Musculoskeletal diseases constitute a large burden for the health-care system, the society and for each individual patient. With an elderly population (>67 years) increasing by 50% until 2030, and an obesity epidemic, this burden will increase and there is need to develop more effective and better preventive and treatment methods. In musculoskeletal research precise evaluation methods is a prerequisite to reach these goals.

Clinical research is compared to basic research, often dependent on imprecise methods. The number of patients needed to demonstrate a difference between two treatment methods is therefore large. In musculoskeletal research common methods like plain radiographs are imprecise for detecting healing of bone, loss of bone (osteoporosis), body-composition and movement of implants or positions of joints. During the last decades more precise methods have been developed1. We have established a centre for radio-stereometric analysis (RSA) and dual energy x-ray absorptiometry (DXA). With RSA small movements of implants or joints can be measured with a precision of less than 0.1 mm for translation and 0.3° for angular movements. With DXA bone remodelling and body composition can be measured precisely within a few percent.

CIRRO has for several years conducted research within the field of bone and implant research, but the research group did not get a name before in 2008. Prothesis surgery is among the best documented and successful orthopaedic procedures. The implants can be prothesises or osteosynthetic material. The research goals includes selection of patients, surgical techniques, complications and goal achievement. RSA is the main method used. This method may be used in a variety of ways and for all joints in the body. This require a continuous development of the method. Vi validate the RSA method in various contexts.