When Giles performed his study on the IVFs where did he measure the IVF?
On the medial border(which was smaller) and the nerve root-ganglion complex(which was larger)
When Crelin measured the IVFs in his study where did he measure?
Measured the lateral border of the IVF relative to the exiting spinal nerve
In regards to nerve impingement and IVF space what are the 3 main points that differ between crelin and giles?
Crelin-measured lateral border, x-section of nerve to IVF left 5-6x reserve space, distance of nerve to IVF never less thn 4mm
Giles- measured entire length of the interpedicular canal zone, x-section was a smaller reserve(3.3-4.6x), distance of nerve to IVF 0.4-0.9mm
What was Giles conclusion to his measurements revealing much smaller clearances?
“compressive irritation…may arise, especially should there be intervertebral disc and/or osteophytic projection into the intervertebral canals.”
Are subluxations likely to cause severe compression signs?
A patient with nerve root compression(severe or mild) is this likely to do to a subluxation?
Neither are likely to be due to subluxations…keep looking for diagnoses
Is radiating pain due to irritated nerve roots?
Usually not and nerve tension tests with be negative
What is radiating pain usually due to?
Somatic referred phenomenon from irritated joint structures
What is palmers “too much nerve energy”?
May be increased action potentials from the irritated joints irritating the CNS
What are the symptoms of nerve root irritation?
Patients with dermatomal pain/paresthesia and positive nerve tension test
When thinking of nerve root irritation what are the first things that you should be thinking of?
chemical/mechanical irritation from- disc herniation osteophytes, stenosis, and tumors
When should subluxations and NR irritation be considered?
if other more probable diagnoses do not seem likely and subluxations are present, the the radicular syndrome may be associated with the subluxation
What are possible ways that a subluxation could cause NR irritation?
The joint dysfuntion may be associated with chemical irritatns from the discv,, from local inflammation(H+ ions), or nerve root adhesion
What is the differential diagnosis for radicular from deep referred pain? symptoms(from history)
Radicular- Dermatomal pain Pain may be sharp or electrical Dermatomal paresthesia Reports of subjective numbness or weakness Deep referred- Diffuse pain less likely to cross the knee(elbow)
What is the DDX radicular from referred? signs(from physical)
Positive tension tests suggest NR irritation
Neurological deficits suggest compression/cell damage
Negative tension tests
No neuro defiits
Thinking of the co activation model what does manipulation do?
It acts as a “counter-irritant” closing the pain gate
When manipulation is acting as a counter irritant what is it ding?
It activates multiple pools of tissue r/c’s composed of both mechano and nociceptors which may help block central sensitization
What are the 3 things that Wycke’s mechanreceptors do?
- Reflexogenic effects
- Postural effects
- Pain suppression
What are the reflexogenic effects of Wycke’s receptors?
Project to fusimotor fibers(gamma system)
Affect muscle tone and stretch excitability
Affect muscle above, below, and contralaterally
What are the postural effects of Wycke’s receptors?
Type1 mechanorecepetors project paracentral and parietal centers influencing postural and kinesthetic perception
What is the pain suppression aspect of wycke’s mechanreceptors?
Stimulation of mechanoreceptors inhibit pain(phasic response)
Observations have been recorded be EMG whee local muscular hypertonicity(spasm) in symptomatic patients was largely abolished immediately after an adjustment. Who made these observations?
What are teh hypothesis reached by Lehman, Vernon, and McGill?
manipulation may “interrupt the pain-spasm cycle by down-regulating the central sensitization”
What was Korr’s hypothesis?
- Manipulation causes a barrage of impulses from the muscle spindle afferents
- Which inhibits the “gain” within the system, restoring it back to normal so the muscle was not so predisposed to spasm
- This happens though an as yet undetermined pathway
What was concluded from Wycke’s study on cats?
Distraction of the cervical facet joints in the cat produced simultaneous onset on EMG activity in selected forelimb muscle
-He attributes this to capsule mechanoreceptor reflex response
What were the results of Herzogs study?
(As predicted) Adjustments produced EMG activity in targeted muscles. Slower impulses did not create this response
What were the results of leiber’s study? Grade I vs. Grade IV mobilizations
Grade IV mobilizations resulted in an increase isometric strength of the lower traps compared to a grade I mobilization
What were the results of Yery’s study with hip flexors?
There was a significant increase in hip flexor strength(14%) in the study group(grade IV mobilizations) based on 5 pre and post test isometric repetitions measured on an isokinetic machine
What is Herzog’s speculation?
Adjusting appears to relax muscles and activate hypotonic muscle “converge to normal”
What did sterling find with cervical spine mobilization?
- Activated deep flexor activity
- Decreased SCM EMG activity
What can poor proprioceptive information lead to?
faulty coordination and control
What does dynamic loading require? Otherwise what results?
Good proprioceptive input and quick, coordinated muscle response
What is Revel’s test?
The blinded person with a laser strapped to their head and pointing the laser at a target…repositioning errors are observed
Where is the body are the highest density of mechanoreceptors?
- Upper cervicals
- Sacroiliac joints
- Foot and ankle