IntroductionLonger life expectancy is accompanied by a higher incidence of fragility fractures of the pelvis (FFP), which has repercussions on mortality and nursing home admissions. Given the paucity of data at French healthcare facilities, we carried out a retrospective study to (1) evaluate how surgical treatment of FFP with posterior displacement (type III and IV according to Rommens and Hofmann) affects a patient's pain, functional status and ability to stay at home and (2) evaluate the postoperative complications and mortality rate. HypothesisSurgery for posteriorly displaced FFP will relieve pain and preserve the patient's independence. MethodsAll the patients over 65 years of age who were operated on for a posterior FFP between January 2015 and August 2020 were included in this prospective, single-center study. The demographics, fracture type, details of the surgical treatment, complications and mortality were analyzed. Pain (visual analog scale, VAS), functional status (Activity of Daily Living [ADL] and Instrumental Activity of Daily Living [IADL]), mobility (Parker score) and rates of nursing home admissions were compared before the fracture, after surgery and at a mean follow-up of 28 months (minimum follow-up of 1 year). ResultsForty-eight patients with a mean age of 75 years were included. Twenty-four of these patients (50%) had at least two comorbidities. The FFPs were either type IV (31/48; 65%) or type III (17/48; 35%). The mean VAS for pain was significantly lower on the first day postoperative (3.5 versus 4.8; p=0.02). This significant reduction continued upon discharge from the hospital (1.95; p=0.003) and persisted at the mean follow-up of 28 months (2.2; p=0.64). The complication rate was 15% (7/48) and the mortality rate at the final review was 15% (7/48). Among the surviving patients, 81% (29/36) returned to living at home. The ADL (5.1 versus 5.8; p=0.09), IADL (5.9 versus 6.9; p=0.15) and Parker score (6.8 versus 8.2; p=0.08) at the final review were not significantly different from the values before the fracture. ConclusionThis is the first French study of patients operated on for an FPP. Fixation of posteriorly displaced fractures allows surviving patients to retain their mobility. Pain relief is achieved quickly and maintained during the follow-up period. Thus, our initial hypothesis is affirmed. The complication rate is not insignificant; given the complexity of this surgery, percutaneous treatment is preferable. Level of evidenceIV; retrospective study.