Download Ankle block MGMC

Ankle block
Dr. S. Parthasarathy
• MD., DA., DNB, MD (Acu), Dip. Diab. DCA,
Dip. Software statistics
• PhD (physio)
• Mahatma Gandhi Medical college and
research institute , puducherry India
Indication
• Anaesthesia and postoperative analgesia of
the foot.
• Patient Selection
• The ankle block is principally an infiltration
block and does not require elicitation of
paraesthesia. Thus, patient cooperation is not
mandatory.
Anatomic Landmarks
• Five nerves supply the foot,
• four of which derive from the sciatic nerve
(the tibial, the superficial and deep peroneal,
the sural nerves) and
• one from the femoral nerve (the saphenous
nerve).
Anatomy of ankle nerves
Posterior tibial nerve
Cross section
Area of innervations
Technique
• Generally, infiltration techniques are used for
ankle blocks
• The posterior tibial nerve can be blocked by a
nerve stimulator technique.
• All blocks are performed at the upper levels
of the malleoli.
• patients should be adequately sedated during
this block because it is primarily a “volume”
block.
Patient Position
• The patient lies supine in neutral position or
slight internal and then external rotation
according to the nerve to be blocked
Pillow to raise
SAPHENOUS NERVE BLOCK
• The saphenous nerve runs in the superficial fascia in
front of the medial malleolus accompanying the
saphenous vein and innervates the medial side of the
foot.
• Technique
• For saphenous nerve block, 3 to 5 mL of local
anesthetic is injected subcutaneously on either side
of the saphenous vein at the superior aspect of the
medial malleolus
Saphenous N block
TIBIAL NERVE BLOCK
• The tibial nerve lies under the flexor
retinaculum at the midpoint between the
medial malleolus and calcaneus
• A point is marked midway between the medial
malleolus and calcaneus. If the posterior tibial
artery is palpated, the needle is inserted just
posterior to the pulse, following which 3–5 mL
of local anesthetic is injected.
TIBIAL NERVE BLOCK
• Conversely, a 25-mm stimulating needle can
be inserted at the skin mark and directed
posterior to the tibial arterial pulse, looking
• for plantarflexion of the toes.
Tibial and sural nerves
The sural nerve
• located superficially between the lateral
malleolus and the Achilles tendon. A 25gauge, 3-cm needle is inserted lateral to the
tendon and directed toward the malleolus as
5 to 10 mL of solution is injected
subcutaneously
Peroneal nerves
DEEP PERONEAL NERVE BLOCK
• A needle is inserted perpendicular to skin just
lateral to the extensor hallucis longus tendon
to contact the tibia. It is then withdrawn a few
millimeters and 3 mL of local anesthetic is
injected.
SUPERFICIAL PERONEAL NERVE BLOCK
• Subcutaneous infiltration of 5 to 7 mL of local
anaesthetic from the lateral to the medial
malleolus.
Drugs
• motor blockade is not often needed, pt. can
walk with analgesia
• Lower concentrations of local anesthetics may
be used.
• Practical choices are 1% lidocaine, 1%
mepivacaine, 0.25% to 0.5% bupivacaine, and
0.2% to 0.5% ropivacaine.
• Epinephrine ???, especially if injection is
circumferential.
Anatomy and USG
Local injected
Deep peroneal nerve
Sural nerve
Complications
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Induration may cause difficulty
Partial anaesthesia
Pain with mutiple injections
Infection
Haematoma
Nerve injury
Summary - ankle block
Anaesthesia analgesia of foot
Five nerves , 4 sciatic and one femoral
Tibial, deep and sup. Peroneal, sural
Saphenous
Tibial and deep peroneal deeper (USG)
Others superficial (normal technique)
Technique
Complications
We should know all blocks because we
may need to anaesthetize such people
Thank you all