We’ve come to the conclusion that TENS is a viable and, some may say, even preferential treatment for pain relief. But of the myriad of devices of varying cost out there why should you choose PainPro? What’s so special about the PainPro that makes it the unit of choice for people considering TENS? To understand this, I’m so happy to say that we have to go into a little bit of Physics .
Historically, TENS had a reputation of being something that worked for a while then lose its effectiveness on the individual. To understand the reason for this it is important to understand the waveform of the applied current.
Waveform is the description that is used to illustrate what the electric current leaving the unit looks like:
The old style TENS machines used square waves as a basic repeated pattern. Whilst they provided pain relief their onset of action was very abrupt making the experience somewhat uncomfortable due to the fall time being virtually zero ie from resting to full intensity is virtually an instant process as is the return journey. This would cause sudden jerky movements that would not be conducive to normal behavior or relaxation during treatment.
As there is a basic repetition of the applied square wave after a while its effectiveness decreases. This is termed ‘accommodation’ and is a natural phenomenon within the body in response to constant and predictable stimuli, ticking clock, dripping tap, etc.
The modern machines have a sinusoidal wave that gradually reaches the maximum selective intensity before returning back to zero/starting position or resting phase. Whilst this is much gentler than the square waves, again the body can accommodate for these rendering them less effective over time.
Factors to consider when selecting a TENS machine
There are typically four TENS modes used in clinical practice:
Most common – High frequency/Low intensity TENS
Skin deep travel of waves → stimulation of afferent nerves → disruption of ascending pain pathways
Analgesic effect is of rapid onset but relatively short duration duration of action – typically lasting only a few hours post treatment.
Acupuncture – like TENS
Low frequency/High intensity/Long duration
Initiates and maintains a muscle contraction (effect is on the muscles so waves travel deeper and act to stimulate muscle afferent nerves: pain relief is primarily through the release of endogenous opioids via descending pain pathways)
Analgesic effect – slower onset of action but lasts longer than with Conventional TENS
Burst Train or Wave TENS
(Blended Sensory & Motor Level Stimulation)
A mixture of conventional & Acupuncture like TENS
Comprises the application of ‘Pulse Trains’ or bursts of pulses
The frequency of the trains is 1-4Hz and the internal frequency of the Trains is around 100HZ. Is often preferred due to a more comfortable patient experience.
Analgesic effect is generally maintained for several hours post application/treatment
(Sometimes referred to as Noxious level stimulation)
Generally viewed as last resort or for painful procedures eg, skin debridement, suture removal etc.
Application is at high frequency (100-150Hz), long pulse duration and at highest tolerable intensity for short periods of time (≤15mins)
Modulated output is preferred:
This means the output varies as a mixture of two or more of the different TENS modes in a cyclic fashion to overcome ‘accommodation’ and provide more comfort to the patient.
The PainPro has a sophisticated modulated output of TENS and the whole unit not only concentrates on TENS and pain relief but, unlike other units it may be compared with, also has micro current technology delivered as a continually varied current to tap into and augment the body’s own healing capacity.
Thus the total treatment option or output of the PainPro is described as ‘Bioelectric Microcurrent Wave Technology’ to distinguish it from other units that don’t come close to the mark when it comes to offering the full range of treatments.
Bioelectric theory of Pain
Each tissue type in the body has its own signature electrical frequency. What happens when this signature frequency, or resting potential as is more commonly termed in the scientific community, is disrupted? And how does this manifest as pain and slow down the healing/recovery process?
To understand this we need to touch upon a little biochemistry!!!
All our cells are surrounded by a membrane (a lipid bi-layer) with proteins embedded in it. The membrane acts as an insulator and a diffusion barrier to the movement of ions.
Virtually all eukaryotic cells maintain a non zero trans-membrane potential by selectively regulating ions via ion pumps, e.g, Na+ K+ pump, the levels of specific ions both inside and outside of the cell. This creates a trans-membrane potential typically in the region of -40mV to -80mV (cell interior to exterior)
Why is this important? You may ask
The membrane potential has two basic functions –
- It allows the cell to function as a battery providing power to operate a variety of molecular devices embedded in the membrane
- Important in electrically excitable cells e.g, neurons and muscle cells for transmitting signals.
Under normal conditions the trans-membrane potential or resting potential is held at a relatively stable value which allows all the cell processes to function harmoniously.
Whenever there is tissue trauma or dysfunction:
- There is a decrease in ATP and disruption of the sodium pump. (for those of you not familiar with ATP and its function we will come on to that in a short while)
- The cells increase their electrical resistance and the injured area will have a higher electrical resistance than the surrounding tissue
- This decreases electrical conductance throughout the injured area and decreases electrical capacitance which leads to impairment of function and inflammation
- The cells become less able to receive nutritional input, water, minerals etc, and are unable to remove toxins.
All of these events are perceived by the individual as pain.
THIS IS NOT AN ENVIRONMENT THAT SUPPORTS HEALING!
Due to the damage, the loss of intracellular ions and the disruption of the sodium pump mechanism the damaged cells produce an electric current which is termed the ‘current of injury’ – almost like an SOS
WHAT CAN WE DO TO HELP?
We have TENS plus EMS in the PainPro to relieve pain centrally and locally
WHAT MORE CAN WE OFFER?
We now have in our new generation of PainPro microcurrent technology that mimics and augments the endogenous current flow allowing cells in the traumatized area to regain their capacitance.
- REGAIN CAPACITANCE → REDUCE
- RESISTANCE → IMPROVED BIO ELECTRIC
- FLOW → REESTABLISH HOMEOSTASIS → HEALING
ATP is replenished allowing membrane active transport to resume → Inflow of Nutrients & Outflow of toxins + waste (we’ll get to the role of ATP next)
Pre- clinical studies have shown that externally applied stimulation can:
- Cause migration of epithelial cells and fibroblasts in to the wound site
- Increase ATP concentrations in tissues
- Increase protein and DNA synthesis
- Promote healing of soft tissues or ulcers
- Accelerate the healing of damaged neural tissue
- Reduce oedema
- Inhibit growth of various pathogens
Electric therapy is nothing new with the ancient Egyptians, Greeks and Romans using electric eels for headaches and neuralgia.
How does microcurrent treatment differ from TENS/EMS treatment?
The main treatment of TENS/EMS therapy is pain relief with concomitant small scale repair of tissues due to intermittent delivery of appropriate current frequency → direct pain relief.
Mircocurrent therapy is specially designed to tap in to the body’s own (SOS) frequency to normalize the environment, promote healing and hence remove the source of the pain → indirect pain relief/removal.
WHAT CAN YOU EXPECT IN A MICROCURRENT TREATMENT?
During treatment, electrodes are placed at strategic locations to direct currents to target tissues. Treatment microcurrents are very weak and typically sub sensory so do not stimulate sensory nerves hence the subject normally does not feel anything.
Microcurrent therapy has been used and recommended for:
Slow healing wounds
Sports injuries- ACL, MCL, breaks, fractures etc.
Tendon and ligament pain