Multicentre SMS Study - FR

Inclusion Criteria: * Patient suffering from a severely painful and/or disabling hip joint due to osteoarthritis, traumatic arthritis, developmental dysplasia of the hip, or avascular necrosis of the femoral head, and requiring a total hip replacement. * Patient who will receive a Medacta SMS femoral stem. * Patient agrees to comply with the study requirements. * Patient has signed the consent form. * Patient is affiliated with a social security system. * Patient aged 18 to 75 years Exclusion Criteria: * Participation in biomedical research. * Minor patient. * Protected adult patient. * Vulnerable individuals as defined by Article L1121-6 of the Public Health Code. * Pregnant or breastfeeding women. * Patient unable to express their non-opposition. * Patient refusing the collection of their personal data. * Acute, systemic, or chronic infection. Skeletal immaturity. * Grossly deformed anatomy (at the surgeon's discretion). * Osteomalacia for which the fixation of an uncemented implant is contraindicated. * Patient suffering from active rheumatoid arthritis or osteoporosis. * Patient with metabolic disorders likely to impair bone formation when the fixation of an uncemented implant is contraindicated. * Patient suffering from muscle atrophy or neuromuscular disease. * Patient with an allergy to the implant material. * Any patient who cannot or does not wish to give their informed consent to participate in the study. * Patient whose prospects of regaining independent mobility would be compromised by known coexisting medical problems. * Any contraindication mentioned in the instructions for use of the investigational medical device.