4. 1. Circulatory impairment :arterial or venous
thrombosis, thrombophlebitis.
2. Stimulation over the carotid sinus.
3. Stimulation across the heart: especially if patient has
pacemaker.
4. Pregnancy.
5. Seizure disorder.
6. Fresh fracture.
7. Active hemorrhage.
8. Malignancy.
9. Decreased sensation—direct current can cause burns
(electrochemical).
10. Atrophic skin.
11. Patients inability to report stimulation-induced pain.
12. Known allergies to gel or pads.
6. 1. Stimulates nerve fibers for the
symptomatic relief of pain.
2. Uses a pocket-size programmable device
to apply an electrical signal through lead
wires and electrodes attached to the
patient’s skin.
3. Electrode placement is subjective.
Typically placed over peripheral nerve distribution.
Locations can be distal or proximal to pain site.
7. 1. Placebo effect is 30–35%.
2. Based on the Gate Control Theory by Melzack
and Wall (1965):
Pain signals can be blocked at the spinal cord before
they are transmitted to the brain. TENS stimulates
large Ia myelinated afferent nerve fibers that
stimulate the substantia gelatinosa in the spinal
cord, closing the gate on pain transmission to the
thalamus.
3. Release of endogenous opioids via TENS
Cheng and Pomerantz (1979)—demonstrated
that pain relief produced at 4 Hz stimulation
(low frequency) was blocked by Naloxone;
pain relief induced at 200 Hz was not blocked
by naloxone .
8. Attempts to account for mechanisms by
which other cutaneous stimuli and
emotional states alter the level of
pain.
9. Treatment time with TENS is normally 30
minutes to 1 hour per session with a
maximum of 2 hours per session, for a
total of 8 hours per day.
The treatments are continued for 3 weeks
and gradually reduced over 8–12 weeks.
Patients may report discomfort or skin
irritation if the intensity is too high.
Skin irritation can be resolved if the
electrode positions are shifted or if a
different conducting gel is used.
Electrode shifting can increase current
intensities to uncomfortable levels.
10. Conventional (IF- currents)
1. High-frequency, low-intensity stimulation:
most effective type of stimulation.
2. Amplitude is adjusted to produce minimal
sensory discomfort.
3. Pain relief begins in 10–15 minutes and
stops shortly after removing stimulation.
4. Useful for neuropathic pain.
5. Duration of treatment is 30 minutes to
hours.
11. Low frequency, high intensity stimulation (DD-
currents).
1. Amplitude high enough to produce muscle
contraction.
2. Onset of pain relief can be delayed several hours
3. Pain relief persists hours after removing
stimulation.
4. Useful for acute musculoskeletal conditions.
5. Treatment sessions last 30–60 minutes.
Hyperstimulation
1. High frequency, high intensity stimulation.
2. It is considered that this mode stimulates C-
fibers causing counter-irritation.
3. Rarely tolerated more than 15–30 minutes.
12. Pulse or burst mode
◦ High frequency stimulation bursts at
low frequency intervals
◦ Delayed onset of pain relief
◦ Treatment can range 30–60 minutes
Modulated
◦ Impulses vary in intensity and
frequency
◦ Attempts to avoid neuro-habituation
14. Consists of trans-cutaneous electrical
stimulation for muscles with or without intact
peripheral nerve stimulation, or central
control.
When the electrical stimulation is used to
provide functional use of paretic muscles, it is
called FES (functional electrical stimulation)
or FNS (functional neuromuscular stimulation).
Multiple muscles can be activated in a
coordinated fashion through the use of
electrical stimulation to attain certain
functional goals (ambulation, transfers).
15. 1. Maintains muscle mass after immobilization.
2. Increases muscle bulk
3. Prevents complications from immobility such
as deep vein thrombosis (DVT), osteoporosis
and fractures
4. Strengthens muscles—effects have been
noted even without voluntary muscle action.
5. Changes of type II muscle fibers into type I
fibers are temporarily noted with the
treatments.
6. Increases ROM or maintains it.
7. Provides feedback to enhance voluntary muscle
control (muscle reeducation).
8. Inhibits spasticity and muscle spasm.
9. Can be used for orthotic training and
functional movement.
16. Open-loop system:
◦ Manual feedback.
◦ Most units are open-loop type
◦ The user observes the results of the stimulation
and based on this adjusts the stimulation intensity.
◦ Each cycle of activity starts with the use of manually
activating switches that send signals to control the
unit.
Closed-loop system:
◦ Control unit depends on movement sensors that
send signals from the patient’s body as results
are obtained.
◦ Stimulation is adjusted to improve the
programmed result.
◦ Lack of effective sensors may pose a problem.
◦ Advantages include correction of unexpected
problems such as muscle spasms and fatigue.