Type AO-C1 thoracolumbar vertebral fracture-dislocations：four-screw two-rod single-segment reduction fixation / 中国组织工程研究

ABSTRACT

BACKGROUND:The type AO-C1 thoracolumbar acute spine injury is a kind of high-energy instable injury, can cause thoracolumbar fracture-dislocation, and mainly associated with spinal nerve injury. Generaly, al needs to posterior open reduction, decompression, bone graft fusion and multiple-segmental internal fixation of pedicle screw rod system, which causes excessive loss of spinal movement segment and a large number of application of internal fixators. OBJECTIVE:To evaluate the treatment effect of posterior pedicle screw mono-segmental internal fixation for treatment of the type AO-C1 thoracolumbar vertebrae fracture-dislocations. METHODS:From January 2008 to December 2013, 17 cases of type AO-C1 thoracolumbar fracture-dislocation were folowed up. Al patients were treated with one-stage posterior open reduction and pedicle screw-rod fixation. Of them, eight cases received four screws and two rods for single-segment fixation in upper and lower vertebrae adjacent to intervertebral space after dislocation (4-screw 2-rod group). Nine cases received eight screws and two rods for multiple-segment fixation in the upper and lower vertebrae adjacent to intervertebral space after dislocation (8-screw 2-rod group). Operative time and intraoperative blood loss were compared between the two groups. The Cobb’s angle was measured on lateral X-ray film of two groups preoperatively and 1 week postoperatively and during the final folow-up. The neurological function was evaluated by Frankel classification. The visual analogue scale was adopted to assess the degree of low back pain. RESULTS AND CONCLUSION:Patients were folowed up for 1 to 5 years. Significant differences were detected in the operative time between the two groups, and operative time was better in the 4-screw 2-rod group than in the 8-screw 2-rod group (P < 0.05). No significant difference was found in intraoperative blood loss between the two groups. The deformity of fracture-dislocation had been corrected, and the pain of low back had significantly relieved in al patients after fixation. According to Frankel classification, two cases at Grade A were improved to Grade E, but eight cases at Grade A got no improvement after treatment. Two cases at Grade B were also improved to Grade E at the final folow-up. Significant differences in Cobb’s angle and visual analogue scale were detectable at 1 week postoperatively and during final folow-up as compared with preoperatively (P < 0.05), but no significant difference was visible between final folow-up and 1 week postoperatively. No significant difference in Cobb’s angle and visual analogue scale was observed between the 4-screw 2-rod group and 8-screw 2-rod group. Results indicate that there was no significant difference in the clinical efficacy between 4-screw 2-rod single-segment and 8-screw 2-rod multiple-segment fixation for treating type C1 thoracolumbar vertebrae fracture-dislocation. Therefore, AO-C1 thoracolumbar vertebrae fracture-dislocation could be treated with 4-screw 2-rod single-segment reduction fixation.