Abstract: BACKGROUND: Recently, percutaneous minimally invasive pedicle screw fixation systems have become a popular treatment option for thoracolumbar fractures due to ongoing innovation in orthopedic internal fixation devices. Currently, while many studies compare the effectiveness of open pedicle screw fixation through or across the fractured vertebra, fewer studies compare these two methods when using navigation-assisted percutaneous minimally invasive techniques. 
OBJECTIVE: To compare the clinical efficacy of percutaneous minimally invasive pedicle screw fixation in the treatment of thoracolumbar fracture through and across the injured vertebra.
METHODS: A retrospective analysis was performed on 67 patients with single level thoracolumbar fracture without spinal cord nerve injury who were treated in the Department of Spine Surgery, Affiliated Hospital of Yan'an University from October 2021 to June 2023. All of them were treated with percutaneous pedicle screw fixation with the assistance of computer navigation, and were followed up to 6 months after surgery. The injured vertebrae were divided into transinjured vertebrae group (n=35) and cross-injured vertebrae group (n=32) according to whether or not the injured vertebrae were nailed. The general data, perioperative data, anterior vertebral height ratio, Cobb angle, visual analog scale score and Oswestry disability index of injured vertebra were compared before and after treatment between the two groups. Clinical efficacy of minimally invasive percutaneous transvertebral fixation and transvertebral fixation in thoracolumbar fracture patients without spinal cord nerve injury was compared. 
RESULTS AND CONCLUSION: (1) There was no significant difference in preoperative general data between the two groups (P > 0.05), indicating comparability. (2) Intra-group comparison: anterior vertebral height ratio, Cobb angle, visual analog scale score and Oswestry disability index score of the injured vertebra were significantly improved 7 days and 6 months after surgery in both groups (P < 0.05). (3) Comparison between groups: The operative time, intraoperative blood loss, incision length, and intraoperative fluoroscopy times in the transinjured vertebrae group were significantly lower than those in the cross-injured vertebrae group, respectively; the differences were statistically significant (P < 0.05). However, there was no significant difference in hospitalization days between the two groups (P > 0.05). There was no significant difference in anterior vertebral height ratio, Cobb angle, visual analog scale score and Oswestry disability index score between the two groups at 7 days and 6 months after surgery (P > 0.05). (4) It is suggested that for patients with single level thoracolumbar fracture without spinal cord nerve injury, minimally invasive percutaneous pedicle screws across injured vertebrae have the advantages of shorter intraoperative time, less bleeding, smaller surgical incision, and low number of fluoroscopies than transinjured vertebrae. In short- and medium-term follow-up, both percutaneous minimally invasive transvertebral fixation and transvertebral fixation can effectively restore and maintain the height of the injured vertebra, correct kyphotic deformity, restore spinal stability and reduce pain, and obtain excellent clinical results. Less invasive transvertebral percutaneous fixation is recommended for patients with thoracolumbar fracture of AO type A with normal body mass index and no spinal nerve injury or posterior ligament complex injury.

Key words: navigation, thoracolumbar fracture, percutaneous pedicle screws, transinjured vertebrae, cross-injured vertebrae