Reverse or Anatomical (replacement) for Painful Shoulder Osteoarthritis: Differences between Interventions. Acronym; RAPSODI

Background Currently patients who have painful osteoarthritis of the shoulder joint and have an intact rotator cuff, having exhausted conservative treatments, are offered a shoulder replacement. Usually an anatomical replacement (aTSR) is done. It closely mirrors the normal anatomy and needs intact tendons around the shoulder (rotator cuff) to allow the patient to lift the arm above shoulder height. The most common reason for revision of aTSR is rotator cuff failure. Increasingly in patients aged > 60 years surgeons are using a reverse total shoulder replacement (rTSR), which can be used in patients with rotator cuff failure. Surgeons believe that patients recover more quickly, outcomes are more consistent and there is lower risk of revision. To date there are no randomised controlled trials (RCT) comparing the two types of implant in this patient group. A Cochrane review (2020) reported a lack of high-quality studies and it is uncertain whether rTSR has better outcomes than aTSR. Aims and objectives The trial aims to investigate whether rTSR is superior to aTSR for the treatment of painful osteoarthritis of the glenohumeral joint with an intact rotator cuff in patients over the age of sixty years as measured by patient rated pain and function using the Shoulder Pain and Disability Index (SPADI) at 24 months adjusted for baseline SPADI score, and whether this is a cost-effective treatment option. Additional objectives are analysis of secondary outcomes including the Oxford Shoulder Score, rate of recovery of pain and function, adverse events and EQ-5D-5L to estimate cost-effectiveness, and a qualitative exploration of patients’ experiences, goals, and perceptions of acceptability of shoulder arthroplasty and recovery over time. We will report the rate of revision and mortality. Methods The trial is a pragmatic multi-centre two-parallel group superiority RCT with masking of patients and assessors. It includes an eight-month internal pilot together with a full health economic analysis and a nested qualitative interview study. The research will be undertaken in NHS shoulder arthroplasty units in England and Wales. Patients will be screened for eligibility (suitable for shoulder arthroplasty and intact rotator cuff) and invited for recruitment prior to surgery. We need data from 364 participants at 24 months to provide 90% statistical power to establish the superiority of rTSR over aTSR, determined by a greater than 8 points SPADI difference between the two implants. Timelines for delivery The study will be of 62 months duration: 6 months set up, 8 months internal pilot; 16 months main trial recruitment; 24 months follow up; 8 months data cleaning, checking, analysis and reporting. Anticipated impact and dissemination This trial will improve decision making about which type of shoulder replacement to offer patients aged 60 years and over with osteoarthritis and an intact rotator cuff. Targets for dissemination will include NICE, Clinical Commissioning Groups, Department of Health and Social Care and the Specialty Advisory Committee (for the curriculum for clinicians who do these procedures). Results will be presented at professional meetings and published in high impact journals. A summary of results will be developed in plain English for patient focused outlet.