EMG is the common abbreviation for electromyography. The “myo” part means muscle, so EMG means “electrical muscle writing” – where the electrical signal recorded from a muscle is made to write patterns on a video screen. Nerve Conduction Studies (NCS) are also done where an electrical stimulus is applied to the nerve and the electrical response is recorded further on down the nerve or from a muscle the nerve communicates with.

To be referred to our service, you would typically show signs or symptoms of nerve or muscle problems consisting of numbness, tingling, pain, weakness, or some combination of these. Such symptoms can have many causes, and it is the role of EMG and NCS to find evidence of muscle or nerve damage and to provide a diagnosis to the physician who referred you here, so that appropriate treatment can be given.

The most common diagnosis is a single “pinched nerve”, for example at the wrist (Carpal Tunnel Syndrome) or perhaps in the neck or lower back. We also often test people who have more widespread symptoms due to a problem with the nerves in general – quite common in diabetes, for example. Sometimes we are testing people for rarer conditions such as ALS or genetic disorders of the muscles and/or nerves. The reasons to come to the EMG lab are vast and varied and by no means limited to those we have listed here. Often our EMG test results show nothing abnormal, or the test results may point to a diagnosis quite different from that suggested by the physician who sent you, so EMG might spare you unnecessary or inappropriate treatments.

Aside from providing this primary service to the public, our clinic plays a key role in training Residents: These are doctors studying to become Neurologists or Physiatrists (Physical Medicine and Rehabilitation). We also introduce University of Ottawa students to EMG, we provide facilities to consult research in the field (through the Neuromuscular Centre at the Civic Campus and through the Rehabilitation Centre), and we participate in regional and national EMG teaching and review courses.

The Rehabilitation Medicine EMG lab is staffed by 10 physicians (all physiatrists), one registered EMG Technologist and is administered by the booking department at the Rehabilitation Centre.
The Neurology EMG lab is staffed by 9 physicians (6 neurologists, 2 physiatrists and 1 plastic surgeon) and 5 full or part time registered EMG technologists and is administered by physician administrative assistants and reception/booking clerks.

Clients are referred from a wide area of Eastern and Northern Ontario, Western Quebec, as well as Iqaluit by family physicians or by specialists (including, but not limited to, neuro, orthopedic or plastic surgeons, rheumatologists, other neurologists, other physiatrists).

• Referral form for Neurology EMG Lab
• Referral form for Rehabilitation Centre EMG Lab

An EMG test is usually done in two parts. First is the Nerve Conduction Study (NCS), done by an experienced technologist who applies recording electrodes to the skin near a specific muscle or nerve, then applies an electrical stimulus to the skin at one or more sites along the course of the nerve. An electrician might use a similar procedure when testing an electric circuit – putting a signal in one end of the wire and measuring what comes out the other end. The EMG machine shows the electrical response of the nerve or muscle on a computer monitor, giving an immediate indication of the health of that nerve.

The second part of the test, if judged necessary, is needle Electromyography (EMG). This part is often done by the physician and does not involve electric stimulation. Instead, an electrode resembling an acupuncture pin is inserted into muscle tissue where it acts as an antenna for recording electrical activity. Nerve and muscle diseases alter the pattern of electrical activity in muscles.

There are two types of appointments in the Neurology EMG Lab. One involves just testing and you are either booked for 30 or 45 minutes depending on the testing anticipated. The second, more common type of appointment involves testing plus a consultation with one of our neurologists or physiatrists. These appointments can be booked for 30 to 60 minutes. In the Rehabilitation Medicine EMG Lab, the appointments always include both testing and the consultation and can take from 45 to 60 minutes.

The tests are uncomfortable, but almost everyone tolerates them quite well. The electrical stimulation causes some discomfort, similar to that odd feeling you get in your little finger when you tap your “funny bone” at the elbow. The needle electrode also causes some discomfort, although it is typically less painful than an injection because nothing is being injected and the needles are very finely tapered and Teflon© coated. Note also that the needles are single use: each client gets a new one to eliminate the possibility of transmitting infections. After-effects of the testing may include some tenderness or slight bruising in the muscles that were examined by needle, and will not affect your walking, driving or any of your usual activities.

Eat normally and take your usual medications unless directed to do otherwise (If you are being tested for a possible Neuromuscular Junction disorder such as Myasthenia Gravis and have been prescribed a medication called Mestinon, you will be told to not take your dose(s) on the day of your test). Very few medications will affect the tests, but you should tell the EMG physician if you are taking aspirin or blood thinners (eg. Coumadin©), or if you have a form of hemophilia, because these might promote bleeding during the needle EMG study. If you are booked to see a physician for consultation in the EMG Lab, please bring a list of your medications and dosages.

If your symptoms are in your legs and you prefer not to wear one of our hospital gowns please bring a pair of shorts to change into. It is also recommended that you wear a short-sleeved shirt. Electrical stimulation and recording are improved if the skin is as clean as possible so it is best to not to use oily lotions prior to your visit. Lotions act as an excellent insulator and will interfere with the tests and prolong your discomfort. Out of consideration for hospital staff and other patients who may have sensitivities, please do not use perfume, cologne, after-shave or other fragrances on the day of your test.

If you are seeing a neurologist or physiatrist during your appointment, the results will be explained at the end of the testing. For all testing, a report will be dictated and it should be received by your physician within 2 weeks.