Ask the Book
Common questions about electrical stimulation for denervated muscle
The answers below are drawn from the book. For anything more specific, open the AI assistant — it answers from the book’s evidence base and links back to the relevant chapters so you can check the sources.
What is denervated muscle?
Denervated muscle is muscle whose nerve supply has been damaged or lost. Without signals from its motor nerve, the muscle cannot contract voluntarily and begins to atrophy. This process is different from disuse atrophy — denervated fibres shrink more quickly, and the tissue gradually changes in ways that affect blood supply, skin quality over the area, and long-term function.
Read: What has happened to your muscles→How is electrical stimulation for denervated muscle different from NMES or FES?
Conventional neuromuscular electrical stimulation (NMES) and functional electrical stimulation (FES) activate the motor nerve, which then triggers the muscle. Denervated muscle has no functioning motor nerve to stimulate, so the current must reach the muscle fibres directly. This requires much longer pulse widths and higher intensities than standard clinical or consumer devices can deliver.
Read: How electrical stimulation works→What is the RISE programme?
RISE was a European research programme that studied home-based electrical stimulation for people with long-term denervation following complete lower motor neuron spinal cord injury. Over two years, participants recovered on average around 35% of muscle mass, a quarter achieved supported standing, and the protocol was shown to be safe for daily home use.
Read: What the research shows→Can electrical stimulation help after years of denervation?
Yes — this is one of the more surprising findings from the published research. Improvements have been reported in people with up to nine years of prior denervation, not only in the first months after injury. Outcomes vary with individual factors, and the book is honest that response is not universal, but long-standing denervation is not an automatic barrier.
Read: What the research shows→Is electrical stimulation of denervated muscle safe?
Across the published research covering several hundred participants followed over years, no serious adverse events have been reported. Minor skin irritation under the electrodes is the most common issue and is usually managed with electrode placement and skin care. Stimulation is not recommended in specific situations such as active infection or over implanted electronic devices without clinical advice.
Read: Honest answers to common concerns→How often do I need to do the stimulation?
Typical home protocols involve training twice a day, five days a week, with sessions of around 30–60 minutes. Consistency matters more than intensity: atrophy took months to develop, and recovery is measured in months to years. Skipping sessions regularly or using parameters below what the muscle requires will not produce meaningful change.
Read: Your home programme→Can I use a standard TENS unit?
No. TENS (transcutaneous electrical nerve stimulation) devices are designed to modulate pain and deliver pulses that are far too short to activate denervated muscle fibres. Conventional NMES devices have the same limitation. Stimulating denervated muscle requires specialist equipment capable of long pulse widths and higher currents, combined with larger electrodes suited to the application.
Read: Understanding the equipment→Why does specialist stimulation equipment cost so much more than a consumer device?
The parameters needed for denervated muscle (long pulse widths, higher currents, reliable waveform shaping) require medical-grade electronics, safety certification, and clinical validation. Volumes are also small compared with consumer TENS units. The result is a price difference measured in thousands rather than tens of pounds, which is why funding routes such as medico-legal settlements and personal budgets are common.
Read: Why specialist equipment costs what it does→What conditions cause denervated muscle?
The most common causes are complete spinal cord injury that damages the lower motor neurons supplying a muscle group, peripheral nerve injuries from trauma or surgery, cauda equina syndrome, facial nerve palsy, and some progressive neuromuscular conditions. The mechanism and prognosis differ by cause, and several chapters address specific conditions directly.
Read: How nerve injury and recovery work→What outcomes can I realistically expect?
Outcomes are individual. The book is explicit that full recovery of function is rarely achievable once motor neurons are lost. What is reported in the research and in practice includes meaningful preservation or partial recovery of muscle bulk, improved skin quality over bony prominences, reduced spasms in mixed lesions, better tolerance of sitting and transfers, and — in selected cases — supported standing. Assessment with an experienced clinician is essential before setting expectations.
Read: Honest answers to common concerns→
Not the question you needed?
The AI assistant can answer more specific questions using the full text of the book. It cites the chapters it draws from, so you can verify the answer yourself.