Ultrasound-guided Lateral Femoral Cutaneous Nerve Block in Meralgia Paresthetica

Abstract

Meralgia paresthetica is a rarely encountered sensory mononeuropathy characterized by paresthesia, pain or sensory impairment along the distribution of the lateral femoral cutaneous nerve (LFCN) caused by entrapment or compression of the nerve as it crossed the anterior superior iliac spine and runs beneath the inguinal ligament. There is great variability regarding the area where the nerve pierces the inguinal ligament, which makes it difficult to perform blind anesthetic blocks. Ultrasound has developed into a powerful tool for the visualization of peripheral nerves including very small nerves such as accessory and sural nerves. The LFCN can be located successfully, and local anesthetic solution distribution around the nerve can be observed with ultrasound guidance. Our successfully performed ultrasound-guided blockade of the LFCN in meralgia paresthetica suggests that this technique is a safe way to increase the success rate.

Concurrent meralgia paresthetica and radiculopathy of the left leg -A case report-

“…Usually, MP symptoms are typical and consistent, in which paresthesia is localized to LFCN and activities such as walking and descending the stair can aggravate the symptoms, because these activities require extension of the hip and stretching the nerve [6]. These symptoms result from entrapment or compression of the LFCN, which arises from the 2nd and 3rd spinal nerve of the lumbar plexus, and transits between the inguinal ligament and the ASIS [3]. It can develop primarily by increasing abdominal pressure caused by obesity, pregnancy, pelvic mass, tight clothes, metabolic disease and diabetes mellitus, or can be caused secondarily by surgical procedure or local trauma [7].…”

“…After detailed history taking and lateral femoral cutaneouse nerve block, he was diagnosed with MP. Meralgia paresthetica (MP) is a sensory mononeuropathy of the lateral femoral cutaneouse nerve (LFCN), which is commonly due to focal entrapment of this nerve as it passes through the inguinal ligament [1][2][3]. However, corresponding presentations in the same area of both MP and L4, L5…”

Ultrasound-Guided Interventional Procedures for Chronic Pain Management

“…Pain in this nerve distribution is called 'meralgia paresthetica' [72]. The nerve emerges from the psoas, travels laterally and caudally along the iliacus and emerges from under the inguinal ligament medial to the ASIS between the fascia lata and fascia iliaca [64].…”

“…The lateral femoral cutaneous nerve (LFCN) is a small nerve branch from the lumbar 2 and 3 future science group www.futuremedicine.com nerves that supplies sensory innervation for the anterolateral portion of the thigh [71,72]. Pain in this nerve distribution is called 'meralgia paresthetica' [72].…”

“…If not visualized at this level, the operator may scan below the inguinal ligament where it can be found in the plane above the sartorious muscle. An in plane or out of plane may be used to place the injectate adjacent to the nerve [64,72].…”