What is the space between the breast and the pectoral muscle called?

The space between the breast and the pectoral muscle is known as the retromammary space. This area functions as a potential space, providing a cushion that allows for the movement of the breast over the underlying pectoral muscle. It contains loose connective tissue and is clinically significant, as it can be a route for the spread of breast cancer and other diseases. Understanding this anatomical feature is crucial for medical professionals when considering surgical interventions or assessing diseases related to the breast.