What are electrotherapies and how do they work?
Electrotherapies and Electro Physical Agents (EPAs) are names used to describe different electrical therapeutic modalities that a physiotherapist might use to aid a patient’s recovery. Some electrotherapies use electric currents passed through the body to stimulate nerve fibres and stimulate muscle contractions e.g. Transcutaneous electrical nerve stimulation (TENS) and neuromuscular electrical stimulation (NMES). Other forms of electrotherapies involve the use of electrophysical and biophysical energies to cause different tissue responses e.g. Laser, shockwave, and pulsed electromagnetic field therapy (PEMF).
In this blog, we’ll delve a little deeper into some of the most popular ones used in veterinary physiotherapy.
Transcutaneous electrical nerve stimulation (TENS) and Neuromuscular electrical stimulation (NMES)
How do TENS and NMES work?
Both TENS and NMES work by applying electrical stimulation to the patient through electrodes and ultrasound gel placed on the skin. TENS is predominantly used to assist with pain relief, while NMES is used to cause muscle contractions.
What can they be used for?
TENS is used to assist with acute or chronic pain management. The effects of NMES includes muscle contraction and altered blood flow with short term treatment but with long term treatment you can achieve strengthening (most effective when combined with active exercise) and therefore a slower rate of muscle loss in very weak patients.
When is it not a good idea to use TENS or NMES?
The use of both TENS and NMES should be avoided in patients that react adversely to treatment, the electrodes, or ultrasound gel, those with pace makers or skin issues, or direct application over the eyes.
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Light amplification by stimulated emission of radiation
How does laser work?
Laser uses very focused beams of light that are generally red and/or near infrared. These light waves are of a specific length and power to be able to reduce inflammation and pain, and increase tissue healing time when applied to a patient. Most therapeutic lasers are classified as class 3b or class 4, this classification is based on the power of the laser and the supposed risk of eye damage (this risk is minimal to non-existent when wearing proper eye protection), with class 4’s being the most powerful. The beams themselves are “non-ionising” so will not harm healthy tissue.
What can it be used for?
Laser can be used for a multitude of different conditions including acute and chronic pain management, post-operative rehabilitation and conservative management, superficial and deep wounds, skin conditions, osteoarthritis, nerve damage, and many others that are being researched all the time.
When is it not a good idea to use laser?
Laser should not be applied directly through the pupil of the eye which is why we must wear goggles during the application. However, care should also be taken not to apply laser directly over recent locally injected medication, cancer, or over the uterus of a pregnant patient.
Pulsed electromagnetic field therapy (PEMF)
How does PEMF work?
PEMF uses electromagnets to cause changes in the body’s tissues to aid in healing. Pulsating magnetic fields induce small electric currents in the target tissues, thought to re-establish nutrient flows into and out of the cells that have been lowered due to damage, in order to repair and regain normal function.
What can it be used for?
PEMF can be used for acute or chronic pain management, including osteoarthritis. It can also be used to treat swelling and bruising caused by injury and may be beneficial in bone and wound healing. Another common use is in sports therapy for tight muscles, as PEMF can be used to increase blood flow to an area to aid in healing and hopefully relax tense muscles.
When is it not a good idea to use PEMF?
There are certain situations where the use of PEMF should be avoided in favour of a different therapy. These conditions include:
If anyone present has an implanted cardiac pacemaker, whether this is the patient, the owner, or the therapist.
If anyone present is aware that they have a cancerous tumour.
If anyone present is in the early stages of pregnancy.
So hopefully this gives a little insight into what electrotherapies are and why they’re used so often in veterinary rehabilitation!
Have a great week,