EMG and TMS Training Videos

 

JOVE Video Publication

We have published a JOVE video article showing how to set up the EMG and perform TMS, but you may need JOVE journal access from your institution to view it. Please note:

Determining the Functional Status of the Corticospinal Tract Within One Week of Stroke

 

Below are short videos showing how to set up the EMG recordings and position the TMS coil using a Neurosoft/MEGA-TMS system. The videos feature Sian McGee who is an Occupational Therapist that uses TMS to determine MEP status as part of routine clinical practice at Auckland City Hospital.

 

Skin Preparation

This 3 minute video shows the steps in locating the ECR muscle belly, preparing the skin, and applying the EMG electrodes. Note that you can use either skin preparation tape or an abrasive cream or gel to exfoliate the skin.

Ask the patient to extend their wrist with their fist closed if they are able. This can help identify the ECR muscle body and isolate it from the extensor digitorum muscle body. If the patient is unable to extend their wrist then the ECR muscle belly can be found by palpating the large brachioradialis muscle belly that runs along the radial (lateral) border of the forearm, and then rolling your fingers off to the extensors, which should lead to palpating the ECR muscle belly. The ECR muscle belly should be along an imaginary line running from the lateral epicondyle of the humerus to the styloid process of the radius. 

The FDI muscle body is located slightly proximal to the webbed space between the thumb and index finger on the dorsal side of the hand and can be palpated by having the patient abduct their index finger if possible.

 

Taping Electrodes

This 10 second video shows how to tape down the edge of the electrode over the FDI muscle belly, if it isn’t sticking well to the web of the thumb.

 

EMG Connections

This 2 minute video shows positioning of the ground strap and connecting of the EMG electrodes to the EMG system via the cables. Top tip: untangle the cables before you start preparing the patient.

 

Reducing Biological Noise due to Muscle Activation

This 30 second video shows repositioning of the arm to relax the ECR muscle and reduce biological noise due to muscle activation in the EMG trace. In this scenario, adding a pillow under the person’s arm helped them relax their muscles. Other strategies include asking the patient to drop their shoulders, or let their hand and arm feel heavy and fully supported by the pillow.

 

Initial Coil Position

This 2’30’’ video shows how to use anatomical landmarks to position the centre of the TMS coil over the primary motor cortex. Note that the centre of the coil is marked with a small square on its upper surface. This should be positioned over the inter-aural line, approximately 2 inches lateral to the vertex.

 

Coil Positioning Tips

This 1’10” video shows how to avoid coil positions that are too anterior, medial, or posterior, and will miss the person’s primary motor cortex.

 

Finding MEPs

This 1’20” video shows how to move the coil in small steps to check different coil positions, then increasing the stimulus intensity if no MEPs are observed. Note that MEPs are easily observed on the laptop screen in the background once the intensity is increased to 40%.

 

Coil Orientation Tips

This 40 second video shows some of the common problems that can occur with the orientation of the coil. It’s important to keep a consistent coil position and orientation, with the centre of the coil flat against the patient’s head.

 

Coil Angle Tips

This 20 second video shows how to hold the coil at the correct 30 to 45 degree angle.

 

Bilateral Facilitation

This 1’40” video shows how to ask the patient to perform bilateral facilitation. Testing is carried out with the patient at rest, but if no MEPs are observed with 100% stimulus intensity then it is important to facilitate their responses with attempted bilateral activation of the upper limb and shoulder muscles. This voluntary activity may allow you to observe MEPs and classify the patient as MEP positive.

 

Starting the Neurosoft Software

This 1’20’’ video shows how to start the Neurosoft TMS software, check the EMG signals, and check the electrode impedance.