Lateral femoral cutaneous nerve

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Arteries, veins and nerves of the hip and thigh.

The lateral femoral cutaneous nerve originates from the dorsal branches of the second and third lumbar ventral rami. This nerve emerges from the lateral edge of the psoas major muscle and travels diagonally across the iliacus muscle. It then heads towards the anterior superior iliac spine. On its way, it provides innervation to the parietal peritoneum that is located in the iliac fossa. 

The right nerve courses in a posterolateral direction relative to the caecum. It is separated from the caecum by the iliac fascia and peritoneum.

The left nerve passes behind the lower section of the descending colon. Both left and right nerves travel either behind or through the inguinal ligament. They then pass anteriorly through or alongside the sartorius muscle into the thigh. Here they then further divide into anterior and posterior branches.

The anterior branch of the nerve becomes superficial a few centimeters below the anterior superior iliac spine. This branch then proceeds to provide innervation to the skin on the front and outer side of the thigh. This innervation extends all the way to the knee. At its endpoint, it connects with the cutaneous branches of the anterior division of the femoral nerve and the infrapatellar branch of the saphenous nerve. These branches then  combine to form the peripatellar plexus.

The posterior branch penetrates the fascia lata at a higher position compared to the anterior branch. It then splits to provide innervation to the skin on the outer side. This innervation extends from the greater trochanter to approximately the middle of the thigh. The posterior branch may also supply sensation to the skin of the gluteal region.