ISRCTN10464365.

Trial name or title	A randomised controlled trial to assess the effectiveness of treating subacromial impingement and partial thickness rotator cuff tears with the administration of platelet rich plasma during arthroscopic decompression surgery
Methods	Study design: randomised trial Random sequence generation: computer generated randomisation system Allocation concealment: not reported Masking: not blinded
Participants	Location: unknown Target sample size (N): 34 Inclusion criteria: people with shoulder impingement syndrome or a partial thickness rotator cuff tear, with diagnosis confirmed using ultrasound scan by a trained member of the research team; failed conservative treatment; listed for arthroscopic subacromial decompression; male or female, aged 35‐75 years old Exclusion criteria: full thickness rotator cuff tears; people with a history of significant trauma (fracture, dislocation/instability, etc.), surgery, osteoarthritis or other significant pathology of the affected shoulder not related to the rotator cuff; person is unable to consent for themselves; no conservative treatment; previous surgery on affected shoulder Contraindications to PRP: history of diabetes mellitus; platelet abnormality or platelet count < 100 x 109/L; haematological disorder; serum haemoglobin < 11 g/dL; use of systemic cortisone; use of any anticoagulant; evidence of gangrene/ulcers or peripheral vascular disease; history of hepatic or renal impairment or dialysis; person is known to have a psychological, developmental, physical, emotional or social disorder that may interfere with compliance with study requirements; history of alcohol or drug abuse; person has a religious or cultural conflict with the use of platelet gel treatment or blood products; has inadequate venous access for blood draw; is currently receiving or has received radiation or chemotherapy within the last 3 months prior to the study; pregnant women, or women who are lactating or planning pregnancy during the course of the study; any other significant disease or disorder that, in the opinion of the Investigator, may either put the participants at risk because of participation in the study, or may influence the result of the study, or the participant's ability to participate in the study
Interventions	PRP: subacromial decompression plus an autologous PRP concentrate injection into the rotator cuff tendon (gel sprayed directly to the decompression area) Controls or placebo or no intervention (standard care): subacromial decompression (alone)
Outcomes	Primary outcomes: Oxford Shoulder Score Secondary outcomes: functional shoulder assessments; EQ5D; Oxford Satisfaction Index Timing of outcomes measurement: baseline and 3 weeks, 3, 6, 12 months posttreatment
Starting date	Main ID: ISRCTN10464365 Date of registration: January 2011 Last refreshed on: June 2013 Date of first enrolment: unknown Status: completed
Contact information	Name: Andrew Carr Address: Windmill Road, Headington, Oxford Telephone: Email: andrew.carr@ndorms.ox.ac.uk Affiliation: University of Oxford
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