BACKGROUND:Pelvic fractures encompass a range of types,and the utilization of a pelvic reduction frame for restoration often lacks a systematic repositioning method.Instead,it relies on the operator's experience in conjunction with fluoroscopic findings,which can lead to uncertainty and non-reproducibility. OBJECTIVE:To investigate the clinical efficacy of combining computer-simulated repositioning techniques with a pelvic reduction frame for the treatment of anteroposterior compression-III pelvic fractures. METHODS:A retrospective analysis was conducted on 19 patients with anteroposterior compression-III pelvic fractures who underwent preoperative repositioning via computer simulation and intraoperative repositioning with the assistance of a pelvic reduction frame between January 2018 and December 2021.Among them,7 cases were fixed with double plate in anterior ring and 12 cases were fixed with single plate combined with anterior subcutaneous internal fixation(INFIX).All patients received posterior ring fixation with two sacroiliac screws.Operative duration,intraoperative reduction time,the frequency of intraoperative fluoroscopy use,blood loss,and follow-up duration were documented.These data were utilized to monitor fracture healing time and postoperative complications.Fracture reduction quality was evaluated according to the Matta scale,and the Majeed Pelvic Function Score was employed to assess patient function during the final follow-up. RESULTS AND CONCLUSION:(1)Surgery was successfully completed in all 19 patients.The anterior ring was secured with double plates in 7 cases,while a single plate combined with INFIX was utilized in 12 cases.The posterior ring was stabilized with two sacroiliac screws,specifically targeting the S1 and S2 cones.(2)The operation duration ranged from 74 to 147 minutes,with a mean of(101.63±19.55)minutes.Intraoperative repositioning took place over a period of 26 to 41 minutes,with a mean of(38.11±3.31)minutes.The number of intraoperative fluoroscopies conducted ranged from 35 to 81,with a mean of(62.68±13.11)times.Intraoperative bleeding volumes varied from 60 to 130 mL,with a mean of(85.37±20.57)mL.(3)All the patients were diligently monitored for a duration of 12 to 26 months.Fracture healing was observed within a time frame of 12 to 20 weeks,with a mean of(16.37±2.50)weeks.(4)The evaluation according to Matta's criteria one day post-surgery revealed excellent outcomes in 14 cases and good outcomes in 5 cases.At the final follow-up,the Majeed function score indicated excellent results in 16 cases and good results in 3 cases.(5)Two patients experienced localized fat liquefaction phenomena,characterized by redness,swelling,and oozing at the incision site,which gradually resolved with proactive dressing changes.None of the patients encountered complications such as internal fixation loosening,loss of fracture reduction,or nerve injuries post-surgery.It is concluded that the combined approach of using computer-simulated repositioning techniques in conjunction with pelvic reduction frames for the treatment of anteroposterior compression-III pelvic fractures has advantages in enhancing repositioning efficiency and improving pelvic function.