An EMG and nerve conduction study (NCS) checks whether a nerve in your low back or leg is pinched or hurt. A physician performs the test and writes the report. Pain, numbness or weakness down the leg can come from a pinched nerve in the back or from a nerve in the leg.
Your physician orders this test. You only get it if it is ordered for you.
What is nerve test of the leg (EMG/NCS)?
An EMG and nerve conduction study (NCS) checks whether a nerve in your low back or leg is pinched or hurt. A physician performs the test and writes the report.
How does it help?
Pain, numbness or weakness down the leg can come from a pinched nerve in the back or from a nerve in the leg. This test shows where the problem is, so the treatment goes to the right place.
What does it feel like?
Small pads send quick electrical taps along the nerve; it feels like a snap. Then a thin needle checks a few muscles, which feels like a pinch. Most people go back to normal activity right after.
How do you get ready?
Wear loose pants or shorts. Do not put lotion on your legs that day.
What should you tell us first?
- Tell us first if you take blood thinners, have a pacemaker, or have swelling or skin problems in the leg
How long does it take?
About 30 to 60 minutes.
What to remember
- It finds where a nerve is hurt and how badly.
- No lotion on your legs that day.
- Tell us about blood thinners or a pacemaker.
Show us you have it: Tell us how you will get ready on the test day. We go over it again at your next visit, and you can ask us to explain anything a second time.
Read more: how an EMG is done, options before back surgery.
Other tests in the program
- Nerve test of the arm (EMG/NCS)
- CMAT (CardioMetabolic Assessment Test)
- Cognivue
- Kinetisense
- RQ (resting metabolic rate)
- VNG (balance and dizziness test)
This is part of our physician-directed physiotherapy program, where a physician orders and supervises every treatment and no treatment starts unless a physician is available right away.
Medically reviewed by Dr. Gurpreet Singh Padda, MD, MBA, MHP. Board Certified in Anesthesiology, Pain Medicine, Interventional Pain Management, Addiction Medicine, and Obesity Medicine. Last reviewed October 18, 2026.