Femoral nerve pain, also known as femoral nerve dysfunction, can occur following damage to the femoral nerve. It usually results in a loss of sensation and movement in the legs, and this happens when the femoral nerve is compressed as it passes under the inguinal region – anterior to the iliopsoas muscle.
Femoral neuropathy usually goes away without treatment, but where symptoms don’t improve, medications and physical therapy can help.
Symptoms of Femoral Nerve pain:
The symptoms of femoral nerve pain depend on the extent of damage to the femoral nerve. Typical symptoms include:
- Pain over the front of the thigh
- Loss of power of knee extension and hip flexion
- Lower extremity muscle weakness
- Numbness, pain, burning, or tingling sensation in the medial aspect of the lower leg and anteromedial thigh
- Loss of muscle bulk of quadriceps
- Difficulty going up and downstairs
- Groin pain
- Stiffness in your hip joint
- Loss of knee jerk
- Atrophy of thigh muscles
What Causes Femoral Nerve pain?
The femoral nerve is the largest nerve of your lumbar plexus, and it controls the muscles that move your hip and straighten your leg. The nerve enters the femoral triangle after passing underneath the inguinal ligament, and is responsible for sensation in the lower leg and front of the thigh. Because of the location, damage to the femoral nerve is rare.
The most common causes of femoral nerve pain are:
- Direct injury
- Retroperitoneal haematoma because of anticoagulant medications
- Prolonged pressure on the femoral nerve
- Femoral nerve block
- Vascular procedures, such as arterial bypass and femoral artery catheterisation
- Femoral nerve compression or entrapment due to lumbar spine pathology (L2-L4), in the adductor canal or iliacus compartment and may also involve the saphenous branch
- Musculotendinous entrapment
- Prolonged lithotomy position (lying on your back with your legs flexed).
- Hip and pelvic surgeries like hysterectomy
- A pelvic fracture
Damage to the femoral nerve can also be a result of rare non-iatrogenic causes:
- Radiation injury
- Tight or heavy waist belts
- A broken pelvic bone
- Injury to the spine can narrow the gap where the nerve exits the spinal cord, causing pinching of the femoral nerve.
- Diabetes mellitus
Diabetes mellitus may cause compression to the femoral nerve due to fluctuations in blood sugar. Nerve damage affecting the hands, feet, arms, and legs is called peripheral neuropathy as typically involves important peripheral nerve. But this is a matter of debate whether femoral neuropathy is a form of diabetic amyotrophy or truly a peripheral neuropathy.
How Is Femoral Nerve pain diagnosed?
The diagnosis and treatment of femoral nerve pain depend on the symptoms you experience, but a doctor is likely to ask about the patient’s medical history, including any past surgeries and lifestyle risk factors.
1. Initial Tests:
Your doctor will perform a comprehensive physical examination to diagnose the cause of femoral nerve pain. The doctor will also test specific muscles to look for weakness, for example, smaller and weak quadriceps muscles on the front of the thigh. They will also ask you about the changes in your foreleg and at the front of your thigh, and monitor your knee reflexes. These initial tests will help the doctor assess whether symptoms involve just the femoral nerve, or if other nerves also contribute.
The following additional tests can be performed to further confirm the diagnosis:
2. Electromyography (EMG):
EMG records your muscles’ health and electrical activity and ensures that the nerves that control the muscles are active. EMG is performed to determine whether the response of muscles to stimulation is appropriate or not, and since nerves control and stimulate your muscles, any abnormality can be revealed by EMG.
3. Magnetic Resonance Imaging (MRI):
MRI scans detect the presence of any tumours, masses, or cancerous growths that could cause prolonged compression of the femoral nerve. An MRI scan can detect abnormalities of the body’s internal structures by using magnetic fields to generate detailed images.
4. CT Scan:
A CT scan can also detect abnormal vascular or bone growths, by producing different images of the body’s structures that are being scanned by combining computer technology and x-rays.
5. Nerve Conduction Velocity (NCV) Tests:
NCV tests measure the speed of electrical signals moving through a nerve. When electrical signals travel through the nerves in a slow time, it indicates damage to the nerve being checked. Typically, the NCV test is performed at the same time as EMG.
