Spread of anesthetics in peripheral blocks at the neck-shoulder junction according to the localization of clavicle (case series).

After the brachial plexus blocks, local anesthetics do not diffuse under the clavicle and can spread to the epidural space with a cephalic tendency. We aimed to show how the local anesthetic spread will be according to the integrity of the clavicle by adding contrast agent to the peripheral blocks. We observed that the barrier created by the clavicle at the neck-shoulder junction disappeared in fracture >2 cm and the drug distribution showed a caudal transition. We think that the type and degree of clavicle fracture changes the drug diffusion and affects the success of the block.