Meralgia paresthetica is a localize sensory symptoms of the outer thigh that is caused by a compression of the Lateral Femoral Cutaneous Nerves or it is a pain or burning sensation felt over the anterolateral aspect of the thigh usually caused by compression of the lateral femoral cutaneous nerve [LFCN]
It is a mononeuropathy, meaning a single nerve is affected.
The lateral femoral cutaneous nerve originate from L2, L3 nerve root. It comes from the behind of the Psoas muscle and runs around the surface of the Iliacus muscle and under the inguinal ligament and unto the thigh just medio and inferal to the anterior superior iliac spine.
Lateral femoral cutaneous nerve supplies sensory innervation to the upper outer thigh. The LFCN carries only sensory symptoms, therefore, there is no motor symptoms associated with paresthetica.
Causes of meralgia paresthetica
- Tight pants
- Corset braces
- Obesity/weight gain
- Local trauma
- Injury is usually caused by compression as the nerve passes under the inguinal ligament
The LFCN of the thigh arises from the branches of the L2 and L3.
The LFCN becomes injured during
- Harvesting anterior iliac crest bone graft
- Ilioinguinal approach for acetabulum fixation
- Application of external fixation of the pelvis.
- Total hip replacement by anterior approach or smith-peterson approach.
The LFCN usually passes under the inguinal ligament approximately 2cm medial to the ASIS. Once outside the pelvis, the nerve splits and pierces the fascia, running over the lateral aspect of the thigh in the subcutaneous region and lies superficial to the Sartorius muscle.
The cause of the LFCN in the area of ASIS is variable, under ligament (common), over ligament, over and under ligament, and over iliac crest. The variations can cause entrapment of the nerve near the iliac crest causing Meralgia Paresthetica.
Recognizing the variability and their relationship of this nerve and its branches is important to avoid injury to the nerve. It is difficult to establish a safe zone of the nerve during surgical approaches to the acetabulum or the proximal femur.
Note: Disc herniation that affects the L2 & L3 nerve roots can also cause Meralgia paresthetica. Consider spine pathology when dealing with Meralgia Paresthetica.
Presentation of Meralgia Paresthetica
Patient present with:
- Abnormal sensation [dysaesthetica] (ie. There will be hypersensitivity over the anterolateral aspect of the thigh, patient will sometimes notice this sensitivity while placing their hand or car keys inside the pocket)
- Loss of sensation [anaesthesia and distribution of lateral femoral cutaneous nerve affect the skin of the upper outer thigh]
- Patient may describe symptoms as a burning, numbness, pins and needles, cold sensation, and localized hair loss.
- Aggravating factors: walking, standing, extension of the hip
- Alleviating factors: sitting down
- Clinical [history and physical examination]
- Investigation [ rule out other causes, nerve root compression in the spine, pelvic tumors]
- physical therapy
- anti-inflammatory medication
- weight loss
- strengthen abnormal muscles
- avoid wearing tight clothes and tight bands around the pelvic
- steroids injection
Physical therapy treatment
If you have any of the listed symptoms, it is important to have it assessed by a physical therapist or physiotherapist. The therapist will then be able to rule out any other conditions. They may also request for a scan (CT scan, MRI or X-ray).
At Esther’s Place Well-Being Hub, we design a therapeutic modality to best fit your recovery goals through:
- tri-planar psoas active stretch
- meralgia paresthetica nerve tensioner
- meralgia paresthetica nerve floss
- mini-band hip brid
We also help to prevent future occurrence of Meralgia Paresthetica after going through an assessment to determine if there is any possibilities.
Esther’s Place Well-being Hub, we make healthcare accessible and affordable to all, especially the aged.