To evaluate the correlations between structure of supraspinatus tendon (impingement, tendinopathy or partial tear, as well as full thickness tear) on ultrasonography and its response to subacromial hyaluronic acid injection in rotator cuff disease patients

Objective: To evaluate the correlations between structure of supraspinatus tendon (impingement, tendinopathy or partial tear, as well as full thickness tear) on ultrasonography and its response to subacromial hyaluronic acid injection in rotator cuff disease patients and also investigate the factors associated with clinically important improvement after subdeltoid hyaluronic acid for rotator cuff disorder.

Design: Prospective, longitudinal comparison study.

Participants: Patients with rotator cuff disease

Intervention: Three subacromial injection with hyaluronic acid with 2 week-interval.

Main Outcome Measures: Visual analog scale (VAS) of the shoulder pain, Constant score, SPADI score, and angles of active shoulder range of motion (flexion, abduction, external rotation, and internal rotation) at pre-treatment, post-treatment at week 4 and post-treatment at week 12.

Inclusion criteria were patients

1. with clinically and ultrasonographically diagnosed rotator cuff disease of the shoulder-impingement, tendinosis and tear;
2. who reported shoulder pain more than 3 months;

Exclusion Criteria:

1. presence of another medical or psychological condition, including cancer, rheumatoid arthritis, endocrine disease (i.e., diabetes), major depression, or schizophrenia;
2. previous major trauma history at currently affected shoulder; 3 primary osteoarthritis of the glenohumeral joint in a simple radiograph; 4previous injection history at the affected shoulder within 3 months

outcome assessor does not know the rotator cuff condition of patients