Ankle Block

Chapter 6 Ankle Block



Overview



1. The following five nerves are involved in an ankle block: posterior tibial, superficial peroneal, deep peroneal, saphenous, and sural.

2. The posterior tibial and deep peroneal nerves are deep to the fascia, whereas the remainder of the nerves are superficial.


Indications for use



1. Foot fracture reduction

2. Soft tissue injuries about the foot


Precautions



1. Avoid intravascular and intraneural injections.

2. Do not use an ankle block for fractures of the ankle.


Pearls



1. The posterior tibial and deep peroneal nerve blocks should be performed first, because these nerves are deep to the fascia. Attempting to block the superficial nerves first will result in subcutaneous injection of anesthetic that may distort local anatomy.

2. The superficial nerves require only a subcutaneous injection of anesthetic.


Equipment



1. Antiseptic: Chlorhexidine prep stick or alcohol-soaked gauze

2. Syringe: Three 10-mL syringes

3. Needle:
a. Large-bore, blunt-tipped, drawing-up needle

b. 1½-inch, 25-gauge needle

4. Anesthetic:
a. Lidocaine: 15 mL of 2%

b. Bupivacaine: 15 mL of 0.5%

5. Sterile gloves

6. 4 × 4 inch gauze


Basic technique



1. Patient positioning:
a. The patient is supine.

b. The leg should be positioned either on a footrest or off the edge of the bed.

c. The posterior aspect of the ankle must be accessible.

2. Landmarks:
a. Posterior tibial nerve:
(1) Medial malleolus

(2) Posterior tibial artery (the nerve is posterior to this)

b. Deep peroneal nerve:
(1) Medial and lateral malleoli (the line connecting the two malleoli is the intermalleolar line)

(2) Extensor hallucis longus (EHL) tendon

(3) Extensor digitorum longus (EDL) tendon

(4) Anterior tibial artery (dorsalis pedis) (the nerve is immediately lateral to the artery)

c. Superficial peroneal nerve: Lateral malleolus

d. Saphenous nerve: Medial malleolus

e. Sural nerve:
(1) Lateral malleolus

(2) Lateral border of Achilles tendon

(3) Calcaneus

3. Steps:
a. Block the posterior tibial nerve.

b. Block the deep peroneal nerve.

Related posts:

Intra-articular Ankle Block Digital Block Femoral Skeletal Traction Basic Principles of Reduction Maneuvers Lower Extremity Splints and Casts Upper Extremity Splints and Casts

Stay updated, free articles. Join our Telegram channel
Tags:
Aug 24, 2016 | Posted by in ORTHOPEDIC | Comments Off on Ankle Block

Full access? Get Clinical Tree
Get Clinical Tree app for offline access