MyoTrac Infiniti
™
User Guide
38
The MyoTrac Infiniti comes with a number of pre-defined EMG-Stim Scripts for you to use. To
select one, choose the body area that you are going to be working with and it will show you a list of
scripts that are applicable to that body area. Alternatively, use the Custom Wizard to define your
own script following the on screen instructions. It is possible to save up to five custom EMG-Stim
scripts on board the device. Please consult the clinical guide for further information.
Types of EMG-Stim
There are two different types of EMG-Stim sessions that can be used on the MyoTrac Infiniti: EMG-
Triggered Stim (ETS) sessions and Alternating EMG-Stim sessions. Since these modes involve
the measurement of SEMG and delivery of electrical stimulation, the MyoTrac Infiniti uses the
same electrodes for stimulation and for SEMG, thus making it possible to direct the stimulation to
the same place as the SEMG was been measured. EMG-Stim sessions are run as Script Sessions
and no data is recorded.
What is an EMG triggered Stim session?
An SEMG triggered Stim session is the combination of the two complementary modalities to form a
third treatment possibility. The client’s own volitionally activated SEMG is used as a guide to
determine when to automatically stimulate. This combination of passive and active rehabilitation
elements could be considered as getting the best of both worlds.
Note:
EMG triggered STIM is not available for incontinence application
.
Features of an EMG triggered Stim session
Trigger Modes:
Depending on the context, stimulation can occur either when crossing above threshold or when the
signal falls below the threshold. When the trigger is above threshold, it can be referred to as
“reward” mode. When the target threshold has been reached, an electrical impulse is delivered to
the patient in order to complete the contraction. This mode motivates the patient and involves
them in the rehabilitation process. When the trigger is set to activate below threshold, it can be
referred to as “assistance” mode. When the patient is unable to hold the contraction for a long
enough duration using this mode will assist them in finishing the contraction. The trigger mode can
be set when customizing a script session. In the case of a predefined script session the trigger
mode is already selected and can be verified by checking the script information.
Threshold Modes:
This threshold can be set either by the user (manual) or by the system itself (automatic). Automatic
threshold mode is different for trigger above threshold and trigger below threshold. When the
stimulation is triggered below threshold, then during the first 3 activities of a session (i.e. work or
fast-flick), the threshold that the patient is able to reach is automatically calculated and displayed.
The patient must then continue to reach that target throughout the remainder of the session. When
stimulation is triggered above the threshold then the threshold will be adjusted throughout the
session.
Script Structure
SEMG triggered Stim sessions are conducted in a Script format. A Script takes the form of a
number of work and rest steps. During a work step, the MyoTrac Infiniti will guide the client to
activate the muscle being monitored. In addition to the signal displayed on the graph we can also
see the trigger threshold defined at setup time. If during the work period the signal reaches the
trigger threshold for a time greater than the pre-determined delay period, then the stimulation is
triggered. This stimulation is delivered for the remainder of the work step. The rest step is just
