Meralgia Paresthetica aka Roth’s Disease aka Lateral Femoral Cutaneous Nerve (LFCN) syndrome is a condition we see from time to time. The patient tends to present with pain in the lateral thigh that almost feels like an itchy feeling. The discomfort can be anything from burning pain to tingling. The pain is not a deep pain but is superficial. This means you only feel it on the outside of the thigh vs. deep in. It can be very bothersome and it is certainly annoying enough that people will go to find a solution. Left untreated, it tends to get worse with time.
The cause of the condition can be due to anything that involves compression in the groin area (wearing tight pants too often), complications due to hip region surgery, pregnancy, being overweight, having weak gluteal musculature, and performing too many hip flexor exercises, just to name a few. There are several studies that examine the course of the LFCN and it has been discovered that there are several possible locations and branches of the nerve. The consensus is that the nerve gets compressed under the inguinal ligament (see photo right). After it courses under the inguinal ligament, it runs on top of the sartorius muscle where it splits into an anterior (front) and posterior (back) portion. The anterior branch goes to the skin of the anterior and lateral thigh and the posterior branch pierces the Tensor Fascia Lata and then goes to the middle of the thigh. It is possible that since the nerve contacts the Sartorius muscle that this muscle (one of the lesser known hip flexors that also externally rotates the hip and bends the knee) can help create problems as well. The great thing about Meralgia Paresthetica is that it can usually be treated successfully by addressing the involved structures. The problem is developed by some type of imbalance, and being such, when the cause of the problem is eliminated, the patient can recover nicely. Only in the rarest of situations is surgery necessary.
It is imperative to always address the spinal component in the mid/upper lumbar spine as the L2/L3 region is where the nerve begins. It is also important to be sure that the pelvis and hip joints are moving properly. We have to remember that a problem on the opposite side could cause compensatory problems on the involved side. Joint dysfunction in the lumbar spine, hips, and/or the pelvis can contribute to the problem. Adhesions in the region the where the nerve passes under the inguinal ligament must be addressed and of course, the Sartorius muscle must be assessed to be certain that it is not contributing to any of the compression.
The biggest problem with the LFCN is that it is usually misdiagnosed as something else. Too many times, due to the neurological presentation of tingling/burning pain/numbing, doctors think that the problem involves a ‘pinched nerve’ at the spine level. The most important thing to remember about Meralgia Paresthetica is that the discomfort is ALWAYS superficial and on the lateral portion of the thigh. If the tingling/burning pain is deep in your leg, the problem does not involve the LFCN.
If you or someone you know develops lateral thigh tingling/burning/numbing, or otherwise describes the discomfort as an itch that simply will not go away no matter how much they scratch it, it might be a good idea to get assessed for Meralgia Paresthetica. Be sure to consult specifically with a sports chiropractor or sports physical therapist who has proper training in extremity injuries, Active Release Techniques, Graston, and other advanced soft tissue training. The condition can be corrected without the need of medical intervention, especially if it is addressed early.