neuromuscular electrical stimulation NMES Flashcards
what is NMES?
-form of electrical stimulation at sufficiently high intensities to produce muscular contraction
what are slow twitch fibres?
-red, highly vascular
-small diameter motor neurones
-low conduction velocity
-freq rate 20-30Hz
-many oxidative enzymes
-fatigues slowly
what are type 2 / fast twitch fibres?
-white, less vascular
-higher conduction velocities
-large force for short periods
what are the long term effects of NMES?
-neural plasticity - neural activation
-muscle plasticity - change in fibre type in response to freq of stimulation
what sensory fibres are activated with NMES?
-a delta fibres - pain
C fibres- pain
-a beta - sensory - not pain
what are the uses of NMES?
-to preserve muscle mass and function during disuse and immobilisation
-to recover muscle mass and function
-to improve healthy muscle function
in what conditions can NMES be used for?
-can be useful for critically ill pts in ICU
- post injury. surgery eg ACL
-following removal of cast post fracture
-pelvic floor muscle weakness / urinary incontinence
-peripheral nerve injury
-neurological conditions eg subluxation of shoulder w/ stroke
how can NMES help in neurological conditions?
-improve motor function
-increasing muscle strength
-reducing spasticity
-can help to reduce shoulder subluxation in stroke
what does denervated muscle lead to?
-atrophy
-fibrosis
-degeneration and fibrosis of the motor nerves
-increase fatty tissue
-thickening of arterial walls
what is the purpose of electrical stimulation of denervated muscle?
-to prevent or slow atrophy while waiting for re-innervation
-higher intensities and longer pulse durations needed
what type of NMES current is used most often?
-symmetrical biphasic pulsed current
what muscle fibres are stimulated at low freq (less than 30Hz)?
- slow twitch fibres
what muscle fibres are stimulated at high frequencies? (greater than 50hz)
-fast twitch fibres
why is request interval required with NMES?
-rest is required to replenish ATP and CP
what are the limitations of NMES?
Discomfort - may not be tolerated by all patients
fatigue - can be limited by - reducing pulse duration, start w/ short treatment times
