Lecture 2: Osteopathic Reflexes

Question 1

What do dorsal horn neurons respond to?

Answer 1

Both visceral and somatic stimuli

Question 2

What are the specific layers of the upper layers of the spinal cord?

Answer 2

• Layer 3,4 - mechanoreceptors
• Layers 1, 5 - A delta fast pain fibers
• Layer 2 - small c fibers of slow pain

Question 3

What types of neurons are included in the lower layers?

Answer 3

• Interneurons

- Motoneuron cell bodies

Question 4

What layers are afferent fibers located?

Answer 4

End mostly in layers 1 & 5 but lots of overlap

Question 5

What % of interneurons receive input from both visceral and somatic afferents?

Answer 5

70-80%

May account for visceral pain being so diffuse and poorly located

Question 6

What is responsible for the activation of somatic muscle activity seen with visceral disturbances?

Answer 6

The overlap of afferents received by interneurons

• Visceral afferents activate sympathetic outflows and skeletal muscle motoneurons (increase tone)
• Reverse is also possible

Question 7

What affects Visceral/Somatic reflexes?

Answer 7

• Descending influences
• Affect the long-lasting excitability of the outflows by maintaining the reflex
• Sensitization of interneurons acts as an amplifier so outputs are more than expected
• May inhibit somatic and autonomic outflow

Question 8

What is the result of visceral disturbance?

Answer 8

Reflexively cause activation in the somatic musculature creating somatic dysfunction in the facilitated segment

*contributes to decompensation of homeostasis

Question 9

What is the result of somatic disturbance?

Answer 9

Reflexively alter visceral function

*contributes to decompensation of homeostasis

Question 10

What is the somatic component of disease?

Answer 10

MSK palpatory findings may correlate with visceral disturbances

Normalizing MSK component may allow normalization of autonomic outflows resulting in restoration of homeostasis

Question 11

What is sensitization?

Answer 11

When a stimulus is repeated at a rate of every second or two, response to the stimulus may continue to grow then levels out despite increase of the stimulus

Question 12

What is habituation?

Answer 12

• Opposite of sensitization
• Process of decreasing response of a neural pathway with a continuous stimulation
• Ubiquitous phenomenon

Question 13

What is facilitation (facilitated segment concept)?

Answer 13

• Habituation and Sensitization work together to keep a pool of neurons in a state of subthreshold excitation
• Less afferent stimulation is required to trigger discharge of impulses

Question 14

What causes Facilitation?

Answer 14

May be due to sustained increase in afferent input, aberrant patterns of afferent input, or charges within the affected neurons or their environment

Once established, facilitation can be sustained by normal CNS activity

Question 15

What is the nociception theory?

Answer 15

• Once a stimulus is strong enough to depolarize nociceptive pathways, impulses travel to cord then branch to multiple sites
• Results in peptide release at motoneuron level in peripheral tissues
• Peptides are important in inflammatory cascade and initiate release of prostaglandins and bradykinins
• This results in lowering nociceptor threshold thus increasing input to cord (balance between habituation and sensitization is disrupted)

Question 16

What is short term excitability?

Answer 16

• 1-2 seconds of afferent input

- Excitability lasts 90-120 seconds

Question 17

What is long term sensitization?

Answer 17

• Inputs of several minutes

- Excitability lasts hours

Question 18

What is fixation?

Answer 18

• 15-40 minutes of afferent input

- Excitability lasts days or weeks

Question 19

What is permanent excitability?

Answer 19

• Lasts forever

- Death of inhibitory interneurons

Question 20

What is allostasis?

Answer 20

Our balance of health

1. stimulus applied to tissue
2. dev’t inflammation
3. causes primary afferant sensitization
4. results in exaggerated response to noxious stimulus (hyperalgesia)
5. secondary hyperalgesia develops (central sensitization)
6. change of fxn of viscera and muscle spasm causing asymmetry and altered ROM
7. decrease in endogenous descending pathway causing loss of control of protective mechanisms aka allostasis overload

Question 21

What are the effects of somatovisceral reflexes?

Answer 21

CV - HTN, increased risk of MI
Neuro - Depression, anxiety, memory loss, decreased cognition
Immune - immunosupression, autoimmune

Question 22

somatosomatic osteopathic reflexes

Answer 22

localized somatic stimuli produce patterns of reflex response in segmentally related somatic structures

Question 23

somatovisceral osteopathic reflexes

Answer 23

localized somatic stimulation producing patterns of reflex in segmentally related visceral structures

Question 24

viscerosomatic osteopathic reflexes

Answer 24

localized visceral stimuli producing patterns of reflex response in segmentally related somatic structures

somatic pain referral due to visceral nociceptive stimuli

Question 25

viscerovisceral osteopathic reflexes

Answer 25

localized visceral stimuli producing patterns of reflex response in segmentally related visceral structures

Question 26

withdrawl reflex

Answer 26

type of somatosomatic reflex

noxious stimulus applied to somatic structure

Question 27

myotatic response

Answer 27

type of somatosomatic reflex

stretch receptor stimulated and stretched muscle fires while antagonist is inhibited

Question 28

What type of reflex is abdominal distention after eating?

Answer 28

viscerovisceral - distention of gut results in contraction of stomach muscle

why spinal cord injured patients are able to digest food

Question 29

Somatocardiac reflex

Answer 29

nociceptive somatic stimuli result in elevation of HR and BP

Question 30

Somatogastric reflex

Answer 30

nociceptive somatic stimuli results in inhibition of peristalsis in stomach

Question 31

Somatoadrenal reflex

Answer 31

nociceptive somatic stimuli results in release of catecholamines from adrenal medulla

Question 32

What is important about the vagus nerve?

Answer 32

it’s 80-90% sensory!

All visceral nerves contain sensory fibers

Question 33

Where are the cell bodies of sensory neurons located?

Answer 33

Dorsal root ganglion - create complex communication network connecting visceral and somatic systems

Question 34

What are chapman’s reflexes?

Answer 34

Group of palpable points occurring in predictable locations on the anterior and posterior surfaces of the body that are considered to be reflections of visceral dysfunction or disease

Question 35

What are the components of Chapman’s reflexes?

Answer 35

1. Viscerosomatic reflex of both diagnostic and treatment value
2. Gangliform contraction that blocks lymphatic drainage and causes SNS dysfunction (neurolymphatic)
3. A consistent reproducible series of points both anterior and posterior related to specific organs or conditions

Question 36

What might you palpate at one of Chapman’s points?

Answer 36

Small, smooth, firm nodule approximately 2-3 mm in diameter on deep fascia or periosteum

Question 37

How to you treat an abnormality at a Chapman’s point

Answer 37

Once found and isolated, apply gentle but firm pressure, move tip of finger in circular fashion in attempt to flatten the mass (10-30 seconds)

Stop when the mass disappears or the patient can no longer tolerate the procedure

Question 38

What might the patient experience during treatment?

Answer 38

A deep, disagreeable pain that they usually don’t know is there otherwise

Pinpoint, sharp, and non-radiating pain located directly under the physician’s fingertip

Question 39

Contraindications to Chapman’s treatment

Answer 39

• have critical airway, breathing, or circulation problems
• no consent
• relative contraindications: fracture, cancer, and other patient instability