Modalities Week 9-11 Flashcards

4 Reasons Electrical Currents is Used in Rehab

1. producing muscle contractions (strengthening, re-education)
2. prevents atrophy, DVT formation, pressure ulcers
3. controlling pain
4. promoting tissue healing, decreasing edema

What is Direct Current?

- continuous undirectional flow of charged particles

- Used for intophoresis

- stims contractions in denervated muscles

What is Alternating Current?

- continuous bidirectional flow of charged particles
- used for pain control and muscle contraction

Pulsed Current

- interrupted flow of charged particles
- used for pain control, tissue healing and muscle contraction

3 Time-dependent parameters

1. Pulse duration - 1 complete wave
2. phase duration - half of a pulse
3. interpulse duration - amt of time between pulses

What are the EC parameters

Amplitude - magnitude of current or voltage
Frequency - # of cycles/pulses/seconds (Hz or pps)
On-time - train of pulses
Off-time - tome between train of pulses
Ramp up - time it takes for current to reach max amp from 0
Ramp down - time it takes for current amp to decrease from 0

Effect of EC

Nerve Depolarization
- nerves polarized at rest
- + charge outside, - charge inside
- ions move (Na, K), electrical charge in and out of cell

Action Potential
- Current with enough amp and duration causes AP move along nerve
- AP moves in waves; nerve needs time to rest
- all or nothing effect

AP in Adjacent Areas
- Natural stim (1 direction)
- External stim (both directions; only effect natural direction)
- speed is determined by diameter (myelination)

Sensory and Motor nerves
- sensory nerves respond to shorter amp and pulse duration (80 microsec)
- motor nerves respond to longer amp and pulse (150-350 microsec)

Direct Muscle Depolarization
- electricity delivered directly to nm, not its nerve
- charge can repel drug molecules
- can help healing, reduce edema acut inflam

4 Contrindication of EC

1. cardiac pacemaker/ unstable arrhythmias
2. placement over carotid sinus
3. areas of venous/arterial thrombosis or thrombophlebitis
4. pregnancy

4 Precautions of EC

- cardiac disease
- impaired sensation and mentation
- malignant tumours
- open wounds

3 Adverse Effects of EC

1. burns
2. inflammation
3. pain

Documentation of EC

- area treated
- position of pt.
- stim para
- electro placement
- duration
- response to intervention

2 Pain Control Theories

1. gate control
2. endogenous Opiods

What is gate control?

- pain modulation at spinal cord
- Melzack and Wall discovered theory in 1965
- non-painful input closes nerve gates to painful input preventing the pain sensation to travel

What is Endogenous Opioids:

- getting a high from chemicals in the body
- body producing natural substances to help block the pain

Conventional (high-rate) TENS

Setting:
short duration pulse
high frequency
low amplitude
Sensation:
Comfortable sensation w/o contraction
Pain Relief:
gait control theory
Treatment Length:
effective only while stim applied
continuous
Typical Conditions:
acute injury
repetitive strain

Acupuncture-like (low rate) TENS

Settings:
long duration pulse, low frequency, high amp
Sensation:
Twitching
Pain Relief:
Stims endogenous opioid prod and release
Treatment Length:
Effective for 4-5hrs after stims ends
no more than 45 mins/session
Typical Conditions
Chronic conditions

IFC (interferential Current)

- more comfortable stim bc of low amp currents
- more total current to stim larger area
- less burn risk

4 enhances for Tissue using Electrical stim

1. tissue healing
2. controls inflammation
3. decreases edema
4. Iontophoresis

EC for muscle contractions

Inntervated muscles = NMES
Deneravated muscles = EMS

4 EMS benefits

1. strengthens muscles
2. improves muscle endurance
3. improves cardio health
4. decrease muscle atrophy

3 Signs of Muscle Fatigue

1. uncomfortable sensation
2. tremulousness
3. inability to complete ROM

Precautions of EC

- may cause DOMS

Contraindications of EC

delay or disrupt healing

How ES Strengthens Muscles

Overload Principle
increases pulse duration, amp, electrode, size, external resist
higher load => higher force => strengthening
Specificity
contractions strengthen fibres
more effect on type 2 fibres than type 1

Clinical Applications

Orthopedic
increases strength after surgery (ACL, TKA)
non-surgical management (OA, RA)
Neurological
stims intact peripheral nerves with CNS dmg
Spinal Cord Injury
improves circulation
contract muscles to assist locomotion, hand grasp
Stroke
improved gait
increase ankle DF torque
Reduce agonist-antagonist co-contraction

Contraction in Denervated Muscles using EMS

becomes denervated due to disease or nerve injury
requires pulse duration >10ms
improvements don't persist after stim is done

Muscle Motor points

Duchenne mapped the point of the spine
spots where nerves are stimed
wheres least intensity / current needed

4 Effects of Traction

1. jt distraction and mobilization
2. reduction of spinal disc protrusion
3. soft tissue stretching
4. muscle relaxation

What happens in Jt distraction?

- separation of 2 articular surfaces
- reduces jt compression and widen intervertebral foramines
- reduces pressure on articular surfaces, intraarticular structures, nerve roots

Reduction of Disc Protrusion

amt of separation of vertebrae
can be done with Pt's 25% of body
50% of body weight for lumber spine
7% of body weight for cervical spine
lumber = 60-120lbs
cervical = 15-30lbs

Clinical indication of traction

herniation
nerve root impingement
jt hypermobility
subacute jt inflammation

Contraindications of Traction

-acute injury or inflam
-jt hypermobility
-peripheralization of symptoms w/ traction
-uncontrolled hypertension

Precautions of traction

-medial disc protrusion
-displaced annular fragment
-severe pain
-inability to be supine or prone

Adverse Effects of traction

excessive force may increase symptoms
rebound increase pain
lumbar radicular discomfort

static traction

muscle relaxation due to depression of monosynaptic response

parameters:
hrs or days
light weight
only immobilization

Sustained traction

-mins to half hour
-larger weights

intermittent traction

small changes in mm
tension to produce relaxation stiming GTO to inhibit alpha motor neuron firing
rhythmic

3 Types of traction Apparatus

1. Mechanical
- belts and halters
- positions
- devices
- traction table, over the door
2. Manual
- application by therapist
3. Self and positional
- body weight to exert force
- used for lumbar

Advantages of Traction

inexpensive
does not need full supervision
force and time readily controlled, graded and re-applicable

Disadvantages of Traction

- time-consuming setup
- lack of pt control

Effects of Compression

improves venous and lymphatic circulation
- increases external hydrostatic pressure
- intermittent compression may be better than static
limits shape and size of tissue
increases tissue temp

3 ways Compression reduces edema

1. increases extravascular hydrostatic pressure
2. promotes circulation
3. may move fluid proximally

compression v.s VSU (venous static ulcer)

- improves circulation
- improves healing rate of VSU
- multilayered compression is more effective

DVT prevention with compression

- increase compression = increase circulation = decrease DVT
- compression used w/ blood thinners to circulate blood

residual limb shaping

intermittent compression can reduce residual limb

precautions

impaired sensation and mentation
uncontrolled hypertension
cancer
stroke

contraindication of compression

heart failure/pulmonary edema
recent/acute DVT, thrombophlebitis
acute local skin infection