Manual 69-71: Nerves of Thigh Flashcards
roots femoral branch of genitofemoral n
L1-2
the femoral branch of genitofemoral n passes ______ to the genital branch
lateral
the femoral branch of genitofermoral n travels with …
- external iliac/femoral a deep to the inguinal ligament in the lateral compartment of the femoral sheath
- lays on top of psoas major
femoral branch of genitofemoral n supplies…
skin on proximal, anterior surface of thigh
roots lateral femoral cutaneous n
L2-3
how does the lateral femoral cutaneous n travel
- first appears over lateral border of psoas major
- passes over iliacus toward ASIS and goes under inguinal ligament
- goes over the sartorius m
which branch of the lateral femoral cutaneous n supplies skin over lateral and anterior thigh?
- anterior branch
- posterior branch supplies skin of lateral thigh (greater trochanter to mid-thigh)
roots obturator n
L2-4
how does the obturator n enter the thigh?
- into medial compartment of thigh through obturator canal
which branch of the obturator n is more superficial
anterior brnach
where is the anterior branch of obturator n located in relation to muscles
- anterior to adductor brevis
- passes over the obturator externus
- deep to pectineus and adductor longus
- superficial to adductor brevis
what branches come off the anterior branch of obturator n.?
- communication with accessory obturator if present
- articular branch to hip joint
- muscular branches to adductor longus, gracilis, adductor brevis, rarely pectineus
- cutaneous branches to akin on medial thigh just above knee
where is the posterior branch of obturator n located in relation to muscles
- posterior to adductor brevis
- anterior to adductor magnus
which branch of the obturator n give an articular branch to knee joint
posterior/deep branch
- anterior gives branch to hip joint
which m does the posterior branch of obturator n supplly
- obturator externus (goes through it)
- adductor magnus
- adductor brevis sometimes
how often is the accessory obturator n present
10%
roots accessory obturator
L3-4
what does the accesssory obturator supply if present
- passes deep to pectineus and supplys muscular branches to it
- articular branch to hip joint
roots femoral n.
L2-4
is the femoral n in the femoral sheath
NO
- passes under inguinal ligament lateral to femoral a and lies OUtSIDE the femoral sheath
immediately after entering the thigh the femoral n divides into…
cutaneous and muscular branches
the anterior femoral cutaneous off of the femoral n divides into..
medial femoral cutaneous = skin of medial thigh distally to leg
intermediate femoral cutaneous branch = skin of anteiror thigh
what m are supplied by femoral n.
all muscles of anterior compartment (sartorius, quadratus femorus, articularis genu)
sometimes pectineus
longest branch of femoral n
saphenous n
how does the femoral n travel
- enters adductor canal with femoral a
- crosses lateral to medial in canal over the a
- leaves canal and passes to medial side of knee
does the femoral n pass through the adductor hiatus
NO
passes between tendons of sartorius and gracilis musclesa and runs down leg with great saphenous v
at the proximal 1/3 of the leg the saphenous n divides into
- subsartorial n plexus contribution
- infrapatellar branch (cutaneous innervation to skin over patella)
at the distal 1/3 of leg the saphenous n divides into terminal branches which …
supply skin at anterior and medial side of leg and foot as far as the ball of the foot
what forms the subsartorial n plexus
- communications from anterior branch of obturator, spahenous n, and medial femoral cutaneous n
where is the subsartorial n plexus located
- inferior margin of adductor longus
- deep to sartorius m
largest branch of sacral plexus
sciatic n
also the largest n in body
roots sciatic n
L4-S3
anterior division of all, posterior divisions up to S2
what does the sciatic n supply
- posterior compartment muscles
- ALL muscles of leg and foot
- skin of foot
- most of the skin of leg
- ALL joints of lower extremity
how many nerves comprise the sciatic n
anatomically one nerve, physiologically two nerves wrapped together in single connective tissue sheath
- both nerves have separate origins from sacral plexus. fibers do not mix while traveling together
when does the sciatic n split into tibial and common peroneal n
split as passes into distal 1/3 of posterior thigh (emerging from beneath long head of biceps femoris)
roots tibial n
anterior division L4-S3
roots common peoneal n
posterior divisions L4-S2
before it splits the sciatic n gives off what branches
- articular branches to hip joint
- muscular branches to hamstrings (tibial- all posterior compartment m of thigh - and common peroenal portion - short head biceps femoris)
the posterior compartment muscles of thigh are supplied by what?
tibial portion of sciatic n EXCEPT for the short head of biceps femoris which is innervated by common peroneal poriton
if the sciatic n divides early, which part leaves pelvis inferior to piriformis
tibial n
common peroneal n will pierce piriformis
the posterior cutaneous n may arise in two parts …
- ventral part accompanying the tibial n and giving rise to peroneal n and medial cutaneous n
- dorsal branch passing through piriformis with common peroneal n giving a gluteal branch and femoral branch
what n might peirce sacrotuberous ligament
inferior pudendal branch
how often is the perforating cutaneous n missing
1/3 to 1/2 bodies
- may arise in common with pudendal n
