Spinal nerve
The ventral ramus contains nerves that serve the remaining anterior parts of the trunk and the upper and lower limbs (hypaxial muscles) carrying visceral motor, somatic motor, and sensory information to and from the ventrolateral body surface, structures in the body wall, and the limbs.Branches also exit the spine and go directly to the paravertebral ganglia of the autonomic nervous system where they are involved in the functions of organs and glands in the head, neck, thorax and abdomen.The medial branches of the lower six are distributed chiefly to the multifidus and longissimus dorsi, occasionally they give off filaments to the skin near the middle line.The medial branches of the posterior divisions of the lumbar nerves run close to the articular processes of the vertebrae and end in the multifidus muscle.The upper three give off cutaneous nerves which pierce the aponeurosis of the latissimus dorsi at the lateral border of the erector spinae muscles, and descend across the posterior part of the iliac crest to the skin of the buttock, some of their twigs running as far as the level of the greater trochanter.These rami consist of long, slender branches which accompany the lumbar arteries around the sides of the vertebral bodies, beneath the psoas major.The nerves pass obliquely outward behind the psoas major, or between its fasciculi, distributing filaments to it and the quadratus lumborum.The first three and the greater part of the fourth are connected together in this situation by anastomotic loops, and form the lumbar plexus.The smaller part of the fourth joins with the fifth to form the lumbosacral trunk, which assists in the formation of the sacral plexus.[4][6] The sacral nerves have both afferent and efferent fibers, thus they are responsible for part of the sensory perception and the movements of the lower extremities of the human body.From the S2, S3 and S4 arise the pudendal nerve and parasympathetic fibers whose electrical potential supply the descending colon and rectum, urinary bladder and genital organs.
1. Somatic efferent .
2. Somatic afferent .
3,4,5. Sympathetic efferent .
6,7. Autonomic afferent .
Anatomical terms of neuroanatomymixed nervesensoryautonomicspinal cordhuman bodynervesvertebral columncervicalthoraciclumbarsacralcoccygealperipheral nervous systemnerve rootfibersdorsalventral rootsafferentefferentintervertebral foramenoccipital boneSomatic efferentSomatic afferentSympathetic efferentAutonomic afferentdorsal ramusepaxial musclesventral ramushypaxial musclesmeningeal branches (recurrent meningeal or sinuvertebral nerves)rami communicantesnerve plexusspinal plexusescervical plexusbrachial plexuslumbar plexussacral plexuscoccygeal plexussuboccipital nervegreater occipital nervethird occipital nervesternohyoidsternothyroidomohyoid musclesansa cervicalisthoracic vertebraparavertebral gangliaautonomic nervous systemintercostal nervesintercostobrachial nervesubcostal nervesemispinalis dorsimultifidusrhomboidtrapezius muscleslongissimus dorsilumbar nervesmultifidus muscleerector spinae muscleslatissimus dorsiiliac crestbuttockgreater trochantergray rami communicanteslumbar gangliasympathetic trunklumbar arteriespsoas majorgangliawhite ramus communicansfasciculiquadratus lumborumlumbosacral trunkfurcal nervesacrumL1 vertebracauda equinaanterior sacral foraminaposterior sacral foraminalumbosacral plexusefferent fiberssensory perceptiondescending colonrectumurinary bladdergenital organscentral nervous systemcoccyxanococcygeal nerveflexorsextensorsdiaphragmshoulderdeltoidbicepssupinateExtendtricepspronateIntercostalsAbdominalhip jointAdductquadriceps femorisabducthamstringsDorsiflextibialis anteriorgluteus maximusspinal plexusanterior nerve rootsmyotomedermatomesmuscle weaknesssacral nerve stimulationSciaticaPlexusCranial nervesNervous systemMeningesHindbrainMedullaCerebellumMidbrainForebrain