Electrotherapy and Pain Modulation Flashcards
1
Q
What are the levels of physiologic response (4)
A
- Cellular
- Tissue
- Segmental
- Systemic
2
Q
What are the cellular level responses to electrotherapy (5)
A
- Excitation of excitable cell membranes
- Changes in cell membrane permeability
- Protein synthesis
- Stimulation of fibroblasts and osteoblasts
- Modification of microcirculation
3
Q
What cell membranes are excited by electrotherapy (2)
A
- Nerve
2. Muscle
4
Q
What are the tissue level responses to electrotherapy (3)
A
- Skeletal muscle contraction
- Smooth muscle contraction
- Tissue regeneration
5
Q
True or False:
Tissue level responses to electrotherapy require multiple cellular events
A
True
6
Q
What are the segmental level responses to electrotherapy (5)
A
- Modification of joint mobility
- Modification of muscle contractility
- Muscle pumping action to change circulation and lymphatic drainage
- An alteration of microvasculature not associated with muscle pumping
- Increased movement of charged proteins into lymphatics resulting in fluid moving centrally
7
Q
What are the systemic response to electrotherapy (3)
A
- Analgesic effects as endogenous pain suppressors are released
- Analgesic effects from the stimulation of certain neurotransmitters
- Stimulate spinal gate
8
Q
What are the effects of electrical stimulation (3)
A
- Nerve depolarization
- Muscle depolarization
- Ionic effects
9
Q
What has a slightly higher resting membrane potential nerves or muscles
A
Muscles
10
Q
True or False:
The membrane of cells has differential permeability to different electrically charged ions
A
True
11
Q
Is K+ easily or slightly permeable to the membrane
A
Easily permeable
12
Q
Is Na+ easily or slightly permeable to the membrane
A
Slightly permeable
13
Q
True or False:
The membrane is impermeable to large negatively charged protein and phosphates (anions)
A
True
14
Q
True or False:
There are a large number of anions trapped inside the cell
A
True
15
Q
True or False:
Depolarizing something in the middle will cause depolarization on both directions
A
True
16
Q
Which way does the Na+/K+ pump move Na+ and K+ in relation to the cell
A
Na+ out
K+ in
17
Q
Where is Na+ in higher concentration
A
Fluid surrounding the cell
18
Q
Where is K+ and anions in higher concentration
A
Inside the cells
19
Q
What is the resting membrane potential for muscle
A
-90 mV
20
Q
What is the resting membrane potential for peripheral nerves
A
-70 mV
21
Q
What maintains the negative resting membrane potential
A
The Na+/K+ pump moving 3 Na+ out and 2 K+ in resulting in a negative charge
22
Q
True or False:
Larger diameter nerve fibers conduct the action potential faster
A
True
23
Q
How fast do A alpha motor nerves carry APs
A
60-120 m/sec
24
Q
How fast do A gamma and A delta nerves carry APs
A
12-30 m/sec
25
True or False:
| Myelin makes the AP conduct faster
True
26
What is the AP jumping from node to node called
Saltatory conduction
27
True or False:
| Most nerves in humans are mixed nerves leading to different nerve fibers firing at different rates
True
28
Where is the cell body and axon located in motor nerves
Cell body: Ventral horn or brainstem motor nuclei
| Axon: Terminate on muscle
29
Where is the cell body and axon located in sensory nerves
Cell body: Dorsal root ganglion or cranial nerves sensory nuclei
Axon: 50% end as free nerve endings and 50% are specialized sensory receptors
30
What are the A alpha nerve diameter, conduction velocity, and type of nerve fiber (3)
1. 12-20, 72-120, Muscle spindle primary afferent
2. 12-20, 72-120, Golgi tendon organ afferent
3. 12-20, 72-120, Skeletal muscle efferent
31
What are the A beta nerve diameter, conduction velocity, and type of nerve fiber (2)
1. 6-12, 36-72, Touch pressure receptor afferent
| 2. 5-12, 20-72, Muscle spindle secondary afferent
32
What are the A gamma nerve diameter, conduction velocity, and type of nerve fiber (1)
1. 2-8, 12-48, Muscle spindle efferent
33
What are the A delta nerve diameter, conduction velocity, and type of nerve fiber (1)
