TEST 14

Low Rate TENS

(1) *Low rate/acupuncture-like* (frequency) or motor-level TENS has been equated with acupuncture in its mechanism of pain relief. Motor-level TENS is commonly used to treat patients with chronic pain. (2) This mode is *more vigorous* and is used to treat *sub-acute or chronic pain*. Also, used for *trigger points.* (3) Pain reduction attributed to endogenous opiate (endorphin release) inhibitory mechanisms or motor level pain modulation. According to this theory, this type of treatment raises the level of endorphins in the cerebral spinal fluid (Sjoglund and Eriksson, 1979). The precise mechanism is unclear but there is experimental evidence for increases in CSF levels of opiates in patients who have been treated with low-frequency TENS (Hans et al. 1991). (4) Indications: (a) Pain, although now patient *can tolerate muscle contractions.* (b) *Chronic pain syndromes* (c) *Trigger points.* (d) *Muscle guarding.*

Burst mode TENS:

(1) A series of *high frequency pulses delivered in low frequency trains.* *Another way to achieve low-frequency TENS.* (a) Pulse duration - *100-300 microseconds.* (b) Pulse rate - *Low: 2-10pps (generally 10).* (c) Intensity - *Strong, non-painful, visible muscle contractions.* (d) Treatment time - *30 min.* (e) Electrode placement - *Bracket pain site or acupressure or dermatomal regions.*

*The five characteristics of an electrical pulse*

(1) Amplitude/intensity (2) Width/duration (3)Interpulse/interbeat/interburst interval (4) Pulse vs. phase (5) Pulse rate/frequency (6) Phase/pulse charge

Electrode types:

(1) Carbon rubber - Can use *gel, WET sponge, or WET 4x4.* Dry sponge/pad will greatly decrease conductivity of the electrode (and effectiveness of rx!). (2) Self adhesive - Good for long term patients returning often for rx. May dry out. (3) Ensure good and *equal electrode contact at ALL surfaces* of ALL electrodes. Sandbags often used in clinics and may occasionally be used for good

Iontophoresis Application(not a highlight)

(1) Current type/waveform - DC. (2) Current amplitude - 4.0 mA. (3) Treatment duration - 10-40 min. (4) Total current dosage - 40-80 mAmin.

How many types of traction are there (know differences)

(1) Manual traction. (2) Positional traction (3) Mechanical traction (4) Mechanical traction static vs. intermittent (5) Auto-traction (6) Inversion devices (7) Gravity dependent traction

*Physiologic responses to electrical current*

(1) Physiological effects may be thermal, chemical or physiologic. (2) All applied electrical current increases tissue temperature. Tissues that provide more resistance will heat up more. (3) Nerve and muscle tissue have minimal thermal effects (good conductors).

duty cycle

(1) Ratio of on/off time in seconds. (2) Ratio of 1:0 (i.e., continuous current) produces rapid fatigue. Good for mm spasms. (3) Ratio of 1:1 good for mm re-education. (4) Ratio of 1:3 to 1:5 appears optimal for strengthening. (5) Ratio and absolute time may differ - 1:3 ratios could be one second on and 3 seconds off or 25 seconds on, 75 off or 100 on, 300 off, etc.

Body tissue variables:

(1) Skin resistance is very high, and so resistance must be minimized. (a) Remove oil, dirt, and superficial epithelial cells by washing or abrading skin (remember, I=V/R, and our intent is to maximize I and minimize V). (b) Ensure good conductance between electrode and skin (tap water or electrode gel). (c) *Increase in body fat* or large region may require an *increase in amplitude* to get good contraction. (d) If possible warm body part prior to treatment to enhance conductivity. (2) Underlying tissue. (a) Cannot change (unless you do liposuction, or skin the patient, or something ludicrous like that), but need to be aware of how the underlying tissue properties can affect the accomplishment of our goal. (b) Conductivity directly proportional to water/ion content. (c) Impedance inversely proportional to water/ion content. (d)* Good conductors--nerve, muscle (muscle about 75% water).* (e) *Poor conductors--fat (about 15%), skin (about 16%), and bone (about 5% water).*

Conventional TENS

(1) This is also known as *sensory-level stimulation or high rate TENS*, and can be used for any painful condition, most commonly in the *acute stage of tissue healing.* (2) The sensory stimulation is comfortable, providing excitation of large afferent nerves. (3) Pain reduction is attributed to the Gate control theory (activation of large diameter, fast-conducting sensory fibers inhibit the transmission of painful stimuli by small diameter, nociceptive fibers). (4) Indications: (a) Best for *acute pain*, but may be used for any painful condition, especially when *muscle contraction increases pain* or is contraindicated. (b) *Post-operative* pain management. (c) May be used in conjunction with ice, compression and elevation

Manual traction.