What is meralgia paresthetica?
Meralgia paresthetica, is a type of specific femoral nerve dysfunction that impacts your lateral femoral cutaneous nerve. This particular branch of the femoral nerve gives feeling and sensation to your thigh’s skin.
Treatment Options for Femoral Nerve pain:
Treatment options depend on the underlying cause of femoral nerve pain, but the two most common are medications and physical therapy.
Medications for femoral nerve pain include corticosteroid injections to reduce swelling and inflammation in your leg. Conversely, painful and uncomfortable symptoms can be relieved by prescribed or over-the-counter pain medications.
Some healthcare providers may recommend a nerve block, which acts as a local anaesthetic to reduce femoral nerve pain by “turning off” the pain signals that pass through the femoral nerve.
If the femoral nerve pain is caused by a tumour or growth, surgery could relieve pressure on the nerve. Femoral decompression can also reduce compression on the femoral nerve and improve the flow of blood to the upper thigh .
It generally takes several months to fully recover from femoral nerve pain but six months are usually required for full recovery.
Preventing Femoral Nerve pain:
These lifestyle habits may also reduce the symptoms of femoral neuropathy:
- Lose weight if obesity or diabetes mellitus contribute to femoral nerve pain
- Keep your blood sugar in control.
- Avoid sitting for extended periods to reduce pressure on the femoral nerve
- Avoid tight clothing
- Exercise regularly to strengthen leg muscles
If left untreated, femoral nerve pain can lead to permanent damage or death of the femoral nerve. Sustained injuries are another example where femoral nerve pain goes unnoticed due to loss of sensation. In addition, the risk of falls are increased due to muscle weakness.
The Bottom Line:
Femoral nerve pain is a disorder characterised by damage to the femoral nerve, which results in pain, weakness, numbness, and paralysis of the legs. Femoral neuropathy can occur as a result of surgical procedures, direct injury, or any health conditions like diabetes mellitus. Treat femoral neuropathy and adopt certain lifestyle modifications to prevent further complications.
Frequently Asked Questions –
What does femoral nerve pain feel like?
The symptoms felt from a femoral nerve pain can be one of the following: altered sensation in the thigh, knee or the leg, numbness, bringing or pain along with the distribution of the femoral nerve. As well as changes in strength, and bucking knees.
Does femoral nerve damage go away?
In most cases femoral nerve pain with limited treatment, if the issues persist it is advised to seek the assistance of a physical therapist (physiotherapist or sports therapist)
How long does it take for a pinched femoral nerve to heal?
Recovery is achieved in around 70 % of femoral nerve patients with the recovery sometimes taking a year, although the patients may not be experiencing symptoms through the recovery.
Where is femoral pain felt?
Numbness and weakness from the trapped nerve is predominantly experienced in the front of the thigh.
- Ganu S, Mehta Y. Femoral compressive neuropathy from iliopsoas haematoma complicating dengue hemorrhagic fever. Asian Pac J Trop Med 2013;6:419–20. https://doi.org/https://doi.org/10.1016/S1995-7645(13)60052-8.
- Campbell, A. A., Eckhauser, F. E., Belzberg, A., & Campbell, J. N. (2010). Obturator nerve transfer as an option for femoral nerve repair: case report. Neurosurgery, 66(6 Suppl Operative), 375. https://doi.org/10.1227/01.NEU.0000369649.31232.B0
- Moore AE, Stringer MD. Iatrogenic femoral nerve injury: a systematic review. Surg Radiol Anat 2011;33:649–58. https://doi.org/10.1007/s00276-011-0791-0.
- Yi TI, Yoon TH, Kim JS, Lee GE, Kim BR. Femoral Neuropathy and Meralgia Paresthetica Secondary to an IliacusHematoma. Ann Rehabil Med 2012;36:273–7. https://doi.org/10.5535/arm.2012.36.2.273.
- Diabetic Neuropathy | NIDDK n.d. https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/nerve-damage-diabetic-neuropathies
- Minoo Hadjari Hollis. What are the signs and symptoms of femoral nerve entrapment? n.d. https://www.medscape.com/answers/2225774-32344/what-are-the-signs-and-symptoms-of-femoral-nerve-entrapment