Facilitation Flashcards
Definition of facilitation
maintenance of pool of neurons in a state of partial or sub threshold excitation
less afferent stimulation required to trigger discharge of impulses
Can be sustained by normal CNS activity
Segmental facilitation
facilitation at individual spinal level
Spinal reflex parts
afferent limb - sensory input
central limb - spinal pathway
Efferent limb - motor pathway
Sensitized interneurons
abnormal and steady sensory stimulus -> sensitive to stimulus
increased/exaggerated output to initiating site
Once sensitized state established, segment is facilitated
any continuous sensitizing input or normal input will maintain abnormal condition
Facilitation causing SD
- abnormal and continuous sensory input, e.g. overstretched muscle spindle, sensitizes interneurons in spinal cord at corresponding level
- reflex occurs, muscle tension produced -> restricted ROM and tenderness to palpation
- Prolonged muscle tension -> continuation of sensitizing input and maintenance of facilitated segment
- Muscle tension at initiation site -> nociceptor activation in neighboring areas, release vasoactive substances (bradykinins, serotonin, histamines, potassium, PGs, substance P, leukotrienes) -> vasodilation and tissue texture changes
- abnormal and continuous sensory input -> paraspinal muscle spasm. Facilitated interneurons may cause exaggerated motor output via dorsal rami -> increased muscle tension in deep paraspinal muscles
- > increased muscle tension, rotation and sidebending -> asymmetry
Viscero-somatic reflex
abnormal sensory input from visceral receptors into spinal cord -> segmental facilitation
Normal sensory input from general afferents become amplified at sensitized interneurons -> exaggerated motor response
-> increase in paraspinal tension, tenderness and pain elicited at corresponding region
Increased muscle tension in paraspinal m -> rotate and sidebend so SD present
Somato-visceral reflex
Somatic stimuli produce reflex response in segmentally related viscera
Trigger point in right pectoralis major muscle, 5th - 6th ribs, medial to nipple line -> SVT
Vagus parasympathetics
All viscera above diaphragm
GI through splenic flexure
kidneys, upper ureter
Ovaries and testes
Pelvic splanchnic parasympathetics
colon distal to splenic flexure
lower ureter and bladder
Sympathetics
T1-4 - head and neck
T1-5 heart
T2-7 lungs
T5-9 GI before ligament of trietz (divides duodenum and jejunum
T10-11 GI jejunum through splenic flexure
T12-L2 GI distal to splenic flexure
T2-8 upper extremities
No sympathetics from L3-L5 - spinal cord terminates between L1-2
Rib raising
normalize (decrease) sympathetic activity
Improve lymphatic return
Encourage maximum inhalation and provoke more effective negative intrathoracic pressure
Indications: Visceral dysfunction Decreased rib excursion Lymphatic congestion Fever Paraspinal muscle spasm
Contra:
Spinal or rib fracture
Recent spinal surgery
Soft tissue paraspinal inhibition
normalize (decrease) sympathetic activity - ileus prevention
Upper lumbar L1-L2 sympathetic ganglia
direct paraspinal pressure on erector spinae mass -> same autonomic effects as rib raising
Celiac ganglion, SM, IM releases
normalize (decrease) sympathetic activity
midline abdominal pressure over ganglia reduces hypersympathetic activity
pressure applied until fascial release palpable
Indications:
Gi dysfunction
Pelvic dysfunction
Contra:
Aortic aneursym
Open surgical wound
Treatment of chapman reflexes
decrease sympathetic tone to associated visceral tissues
soft circular manipulation over the point itself
posterior Chapman’s points rubbery, similar to classic viscerosomatic reflex
Cervical paraspinal sympathetic ganglia
Superior - C1-3
Middle C6-C7
Inferior C7-T1