(a) *Therapist* applied traction force. (b) Allows physical therapist and the patient to "feel" for the patient's response. (c) Uses: (i) Assessing the effects of traction on C-spine or L-spine. (ii) Acute phase application. (iii)Treating SI or cervical dysfunctions.

*Direct current*

(a) Also called "galvanic", is the uninterrupted flow of charged particles in 1 direction. (b) There is a net transfer of ions away from one pole to the other pole. (c) Ion shift CAN lead to tissue burns! *Clinical Applications: consist of iontophoresis, wound healing, and stimulation of denervated muscle.*

Reduces disc protrusion by:

(a) Decreased central disk pressure. (b) Vacuum effect. (c) Increased PLL tension.

Treatment parameters traction

(a) Force. (b) Position. (c) Mode. (d) Duration and frequency. NOTE: Adapt the traction to the patient, not the patient to the traction!

*Electrical stimulation generated muscle contraction (extrinsic).*

(a) Muscle is excited by a *motor nerve impulse* with innervated muscle tissue, since nerve tissue has a lower level of excitation (threshold) than muscle. (b) The *large nerve fibers and motor units are activated first* (located superficial to the smaller nerve fibers on the periphery of the nerve). (c) Visually similar to the muscle response created by normal physiologic activity, but is metabolically expensive and *fatiguing*, due to the *synchronous* firing of motor units. (d) Denervated muscle tissue is stimulated directly.

*Voluntary muscle contraction (intrinsic).*

(a) Muscle is stimulated by a *motor nerve impulse.* (b) Body normally activates *small nerve fibers and smaller motor units initially*, bringing in the larger fibers and their motor units when needed. (i) The recruitment of motor units is *asynchronous which helps to slow the onset of fatigue.*

Low Rate TENS Application

(a) Pulse duration - *100-200 microseconds* (can range from 100-600). (b) Pulse rate - *Low <20pps*. (typically 2-10pps) (c) Intensity - *Strong, non-painful, visible muscle contractions or patients motor threshold. (Low Rate TENS)* (d) Treatment time -* 30 min.* (e) Electrode placement - *Bracket pain site or acupressure or dermatomal regions.* (f) Elicits a release of endogenous opiates and can provide relief lasting from *1-6 hours.* Pain relief is delayed but lasts for longer periods. (g) It is sometimes recommended that treatment be initiated with conventional TENS to obtain the rapid onset of pain relief. As the pain subsides,

Conventional TENS Application:

(a) Pulse duration - *Less than 100 microseconds.* (b) Pulse rate/freq - *100-150 pulses per second (pps).* (c) Intensity/amplitude - *Low sensory threshold (maximum tolerated tingling).* (d) Treatment time - *30 min. to 24 hrs. (theoretically)* Modulated pulse width, frequency and/or amplitude - prevents the patient from accommodating to a predictable, unchanging flow of pulses. (e) Electrode placement -* Bracket painful site or use on acupressure or dermatomal regions.* (i) If pain is not reduced, then electrode placement should be adjusted. (f) Pain reduction is immediate but only lasts while the *TENS is on.*

Physiologic effects of traction(Respiration response)

(a) Respiration response: (i) Decreased inspiratory vital capacity and tidal volume with traction garment. (ii) *Increased respiratory rate - 1-2 beats per minute.* (b) Precautions: (i) Patients with respiratory disease(s) are less likely to relax during treatment - The treatment becomes less effective. (ii) Use traction with caution for patients with mild to moderate respiratory disease symptoms. Severe respiratory disease patients are poor candidates.

*Type of nervous tissue affected by electricity*

(a) Sensory (afferent). (b) Motor (efferent). (c) Autonomic (viscera, involuntary muscle).

*Alternating current*

(a) The continuous directional flow of charged particles. It has an equal ion flow in each direction, and thus no charge remains with the tissue. (b) Premodulated current is an alternating current with a medium frequency and subsequently increasing and decreasing current amplitude, produced by a single circuit and only 2 electrodes. * Clinical Applications-pain relief.*

*Cervical traction parameters force*

(a) The head weighs approximately 10-15 lbs. (b) Cervical traction starts with 10-15 lbs. (c) Increase weight by 2 lbs per treatment if no adverse reactions are noted. (d) DO NOT exceed 40 lbs!

