ObjectiveTo evaluate the effectiveness of TiRobot-assisted surgery by O-arm navigation system for percutaneous minimally invasive treatment of posterior pelvic ring injury. Methods The clinical data of 76 patients with posterior pelvic ring injury between January 2016 and June 2021 were retrospectively analyzed. Among them, 45 cases were treated with minimally invasive percutaneous sacroiliac screw fixation assisted by TiRobot and O-arm navigation system (study group), 31 cases were treated with minimally invasive percutaneous sacroiliac screw fixation under the guidance of C-arm X-ray machine (control group). There was no significant difference in gender, age, cause of injury, Tile classification, time from injury to operation between the two groups (P>0.05). The operation time, intraoperative blood loss, the times of nail track adjustment, and intraoperative fluoroscopy times were recorded. The quality of fracture reduction was evaluated by Matta score. At last follow-up, Majeed score was used to evaluate the recovery of pelvic function. ResultsA total of 72 screws were implanted in the study group, with a median of 1 (1, 2) screws per patient. In the control group, 47 screws were implanted, with a median of 1 (1, 2) screws per patient. There was no significant difference in the number of screws between the two groups (Z=−0.392, P=0.695). The operation time, intraoperative blood loss, times of nail track adjustment, and intraoperative fluoroscopy times in the study group were significantly less than those in the control group (P<0.05). All patients were followed up 6-24 months (mean, 14 months). No serious complications was found after operation and during follow-up. Matta score was used to evaluate the quality of fracture reduction at 1 week after operation, and there was no significant difference between the two groups (Z=−1.135, P=0.256). At last follow-up, there was no significant difference of Majeed score between the two groups (Z=−1.279, P=0.201). ConclusionTiRobot-assisted surgery by O-arm navigation system is a reliable surgical method for the treatment of posterior pelvic ring injury, which can reduce the operation time and fluoroscopy times when compared with the traditional operation under the guidance of C-arm X-ray machine. The safety, accuracy, and efficiency of the operation were improved.
ObjectiveTo investigate the effectiveness of TiRobot-assisted percutaneous sacroiliac cannulated screw fixation in the treatment of posterior pelvic ring injuries with sacral variations, and to evaluate its feasibility and safety. Methods The clinical data of 7 patients with Tile type C pelvic fractures and sacral variations treated with TiRobot-assisted percutaneous sacroiliac cannulated screw fixation between January 2020 and June 2021 were retrospectively analyzed. There were 5 males and 2 females with an average age of 36 years (range, 17-56 years). The causes of injury were traffic accident in 4 cases and falling from height in 3 cases. According to Tile classification of pelvic fractures, there were 1 case of type C1.1, 1 case of type C1.2, and 5 cases of type C1.3; according to Denis classification of sacral fractures, there were 3 cases of zone Ⅰ and 4 cases of zone Ⅱ; sacral deformities included 3 cases of lumbar sacralization, 2 cases of sacral lumbarization, and 2 cases of accessory auricular surface of the sacrum. The time from injury to operation ranged from 2 to 7 days, with an average of 4.6 days. The implantation time of each screw, the fluoroscopy times of each guide pin, the quality of fracture reduction (according to Matta score), the excellent and good rate of screw position, the healing time of fracture, and the incidence of complications were recorded, and the effectiveness was evaluated by Majeed score. Results A total of 13 screws were implanted during the operation, the implantation time of each screw was 10-23 minutes, with an average of 18.2 minutes; the position of the guide pin was good, and no guide pin was adjusted, the fluoroscopy times of each guide pin were 3-7 times, with a median of 4 times. Postoperative imaging data at 3 days showed that the position of sacroiliac screw implantation was evaluated as excellent. No complication such as incision infection or vascular nerve injury occurred, and no adverse events related to robotic devices occurred. At 3 days after operation, according to Matta score, the quality of fracture reduction was excellent in 6 cases and good in 1 case, and the excellent and good rate was 100%. All the 7 patients were followed up 6-15 months, with an average of 12.4 months. Bone union was achieved in all patients, and the healing time ranged from 18 to 24 weeks, with an average of 21.2 weeks. Majeed score at last follow-up was 81-95, with an average of 91.5; 5 cases were excellent, 2 cases were good, and the excellent and good rate was 100%. ConclusionTiRobot-assisted percutaneous sacroiliac cannulated screw fixation for posterior pelvic ring injury with sacral variation is accurate, safe, minimally invasive, and intelligent, and the effectiveness is satisfactory.