Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
The lumbar plexus is a network of nerve fibers located in the lower back, arising from the spinal nerves L1 to L4. It provides motor and sensory innervation to the lower abdomen, parts of the thigh, and the hip area.
Each of these is part of a pair that emerges directly from the spine, providing pathways for neural signals to and from the brain to specific body regions.
Motor Innervation: This is the process by which nerve fibers transmit signals to muscles, enabling movement.
Sensory Innervation: This refers to how nerve fibers carry information about sensations (like touch, temperature, pain) from different body parts back to the brain