Acetabular fractures are complex, relatively rare lesions that are difficult to manage. Given the surgical challenge they represent, they are often managed by expert centers. The overall incidence of these fractures is around 3 fractures/100,000 persons/year.

It is now well established that the quality of the reduction obtained is an important predictive factor of the postoperative outcome in patients with displaced acetabular fractures. Obtaining an anatomical reduction, at least satisfactory, is not always easy, even in trained teams. Indeed, it can be difficult because of the structural environment. This is due to the proximity of the acetabulum to the vasculo-nervous elements, but also to the complexity of the fracture itself. The contribution of new technologies appear to be important tools to achieve this objective. Indeed, investigators have demonstrated that the use of the O-ARM imaging system (Medtronic®, Sofamor, Memphis, TN) allowed the improvement of their results.

Although they occur more frequently in the elderly population, the average incidence is maintained in the 20-59 age group. In these young populations, the fracture occurs most frequently as a result of a high-energy mechanism (road accident, more exceptionally, during a sporting activity). These patients, in the prime of their lives, are often athletic. The desire to resume sports after surgery is a powerful motivating factor for these patients. Often, it is the primary measure of surgical success from the athlete's perspective. In a previous work, Giannoudis et al. reported a 42% rate of return to activity at the previous level. The quality of the surgery is associated with the possibility of resuming sports activity after the procedure.

Thus, the objective of this work is to determine the results of acetabular surgery in a population of previously athletic patients, in particular the return to athletic performance.

Inclusion Criteria:

• Patients aged 18 to 45 years at the time of surgery at Saint Joseph Hospital
• Patients with an isolated acetabulum fracture
• Patients with intraoperative management with O-Arm
• Patients with at least 2 years of follow-up
• French-speaking patients

Exclusion Criteria:

• Presence of pre- or post-operative neurological lesions
• Presence of associated fractures
• ASA (American Society of Anesthesiologists) score ≥ 3
• Absence of pre- and postoperative CT scans available on PACS
• Patients under guardianship or curatorship
• Patients deprived of liberty
• Patients under court protection
• Patients objecting to participation in the study
• Low preoperative physical activity (= UCLA Activity Score ≤ 5)
• Unsatisfactory criteria for surgical reduction on CT scan

Patients aged 18 to 45 years at the time of surgery at Saint Joseph Hospital, victims of an isolated acetabulum fracture, having received intraoperative management with O-ARM, with at least 2 years of follow-up