👉 The collar fluid, also known as collarbone fluid or costoclavicular space fluid, is a serous membrane fluid found in the shallow space between the clavicle (collarbone) and the sternum (breastbone). This fluid plays a crucial role in reducing friction between these bones during arm movements and helps to cushion the area against potential trauma. It is produced by the synovial membrane lining the costoclavicular space and serves to maintain joint health and flexibility, ensuring smooth and pain-free shoulder movement.
