Assessment of the Value of Registries in Shoulder Arthroplasty Using Reverse Arthroplasty as an Example

Introduction As a consequence of the Swedish model, endoprosthesis registers have become increasingly important worldwide. Due to the increasing number of joint replace- ments at the shoulder, these are being increasingly included in the register databases - in addition to interventions at the hip and knee joint. In this study, the value of endoprosthesis registers is investigated, using the example of shoulder endoprosthetics and including a comparison with clinical studies. Material and Methods The annual reports of 32 different endoprosthesis registers with data on hip, knee and/or shoulder arthroplasty were analysed. The number of operations and demographic patient data for all areas of endoprosthetics were examined. In addition, a more detailed consideration of variables such as the primary diagnosis, the cause of the revision, the revision rate depending on risk factors and patient-reported outcome measures (PROM scores) was carried out exclusively for the shoulder joint endoprostheses. Using the example of the inverse shoulder prosthesis, clinical studies were compared to registry data with special regard to the revision rate. Results A total of 20 endoprosthesis registers could be included, 9 of these collected data on shoulder arthroplasty. The main primary diagnoses were osteoarthritis (40.6 %), rotator cuff defect arthropathy (30.2%) and fractures (17.6 %). The most commonly used shoulder joint endoprosthesis was the inverse prosthesis (47.3 %). The proportion of revision surgeries in total shoulder arthroplasty operations was less than 10% in all registers. In addition to the revision rate, the PROM scores were sometimes used in the registers to evaluate the success of the prosthesis. Compared to registry data, clinical studies showed more heterogeneous data with a significantly higher revision rate of over 10% in long-term follow-up - using the example of the inverse shoulder prosthesis. Conclusion Register data are a valuable source of information in shoulder arthroplasty and can make a significant contribution to the quality assurance of endoprosthetic treatments. Compared to clinical studies, they primarily provide data on durability of different endoprosthesis and give lower revision rates. Clinical studies use PROM scores and clinical and radiological examinations to focus only on individual implants and surgical centres on the one hand and much more on the functional results on the other.