Neuromuscular Electrical Stimulation | Transcutaneous Electrical Nerve Stimulation
In memories of all immobile dogs that were not given a second chance
What is NMES & TENS?
Electrotherapy is the passing of low to medium levels of electrical current through the body for 2 main objectives: muscle building and pain management. Given its success in humans, it was then used in strength building in race horses which have the potential to bring in huge amounts of money. After which, it was introduced to companion animals. Even though electrotherapy is now commonplace in human physiotherapy and veterinary rehabilitation overseas, it is only starting to be introduced in Singapore by RA Healing Centre. At our centre, we use EMS, NMES and TENS along with other techniques like cold laser therapy, massage and hydrotherapy to improve the rate and success of rehabilitation.
Muscle building is done with NMES (Neuromuscular Electrical Stimulation), which stimulates muscle contraction and recruitment using electrical impulses via a motor nerve. NMES has received increasing attention in the last few years because of its potential to serve as a strength training tool for subjects and athletes, a rehabilitation and preventive tool for partially or totally immobilized patients, a testing tool for evaluating the neural and/or muscular function in vivo, and a post-exercise recovery tool for athletes. The use of NMES has been cited by sports scientists as a complimentary technique for sports training and published results are available.
Transuctaneous Electrical Nerve Stimulation (TENS) is actually another form of NMES except it aims to relieve pain instead of building muscles. This is done by placing the electrode over a trigger point rather than a motor point. Trigger points are tight balls of muscle fibers that due to pain could not let go of the muscle contraction completely. Thus it is a point in the muscle which hurts when it is touched. These are points we instinctively rub on when we have an ache and say “I have a knot” particularly at the neck. Because TENS is used in very low frequency to target sensory nerves so as to override pain impules, it does not generate any muscle contractions.
Darryl L. Millis, MS, DVM, DACVS, DACVSMR, CCRP
Professor of Orthopedic Surgery & Director of Surgical Service
Robin Downing, DVM, MS, DAAPM, DACVSMR, CVPP, CCRP
Diplomate of the American Academy of Pain Management, is a a founder and past-president of the International Veterinary Academy of Pain Management.
Janet B. Van Dyke, DVM
Diplomate American College of Veterinary Sports Medicine and Rehabilitation, CCRT, CEO
Ludovica Dragone, DVM, CCRP
Vice President of VEPRA, Veterinary European of Physical Therapy and Rehabilitation Association.
Andrea L. Henderson, DVM, CCRT, CCRP
Resident, Canine Sports Medicine and Rehabilitation
Steven M.Fox, MS, DVM, MBA, PhD
President Securos. Inc
ELECTROTHERAPY’S ROLE IN CANINE REHABILITATION
An application of electrical current through the skin, transcutaneous electrical nerve stimulation (TENS) is used primarily to manage pain. A small, battery-operated TENS unit delivers an electrical current to the patient through electrodes placed directly on the skin. The pulse rate, width and intensity can be adjusted according to treatment objectives. TENS works by stimulating faster sensory nerves with an electrical impulse, causing an overload of interneurons, which limits the ability of sensory nerves to transmit pain signals to the brain, creating analgesia for the patient. The effect of this modality is short-lived, however, as it generally does not last for more than an hour. In veterinary rehabilitation, TENS is used immediately post-operatively and during therapy to help a patient work through a painful treatment.
Stimulating the nerve that causes the muscles to contract, neuromuscular electrical stimulation (NMES) is used to rehabilitate muscles. This method is delivered to the patient via leads and flexible, low-resistance electrodes that conform to the skin. NMES can be used to help prevent muscle atrophy, increase local blood circulation, and maintain or increase joint mobility. It is particularly useful in patients with edema, delayed wound healing, or in those unable to perform voluntary movement.
The NMES unit features many adjustable variables, including intensity, pulse duration, current, frequency, on-off times, ramp duration and treatment duration. Ramp duration — the amount of time from the onset of the current until the full strength is delivered — is particularly important in veterinary rehabilitation. In human physical therapy, the therapist can explain to the patient how the current and contraction will feel. We don’t have this luxury with our patients; therefore, we must provide a slow, gradual onset of contraction strength to alleviate as much discomfort as possible. An NMES treatment generally lasts 15 to 20 minutes and achieves best results when used two to three times a week.
Neuromuscular Electrical Stimulation as a Method to Maximize the Beneficial Effects of Muscle Stem Cells Transplanted into Dystrophic Skeletal Muscle
Distefano G, Ferrari RJ, Weiss C, Deasy BM, Boninger ML, Fitzgerald GK, et al. (2013)
Cellular therapy is a potential approach to improve the regenerative capacity of damaged or diseased skeletal muscle. However, its clinical use has often been limited by impaired donor cell survival, proliferation and differentiation following transplantation. Additionally, functional improvements after transplantation are all-too-often negligible. Because the host microenvironment plays an important role in the fate of transplanted cells, methods to modulate the microenvironment and guide donor cell behavior are warranted. The purpose of this study was to investigate whether the use of neuromuscular electrical stimulation (NMES) for 1 or 4 weeks following muscle-derived stem cell (MDSC) transplantation into dystrophic skeletal muscle can modulate the fate of donor cells and enhance their contribution to muscle regeneration and functional improvements. Animals submitted to 4 weeks of NMES after transplantation demonstrated a 2-fold increase in the number of dystrophin+ myofibers as compared to control transplanted muscles. These findings were concomitant with an increased vascularity in the MDSC+NMES group when compared to non-stimulated counterparts. Additionally, animals subjected to NMES (with or without MDSC transplantation) presented an increased maximal specific tetanic force when compared to controls. Although cell transplantation and/or the use of NMES resulted in no changes in fatigue resistance, the combination of both MDSC transplantation and NMES resulted in a faster recovery from fatigue, when compared to non-injected and non-stimulated counterparts. We conclude that NMES is a viable method to improve MDSC engraftment, enhance dystrophic muscle strength, and, in combination with MDSC transplantation, improve recovery from fatigue. These findings suggest that NMES may be a clinically-relevant adjunct approach for cell transplantation into skeletal muscle.