Ultrasound-guided distal sciatic nerve block


Here too, as already described with regard to proximal subgluteal sciatic nerve blocks, the patient‘s lower leg is kept elevated for this distal nerve block (see photo). The sciatic nerve, that is, its end branches (peroneal and tibial nerves) appear clearly near the popliteal space on the dorsal side of the distal thigh. The primary anatomic landmark here is the medial border of the long head of the femoral biceps muscle. The nerve is scanned in cross-section, starting dorsally. Should it already be distinct, it can usually be traced as far as the bifurcation by shifting the transducer proximally.

Nota bene: The reverse is of course also possible, i.e. to use ultrasound to block the two end branches selectively, if needed.


Sonoanatomic Landmarks

Medial border of the femoral biceps muscle

lateral distal sono

The Technique

After identification of the optimum puncture location near the bifurcation, this block is carried out at a slant. Depending on patient and puncture height, the whole nerve or merely its end branches are irrigated with local anaesthetic.