At L2 rami split into anterior and posterior divisions
How many segments does the lumbosacral plexus involve?
ventral rami of spinal nerves L1-S4
What does the lumbar plexus supply innervation to?
Muscles and skin of the anterior and medial thigh and skin of medial leg and foot.
What do anterior fibers correlate with?
anterior goes with pre axial *L1 is anterior division nerve
arises from L1 (sometimes T12) passes inferiorly and laterally across quadratus lumborum (extends and laterally flexes vertebral column) then the nerve innervates abdominal musculature and supplies skin of suprapubic region and upper gluteal
arises from L1. Also supplies abdominal muscles. It transverses inguinal canal and emerges through superficial inguinal ring. Cutaneous branches to upper medial thigh and anterior scrotum or labia majus.
L1, L2 emerges on anterior surface of psoas major and divides into genital and femoral branches. Genital branch goes to cremaster muscle and cutaneous areas of scrotum/ labia major and adjacent thigh. Femoral branch goes to skin over femoral triangle.
obturator nerve L2, L3, L4
emerges from medial border of psoas, passes through obturator canal and dividies into anterior and posterior (at adductor brevis muscle). Anterior branch goes to add long, brev and gracilis and sensory at hip. Posterior does obturator ex., add mag
What do posterior fibers correlate with?
posterior goes with post axial which involves muscles attaching to
Lateral femoral cutaneous
passes inferolaterally across iliacus muscle toward ASIS and enters thigh inferior to inguinal lig.
Supplies skin over lateral thigh and buttock
L2,L3,L4 largest branch of lumbar plexus; posterior division
Supplies iliacus and psoas major muscles then enters anterior thigh in femoral triangle. Innervates anterior thigh muscles. intermediate and medial femoral cutaneous n supply skin.
accompanies femoral vessels in the adductor canal and supplies skin on anterior and medial knee, leg and foot
joining of the remaining fibers of L4 and L5 NOT consibered part of lumbar plexus
meerges from medial border of psoas major to join sacral plexus
involves ventral rami of L4, L5 (lumbosacral trunk) and S1-4
this plexus is on the posterior pelvic wall, anteiror to the piriformis and deep to the pelvic fasica and perineum
supplies muscles and skin of gluteal region, post thigh, leg, and foot
L4, L5, S1, S2, S3 a and p divisions.
Largest nerve composed of tibial and common fibular which split at popliteal fossa
doesn't actually supply anything
L4, L5, S1, S2, S3 supplies articular branch to hip and knee. Supplies posterior thigh, posterior leg and sole of foot
Nerve to quadratus femoris and inferior gemmellus
L4, L5, S1 passes through greater sciatic foramen and gives articular branch to hip joint. supplies muscles in name
Nerve to obturator internus and superior gemmellus
L5. S1, S2
passes through the greater sciatic foramen and supplies muscles in name
posterior femoral cutaneous nerve
formed from anterior S2 and S3 and posterior S1 and S2
passes through the sciatic foramen w/ sciatic nerve and supplies inferior buttock, posterior scrotum/ labia majus and posterior thigh and knee
WILL BE TAGGED ON OUR BODY PROBABLY**
S2, S3, S4 passes through greater sciatic foramen, crosses sacrospinous ligament and reenters pelvis through lesser sciatic foramen
innervates external anal sphincter and urogenital triangle muscles and skin there
nerve to levator ani and coccygeus
S3 S4 supplies these muscles
Common fibular/ peroneal nerve
L4-5, S1-2 posterior division
Supplies short head of biceps femoris and articular branches to knee
passes over head of fibula, divides into superficial (lateral leg musc, skin on dorsum of foot) and deep (anterior leg musc and skin, dorsum of foot musc)
Superior gluteal nerve
L4, L5, S1 posterior division passes through greater sciatic foramen SUPERIOR to piriformis and supplies glut med, min, and TFL
articular branch to hip joint
Inferior Gluteal Nerve
L5, S1, S2 posterior division pass through greater sciatic foramen superior to piriformis and supplies glut max
Nerve to Piriformis
S1, S2 Passes through greater sciatic foramen to supply piriformis
ventral ramus of 5th sacral nerve and coccygeal nerve form this small plexus NOT PART OF SACRAL PLEXUS
forms anococcygeal nerve and supplies small area of skin over coccyx
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