Lower extremity blocks 3 (new) Flashcards
Match each nerve block with the region that it anesthetizes:
deep peroneal nerve
superficial peroneal nerve
sural nerve
tibial nerve
heel dorsum of foot
lateral aspect of foot
web space between 1st and 2nd toe
Deep peroneal nerve- web space between 1st and 2nd toe
tibial nerve- heel
superficial peroneal nerve- dorsum of foot
sural nerve- lateral aspect of foot
The foot and ankle are innervated by 5 nerves:
saphenous nerve
sural nerve
superficial peroneal nerve
deep peroneal nerve
posterior tibial nerve
What nerves of the foot and ankle are purely sensory nerves?
the three nerves that begin with an ‘S’
saphenous nerve
sural nerve
superficial peroneal nerve
Where do the nerves of the foot and ankle arise from?
all of them arise from the sciatic nerve, except for the saphenous nerve which arises from the femoral nerve
Which nerves contribute to inversion/eversion?
TIPPED
tibial inversion plantar flexion + peroneal eversion dorsiflexion
The saphenous nerve innervates the
medial aspect of the ankle and foot
The sural nerve innervates the
posterior portion of the heel
lateral sole of the foot
Achilles tendon above the ankle
The superficial peroneal nerve innervates the
dorsum of the foot
The deep peroneal nerve innervates the
lateral side of the great toe
medial side of the second digit
The posterior tibial nerve innervates the
sole of the foot
In the foot, the posterior tibial nerve divides into the
medial calcaneal
lateral plantar
& medial plantar nerves
Injecting a ring of local anesthetic from the midpoint of the distal tibia toward the inferior border of the medial malleolus will most likely anesthetize the:
a. sural nerve
b. posterior tibial nerve
c. saphenous nerve
d. superficial peroneal nerve
c. saphenous nerve
Indications for an ankle block include
foot surery
Complications of an ankle block include
nerve compression/ischemia
hematoma
LAST
To minimize the risk of nerve compression and ischemia, you should avoid
excessive volumes of local anesthetic or vasoconstrictors such as epinephrine
Which nerve is not immediately adjacent to a vascular structure (reducing the potential of bleeding, hematoma, & LAST)
superficial peroneal nerve
Describe the landmark technique to anesthetize the posterior tibial nerve.
Draw a line connecting the superior portion of the medial malleolus and the Achilles tendon
palpate the posterior tibial artery
insert needle perpendicular to the skin, posterior to the tibial artery
if the patient experiences paresthesia, inject and slowly withdraw
if there’s no paresthesia, advance until it contacts the medial malleolus and then withdraw 2-3 mm
Describe the landmark technique to anesthetize the sural nerve.
draw a horizontal line from the superior aspect of the lateral malleolus to the Achilles tendon
insert the needle in the plane of the line between the Achilles tendon and the lateral malleolus
You can block the following nerves without removing the needle:
deep peroneal
superficial peroneal
saphenous nerve
Describe the landmark technique to anesthetize the deep peroneal nerve.
With the patient in the supine position, draw a line from the superior border of the medial malleolus to the superior border of the lateral malleolus across the anterior aspect of the ankle
ask the patient to dorsiflex the foot
insert the needle perpendicular to the skin at the midpoint between the anterior tibial muscle and long muscles of the great toe
advance until you elicit paresthesia
Describe the landmark technique to anesthetize the superficial peroneal nerve.
block the deep peroneal nerve and then redirect the needle tip toward the inferior border of the lateral malleolus in the subcutaneous tissue and block the superficial peroneal nerve
Describe the landmark technique to anesthetize the saphenous nerve.
after blocking the deep peroneal and superficial peroneal nerves return to the midpoint and redirect the needle to the inferior border of the medial malleolus
find the saphenous nerve in the subcutaneous tissue adjacent to the saphenous vein and inject