Following on from a previous article about the benefits of FES cycling for spinal cord injury (SCI) patients, this article looks at how to control the low-level risks and reviewing the therapy sessions.
An essential factor to keep in mind when considering the use or prescription of a FES cycling device, is that FES uses electrical currents to elicit muscular contractions. Whilst these are considered as low-level voltages and currents, they are still more than sufficient to cause damage to the individual if used incorrectly, especially in the case of individuals with neurological injury or illness who suffer reduced sensation of awareness.
A specific example from spinal cord injury is the risk of Autonomic Dysreflexia (AD) in individuals with injuries above the level of T6 resulting from a lack of sympathetic control to noxious stimuli. When completing FES cycling, gluteal stimulation can often result on a noxious stimulus which, if set at too high a level can lead to an attack of AD.
To control for this, a reduction in the stimulation pulse width (i.e. reducing affect nerve stimulation) is required. A key feature of the RT300 is the ability to set different pulse widths to each channel, meaning that a lower pulse width can be applied to the gluteals to minimise the risk of AD, whilst still applying higher (longer) pulse widths to the thigh musculature (or whichever other muscles are targeted) to enhance the effectiveness of the therapy session.
Review and amend therapy sessions as required
Due to the presence of neuroplasticity in our nervous system, the sensitivity of the body’s response to stimulation can change over time. With the combined use of the SAGE software enabled RT300 and the employment of full time clinical specialists, Cyclone Technologies are in a unique position to provide reviews and amendments to therapy sessions as they are required.
The flexibility in control of stimulation that is offered by the RT300 is fundamentally due to the fact that it is a fully integrated FES cycle, as opposed to an active/passive cycle with an FES option. This means that the scope of interaction between the application of stimulation and output on the cycle is expanded beyond the simple trigger of stimulation at the correct point in the cycle.
The SAGE software controls a constant interaction between stimulation level, pedalling speed and resistance to ensure that a patient receives the correct level of stimulation to overcome the resistance and maintain a targeted speed. Should speed reduce below the targeted level, concurrent increases in stimulation intensity and reductions in resistance restore the required speed without any action being required from the patient. Beyond the functionality of the integrated FES system, the RT300 is the only FES ergometer to perform constant stimulation checks by assessing cable integrity and electrode attachment to ensure that the desired current parameters are being delivered throughout the therapy session.
Long term, home-based rehabilitation strategy
This document details key factors associated with the rehabilitation needs of SCI patients, and how the unique features of the RT300 provide for these needs in a compact device suitable for home use. The primary message is to consider that the users of an FES cycling machine are from a clinical population requiring treatment and rehabilitation, not simply ‘exercise’ and as such the RT300 provides the ideal foundation to develop long-term home based rehabilitation strategies, that are safe, stimulating and effective.