The local anaesthetic is injected into the fascial space between the muscle fascia of the major pectoral muscle anteriorly and the clavipectoral fascia with the minor pectoral muscle posteriorly
Major pectoral muscle (red asterix), minor pectoral muscle (green asterix), red needle, axillary artery (A), axillary vein (V). The black expansion between the major and minor pectoral muscles around the tip of the needle is the local anaesthetic
