[Treatment options for femoroacetabular impingement syndrome and osteoarthritis].

Femoroacetabular impingement syndrome (FAIS) is a prearthritic deformity. Many patients with FAIS show signs of osteoarthritis at the time of initial presentation. Ideally, surgical correction of FAIS should stop the progression of osteoarthritis. However, biological changes in the joint, inflammatory processes, and patient-specific factors, which are not influenced by surgery, show a role in the progression of joint degeneration. Thus, it is not surprising that the results of joint-preserving surgery in FAIS and osteoarthritis Tönnis grade 2 and higher are bad, and patients often need to undergo total hip replacement (THR).Even in patients with initial osteoarthritis (Tönnis grade 1) the results of joint-preserving surgery are significantly worse in comparison to in patients without osteoarthritis. As this pathology occurs mainly in young patients, efforts should be made to avoid THR, as the risk of loosening and revision surgery is increased. Analysis of risk factors that lead to worse outcome in joint-preserving surgery can be helpful. Age > 45 years, adiposity, high alpha angle, CE angle < 25° and female sex are risk factors that lead to worse outcome in patients with risk factors and osteoarthritis Tönnis grade 1, the success rate of joint-preserving surgery after 5 years is below 50%. Therefore, we recommend non-surgical treatment. Promising is the use of mesenchymal progenitor cells (MPCs), even if their routine use has not been established. If conservative therapy is not successful, THR is indicated. With the use of modern bearings, a survival rate of THR of more than 90% after 15 years is reported in patients < 50 years. Patient satisfaction after THR is higher than after joint-preserving surgery.The combination of treatment modalities like joint-preserving surgery in combination with the application of MPCs to both correct the mechanical conflict and also influence progression of osteoarthritis is promising the from a biological point of view.