• Femoral Nerve Block


    The femoral nerve starts at a nerve bundle in the lower back. It passes through the pelvic area and branches off as it travels down the leg to the foot. The nerve affects feeling and movement of the thigh, hip, and knee. A femoral nerve block decreases sensation in these areas.
    The Nervous System
    Nucleus factsheet image
    Copyright © Nucleus Medical Media, Inc.

    Reasons for Procedure

    Femoral nerve blocks are generally used for pain relief. You may also be given a femoral nerve block for:
    • Femoral neck or shaft fracture
    • Surgery on your leg

    Possible Complications

    There is a higher risk of falls after having a femoral nerve block because of decreased sensation in the leg. Falls can cause or worsen injury.
    Other problems from the procedure are rare, but all procedures have some risk. The doctor will review potential problems, like:
    • Blood clots
    • A local pocket of blood outside of the blood vessels—hematoma
    • Infection
    • Nerve or blood vessel damage
    • Atrial fibrillation
    • Additional surgery, which may needed after a fall
    • Pneumonia
    • Kidney failure

    What to Expect

    Prior to Procedure

    Before the procedure, the doctor may request the following:
    • Physical exam
    • Blood tests
    • Urine tests
    • Imaging tests, which may include x-rays, or an MRI or CT scan
    Current medications should be discussed with the doctor before surgery. Certain medications need to be stopped up to a week before your procedure.


    A local anesthetic will be used at the injection site before the block is delivered. It will numb the area. A sedative may also be give to encourage relaxation.

    Description of the Procedure

    This procedure may be done as treatment by itself or as part of your treatment.
    You will be asked to lie on your back. The doctor will locate the femoral nerve by feeling of the pulse from the femoral artery just below your pelvic area. The femoral nerve is located next to this blood vessel. An ultrasound machine may also be used to help guide the needle. The needle will then be inserted into the femoral nerve. More than one injection may be needed to get the needle into the correct position. You may feel your thigh muscle twitch when the nerve is stimulated by the needle. Once the needle is in the correct place, the anesthetic medication will be injected into the nerve.

    How Long Will It Take?

    15-20 minutes

    Will It Hurt?

    Local anesthesia will prevent pain at the injection site during the femoral nerve block. You may have some discomfort at the insertion site after the nerve block wears off.

    Post-procedure Care

    At the Hospital
    After the procedure, the hospital staff will monitor blood pressure and heart rate.
    At Home
    Transportation home and assistance at home will be needed until the anesthesia wears off.

    Call Your Doctor

    It is important to monitor your recovery. Alert your doctor to any problems. If any of the following occur, call your doctor:
    • Signs of infection, including fever and chills
    • Redness, swelling, pain, or discharge from the insertion site
    • Pain that does not go away with the medication you were given
    • Excess bleeding from the insertion site
    • Falls, especially if they result in injury
    • Residual tingling, numbness, weakness or shooting pain in your leg
    • Cough, shortness of breath, or chest pain
    If you think you have an emergency, call for emergency medical services right away.


    American Society of Anesthesiologist https://www.asahq.org

    Ortho Info—American Academy of Orthopaedic Surgeons http://orthoinfo.org


    Canadian Anesthesiologists' Society http://www.cas.ca

    When it Hurts to Move—Canadian Orthopaedic Foundation http://whenithurtstomove.org


    Anesthesia for hip and knee surgery. Ortho Info—American Association of Orthopaedic Surgeons website. Available at: http://orthoinfo.aaos.org/topic.cfm?topic=A00372. Updated March 2014. Accessed October 2, 2017.

    Femoral nerve block. New York School of Regional Anesthesia website. Available at: http://www.nysora.com/femoral-nerve-block. Accessed October 2, 2017.

    Sharma S, Iorio R, Specht LM, Davies-Lepie S, Healy WL. Complications of femoral nerve block for total knee arthroplasty. Clin Orthop Relat Res. 2010;468(1):135-140.

    Szucs S, Morau D. Femoral nerve blockade. Med Ultrason. 2010;12(2):139-144.

    Total knee arthroplasty. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T360995/Total-knee-arthroplasty. Updated July 17, 2017. Accessed October 2, 2017.

    Wright I. Peripheral nerve blocks in the outpatient setting. AORN J. 2011;94(1):59-74.

    Revision Information

    • Reviewer: EBSCO Medical Review Board Marcin Chwistek, MD
    • Review Date: 09/2017
    • Update Date: 07/01/2014
  • LiveWell personal health survey

    How healthy are you really? Find out – free.Learn more

    It's time to stop guessing. If you want to make some changes but just aren't sure how, the free personal health survey from LiveWell is a great place to start.

  • HeartSHAPE Spotlight

    At risk for a heart attack? Learn more

    Fight heart disease and prevent heart attacks. HeartSHAPE® is a painless, non-invasive test that checks pictures of your heart for early-stage coronary disease.

  • Calories and Energy Needs

    Calorie NeedsLearn more

    How many calories do you need to eat each day to maintain your weight and fuel your physical activity? Enter a few of your stats into this calculator to find out.

  • Ideal Body Weight

    Ideal Body WeightLearn more

    Using body mass index as a reference, this calculator determines your ideal body weight range. All you need to do is enter your height.

  • Body Mass Index

    Body Mass IndexLearn more

    This tool considers your height and weight to assess your weight status.

  • Can we help answer your questions?

    Wellmont Nurse Connection is your resource for valuable health information any time, 24 hours a day, seven days a week. Speak to a Nurse any time, day or night, at (423) 723-6877 or toll-free at 1-877-230-NURSE.