7 – Scanning technique

All five nerves innervating the ankle are blocked in an ankle block. Place the patient supine.

The probe is a high-frequency linear probe and all five nerves are scanned in short-axis view: – the deep peroneal nerve is blocked anterior to the ankle joint where it is adjacent to the dorsal pedis artery
– the superficial peroneal nerve is blocked approx. 10 cm proximal to the lateral malleolus where it emerges between the lateral and anterior compartments
– the tibial nerve is blocked posterior to the medial malleolus where it is adjacent to the posterior tibial artery
– the sural nerve is blocked posterior to the lateral malleolus where it is adjacent to the short saphenous vein
– the saphenous nerve is blocked anterior to the medial malleolus by infiltrating the subcutaneous tissue around the long saphenous vein

The target nerve and proxy arteries are visualized (see next pages) and the needle is inserted with in-plane technique. Inject approx. 3-4 mL perineurally around each target nerve