Lumbosacral Plexus and Blood to the Lower Limbs Flashcards
Lumbar plexus
L1-L4
Limb muscles develop from which two myotomic cel groups? What do those two groups develop into?
Dorsal muscle mass (extensors)
Ventral muscle mass (flexors)
Which nerve provides supplies cutaneous innervation to the lateral part of the thigh? Which fibers make up this nerve?
Lateral femoral nerve (L2-L3)
Which nerve(s) delevop from the posterior diviision of the lumbar plexus?
lateral femoral cutaneous nerve
femoral nerve
This nerve provides motor innervation to the anterior part of the thigh as well as cutaneous branches that go to the skin that covers those muscles
Femoral nerve
This nerve provides motor innervation to the anterior muscle mass and arises from the anterior dicition of the lumbar plexus
Obturator nerve
The posterior compartment of the thigh is innervated by the __________ nerve.
Sciatic
The ___________ division of the lumbar plexus innervates the anterior compartment of the thigh and the ___________ division of the lumbar plexus innervates the medial compartment of the thigh.
Posterior; anterior
The femoral nerve enters the thigh by passing deep to the _____________ ligament entering the femoral triangle.
Inguinal
The obturator nerve goes into the pelvis and travels through the obturator foramen to get to the _________ part of the thigh.
Medial
What is the lumbosacral trunk?
It is a communication/contribution tot he sacral plexus from the lumbar plexus. It makes up part of L4 and all of L5.
What nerves arise from the sacral plexus? What fibers contribute to these nerves?
Posterior
Superior gluteal (L4, L5, S1)
Inferior gluteal (L5, S1, S2)
Nerve to piriformis (S1, S2)
Common fibular (L4, L5, S1, S2)
Anterior
Tibial nerve ((L4, L5, S1, S2, S3)
Nerve to obturator (L5)
Nerve to quadratus femoris (L4)
The common fibular nerve comes off the ___________ division.
Posterior
The tibial nerve comes off the ___________ division.
Anterior
Do the two divisions of the sciatic nerve ever mix?
No they never mix, they remain separate
Where does the sciatic nerve divide into the common fibular and tibial nerves?
in the popliteal fossa
The ____________ nerve remains in the middle of the popliteal fossa and the ____________ nerve shifts laterally.
Tibial nerve; common fibular
As the common fibular nerve crosses the neck of the fibula it becomes….
Deep fibular
Superficial fibular
What compartements do the two divison of the common fibular nerve innervate?
Deep fibular nerve
- Innervates: Anterior compartment of the leg
Superficial fibular nerve
- Inenrvates: Lateral compartment of the leg
The ___________ nerve innervates the posterior compartment of the leg.
Tibial nerve
Does the tibial nerve run with the tibial artery?
Yes
After crossing behing the _________, the tibial enrve terminates as which to nerves?
Medial malleolus
Medial plantar nerve; Lateral plantar nerve
What compartment does the medial plantar nerve innervate?
The medial compartment of the foot
What compartment does the lateral plantar nerve innervate?
Lateral, interosseous and central compartments of the foot
*In the central compartment, the flexor digitorum brevis and the 1st lumbrical are innervated by the medial plantar nerves
The anterior femoral nerve terminates as which nerve? What does this nerve innervate?
The anterial femoral nerve terminates as the saphenous nerve (cutaneous). The saphenous nerve supplies the medial part of the leg, both anterior and posterior parts of medial
*Note: At this stage, the saphenous nerve is barely sensory. It is called saphenous because it runs with the saphenous vein.