Category: Nervous System

Femoral Nerve Pathway Femoral Nerve Pathway The femoral nerve originates from the lumbar plexus and is the largest branch of this plexus. Below is its detailed pathway from origin to termination: Origin: Lumbar Plexus L2-L4 Formed by contributions from the ventral rami of L2, L3, and L4. Emerges from the lateral border of the psoas major muscle. Course in the Abdomen Travels inferiorly and laterally between the psoas major and iliacus muscles. Remains posterior to the iliac fascia. Passage Under the Inguinal Ligament Passes deep to the inguinal ligament in the iliac fossa. Enters the femoral triangle lateral to the Read More

Path of the Sciatic Nerve The sciatic nerve is the largest nerve in the human body, originating from the lumbosacral plexus and extending down the posterior aspect of the lower limb before dividing into its terminal branches. Here’s a detailed description of its path: 1. Origin The sciatic nerve arises from the lumbosacral plexus, specifically from the ventral rami of L4, L5, S1, S2, and S3. These nerve roots contribute to two major divisions: Tibial division (L4-S3) Common fibular (peroneal) division (L4-S2) 2. Pelvic Course The nerve exits the pelvis through the greater sciatic foramen, passing inferior to the piriformis Read More

1. Origin in the Brainstem Nuclei: The vagus nerve fibers arise primarily from two major nuclei in the medulla oblongata: Dorsal motor nucleus of the vagus (parasympathetic component) Nucleus ambiguus (motor fibers to certain skeletal muscles, e.g., pharynx and larynx) Sensory information projects into the solitary nucleus (especially visceral and taste sensation). Emergence from the Medulla: The vagus nerve exits the medulla on its lateral aspect, in the region between the olive and the inferior cerebellar peduncle. It exits the skull via the jugular foramen alongside the glossopharyngeal nerve (CN IX) and the accessory nerve (CN XI). 2. Ganglia Near Read More