and fire at random in both directions. These miss fires can manifest as N/T, burning, pressure, etc. Without axoplasm flow this can persist.
Describe how Substance P generates nerve pain
When a nerve processes information abnormally, substance P and excitatory amino acids are released in excess. This stimulates glial cells to release inflammatory agents (NO, cytokines, prostaglandins) which inturn stimulate further release of substance P
