Ultrasound is extremely useful for the superficial structures of the shoulder.  Imaging of the rotator cuff and biceps yields excellent diagnostic information.  Ultrasound also allows for better accuracy of injections.  Studies have shown that experts in shoulder surgery can miss the subacromial bursa up to 30% of the time when performing injections without ultrasound.  When ultrasound is used for injections, studies have also shown that pain can be significantly reduced.