[A multicenter retrospective study assessing pelvic unlocking closed reduction device for reducing unstable pelvic posterior ring disruption]

Objective: To explore the application value and effectiveness of pelvic unlocking closed reduction device for the treatment of unstable pelvic posterior ring disruption.

Methods: A retrospective analysis of clinical data of 243 cases of unstable pelvic posterior ring disruption treated with pelvic unlocking closed reduction device in 13 orthopaedic trauma centers across the country between December 2018 and June 2020 was performed. There were 139 males and 104 females; the age ranged from 18 to 92 years, with an average age of 48.5 years. The cause of injury included 132 cases of traffic accident injuries, 102 cases of falling from height, and 9 cases of crushing injuries. According to AO/Orthopaedic Trauma Association (AO/OTA) classification, there were 5 cases of type 61-B1, 13 cases of type 61-B2, 32 cases of type 61-C1.1, 47 cases of type 61-C1.2, 89 cases of type 61-C1.3, 35 cases of type 61-C2, and 22 cases of type 61-C3. The time from injury to operation was 2-121 days, with a median of 10 days. Preoperative preparation time, installation time of unlocking closed reduction device, fracture reduction time, intraoperative fluoroscopy times, intraoperative blood loss, and surgical complications were recorded, and Matta scoring standard was used to evaluate the quality of fracture reduction. According to Matta evaluation results, the patients were divided into two subgroups: excellent-good group and fair-poor group. The differences in gender, age, time from injury to operation, AO/OTA classification, and perioperative clinical indicators were compared between the two groups, and the effects of baseline data and perioperative indicators on the quality of fracture reduction were studied.

Results: Pelvic unlocking closed reduction device did not interfere with the display of the pelvic structure and fracture displacement direction during the intraoperative fluoroscopy, effectively correcting the displacement of the pelvic ring. The preoperative preparation time was 17-60 minutes, with an average of 30 minutes; installation time of unlocking closed reduction device was 10-32 minutes, with an average of 21 minutes; intraoperative fracture reduction time was 15-205 minutes, with an average of 49.2 minutes; intraoperative fluoroscopy times were 41-420 times, with an average of 132 times; intraoperative blood loss was 40-1 500 mL, with an average of 71.5 mL. The reduction quality of pelvic fracture was evaluated according to Matta score immediately after operation. The results were excellent in 153 cases, good in 61 cases, fair in 24 cases, and poor in 5 cases. The excellent and good rate was 88.1%. Further subgroup analysis showed that there was no significant difference in other indexes ( P>0.05) between the excellent-good group and the fair-poor group except for the time from injury to operation and AO/OTA classification ( P<0.05). Among them, the excellent-good reduction rate was 92.2% (119/129) in patients with injury-to-operation time less than 10 days, and the fair-poor reduction rate was 25.7% (9/35) and 40.9% (9/22) in patients with AO/OTA 61-C2 and 61-C3 types, respectively. There was no surgery-related complication due to the application of the pelvic unlocked reduction device, no secondary iliac fractures, vascular, or nerve injuries, and postoperative CT showed that all channel screws were located in the osseous channel.

Conclusion: The pelvic unlocking reduction device can effectively help to reduce the unstable pelvic posterior ring and maintain reduction, meet the needs of different projection angles of pelvic fracture with intraoperative C-arm fluoroscopy. The system facilitate the operation of pelvic reduction and precise fixation.