Abstract:

BACKGROUND: With the development of pedicle-screws, pedicle-screw internal fixation system has been widely used in the clinical treatment of thoracolumbar fractures because it can provide rigid internal fixation for injured spine to acquire more dimensional stabilization with little trauma and simple operation.
OBJECTIVE: To investigate the long-term therapeutic effects of CD2 pedicle-screw internal fixation in treatment of thoracolumbar burst fractures.
METHODS: A retrospective analysis was made on 72 cases of thoracolumbar burst fractures who received treatment at the Department of Orthopedics and Traumatology of Nantong University of Traditional Chinese Medicine between January 2000 and January 2008. All these patients received CD2 pedicle-screw internal fixation treatment. All of them were checked with radiography prior to and after surgery and at the final follow-up. The anterior and posterior vertebral body height, the situation of bone graft fusion, and the change of cobb angle were observed after surgery and at final follow-up. CT examination was performed in 27 cases prior to surgery and at the final follow-up to evaluate the space occupying in the spinal canal. Frankel classification was performed to evaluate the recovery of nerve system and Oswestry Disability Questionnaire was used to score the back pain at the final follow-up.
RESULTS AND CONCLUSION: 72 cases were followed up for an average of 48 months (range 0.5-8 years) after surgery. X-ray results showed that after surgery, the correction of anterior vertebral body height averaged 6.55 mm, posterior vertebral body height 2.69 mm, and cobb angle 25.7°, and at the final follow-up, correction loss averaged 2.29 mm in the anterior vertebral body height, 1.74 mm in the posterior vertebral body height, and 2.6° in the cobb angle. Among 27 patients scanned by CT, the space-occupying rate of the vertebral canal was 10%-75% prior to surgery and it was declined to 5%-24% at the final follow-up. In the last survery, eggshell phenomenon was still observed in 20 cases. Neurological status improved at least 1 Frankel grade in the patients who had preoperative incomplete paraplegia, while no improvement was obtained in those who had preoperative complete paraplegia. Clinical curative effects were evaluated according to Oswestry Disability Questionnaire, results showed 0% in 23 cases, 2% in 29 cases, 3% in 5 cases, 6% in 5 cases, 8% in 4 cases, 10% in 1 case，56% in 1 case, 57% in 1 case, 80% in 1 case, and 87% in 2 cases. Nuts loosened in 2 cases, pedicle screws loosened in 2 cases, and sticks broken in 1 case. All these findings indicate that CD2 pedicle-screw internal fixation in treatment of thoracolumbar burst fractures can well restore vertebral heights, physiologic curves, and neurological functions.