What You Will Learn
- What happens during an assessment appointment
- How your clinician determines whether your muscles are denervated
- What contraindications are checked
- How treatment goals are set
1. What the Assessment Is For
Before any treatment begins, your clinician needs to understand your individual situation. Is it safe for you to use electrical stimulation? The assessment determines whether electrical stimulation would be effective for you, which type of stimulation you need, what realistic expectations to set, and whether you are ready for the commitment that effective treatment demands.
This is not a box-ticking exercise. It is the clinical foundation that shapes everything that follows: the device, the settings, the programme, and the goals.
2. Determining Whether Your Muscle Is Denervated
The first and most important question is: is this muscle denervated, innervated, or somewhere in between? The answer determines everything.
Your clinician may perform a strength-duration test. This involves placing an electrode on the muscle and delivering individual pulses of varying durations, starting long and gradually shortening. At each duration, the current is increased until a contraction appears (or until no contraction can be produced).
Here is what the test reveals:
- If the muscle responds only to very long pulses (longer than 10 milliseconds), regardless of the current strength, it is denervated. It needs the specialist RISE protocol or equivalent with long pulse durations.
- If the muscle responds to a brief pulse (around 1 millisecond or less) at a moderate current, the nerve to the muscle is intact, and standard electrical stimulation is appropriate.
- If the muscle falls somewhere in between, it may be partially denervated or recovering, and the approach will be adapted accordingly.
This test is performed on each muscle group individually because different muscles in the same limb can have varying degrees of denervation. This is particularly common in spinal cord injuries and brachial plexus injuries.
3. Understanding Your Type of Injury
Your clinician will also determine whether your injury involves upper motor neuron damage, lower motor neuron damage, or both.
An upper motor neuron injury (such as a stroke or a thoracic-level spinal cord injury) disconnects the brain from the muscles, but leaves the nerves to the muscles intact. The muscles are paralysed because they receive no voluntary command, but they remain innervated. Standard FES and NMES can activate these muscles because the nerve remains intact.
A lower motor neuron injury (such as a conus or cauda equina injury, or a peripheral nerve injury) damages the nerves themselves. The muscles have lost their nerve supply directly. Standard stimulation produces no response at all. These muscles need the specialist protocol.
Many people have both types, sometimes even in different muscles of the same limb. A person with a T12/L1 spinal cord injury, for example, may have some muscles that respond to standard stimulation and others that need a specialist approach. This is why the assessment tests each muscle individually rather than making assumptions based solely on the injury level.
4. Safety Screening
Your clinician will check for conditions that might affect the safety of electrical stimulation for you.
Conditions where stimulation should not be used include:
- Cardiac pacemakers or implantable defibrillators (the electrical field could interfere with the device)
- Active blood clots (muscle contractions could dislodge a clot)
- Active cancer at the treatment site
- Open wounds or active skin infections at the electrode site
Conditions that require extra care include:
- Metal implants (pins, plates, screws, joint replacements). These are generally not a problem for surface electrical stimulation, despite what you may have been told. Research has shown no significant heating or corrosion with standard treatment. The genuine concern applies to high-frequency heating treatments like shortwave diathermy, not to the type of stimulation described in this book.
- Reduced sensation. If you cannot feel discomfort, visual monitoring of the skin becomes especially important.
- Fragile skin or a history of pressure injuries. Electrode placement must avoid compromised areas.
- Risk of autonomic dysreflexia (for spinal cord injuries above T6). This does not prevent treatment but requires specific precautions, described in Chapter 11.
An important note: if you have previously tried electrical stimulation and it did not work, your clinician will explore whether the right equipment and settings were used. In many cases, the device was wrong, not you.
5. Setting Realistic Goals
Goal-setting matters more than you might think. Research shows that people who understand what they are working toward and why the process takes time are far more likely to sustain the daily commitment that this treatment requires.
Your clinician will discuss two categories of benefit, depending on your situation.
If your denervation is permanent (for example, from a complete conus or cauda equina injury), the primary goals are to maintain and improve tissue health: preserving muscle mass that cushions bones and reduces the risk of pressure injury, maintaining skin quality and circulation, and improving the appearance of your limbs.
These are not consolation prizes. For people at high risk of pressure injuries, tissue preservation is a genuine clinical priority that can prevent serious, even life-threatening complications.
If nerve regrowth is expected (for example, after a peripheral nerve injury or nerve repair surgery), the primary goal is to maintain your muscle in the best possible condition until the regrowing nerve arrives. The better the muscle's condition at the time of reconnection, the better the functional outcome.
Goals are typically documented as:
- Short-term (first 3 to 6 months): prevent or reverse muscle wasting, improve circulation, establish a sustainable daily routine, achieve visible muscle contractions
- Long-term (6 months onward): measurable increase in muscle size, improved tissue quality, shift in strength-duration test results, maintenance of skin health, and, where realistic, functional milestones
These goals will be reviewed at regular intervals and updated as you progress.
6. Assessing Your Readiness for Home Treatment
Because this treatment requires daily home sessions, your clinician will also assess whether you are practically ready.
- Can you (or your carer) safely apply the electrodes, operate the device, and manage a session? If hand function is limited, carer involvement may be essential.
- Do you understand the treatment, the importance of consistency, and the signs that something needs attention (such as skin irritation or equipment problems)?
- Is your home environment suitable? A space for treatment, access to power, and safe storage for equipment.
- Do you have access to ongoing clinical support? You should never feel entirely on your own.
- Are you ready for the commitment? This is a significant daily commitment, typically 30 minutes per muscle group, five to six days per week, sustained over months. If your circumstances make this unrealistic right now, your clinician may suggest deferring or developing an adapted programme.
7. The Assessment Report
Your clinician will produce a structured report covering everything discussed above. This report serves as the baseline against which all future progress is measured. It also supports funding applications when equipment costs are covered by a case-managed situation or an insurer, and provides a clear record for any other clinicians involved in your care.
Chapter Summary
Assessment determines whether you are suitable for denervated muscle electrical stimulation and, if so, which approach to use. The strength-duration test is the most important element, revealing the denervation status of each muscle individually. Your clinician distinguishes between upper and lower motor neuron injury to select the right stimulation approach, screens for contraindications, and sets realistic goals that distinguish between tissue health maintenance and functional recovery. Practical readiness for home-based treatment is evaluated, and a structured report documents the starting point for your programme.