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Nerve Conduction and Electromyography

What we do

Nerve Conduction Studies (NCS) and Electromyography (EMG) are diagnostic tests that can identify problems with nerves and muscles. They are often helpful in diagnosing:

  • nerve injuries
  • compressed nerves in the spine or limbs (for example, carpal tunnel syndrome)
  • dying back of the nerve endings in the feet (peripheral neuropathy)
  • motor neuron disease
  • myasthenia gravis
  • other diseases of the muscle.

Preparing for your appointment

In advance of the test please tell us if you:

  • have a cardiac pacemaker or implantable defibrillator, and send a copy of the pacemaker card that shows the device make and model to: Department of Clinical Neurophysiology, Fourth floor, Ruskin Wing, Denmark Hill, London, SE5 9RS.
  • are on anticoagulation medicine to thin the blood, such as warfarin
  • if you have a blood disorder that increases your risk of bleeding, such as low platelets or haemophilia.
  • are taking pyridostigmine (Mestinon) tablets. If you are being tested for myasthenia gravis you may need to stop taking the tablets the night before your appointment.

On the day of your appointment

  • Avoid applying moisturising cream or lotion to your arms or legs, as this interferes with the test recording.
  • Keep jewellery to a minimum – avoid wearing any, if possible
  • Wear loose clothing, so the clinician can access the tops of your arms and tops of your legs. You may need to remove some clothing for the tests to be performed.
  • Bring your appointment letter and a list of any medicines you are taking.

At your appointment

You will be seen by a doctor (either a specialist registrar or a consultant) or by a clinical physiologist technician. They will ask about your symptoms and explain the test. Usually the test involves two parts – nerve conduction studies first, and then EMG. But you may only need one of these and the decision will be made by the clinician assessing your symptoms. The tests usually lasts about 30 minutes.

Nerve conduction studies are performed by applying small electrical pulses to different nerves, and recording how your nerves and muscles respond using pads resting on your skin. The pulses can feel uncomfortable at times, and make your muscles twitch, but most people tolerate the test with no problems. Many people who have used a TENS machine say it feels very similar.

EMG records the natural electrical activity inside one or more of your muscles by placing a tiny needle in them.

More information is on the British Society for Clinical Neurophysiology website.

After your tests

After the procedure you may leave for home immediately. The test results will be sent in a report to the doctor who referred you. When you next see that doctor they will discuss the results with you.


Fourth floor, Ruskin Wing, King’s College Hospital, Denmark Hill, London, SE5 9RS

Contact Details

Conditions we treat

Nerve conduction studies and EMG are diagnostic tests for peripheral nervous system disorders. The can be useful for diagnosing conditions such as:

  • entrapment syndromes (for example, carpal tunnel syndrome, ulnar neuropathy)
  • polyneuropathy (for example, in diabetes patients)
  • traumatic nerve injury
  • brachial neuritis
  • myopathy
  • neuromuscular junction disorders (for example, myasthenia gravis).

We accept referrals from GPs, physiotherapists and other hospitals. We treat both adults and children.

What is required before referring a patient

Pyridostigmine: If the test is for myasthenia gravis or other neuromuscular junction problems, pyridostigmine should be stopped 12 hours before the test assuming it is safe to do so. Please instruct the patient and also tell us.

Booking a patient at King’s

Routine Referrals

Complete the relevant referral form (below), or write a referral letter including the following information, and email it to [email protected]:

Referrer details: Name, job title, name of GP practice/Hospital and department

Patient details: Name, address, DOB, NHS number, phone number(s)

Clinical information needed:

  • Specify the question to be answered.
  • Date of onset (particularly important in acute onset conditions).
  • Describe the presenting complaint and medical history.
  • Confirm whether or not the patient has diabetes.
  • List medications taken.
  • Details of relevant lab results. For example, give actual creatine kinase levels instead of a general description such as “raised”.
  • Risk of bleeding/bruising (for example, anticoagulation, low platelets, haemophilia)?
  • Does the patient have a cardiac pacemaker or implantable defibrillator? If they do, specify the make and model.
  • whether or not there are infection control issues associated with the patient (for example, MRSA, C-diff, VRE).
  • Pyridostigmine: If the test is for myasthenia gravis or other neuromuscular junction problems, pyridostigmine should be stopped 12 hours before the test assuming it is safe to do so. Please instruct the patient and also tell us.

Emergency Referrals

Not applicable

Other Queries

Email: [email protected]
Phone: 020 3299 3151 or 020 3299 1658

Referral forms

TitleFile SizeLink
Electromyography and Nerve Conduction referral form866 KB

Key Clinical Staff

Name Role
Mr James Burge Consultant Clinical Neurophysiologist
Dr Doreen Fialho Consultant Clinical Neurophysiologist
Dr Alistair Purves Consultant Clinical Neurophysiologist
Mr Jordi Serra Consultant Clinical Neurophysiologist