NMES - Part 2

Question 1

NMES parameters for muscle strength: Pulse Frequency?

Answer 1

35-80 pps

Question 2

NMES parameters for muscle strength: Pulse duration for small and large muscles?

Answer 2

150-200 microsec for small muscles, 200-350 microsec for large muscles

Question 3

NMES parameters for muscle strength: Amplitude for injured and uninjured?

Answer 3

> 10% MVIC for injured; > 50% in uninjured

Question 4

NMES parameters for muscle strength: On:Off times?

Answer 4

6-10 seconds on; 50-120 off with a ratio of 1:5initially (may reduce over treatments)

Question 5

NMES parameters for muscle strength: Ramp time?

Answer 5

at least 2 seconds

Question 6

NMES parameters for muscle strength: Treatment time…how long to produce how many repetitions?

Answer 6

10-20 minutes to produce 10-20 repetitions

Question 7

NMES parameters for muscle strength: Times per day?

Answer 7

every 2-3 hours while awake

Question 8

What 2 types of current can you use for Electrical Muscle Stimulation? (EMS)

Answer 8

1) Interrupted DC

2) Low frequency sinusoidal AC (usually uncomfortable)

Question 9

What is Electrical Muscle Stimulation (EMS) used for?

Answer 9

maintain muscle in a healthy state while the injured axon regenerates (controversial)

Question 10

When the muscle is denervated, what three changes are there in the muscle?

Answer 10

1) Denervation atrophy
- decrease in muscle weight and bulk, decrease in muscle fibers, contractile protein, and sarcoplasm fatty infiltration
2) Partial depolarization of the sarcolemma
3) Change in acetlycholine sensitivity and dispersion of receptors

Question 11

EMS DC Current Specs: Amplitude?

Answer 11

Max contraction w/ least discomfort

Question 12

EMS DC Current Specs: Electrode technique? - monopolar, dipolar, or quadrapolar? Which electrode is active?

Answer 12

monopolar technique with cathode as active electrode (black lead) - is usually done with a special electrode called a pencil electrode to interrupt the current flow (some authors suggest use of bipolar technique with sinusoidal AC)

Question 13

EMS DC Current Specs: Where is the stimulation site for denervated muscles?

Answer 13

need to search along the entire muscle since the motor point is no longer active

Question 14

EMS DC Current Specs: Expected outcome of muscle contraction?

Answer 14

contraction may appear wormlike or sluggish ( 10-20 contractions per muscle)

Question 15

EMS DC Current Specs: How often should the treatment be performed?

Answer 15

up to 1-2 sessions daily so patients may get specialized home units

Question 16

What two types of electrical treatments can innervated muscle be stimulated by?

Answer 16

1) Pulsed biphasic current

2) Medium frequency current

Question 17

Denervated muscle can be stimulated by which type of current?

Answer 17

DC

Question 18

What does Direct Current primarily stimulate?

Answer 18

Sarcolemma