Table 1 Eligibility criteria

Criteria

Inclusion criteria

Patients were included in the study if they had all of the following:

Shoulder pain for more than 6 months

Shoulder pain scores more than 5 on a numeric rate scale for pain of 0–10.

Diagnosed clinically as RC tear, painful mid-arc and/or positive Hawkins-Kennedy, drop arm, empty can, and lateral jobe tests [15,16,17].

Diagnosed with non-calcific supraspinatous partial thickness tear of less than 50% of the tendon thickness upon sonographic examination.

No or little response to conservative treatment for 3 months (one course of NSAIDs, one course of 3 weeks physiotherapy, and one local corticosteroid injection).

Exclusion criteria

Patients were excluded in the study if they had any of the following:

Obvious pathology of the shoulder, such as calcified tendon by US examination, full thickness tear, partial tear equal or greater than 50% of the tendon thickness, tear of other rotator cuff tendons rather than supraspinatous tendon.

Inflammatory, advanced degenerative, or septic arthritis of the shoulder

Referred and radiculopathy pain.

Previous surgery to the same shoulder.

NSAID use in the past 2 weeks or corticosteroid injection within 6 weeks before the study.

The unstable medical condition, a known uncontrolled systemic disease, cardiac pacemaker, pregnancy, or psychiatric problems.

Thrombocytopenia (< 150,000 platelets/ml), anti-platelet and anti-coagulant medications, platelet/bleeding disorders.

Refused or unable to sign a consent