Efficacy comparison between minimally invasive fixation and routine fixation of tracer in robot-assisted pedicle screw placement / 中华创伤杂志

ABSTRACT

Objective@#To investigate the clinical efficacy of modified tracer minimally invasive fixation in robot-assisted pedicle screw placement.@*Methods@#A prospective randomized controlled study was conducted to analyze the clinical data of 41 patients with thoracolumbar fresh fracture at the orthopaedics department of Karamay Central Hospital from July 2017 to December 2017. There were 20 males and 21 females, aged 25-55 years, with an average of 40.6 years. According to AO fracture typing, there were 28 patients with type A and 13 patients with type B. The patients underwent robot-assisted pedicle screw placement. Random number table method was used to divide the patients into the conventional group (20 patients) and modified group (21 patients). The conventional group was treated with conventional tracer fixation, and the modified group modified tracer minimally invasive fixation. A total of 92 pedicle screws were implanted in the conventional group and 96 pedicle screws were implanted in the modified group. The size of wound, wound bleeding, time of fixing the tracer, complications (spinal cord injury and nerve root injury when fixing the tracer), development of the tracer fixator and artifacts were recorded. The accuracy of nail placement was evaluated by 320-slice CT scan and Gertzbein-Robbins criteria.@*Results@#There was no significant difference in age, sex, diagnosis, transverse diameter of pedicle and e angle between the two groups (P>0.05). The wound size, wound bleeding, and time of fixing the tracer in the modified group were (6.00±1.26)mm, (1.38±0.22)ml and (1.42±0.17)minutes, respectively, while those of the conventional group were (40.16±5.71)mm, (11.61±1.15)ml, and (5.12±0.64)minutes respectively (P<0.05). No spinal cord or nerve root injury occurred in either group when the tracer was fixed. In the process of three-dimensional image acquisition and automatic registration, the tracer fixator in the modified group developed with Kirschner needle without artifacts, and the tracer in minimally invasive fixator had good fluoroscopy effect. The modified group included 94 pedicle screws of type A and two of type B according to Gertzbein-Robbins criteria. The conventional group included 89 pedicle screws of type A and three of type B according to Gertzbein-Robbins criteria. There was no significant difference in the screw placement accuracy between the two groups (P>0.05).@*Conclusion@#In the robot-assisted pedicle screw placement, the modified tracer minimally invasive fixation method is safe and less traumatic, with no side effect on the accuracy of pedicle screw placement.