Lec 18 Peripheral Nerve Injuries Flashcards
Explain dermatome patterns - front of leg
starting at inner thigh L1, then L2 moving laterally then L3, L4 makes it down to shin and medial malleolus, L5 comes from back side and wraps around at knee and cover dorsum of foot, S1 is pinky tow and lateral malleolus
KNOW PERIPHERAL INNERVATION OF THE LOWER LEG AND FOOT
KNOW PARENT STRUCTURES
Describe dermatomes back of leg
L5 upper lateral thigh/glute wraps around to front before the knee
moving in is S1, from top to bottom, S2,
bottom of foot is S2 and L5 (wrapped over toes from dorsum)
Name the peripheral nerves in the inguinal region and their general location
Genitofemoral nerve
Ilioinguinal nerve
From lateral to medial its femoral branch, ilioinguinal, genital branch
Peripheral sensory location of Obturator Nerve
upper medial thigh
remember sural =
saphenous =
sural = lateral
saph = medial
Peripheral sensory location of lateral cutaneous nerve
what’s its parent structure?
lateral thigh
from lumbar plexus L2 L3
describe the peripheral nerve map of the leg
femoral front of thigh
obturator upper medial thigh
lateral cutaneous femoral nerve on lateral thigh (not a branch of femoral!)
posterior cutaneous nerve on back of thigh past knee
femoral nerve saphenous branch on medial lower leg
common fibular lateral cutaneous on upper half of lateral leg
common fibular superficial on lower half of lateral lower leg and dorsum of foot
tibial nerve sural branch on lateral ankle and 5th toe
Femoral nerve peripheral sensory location
anterior thigh (anterior cutaneous nerve)
describe the peripheral nerves of the foot and their location (list their parent structure)
saphenous nerve (femoral) medial ankle
common fibular nerve superficial branch (common fibular nerve, then sciatic) on lateral ankle and dorsum of foot
lateral cutaneous nerve of foot (sural nerve)
dorsal digital nerve (from deep fibular nerve) between toe 1 and 2
medial plantar nerve (tibial nerve) on medial plantar side, toes 1-4.5, wraps around to toes on dorsal side (like the palm)
lateral plantat nerve (tibial nerve) on lateral plantar surace, toes 4.5-5
medial calcaneal branch (tibial nerve) on heel
Saphenous nerve Peripheral sensory location
What is its parent structure?
Medial lower leg
Femoral nerve branch
Common fibular nerve (lateral cutaneous) Peripheral sensory location
What is its parent structure?
superior half of lateral lower leg and lateral calf
Common fibular nerve
Peripheral sensory location of common fibular nerve (superficial branch)
inferior half of lateral lower leg and dorsum of foot
Peripheral sensory location of common fibular nerve (deep branch)
in between 1st and 2nd toe
Tibial nerve (sural) and (medial calcaneal branches) Peripheral sensory location
sural - lateral edge of foot and back of lateral ankle
medial calcaneal - back of heel
Peripheral nerves on the plantar surface of the foot
medial plantar nerve and lateral plantar nerve
Posterior cutaneous nerve of thigh Peripheral sensory location
posterior end of glute down just passed knee
so the entire plantar surface is supplied with peripheral nerves from what parent nerve?
tibial nerve
Who is the main hip medial rotator?
TFL!
What are causes of sciatica?
Herniated NP
Spondylosis
Spondylolysis/Spondylolisthesis
Spinal stenosis
Osteophytes
Piriformis
Hamstring strain
the piriformis divides the greater sciatic foramen into …
superior and inferior portions
What nerves are names based on their location relative to piriformis?
superior gluteal nerve
inferior gluteal nerve
tibial nerve course
The tibial nerve runs down the posterior thigh and posterior calf innervating muscles there before splitting into the medial and lateral plantar nerves at the ankle, which then provide sensory and motor innervation to the foot
common fibular nerve course
The common fibular nerve travels laterally around the fibular head (near the knee), then divides into its two terminal branches.
The deep fibular nerve innervates the anterior compartment of the leg (muscles that dorsiflex the foot, such as tibialis anterior).
The superficial fibular nerve innervates the lateral compartment of the leg (fibularis longus and brevis muscles).
How is Piriformis Syndrome caused? What will it affect?
portion of the sciatic nerve can pierce the piriformis or the piriformis can become chronically tight/spasms especially in women and cyclist
Will affect ROM (hip internal rot)
What would increase sciatic pain in piriformis syndrome? In what direction do you stretch it to relieve symptoms?
muscle contraction would compress the nerve causing symptoms
stretch in opposite direction of its main action - so do hip internal rotation (with extended hip) and adduction with flexed hip (?)
The sciatic nerve runs down the entire…
posterior leg, entire foot, entire anterior lower leg
think about these areas if the sciatic nerve was injured