Objective To investigate the efficacy of the pedicle screw fixation and allograft bone in posterior spinal fusion for the treatment of thoracolumbar vertebral fractures. Methods From September 2006 to March 2008, 105 cases of thoracolumbar vertebral fractures were treated with allograft bone in posterior spinal fusion after the pedicle screw fixation,including 75 males and 30 males aged 15-65 years (mean 37 years). The mixture which consisted of spinous process and vertebral plate sclerotin and homogeneity variant bone was used as bone graft to implant into articular process and processus transversus space or vertebral plate space. The time from injury to surgery varied from 8 hours to 21 days, with an average of 3 days. There were 52 cases of fall ing injuries from height, 35 cases of traffic accident injuries, 11 cases of bruise injuries and 7 cases of tumbl ing injuries. Before operation, the primary cl inical symptoms of patients included local pain combined with l imitation of activity, 30 cases compl icated by various degrees of spinal cord and nerve root functional disturbance. According to Mcaffee classification, there were 7 cases of flexion depressed fractures, 86 cases of blow-out fractures, 9 cases of Chance fractures and 3 cases of dislocation-fracture. According to Frankel grade, there were 11 cases of grade A, 2 cases of grade B, 7 cases of grade C, 10 cases of grade D and 75 cases of grade E. The X-ray examination of all patients denoted that the bodies of injuryed vertebra were compressed and wedge-shaped, and the CT scan showed that 98 cases had spinal stenosis. After 2 weeeks and 3, 6, 12 months, the X-ray films were taken to evaluate bone graft fusion. The Cobb angle was measured. The recovery of nerve function was analyzed. Results The operation time was 55-180 minutes (mean 90 minutes) and the blood loss was 100-900 mL (mean 200 mL). All patients achieved heal ing by first intention with no compl ication. After operation, 93 cases were followed up for 6-15 months with an average of 11 months. Except for 11 patients who were at grade A before operation, one to two grade recover was observed in other patients. The average Cobb angle of injury segment was improved from preoperative 32.1° to postoperative 5.2°. The height of anterior border of injuried vertebral body was recovered from the preoperative average compressed remaining height 61.5% to postoperative 96.8%. The vestigial degree of canal is spinal is anteroposterior diameter was recovered from preoperative 65.7% to postoperative 89.9%. Imageology examination showed that all the patient achieved bone union within 6 months. The fusion rate of bone graft in spinal fusion was 100%. No loosening and breaking of nails occurred. Conclusion Pedicle fixators can restore and fix the thoracolumbar fractures, and the combination of autograft and allograft bone transplantation is a safe, rel iable and effective method.
ObjectiveTo investigate the security of pedicle screw fixation in fractured vertebra in treatment of thoracolumbar fractures by comparing with routine fixation cross fractured vertebra. MethodsA total of 101 cases of single segmental thoracolumbar fracture were selected between June 2008 and June 2011. Of them, 56 cases underwent pedicle screw fixation in fractured vertebra (group A), and 45 cases received routine fixation cross fractured vertebra (group B). There was no significant difference in gender, age, causes of injury, fracture type, fracture segment, Frankel grading, time of injury to operation, and the preoperative anterior vertebral height compression ratio and the canal occupation rate between 2 groups (P>0.05). There were 34 cases of junction fracture of pedicle and vertebra (type I), 2 cases of pedicle waist fracture (type Ⅱ), and 20 cases of junction fracture of pedicle and lamina (type Ⅲ) in group A. The position of fractured vertebral pedicle screw was observed; the anterior vertebral height compression ratio, canal occupation rate, and surgical complications were compared between 2 groups. ResultsA total of 103 pedicle screws were placed in 54 patients of group A, except 2 patients of type Ⅱ fracture; 96 screws were placed in the bone cortex completely and 7 screws deviated. The operation time of group A was significantly longer than that of group B (t=4.339, P=0.000), but there was no significant difference in intraoperative blood loss between 2 groups (t=-0.089, P=0.929). All 101 patients were followed up 6-16 months (mean, 8.5 months). The patients of 2 groups achieved nerve functional recovery. Fixation-related complications occurred in 1 case of 2 groups respectively, showing no significant difference (P=1.000). At last follow-up, according to Denis lumbago classification, 51 cases were rated as P1 level and 5 cases as P2 level in group A; 35 cases were rated as P1 level, 8 cases as P2 level, and 2 cases as P3 level in group B; and there was no significant difference between 2 groups (Z=-1.836, P=0.066). There was no significant difference between 2 groups in canal occupation rate at immediate after operation and at last follow-up (P>0.05), and in the anterior vertebral height compression ratio at immediate after operation (P>0.05), but the anterior vertebral height compression ratio of group B was significantly higher that of group A at last follow-up (P<0.05). ConclusionSingle segmental thoracolumbar fracture treated by pedicle screw fixation in fractured vertebra through posterior approach is safe and feasible according to different pedicle fracture types to guide fixation.