Auto-traction

(a) The traction force is applied by *patient pulling* with their arms. (b) Split table for tilting and/or rotating. (c) Patient positioned in maximal comfort and gradually moved into former painful positions during rest cycles. *Shortfalls:* *Difficult to maintain traction force.* *Increases intradiscal pressures.*

Inversion devices

(a) Traction force applied by the patient's body weight hanging inverted. (b) *50% BW in full inversion.* (c) Multiple types can be found in the market. (d) By varying the angles it will improve the patient "intolerance" issues. *Shortfalls:* *Multiple side effects reported-BP,Cardio* *Often performed without medical clearance and/or supervision.*

Gravity dependent traction

(a) Traction is applied by upright body suspension. (b) Has a higher patient tolerance. (c)* 40% BW in full suspension.* (d) *Ability to integrate manipulation, positioning, exercise, and modalities* (e) *Vest/corset may restrict respiration.*

Mechanical traction:

(a) Uses *computerized* motor traction force. (b) It has an automatic tension adjustment. (c) May be set at sustained or intermittent tension. (d) 96.6% traction force is needed for efficiency. (e) Ability to position the patient in various positions

Positional traction.

(a) Using *patient positioning* or movements to provide a longitudinal pull or distraction force. (b) Examples: (i) *Knees to chest *positioning opens bilateral intervertebral foramen. (ii) *Side-lying over a pillow* or foam roll - Maximally opens unilateral intervertebral foramen. (aa) Good for *scoliosis* patient's and *HNP patient's with lateral shift.*

Monophasic

(aa) Waveform made up of pulses composed of a pair, exponentially decaying phases, both in the same direction. (bb) May be used for any clinical application-commonly used for *tissue healing and acute edema.*

Physiologic effects of traction(Cardiovascular responses:)

(c) Cardiovascular responses: (i) Increased systolic and diastolic blood pressures with inversion traction. (ii) Decreased heart rates occur during inversion traction. (d) Precautions: (i) *Use caution when using inversion traction techniques in clinic or at home, especially for those with hypertension or at risk for cardiovascular disease.*

Mechanical traction static

(i) Applied for few minutes or up to ½ hour. (ii) *Favored for patients with HNP. * (iii)Generally requires: (aa) Shorter treatment times. (bb) Lower force levels.

Mechanical traction intermittent.

(i) Applied to the patient for up to ½ hour with varying traction/rest times. (ii) *Favored for joint motion - joint dysfunction. * (iii)Length of traction phase determines separation. (iv)Generally uses: (aa) Longer treatment times! (bb) Higher force levels!

*Major uses of electrical stimulation*

(i) Muscle contraction. (ii) Pain modulation (sensory nerve stimulation).

Lumbar Traction Spine (over-all biomechanical effect(s)):

(i) Vertebral Distraction (joint distraction) - For distraction to occur, the force applied must be great enough to cause sufficient elongation of the soft tissues surrounding the joint to allow the joint surfaces to separate. (aa) Traction results in overall spinal motion through segmental distraction between adjacent vertebrae. (bb) *The amount of movement varies with the patient position, amount of force, and length of time applied.* (cc) *Separation of 1-3 mm per intervertebral space may be accomplished with traction.*

Parameters for positioning the patient during cervical traction.

*Between 20-30 degrees of cervical flexion.* *DO NOT lower treatment table with patient's head in cervical traction unit!*

*Sequence of response with increasing amplitude.*

*Sub-sensory* *Sensory threshold.* *Motor threshold.* *Maximum motor without pain.* *Pain threshold* Pain tolerance.

*Pulse vs. phase*

*The entire wave form is the pulse. The pulse is made up of 1 or more phases.* phase+ phase =pulse(entire wave form)

Traction Duration and Frequency

-At least 3-4 minutes needed for relaxation of erector spinae muscles -10-30 minute duration -3-5x per week

Lumbar traction parameters force

-Start with 1/3 to 1/2 of the patient's body weight. -Increase the weight by 5 lbs per treatment if no adverse reactions are noted. -Max weight 75% of body weight.

Lumbar traction parameters used during patient positioning

-Supine : Hips flexed from 45 to 90 degrees with a pillow or stool placed under the knees. -Used to facilitate spinal flexion for DJD, DDD, hypomobility.

Indications for spinal traction (joint dysfunction):

1) Restore normal joint function by. (a) Stretching a tight capsule. (b) Mobilizing hypo-mobile segments. (c) Freeing entrapped synovium. (d) Relieving muscle spasm.

Electrotherapeutic devices (E-stim) generate ____ different types of current that, when delivered into human tissue, will produce specific physiologic changes.

3

Generally considered ____ BW for lumbar traction

50% BW

*Clinical biofeedback definition*

A technique using sensitive monitoring instruments that provide EXTERNAL feedback to monitor INTERNAL physiological activity.

