SummaryThe application of ultrasonography in guiding and controlling the path of the stimulating needle to the brachial plexus via the posterior approach (Pippa technique) was studied. In 21 ASA physical status 1 and 2 patients, scheduled for surgery of the shoulder or upper arm, needle insertion was monitored by ultrasonography and the interaction between needle, surrounding structures and brachial plexus was followed. During injection, the spread of local anaesthetic was visualised and a prediction of block success was made. One failure was predicted. Complete block was achieved in 20 (95%) patients. One potential complication, puncture of the carotid artery, was prevented using ultrasound. Ultrasound is a useful tool in the training and performance of a neurostimulation-guided brachial plexus block by the posterior approach. Ultrasonographic guidance may prevent serious complications associated with this approach to the brachial plexus.