4 – Scanning technique

Place the patient in the sitting position with the humerus rotated 45 degrees internal and the elbow flexed 90 degrees and the hand resting on the thigh

Place the high-frequency linear probe in the parasagittal plane along the long axis of the humerus distal to the postero-lateral margin of the acromion

Identify the surgical neck of the humerus and the crossing pulsatile posterior circumflex humeral artery (use color or power Doppler) and the adjacent axillary nerve or its anterior branch (see next page)

Insert the needle with in-plane technique from the cranial end of the probe

Penetrate the fascia of the deltoid muscle and place the needle tip just cranial to the posterior circumflex humeral artery

Inject 5-10 mL of local anaesthetic until complete perineural spread is obtained