*Pulsatile current*

An interrupted flow of charged particles where the current flows in a series of pulses separated by periods when no current flows. *1)Monophasic 2)Biphasic 3)Polyphasic*

Traction

Application of a mechanical force to the body in a way that separates, or attempts to separate, the joint surfaces and elongate the surrounding soft tissues

Pulse width/duration

At a pulse rate of *20-40pps,tetanic* contraction occurs.Tetancy is a steady muscle contraction vs a twitch

Bipolar setup

Both electrodes are over target tissue. Use for larger more diffuse area. Electrodes are the SAME SIZE to have = current flow at both sites.

*A-delta fibers*

Carry pain. *Smaller* than A-beta fibers, mediate the sensation of cold and the first components of the sensation of *pain*. Mylenated; *short duration pain*, sharp pricking sensation. Conduction velocity = 6-36 m/sec.

C fibers

Carry pain. The slowest and smallest, mediate the sensation of warmth and the main component of the sensation of pain. In addition, C fibers sub serve most of the autonomic peripheral functions. Unmylenated, *long duration pain*; dull/diffuse pain. Conduction velocity = <1 m/sec.

Polyphasic

Waveform common in *Russian* and Interferential currents. The waveforms are generally symmetrical. (dd) Russian - Waveform with specific parameters intended for quadriceps muscle strengthening. The protocol was developed in the training of Russian Olympic athletes. (ee) Clinical application is strengthening.

Electrode placement variables: Spacing far apart

Far apart produces deeper current flow. *For deepest penetration of electrical current place pads on either side of a joint.* *Allow at least ½ to 1 electrodes' worth of space between each electrode you place on the patient.*

*Amplitude/intensity*

The distance from isoelectric line to *peak* of wave. Measured on both sides of the isoelectric line if wave form is biphasic. Amplitude is the *magnitude* of the current.

Rate of rise (ramp or surge) - Only needed if have on/off time.

Gradually increasing amplitude of current (ramp-up) or gradual decline (ramp-down).

Biphasic

May be symmetrical or asymmetrical, and if asymmetrical, may be balanced or unbalanced. There is no clinical difference between asymmetrical and symmetrical, it has been suggested that asymmetrical are more comfortable on smaller muscles and symmetrical are more comfortable on larger muscles. (bb) Biphasic and Alternating currents look alike but are not the same. (cc) Clinical applications are *strengthening, pain relief, and chronic swelling.*

Gate Theory (Melzack and Wall, 1965).

Modulation of pain by TENS. (a) Painful stimuli are received at the spinal cord via C and A-delta nociceptor afferents. Secondary or projection neurons transmit this painful stimulus to the brain. (b) When stimulated, non-nociceptor sensory afferents (i.e., A beta fibers) excite inhibitory interneurons in the spinal cord. Increased non-nociceptive inputs (arriving at the spinal cord much faster than the pain fibers) cause presynaptic inhibition of the projection neurons. This sensory overload effectively closes the spinal gate to the cerebral cortex and decreases the sensation of pain. (c) Treatment modalities that stimulate A-beta fibers - E-stim, manual therapy, massage and touch!

Biofeedback purpose

Muscle re-education - Goal is to achieve high electrical output.

Should traction be used as standalone tx

No,it should *accompany* overall tx

Monopolar setup

One of the required electrodes is over the target tissue, the second required electrode is over non-target tissue. Used to focus treatment at small, localized area. Use large dispersive pad with relatively smaller treatment pad.

A-beta fibers

The largest fibers, mediate the sensations of touch and mild pressure, as well as the sensation of position of joints and vibration. Conduction velocity = 36-72 m/sec.

*Width/duration*

The length of time *1 pulse* lasts, represented by time from *deflection* of baseline to return to baseline. Measured in milliseconds or microseconds.

* Pulse rate/frequency*

The number of pulses per second. (a) In general most stimulating units are low frequency at *1-200 pps.*

*Phase/pulse charge*

Quantity of electricity delivered to tissue in each phase or pulse. Measured in microcoulombs. Represented by area under curve. Amplitude and duration of the pulse determine the amount of charge. The charge is responsible for the thermal, chemical and/or physiologic response by the body to e-stim.

T/F: Iontophoresis uses direct current (DC) to drive medication through the skin and into the underlying tissues.

TRUE

T/F:Increased disc volume *(hysteresis)* and increased disk pressure may contribute to immediate increase in pain following traction.

TRUE

T/F: Biofeedbakc is a TOOL

TRUE: Biofeedbakc is a TOOL!

*Interpulse/interbeat/interburst interval*

The time *between* pulses, beats, or bursts, when *no current flows.* Measured in milliseconds. It is not rest time.

which traction: 40% BW manipulation, positioning, exercise, and modalities

gravity dependent traction

which traction: 50% BW

inversion devices

Dexamethasone sodium phosphate (DSP)

is the most commonly used steroid.* 0.4%* strength is commonly used. DSP has a *(-) polarity* and must be placed under the *cathode* to drive it into the underlying target tissue.