The lumbosacral plexus is a network of nerves located in the lower back, formed by the lumbar and sacral spinal nerves. It primarily supplies motor and sensory functions to the lower limbs and pelvic region. The plexus is crucial for movements such as walking and running, as well as for sensations in the legs and feet. Key nerves that arise from the lumbosacral plexus include the femoral nerve, which innervates the front of the thigh, and the sciatic nerve, the largest nerve in the body, which runs down the back of the leg. This complex system ensures coordinated movement and sensation in the lower body.