1. 1-5, 6-30, Pain temperature afferent
34
What are the B nerve diameter, conduction velocity, and type of nerve fiber (1)
1. Less than 3, 2-18, Preganglionic autonomic efferent
35
What are the C nerve diameter, conduction velocity, and type of nerve fiber (2)
1. Less than 1, Less than 2, Pain temperature afferent
| 2. Less than 1, Less than 2, Postganglionic efferent
36
What are Ia nerve diameter, conduction velocity, and type of nerve fiber (1)
1. 12-20, 72-120, Muscle spindle primary afferent
37
What are Ib nerve diameter, conduction velocity, and type of nerve fiber (2)
1. 12-20, 72-120, Golgi tendon organ afferent
| 2. 12-20, 72-120, Skeletal muscle efferent
38
What are II nerve diameter, conduction velocity, and type of nerve fiber (3)
1. 6-12, 36-72, Touch pressure receptor afferent
2. 5-12, 20-72, Muscle spindle secondary afferent
3. 2-8, 12-48, Muscle spindle efferent
39
What are III nerve diameter, conduction velocity, and type of nerve fiber (2)
1. 1-5, 6-30, Pain temperature afferent
| 2. Less than 3, 2-18, Preganglionic autonomic efferent
40
What are IV nerve diameter, conduction velocity, and type of nerve fiber (2)
1. Less than 1, Less than 2, Pain temperature afferent
| 2. Less than 1, Less than 2, Postganglionic efferent
41
What does the Gasser scheme name
Peripheral nerve fibers
42
What does Lloyd scheme name
Sensory fibers only
43
What is the strength duration curve
Graphic representation of minimum combination of current strength and pulse duration needed to depolarize that nerve
44
What do lower current amplitudes and shorter pulse durations depolarize
Sensory nerves (A beta and A delta)
45
What do higher current amplitudes and longer pulse durations depolarize
Motor nerves (A alpah and A gamma)
46
What do higher yet current amplitudes and longer pulse durations depolarize
Pain transmitting C fibers
47
True or False:
| You feel the electrical current before you see movement
True
48
What is sub-threshold
Amplitude duration below curve for particular nerve
49
What is threshold stimulation
Amplitude and duration on the curve
50
What is supra-threshold
Amplitude and duration above the curve
51
True or False:
| The peripheral nerve membrane is more excitable than the muscle membrane
True
52
What is the minimum current amplitude with a very long pulse duration required to produce an action potential called
Rheobase
53
What is the minimum duration it takes to stimulate that tissue twice the rheobase amplitude called
Chronaxie
54
What is rheobase dependent on
Current amplitude
55
What is chronaxie dependent on
Time/duration
56
What is all or none response
Once threshold is achieved nerve fiber fires
57
What is accommodation
If stimulus is too slow nerve can adjust threshold level
58
What are the 2 types of AP propagation
1. Orthodromic
| 2. Antidromic
59
What is orthodromic propagation
Normal physiological stimulation where the AP propagates one way only
60
What is antidromic propagation
AP propagated both ways
61
What controls peripheral nerve axon recruitment
Intensity
62
What does a current that is applied at an intensity and duration just strong enough to reach threshold stimulate in a mixed nerve
Large superficial fibers
63
What does an increased current intensity now stimulate in a mixed nerve
Medium sized superficial and deeper large sized fibers
64
What does further increasing current amplitude now stimulate in a mixed nerve
Small superficial, medium deeper, and large deepest fibers
65
What is TENS used for
Pain modulation
66
What can selective stimulation of A beta fibers do
Block pain transmission in the spinal cord via the gate control theory
67
What are the parameters for E-stim trancutaneously (conventional)
Short pulse duration (50-80), pulse frequencies 100-150, and low current amplitude (cause tingling)
68
How long will conventional TENS block pain
Only as long as the stimulation is on
69
True or False:
| Conventional TENS can be used 24 hours a day
True
70
How do you control for adaption (2)
1. Modulate rate
| 2. Modulate width
71
What are the parameters for low rate or acupuncture like TENS
