Shoulder bursitis

A bursa is a fluid filled sac located between shoulder muscle tendons and bone that reduces friction between these structures. Habitually overloading the associated tendons can over compress your bursa leading to chronic irritation and pain.

Over time the bursa may even become calcified.

The most common bursa affected in the shoulder is located beneath your outer shoulder muscle (deltoid) called the subacromial bursa. Over compressing this bursa gives rise to pain at the tip of your outer shoulder that often radiates down the outer arm, especially when doing overhead activities.