NMES & EMS

Question 1

When performing NMES on a patient, what checklist should you be performing before operating the equipment?

Answer 1

1. Contraindications screening
2. Sensation check
3. Clean the skin with alcohol
4. Position and drape the patient
5. Explain the procedure and expected sensation

Question 2

There are two types of ESTIM that are used on enervated muscle. They are ___ and ___. What type of current is only used for enervated muscles?

Answer 2

NMES and Russian (medium frequency). NMES is biphasic, pulsed current. Russian is AC current.

Question 3

How does biphasic current work in producing a muscle-strengthening effect? Where on the muscle would you electrically stimulate to produce this effect most efficiently?

Answer 3

By producing a smooth, tetanic muscle contraction with the overload principle in mind. Place the electrodes over the motorpoints.

Question 4

Eventually, the goal of NMES is to re-establish the patients ability to create maximal contractions voluntarily. What should they do during NMES to build toward this?

Answer 4

Isometric contractions with NMES induced contraction.

Question 5

With respect to the on/off ratio (surge) of NMES, a ___ duration is for endurance, and a ___ duration is for strength.

Answer 5

Shorter. Longer.

Question 6

Is patient fatigue a consideration for NMES?

Answer 6

Yes, since contractions are tetanic, fatigue can pose real danger leading to injury.

Question 7

NMES is for muscle strengthening. What is the purpose of medium frequency (Russian) stimulation? How does it work?

Answer 7

It’s use for spasm management. It works by fatiguing the muscle with repetitive, intermittent contractions which are comfortable to the patient, but still strong.

Question 8

What is the major difference in the contractile properties (neuro) of an electrically stimulated muscle verses a voluntary contraction?

Answer 8

ESTIM will recruit large motor units first, where a voluntary contraction first recruits small motor units.

Question 9

EMS (Electrical Muscle Stimulation) is used on denervated muscles in peripheral nerve injuries. Though controversial, what are its parameters?

Answer 9

It uses uninterrupted DC or sinusoidal AC to keep muscle in a healthy state until nerve regenerates and should be started early. Finding the motor end plate is not relevant here.

Question 10

What types of muscle changes occur with denervation (3)?

Answer 10

1. Atrophy: decrease in muscle weight, fiber density, contractile proteins and fatty infiltration of sarcoplasm.
2. Partial depolarization of sarcolemma.
3. Change in acetylcholine sensitivity and dispersion of receptors.

Question 11

What is unique about the treatment of denervated muscle, specifically with EMS?

Answer 11

You need to treat along the entire length of the muscle fiber, because the motor end plate is no longer active.