Subacromial bursa injection The most commonly treated area around the shoulder joint with injections. Indications: subacromial bursitis, impingement syndrome, rotator cuff injury. Anatomy: The subacromial bursa is connected to the subdeltoid bursa and is located deep to the deltoid muscle. The distal end of the bursa is located on the surface of the supraspinatus muscle, and the role of this bursa is to protect the supraspinatus muscle from friction with the acromion. Physical examination: Abduction and internal rotation of the shoulder joint can cause compression of the bursa located between the greater tuberosity of the humeral head and the acromion and rostro-capital ligament, and the neer test and the hawkins and Kennedy tests. Risks of blind puncture: The success rate of blind puncture is approximately 29%. Common mispenetrations include entry into the deltoid, glenohumeral, and rotator cuff ligaments. Ultrasound-guided puncture technique: The patient is seated with the upper extremity down (if necessary, an assistant can pull down on the patient’s upper extremity to increase the bursa gap) The probe is located parallel to the scapular gonad above the acromion, and the supraspinatus tendon is seen below the acromion, across the humeral head to the greater tuberosity. The tendon is usually hyperechoic and the subacromial bursa is liquid hypoechoic above the tendon, normally narrow and possibly widened in the presence of bursitis. Calcified spots within the tendon can also be observed on ultrasound.