Närvipõimikud

Närvipõimikud, known in English as nerve plexuses, are intricate networks of nerves formed by the branching and recombination of anterior rami of spinal nerves. These structures play a crucial role in the peripheral nervous system, organizing and directing nerve impulses to specific areas of the body. Instead of individual spinal nerves directly innervating muscles or skin, the fibers from several spinal nerves intermingle within a plexus, creating a new set of nerves with fibers originating from multiple spinal nerve roots.

The formation of nerve plexuses allows for a more efficient and coordinated distribution of motor and sensory information. If a single spinal nerve is damaged, the function of the muscles or skin it innervates may not be completely lost because those areas receive input from other spinal nerves that have contributed fibers to the same plexus. This redundancy provides a degree of protection against localized nerve injury.

There are five major nerve plexuses in the human body: the cervical plexus, the brachial plexus, the lumbar plexus, the sacral plexus, and the coccygeal plexus. The cervical plexus, located in the neck, innervates muscles and skin of the neck, shoulders, and diaphragm. The brachial plexus, found in the shoulder region, is responsible for the innervation of the entire upper limb, including the arm, forearm, and hand. The lumbar plexus, situated in the lower back, serves the anterior and medial parts of the thigh. The sacral plexus, located posterior to the lumbar plexus, innervates the posterior thigh, leg, and foot, as well as pelvic structures. The coccygeal plexus is a small network of nerves in the region of the coccyx. Understanding these plexuses is fundamental to diagnosing and treating conditions affecting the peripheral nervous system.