Posterior part of lumbar plexus

The posterior part of lumbar plexus is formed by the dorsal divisions of the anterior rami of lumbar spinal nerves L2–L4. The lumbar plexus originates from the anterior rami of L1–L3 spinal nerves, along with a contribution from the anterior ramus of L4. Out of these, the anterior rami of the L2–L4 nerves each divide into ventral and dorsal divisions. Together, these dorsal divisions of the anterior rami of L2–L4 nerves constitute the posterior part of lumbar plexus.

Two major nerve branches which arise from the posterior part of lumbar plexus, include the femoral nerve and the lateral femoral cutaneous nerve of thigh.