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gunn ims leduc physio


Intramuscular Stimulation (IMS) is a total system for the diagnosis and treatment of myofascial pain syndromes (chronic pain conditions that occur in the musculoskeletal system when there is no obvious sign of injury or inflammation). IMS is grounded in Western Medical Science, and has a solid foundation in its radiculopathic model of pain, which is now supported by many experts in the field. It was developed by Dr. Chan Gunn while he was a physician at the Worker’s Compensation Board of British Columbia in the 70’s, where he investigated the large number of mysteriously stubborn cases after frustration with the ineffective modalities at his disposal. The treatment, which utilizes acupuncture needles because they are the thinnest implements available that are designed to penetrate deep within muscle tissue, specifically targets injured muscles that have contracted and become shortened from distress.

IMS relies heavily on a thorough physical examination of the patient by a competent practitioner, trained to recognize the physical signs of neuropathic pain. This physical examination is indispensable since chronic pain is often neurological as opposed to structural, and therefore, invisible to expensive X-rays, MRI Tests, Bone and CT Scans. Failure to recognize these signs will result in an inaccurate diagnosis, and thus, a poor starting point for physical therapy.

The treatment involves dry needling of affected areas of the body without injecting any substance. The needle sites can be at the epicenter of taut, tender muscle bands, or they can be near the spine where the nerve root may have become irritated and supersensitive. Penetration of a normal muscle is painless; however, a shortened, supersensitive muscle will ‘grasp’ the needle in what can be described as a cramping sensation. The result is threefold. One, a stretch receptor in the muscle is stimulated, producing a reflex relaxation (lengthening). Two, the needle also causes a small injury that draws blood to the area, initiating the natural healing process. Three, the treatment creates an electrical potential in the muscle to make the nerve function normally again. The needle used in IMS, by stimulating muscle spindles, essentially becomes a specific and unique tool for the diagnosis of Neuropathic Muscle Pain.

The goal of treatment is to release muscle shortening, which presses on and irritates the nerve. Supersensitive areas can be desensitized, and the persistent pull of shortened muscles can be released. IMS is very effective for releasing shortened muscles under contracture, thereby causing mechanical pain from muscle pull. IMS, in effect, treats the underlying neuropathic condition that causes the pain. When competently performed, IMS has a remarkable success rate, as proven by the amelioration of symptoms and signs, even for chronic back pain with root signs.

Frequently Asked Questions

What is Gunn Intramuscular Stimulation (Gunn IMS)?

Gunn IMS is a treatment using dry needles to reduce muscle pain, joint pain and other types of body pain. Dry needles are very fine solid needles similar to acupuncture needles that do not inject a substance. The dry needles are inserted into muscles that are not functioning properly. The most important part of Gunn IMS is that it looks for problems in the nervous system that may be the root cause of the pain. This approach differs from "trigger-point dry needling", which does not look for an underlying cause of the pain in the nervous system, and only seeks to address the painful tissue. 

Gunn IMS was developed by Dr. Chan Gunn of Vancouver. It is based on a law of science - Cannon's law of denervation supersensitivity. This law states that problems in muscles, and in fact all the tissues of the body, can be caused by problems in the nervous system. Nervous system problems make many tissues in the body very hypersensitive and dysfunctional. Gunn IMS addresses the nervous system, via the muscles, to relieve body pain.

What causes dysfunction in nerves?

Nerves can dysfunction for many reasons. A common cause of nerve dysfunction is physically compressing or stretching a nerve. This often happens around the spine because of poor posture or wear-and-tear changes in the discs and joints.  This can also happen throughout the body when tight muscles compress or stretch nerves. 

What happens when nerves are compressed or stretched?

Muscles contract and relax because nerves send electrical signals to them. Compressing or stretching a nerve changes the electrical signals sent to muscles. This makes the muscles tight, sensitive, and eventually painful. Altered electrical signals can also lead to problems in other tissues like joints, tendons and fascia. This is not only mechanically caused by tight nearby muscles, but also due to direct changes in the health of these tissues.
How can you tell if nerves are dysfunctioning?

You can’t tell if nerves are dysfunctioning through X-rays, CT scans or MRIs. Gunn IMS practitioners use a thorough physical examination to look for subtle signs of nerve dysfunction. These subtle signs include tight/tender muscles, muscle weakness, changes in skin temperature, changes in sweating, and changes in hair and nail health. This unique assessment allows the therapist to determine which nerves are dysfunctioning. With this information the therapist can plan a treatment strategy, using dry needles, to improve the function of the nerves.

What is the goal of Gunn IMS?

The goal of Gunn IMS is to help any nerves that are dysfunctioning to function better again. When nerves are functioning better, they deliver more normal signals to the muscles and all the other tissues they supply. This means that affected muscles become less tight and tender, and all the tissues that are linked to them (joints, tendons, fascia, etc) can function better too. This also will lead to less pain. 

Why are dry needles used?

Dry needles stimulate the nervous system when they are inserted into the body, especially when they are inserted into muscles. They stimulate the nervous system in a way that helps muscles to relax and become less painful and tender. This then helps any linked joints, tendons or fascia that are affected to be less painful too. When dry needles are inserted into muscles, they also stimulate the nervous system in a way that actually makes overactive nerves less active. This, in and of itself, helps all the tissues the nerve supplies to function more normally and be less painful. 

Who can benefit from Gunn IMS?

Gunn IMS can be very effective intreating many types of painful conditions in the muscles, joints, tendons, fascia and nerves. Some examples are low back pain, neck pain, “tennis elbow”, “golfer’s elbow”, sciatica, knee pain (“patellofemoral syndrome”/”chondromalacia patella”), shoulder pain (“rotator cuff syndrome”), hip pain (“IT band syndrome”, “piriformis syndrome”), and “myofascial pain syndrome”.

Which practitioners offer Gunn IMS?
UBC Gunn IMS training is only offered to registered physiotherapists and medical doctors.


What Our Clients Say

I was a patient several years ago and found that the IMS worked great on my problem at that time. So I returned after slipping on some ice. The assessment was more thorough than my medical doctor and the feedback for physio exercises was excellent. It will take some time, but I am already feeling the results. Thank you!!!
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