Meralgia Paresthetica (MP) is a sensory neuropathy that causes tingling, numbness, and burning pain in the outer thigh. The condition occurs when the Lateral Femoral Cutaneous Nerve (LFCN), a pure sensory nerve, becomes compressed or entrapped as it passes from the pelvis into the thigh, most commonly near the inguinal ligament. Although MP symptoms are distinct—purely sensory and often unilateral—they frequently overlap with other disorders, making accurate diagnosis challenging. Distinguishing MP from these “mimic” conditions is important because the treatments for nerve root compression, localized joint issues, and systemic nerve disease are fundamentally different.
Conditions Stemming from the Spine
Symptoms originating from the lumbar spine are frequently confused with Meralgia Paresthetica. The most common example is lumbar radiculopathy, often called a pinched nerve, involving the L2 or L3 spinal nerve roots. Since these roots contribute to the formation of the LFCN, compression at the spinal level can replicate the pain pattern felt in the thigh. Radiculopathy typically presents with back pain or pain radiating below the knee, which MP almost never exhibits. Unlike MP, radiculopathy includes motor symptoms (muscle weakness or reflex changes) and may cause positional discomfort, worsening with spinal extension.
Localized Musculoskeletal Mimics
Conditions affecting the hip joint and surrounding structures can produce pain mistakenly attributed to nerve compression. Trochanteric Bursitis, a common cause of lateral hip pain, involves inflammation near the greater trochanter. Bursitis pain is localized directly over the hip bone, described as sharp or aching, and is reproduced by direct pressure or specific hip movements. This differs markedly from the neuropathic burning or tingling of MP, where pain is purely a skin sensation, often hypersensitive to light touch. Hip Osteoarthritis causes deep, mechanical pain, typically in the groin or front of the thigh, related to joint degeneration rather than nerve entrapment.
Metabolic and Generalized Nerve Disorders
Systemic diseases causing widespread nerve damage (polyneuropathies) must be distinguished from the focal nerve entrapment of Meralgia Paresthetica. Diabetic Neuropathy is the most frequent metabolic cause that can mimic or contribute to MP symptoms. While MP is a mononeuropathy affecting only the LFCN, diabetes causes a generalized nerve disorder often beginning symmetrically in the feet. If thigh symptoms are bilateral or accompanied by numbness or pain in the hands and feet, a polyneuropathy is more likely than MP. Other generalized conditions, such as chronic alcoholism, hypothyroidism, or nutritional deficiencies, can also lead to polyneuropathy affecting the LFCN, requiring laboratory investigation, as treating the underlying systemic disease is crucial to prevent further nerve damage.