Meralgia Paraesthetica

Key points

• Meralgia paraesthetica comes from the Greek words meros for thigh and algos for pain and is often described as a syndrome of paraesthesia or anaesthesia in the distribution of the lateral femoral cutaneous nerve (LFCN).
• The LFCN is primarily a sensory nerve, carrying no motor fibres.
• It most commonly originates from the L2/3 segments.
• After passing behind the psoas muscle, it runs beneath the iliac fascia as it crosses the surface of the iliac muscle and eventually exits through or under the lateral aspect of the inguinal ligament.
• As the nerve curves medially and inferiorly around the anterior superior iliac spine (ASIS), it may be subject to repetitive trauma or pressure.