SEPALS-1 Surface EMG as a tool to fast-track ALS diagnosis
Research type
Research Study
Full title
SEPALS-1: Surface Electromyography as a tool to fast-track diagnosis in Patients with Amyotrophic Lateral Sclerosis (Clinical Diagnosis Workstream)
IRAS ID
357517
Contact name
James Bashford
Contact email
Sponsor organisation
Vice President (Research and Innovation)
Duration of Study in the UK
3 years, 5 months, 28 days
Research summary
Amyotrophic Lateral Sclerosis (ALS) is a progressive neurological disorder that causes to loss of motor nerve cells supplying different muscles in the body. Diagnosing ALS early remains a major challenge, as initial symptoms—such as muscle twitching, cramping, or weakness—can resemble other conditions. On average, it takes about a year from symptom onset to reach a confirmed diagnosis, which can delay access to specialist care and clinical trials.
This study will recruit 170 people newly referred to neuromuscular centres at King’s College Hospital or Newcastle Hospitals NHS Foundation Trust for routine investigations of motor nerve symptoms. While many will present with symptoms that raise clinical suspicion, not all participants will go on to receive a diagnosis of ALS,
The aim of this research is to evaluate whether a non-invasive technique called high-density surface electromyography (HDSEMG) can help identify ALS earlier and more accurately. HDSEMG uses grids of 32 or 64 small electrodes placed on the skin over specific muscles—such as those in the hand, arm, and leg—to record muscle activity, including involuntary twitches- also known as fasciculations- and motor unit behaviour. Unlike traditional needle-based tests, HDSEMG is pain-free, well-tolerated, and suitable for repeated use.
Each participant will complete a single, one-hour HDSEMG session and be followed for 15 months to confirm their final diagnosis. The main goal is to determine whether early fasciculation patterns predict a future ALS diagnosis. We will also compare HDSEMG with standard needle EMG and assess whether early muscle activity patterns relate to disease progression.
If successful, this method could be incorporated into diagnostic pathways to accelerate diagnosis, reduce unnecessary investigations, and alleviate the stress and uncertainty faced by patients and families during the diagnostic process.REC name
North West - Greater Manchester West Research Ethics Committee
REC reference
25/NW/0278
Date of REC Opinion
17 Sep 2025
REC opinion
Favourable Opinion