TEST 2 - lower extremity stuff Flashcards
sciatic n. block root levels & landmarks and technique for needle insertion
L4-S3, lateral sims, draw line b/t posterior superior iliac spine and greater trochanter; at the midpoint, draw perpendicular to this line ~5cm caudomedially for needle insertion point
As sciatic n. moves distal from cords, what two branches/nerves jump off?
tibial n. and peroneal n.
At the needle insertion site for the sciatic n. what muscle does it lie posterior to?
piriformis
femoral n. block root levels & position, landmarks and technique for needle insertion
L2-L4, supine, draw line b/t ant. superior iliac spine and pubic tubercle, palpate fem. artery, just lateral to FA is needle insertion point
NAVEL stands for>
nerve, artery, vein, empty space, lymphatics
At the needle insertion site for the femoral n. what ligament does it lie posterior to?
inguinal
sciatic n. motor innervation (of the foot) indicated by?
plantar flexion of the foot (posterior tibial nerve) or dorsiflexion of the foot (common perineal nerve)
femoral n. motor innervation indicated by?
twitching of quadriceps
obturator n. motor innervation indicated by?
Obturator – twitching of adductor muscles on the medial side of the leg.
lateral femoral cutaneous n. motor innervation indicated by?
Lateral femoral cutaneous – none
obturator n. block root levels & position, landmarks and technique for needle insertion
L2-L4, 1.5 cm lateral to pubic tubercle, 1.5 cm inferior for needle insertion point
obturator n. passes through what part of pelvis?
obturator foramen
lumbar plexus n. block root levels & position, landmarks and technique for needle insertion
L1-L4, lateral decubitus, draw line b/t iliac crest, spinous processes (MIDLINE), 4cm lateral to spinous process is needle insertion point
lumbar plexus covers what (AKA 3 in 1)
A lumbar plexus block provides anesthesia for the anterolateral and medial thigh, knee, and the saphenous nerve below the knee (lateral femoral cutaneous, obturator & femoral nerves). When combined with a sciatic nerve block, anesthesia of the entire leg can be achieved.
lumbar plexus motor innervation is indicated by what?
quadriceps twitching
name 5 nerves involved in foot block
saphenous, sural, tibial (posterior/deep) and superficial and deep peroneal n.
nerves of the foot are branches of which 3 major nerves?
SCIATIC - TIBIAL, sural, COMMON PERONEAL - deep peroneal, superficial peroneal
FEMORAL - saphenous is the terminal branch
what block provides anesthesia/analgesia to anterior thigh and knee?
femoral block
what block is best for ACL repair?
femoral as adjunct to GA for KNEE region
what nerves provide coverage ABOVE the knee?
femoral, sciatic, lat. femoral cut., and obturator
what is the “3 in 1” block, WHAT nerves does it cover.
LUMBAR PLEXUS, lateral femoral cutaneous, obturator & femoral nerves
terminal branch of femoral n.?
saphenous
what n. blocks lower leg and foot?
sciatic
of 5 nerves in foot, which 3 are superficial
superficial peroneal, saphenous, sural AKA “Tres S’s”
which n. in foot does not arise from sciatic n.?
saphenous (FEMORAL)
sural n. is branch of
TIBIAL (SCIATIC)
THE FIVE NERVES of the foot have what function? WHICH DO FLEXION/EXTENSION?
sural - lateral sensation
tibial - sensation of heel, medial/lateral sole
sup. peroneal - sensation to dorsum & toes
deep peroneal - medial half & dorsum & toe extension
saphenous - superficial sensation anteromedial foot
TIBIAL - FLEXION, EXTENSION - PERONEAL
SURAL n. is blocked b/t which structures
lat. malleolus & Achilles tendon
general C.I. for lower extremity blocks
Infection at the injection site
Anticoagulant therapy
persistent peripheral neuropathies and/or paresthesias
High risk of developing compartment syndrome post-operatively
Surgical intervention on lower extremity nerves (i.e. need for neuromonitoring like SSEP, MEP, EMG, etc.)
which lower extremity block has highest risk for systemic toxicity and why
lumbar pleuxus d/t placement deep in muscle beds, place w/ appropriate training only
sciatic n. blocks best for which type of procedures?
knees and other lower leg, ankle or tibial fractures, and for patients in whom it may be desirable to avoid the sympathectomy accompanying neuraxial block, sciatic block combined with femoral nerve block often allows ankle and foot procedures to be carried out.
obturator n. blocks best for which type of procedures
medial thigh and combined w/ others it is best for KNEES
femoral n. block best for which type of procedures
anterior thigh, knee, femur, and combined w/ other regional technique/therapies for lower legs, and femoral fractures
lateral cutaneous n. block best for which procedures/anatomical location?
lateral thigh
