Furcal Nerve
The furcal nerve (forked nerve) links the lumbar plexus and the sacral plexus. It has its own dorsal and ventral branches with fibres that branch out to become part of the femoral and obturator nerves. The furcal nerve is found in the lumbosacral trunk most commonly at the level of the fourth lumbar vertebra (L4). Structure and location The furcal nerve is an independent nerve that links the lumbar plexus to the sacral plexus. It is most commonly found at the level of the fourth lumbar vertebra. The next most common site is the level of the third lumbar vertebra (L3). The furcal nerve can be found at any level from L1 to S1 but has not been reported at L1. Occasionally a double furcal nerve is found. It gives branches to the femoral nerve, lumbosacral trunk, and obturator nerve The obturator nerve in human anatomy arises from the ventral divisions of the second, third, and fourth lumbar nerves in the lumbar plexus; the branch from the third is the largest, while that from the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Lumbar Plexus
The lumbar plexus is a web of nerves (a nerve plexus) in the lumbar region of the body which forms part of the larger lumbosacral plexus. It is formed by the divisions of the first four lumbar nerves (L1–L4) and from contributions of the subcostal nerve (T12), which is the last thoracic nerve. Additionally, the ventral rami of the fourth lumbar nerve pass communicating branches, the lumbosacral trunk, to the sacral plexus. The nerves of the lumbar plexus pass in front of the hip joint and mainly support the anterior part of the thigh.''Thieme Atlas of anatomy'' (2006), pp 470-471 The plexus is formed lateral to the intervertebral foramina and passes through psoas major. Its smaller motor branches are distributed directly to psoas major, while the larger branches leave the muscle at various sites to run obliquely down through the pelvis to leave under the inguinal ligament with the exception of the obturator nerve which exits the pelvis through the obturator foramen. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Sacral Plexus
In human anatomy, the sacral plexus is a nerve plexus which provides motor and sensory nerves for the posterior thigh, most of the lower leg and foot, and part of the pelvis. It is part of the lumbosacral plexus and emerges from the lumbar vertebrae and sacral vertebrae (L4-S4).''Thieme Atlas of Anatomy'' (2006), pp 470-471 A sacral plexopathy is a disorder affecting the nerves of the sacral plexus, usually caused by trauma, nerve compression, vascular disease, or infection. Symptoms may include pain, loss of motor control, and sensory deficits. Structure The sacral plexus is formed by: * the lumbosacral trunk * the anterior division of the first sacral nerve * portions of the anterior divisions of the second and third sacral nerves The nerves forming the sacral plexus converge toward the lower part of the greater sciatic foramen, and unite to form a flattened band, from the anterior and posterior surfaces of which several branches arise. The band itself is continued as the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Femoral Nerve
The femoral nerve is a nerve in the thigh that supplies skin on the upper thigh and inner leg, and the muscles that extend the knee. It is the largest branch of the lumbar plexus. Structure The femoral nerve is the major nerve supplying the anterior compartment of the thigh. It is the largest branch of the lumbar plexus, and arises from the dorsal divisions of the ventral rami of the second, third, and fourth lumbar nerves (L2, L3, and L4). The nerve enters Scarpa's triangle by passing beneath the inguinal ligament, just lateral to the femoral artery. In the thigh, the nerve lies in a groove between iliacus muscle and psoas major muscle, outside the femoral sheath, and lateral to the femoral artery. After a short course of about 4 cm in the thigh, the nerve is divided into anterior and posterior divisions, separated by lateral femoral circumflex artery. The branches are shown below: Muscular branches * The nerve to the pectineus muscle arises immediately above the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Obturator Nerve
The obturator nerve in human anatomy arises from the ventral divisions of the second, third, and fourth lumbar nerves in the lumbar plexus; the branch from the third is the largest, while that from the second is often very small. Structure The obturator nerve originates from the anterior divisions of the L2, L3, and L4 spinal nerve roots. It descends through the fibers of the psoas major, and emerges from its medial border near the brim of the pelvis. It then passes behind the common iliac arteries, and on the lateral side of the internal iliac artery and vein, and runs along the lateral wall of the lesser pelvis, above and in front of the obturator vessels, to the upper part of the obturator foramen. Here it enters the thigh, through the obturator canal, and divides into an anterior and a posterior branch, which are separated at first by some of the fibers of the obturator externus, and lower down by the adductor brevis. An accessory obturator nerve may be present in ap ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Lumbosacral Trunk
The lumbosacral trunk is nervous tissue that connects the lumbar plexus with the sacral plexus. It is formed by the union of parts of the fourth and fifth lumbar nerves and descends to join the sacral plexus. Anatomy The lumbosacral trunk is formed by the union of the entire anterior ramus of lumbar nerve L5 . L4 first issues its branches to the lumbar plexus, then emerges from the medial border of the psoas muscle to unite with the anterior ramus of L5 just superior to the pelvic brim to form the thick, cord-like trunk which crosses the pelvic brim (medial to the obturator nerve) to descend upon the anterior surface of the ala of sacrum before joining the sacral plexus. Like the sacral nerves, the lumbosacral trunks splits into an anterior division and a posterior division before recombining to form nerves for the flexor and extensor compartments of the lower limb. Clinical significance The lumbosacral trunk may be compressed by the fetal head during the second stage of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Sciatica
Sciatica is pain going down the leg from the lower back. This pain may go down the back, outside, or front of the leg. Onset is often sudden following activities such as heavy lifting, though gradual onset may also occur. The pain is often described as shooting. Typically, symptoms are only on one side of the body. Certain causes, however, may result in pain on both sides. Lower back pain is sometimes present. Weakness or numbness may occur in various parts of the affected leg and foot. About 90% of sciatica is due to a spinal disc herniation pressing on one of the lumbar or sacral nerve roots. Spondylolisthesis, spinal stenosis, piriformis syndrome, pelvic tumors, and pregnancy are other possible causes of sciatica. The straight-leg-raising test is often helpful in diagnosis. The test is positive if, when the leg is raised while a person is lying on their back, pain shoots below the knee. In most cases medical imaging is not needed. However, imaging may be obtained if bo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |