Preliminary application of Starr reduction framecombined with O-arm navigation systemin the treatment ofcomplex pelvic fractures

Abstract

Objective To investigate the feasibility and short term clinical efficacy of early minimally invasive treatment of complex pelvic trauma with Starr reduction frame combined with O-arm navigation system. Methods From June 2017 to December 2018, thirty two patients with Tile C complex pelvic fractures were prospectively divided into two groups according to the random number table. The open treatment group included 17 cases (open reduction and internal fixation group; 10 males and 7 females, age 24-60 years, average 37±6.5 years; according to Tile classification, 8 cases of C1 type, 8 cases of C2 type and 1 case of C3 type; according to the Denis classification of sacral fractures, 9 cases in zone I, 6 cases in zone II and 2 cases in zone III). The combined treatment group included 15 cases (Starr reduction frame group combined with O-arm navigation system, 8 males and 7 females, age 32-57 years, average 40±5.2 years; according to Tile classification, 8 cases of C1 type, 6 cases of C2 type and 1 case of C3 type; according to the Denis classification of sacral fractures, 8 cases in zone I, 5 cases in zone II and 2 cases in zone III). The ilioinguinal and Stoppa approaches were used in the open treatment group, and the anterior and posterior ring injuries were fixed with reconstruction plate screws and hollow screws, respectively. In the combined treatment group, starr frame was used to assist reduction, combined with O arm navigation technique, infix internal fixation frame, superior pubic branch screw, sacroilium screw were used to fix the anterior and posterior ring injury. The quality of pelvic fracture reduction was evaluated by the Matta scoring system, and the Majeed score was used to evaluate the clinical efficacy. Results All patients were followed up for 6 to 12 months. The hospitalization time (45±11 d), operation time (220.0±49.4 min) and fracture healing time (24.0±5.6 weeks) in the open treatment group were longer than those in the combined treatment group (21±9 d, 180.0±24.2 min, 16.1±3.8 weeks), and the intraoperative blood loss (820.0±140.4 ml) was significantly higher than that in the combined treatment group (24.0±10.4 ml)(t=6.651, 2.772, 6.128, 22.874; all P< 0.05). According to Matta scoring system, in the open treatment group, there are 8 excellent cases, 6 good cases, 2 fair cases, 1 poor case, thus the excellent and good rate was 82.4%(14/17). While 9 cases were excellent, 5 good, 1 fair, and the excellent and good rate was 93.3% (14/15) in the combined treatment group. At the latest follow-up, Majeed score was 51-85 points in the open treatment group, including excellent in 8 cases, good in 6 cases, fair in 2 cases, poor in 1 case, thus the excellent and good rate 82.4% (14/17), and the Majeed score was 75-95 points in the combined treatment group, including excellent in 9 cases, good in 5 cases, fair in 1 case, thus excellent and good rate 93.3% (14/15). There was a statistically significant difference between the two groups of Matta score and Majeed score (χ2=0.034, 0.040; P< 0.05). Surgical infection occurred in 4 cases in the open treatment group and healed after debridement and treatment with sensitive antibiotics. The incidence of complications was 23.5% (4/17). In the combined treatment group, 2 cases had anterolateral thigh skin sensory loss after operation, and the symptoms were relieved after mannitol, mecobalamine treatment and removal of internal fixations. One patient had hematoma of the gluteus maximus muscle after operation. The result of angiography showed that the INFIX screw was too long and perforated near the foramen of the ischium, resulting from the injury of the superior gluteal artery. After stopping the use of anticoagulant, intravenous infusion of tranexamic acid, blood transfusion, etc., the patient was cured and discharged from hospital. The incidence of complications was 20.0% (3/15). There was no significant difference in the incidence of complications between the two groups. Conclusion With the help of starr reduction frame, the early reduction and minimally invasive treatment of pelvic fracture can be realized, and the amount of intraoperative bleeding can be reduced. The combined application of o arm navigation can improve the accuracy and safety of sacroiliac screw and anterior column screw placement, reduce the radiation dose and frequency of operators and patients, shorten the operation time and improve the curative effect. Key words: Pelvis; Fractures, bone; Fracture fixation, internal; Surgery, computer-assisted