Electrical Quantitative Sensory Assessment for chronic pain

An accurate at-home assessment for Failed Back Surgery Syndrome patients.


Chronic pain is not just debilitating, it has profound human and economic consequences.1 A Europe-wide survey2 found that neuropathic pain (caused by disorders to the nervous system) had a major impact on patients’ general activity, from mood and enjoyment of life, to their ability to work.

Post-surgery neuropathic pain, called Failed Back Surgery Syndrome (FBSS), is a persistent lower back or leg pain after a technically successful spine surgery. Sometimes there is no obvious cause.

To assess patients and develop an appropriate treatment plan, clinicians use spinal cord stimulation (SCS), where pain signals are interrupted before they reach the brain. However, 20% of patients don’t respond.2 A more accurate pain and sensory assessment is needed, which is where ESQA comes in.

Easing chronic pain with EQSA

Chronic Pain’s Electrical Quantitative Sensory Assessment (EQSA) system uses a portable stimulator, multi-field electrodesand a user interface to enable patients to assess FBSS in the home.

It delivers electrical stimuli to various body parts, targeting different nerve fibres to produce a range of sensations. Patients then use the interface to rate the level at which they can detect these different sensations.

This maps the pain across the body, increasing the accuracy of sensory analysis rather than the current process of filling in questionnaires and undergoing clinical examinations.

Bringing Chronic Pain to market by 2022

Using Chronic Pain at home will reduce the number of clinic visits during the supervision period of SCS by 30%. Vitally, healthcare professionals will have tools to assess pain or sensory disorders which allow better detection of nerve pain. This could aid diagnosis and help lower the SCS failure rate.

By reducing specialist visits by 25 to 30%, savings of more than €8 million in Spain could be achieved.

EIT Health’s support underpins a strong consortium of partners across business, research and education. Together the team are focusing on clinically validating Chronic Pain and making it market-ready within two years.


[1] A burden of illness study for neuropathic pain in Europe Clinicoecon Outcomes Res. 2016; 8: 113-126, published online 2016 Apr 27. Doi: 10.2147/CEOR.S81396 https://www.ncbi.nlm.nih.gov/pmc/articles/MC4853004/

[2] McDermott AM, Toelle TR, Rowbotham DJ, Schaefer CP, Dukes EM. The burden of neuropathic pain: results from a cross-sectional survey. Eur J Pain. 2006; 10(2):127-135

[2] According to Medtronic Inc, a global leader in medical devices, services and solutions, and leader in chronic pain treatment in over 160 countries worldwide.

[3] Multi-field electrodes are devices containing tens to thousands of micro electrodes that can both record electrical signals from nerves and deliver electrical stimulation to nervous tissue https://en.wikipedia.org/wiki/Microelectrode_array

Eukene Imatz Ojanguren
Neurorehabilitation area | Researcher | Fundación TECNALIA Research & Innovation