Pathophysiology Flashcards
What is the pathophysiology of CRPS?
Inflammation - upregulation of inflammatory markers leads to sensitization of nerves eventually leads to central sensitization which makes it harder to treat.
What is the activity of mu-2?
associated with respiratory depression, decreased GI motility, miosis, euphoria and physical dependence.
What is the activity of Mu-1?
supraspinal analgesia and dependence
What is the activity of opioids at kappa receptors?
spinal analgesia, miosis, sedation
What is the activity of opioids at the delta receptors?
euphoria and physical dependence
EMG finding of radiation brachial plexopathy
Myokomia
Loss of lat/medial antebrachial cutaneous nerves
Neurogenic motor units
Changes in sensory nerve action potential
EMG finding of radiculopathy
Paraspinal fibrillations
Neurogenic motor units
Normal sensory nerve AP
EMG finding of myopathy
Small motor units potential
Increased recruitment
EMG finding of EARLY radiculopathy
Reduced recruitment
Normal motor units potential
Normal sensory nerve AP
EMG finding of motor neuron disease
Diffuse fasciculation potentials
Scattered fibrillation potentials
Complex motor units
Units of measurement for Xrays
Annual max permissable radiation measures in rem or sievert. 1 Sy=100 rem
Absorbed total ionizing dose is measured in…
Rad or Gray. 1 Gray = 100rad
Total effective dose equivalent on a soft tissue mass is calculated in…
mRem (Roentgen equivalent man) or Sievert
1 Roentgen = 1 rad = 1 rem
Which nerve block diagnoses pain from TMJ capsule
Auriculotemporal nerve
> 10Gy doses can cause…
dry desquamation, telangiectasia, dermal atrophy
Radiation dosing comparison
Interventional procedures x10 > Angiography 10x > GI fluoroscopy/CT scanning
RF of chronic post surgical pain
5x RF
- preop pain
- preop pain in another location
- feeling of inability to cope psychologically with stresses in the last 6 months
- > 2 symptoms of sleeping d/o, taking sleeping pills, exhaustion, dizziness, tachycardia, feeling misunderstood, trembling hands
- poor post op pain control
Golfers elbow (medial epicondylitis)
Pain on supination and elbow extension
Cubital tunnel syndrome
Numb and tingling in ringer and small finger.
Pain and weak grip
Infant myelination
Occurs at mid gestation and continues for 2 decades
Modic changes of vertebrae and end plates
- Modic 1: BM inflammation, edema -> MRI T1 low signal, T2 high
- Modic 2: Normal BM conversion to yellow fatty BM due to BM ischemia -> T1 high signal, T2 iso to high signal
- Modic 2: Subchondral bony sclerosis -> T1 and T2 Low signal
How much scattered radiation is absorbed by lead apron?
90-95%
How thick should lead aprons be?
0.5-1mm
How thick should thyroid shield be?
0.5mm
What is the oral bioavailability of morphine?
10-45%
Epidural morphine has bi modal distribution resulting in..
another peal analgesia and respiratory depression therefore not used in outpatient
What is the physical finding in medial epicondylitis?
Pain on supination and elbow extension
What is the PE of cubital tunnel?
tingling in ring and small finger when elbow is bent
What is associated with tight tensor fasica lata?
Pain and tightness in outer knee and IT band when walking uphill.
Tight quadricep tendon results in…
Pain in patella and distal thigh.
Tight iliopsoas result in …
Sudden sharpness in hip and pelvis after trauma
Piriformis syndrome result in…
Dull ache in buttock, pain in calf, foot. Pain with walking incline and prolonged sitting
Suprascapular nerve innervated…
supraspinatus, infraspinatus
L4 nerve root is…
Weak dorsiflextion, loss of patella reflex
L3 nerve root is…
Weak of leg extension (quadriceps), sensory loss of medial aspect of femur
L5 nerve root is…
Weak dorsiflexion of big toe, loss of sensation of dorsum of foot
S1 nerve root is…
Weak of plantaflexion, sensory loss of lateral foot
Tarsal tunnel
Tibial sensory and motor due to fracture leading to ischemia of nerve
Dural sac ends…
S2-3 in adults
S4 in children
Which NT acts on NMDA receptor?
Aspartate and glutamate
Hemicrania continua diagnostic criteria
- Pain >3 months
2/4 of below
- unilateral pain
- continuous pain
- autonomic features
- moderate intensity with severe exacerbations
Context sensitive half time means…
the amount of time for blood/plasma concentration to decrease by 50% after stopping the constant infusion.
Biological half life=Elimination half life means
Time for concentration of substance in plasma to lose 50% of the radiological, pharmacological and physiological activity
Tic convulsif is..
Trigeminal neuralgia with involuntary contractions of face
Osteoporosis diagnosis on DEXA scan
more than -2.5
- 1 to -2.5 is osteopenia
- 1 and above is normal
Chronic compartment syndrome
Sudden pain with exercise with tingling
Pain subsides at rest
Changes are reversible, muscles can be normal at rest
Main opioid receptor for analgesia
mu-1
Where is H reflex found
-Soleus muscles and forearm flexor muscles
-Delayed/absent H reflex can signify S1
radiculopathy
-Disappearance of H reflex is known as anti-dromic collision along motor neurons
Reduced active ROM of ABduction of shoulder BUT NORMAL passive ROM
Subacromial bursitis
Vs frozen shoulder which will have reduced passive and active ROM
Horners syndrome can be caused by
carotid artery dissection
diagnosed on MRA neck and head
Glossopharyngeal neuralgia is associated with
Bradycardia and syncope due to vagal stimulation
- Diagnosed by application of 10% cocaine over trigger zone with resolution
- Pain triggered by swallowing and coughing
- Posterior 1/3 of tongue
- Symptom arise in throat and felt in ear
Examples of Stochastic effects of radiation are
Genetic defects and cancer
Compressive lesion findings on needle examination
Starting from earliest:
- reduced recruitment
- dev of fibrillation potentials
- Complex motor unit potential
- Large motor unit potential
Thoracic outlet syndrom involves which nerve roots?
- C8-T1 in 90% cases
2. C5-7 less common
Innervation of annulus fibrosus
- sinovertebral nerves
- gray rami communicantes
- lumbar sympathetic trunk
A delta and C fibers terminate in which laminae of grey matter
laminae I and II
Which receptor senses a steady sensation on the skin?
Merkel’s disk - mechanoreceptors found in basal epidermis and hair follicles
What is the cause of patellofemoral pain syndrome?
it is thought to be due to overloading the knees extensor mechanism
Mechanism of visceral hyperalgesia
viscerosomatic convergence
Wide dynamic range neurons
Include A and C fibers