Frequencies of 2-10, long pulse duration (100-200), and higher current amplitude (visible contraction)
72
How long will acupuncture like TENS control pain after 20-30 minutes of treatment
4-5 hours
73
How does acupuncture like TENS control pain for 4-5 hours
By stimulating the endogenous opioid system
74
What is the half life of endogenous opiates
4.5 hours
75
What fibers does acupuncture like TENS stimulate (3)
1. A delta nociceptive
2. A alpha
3. A beta
76
What are the parameters of noxious intensity TENS
Short duration stimulation (less than a minute), can use low (1-5) or high frequencies (80-110), pulse duration up to 1 sec, and amplitude 2 times motor threshold
77
What is the intent of noxious intensity TENS
Stimulate C-fibers
78
What is the motor threshold
When you see the muscle twitch
79
What fibers does noxious intensity TENS stimulate
A delta, C fibers, A alpha, and A beta
80
True or False:
| Noxious intensity TENS uses opioid mediated and nonopioid mediated analgesia
True
81
What does noxious intensity TENS mediate in the cord
Serotonin and noradrenaline
82
Where does noxious intensity TENS mediate muscarinic
Supraspinally
83
What does burst mode TENS work like
Low frequency TENS
84
How is the stimulation delivered in burst mode TENS
Bursts or packages of 10 pulses
85
What is the pulse duration of burst mode TENS
100-300 pps
86
What types of nerves does interferential current depolarize
Sensory and motor nerve
87
What are the therapeutic effects of IFC (3)
1. Increase pain threshold
2. Muscle contraction
3. Muscle pumping
88
How does IFC work
Stimulator imparts 2 different currents into the body and the currents interfer giving you a beat current which is the difference between frequencies.
89
True or False:
| The beat frequency can be changed to get pretty much any effect you want
True
90
What is the pulse frequency of IFC for pain management
50-120 pps
91
What neurons do you want to stimulate to modulate pain with IFC
Large diameter afferent neurons
92
What is the pulse frequency of IFC for muscle contraction
20-50 pps
93
What is the pulse frequency of IFC for acutism pain relief
1 pps
94
True or False:
| 30 pps gives a smooth tetanic contraction when using IFC
True
95
What are the indications for IFC (2)
1. Pain of known origin
| 2. Possibly for muscle exercise to increase blood flow, muscle relaxation, and edema reduction
96
What are the therapeutic purposes for high voltage pulsed current (3)
1. Sensory TENS pain management
2. Muscle contraction
3. Motor TENS pain relief
97
What is the pulse frequency for HVPC sensory TENS pain management
80-120 pps
98
What is the pulse frequency for HVPC muscle contraction
30-60 pps
99
What is the pulse frequency for HVPC motor TENS pain relief
2-4 pps
100
What does HVPC sensory TENS pain management stimulate
1. Large diameter afferent neurons
| 2. Activate spinal gate
101
What does HVPC motor TENS pain relief stimulate
Endorphin descending loop
102
True or False:
| E-stim can activate the spinal gate to decrease pain
True
103
How does E-stim activate the spinal gate to decrease pain
Stimulate A-beta fibers which closes the spinal gate by competing with A-delta and C-fibers
104
What is AC current
An alternating sinusoidal curve
105
What is DC current
Current that stays on the same side of the line
106
How does AC current cause muscle contraction
Stimulates the alpha motor neuron
107
How does DC current cause muscle contraction
Stimulates the muscle its self
108
What type of contraction does AC current produce
Smooth tetanic contraction
109
What type of contraction does DC current produce
A twitch
110
Why are A-beta fibers the first fibers stimulated
The are small diameter myelinated fibers
111
Why is a shorter phase duration more comfortable
The electric current is flowing in one direction for a longer time
112
How do you stimulate the ascending and descending endorphin loops
By stimulating the A-delta and C-fibers
113
Does E-stim directly stimulate receptors
No it stimulates the nerve attached to the receptor
