| SUMMARY OF BACKGROUND DATA: For many surgeons, the anterior approach has become the optimal treatment for patients with compression of the spinal cord, whether it is caused by trauma, tumor or infection. When stabilization is needed, anterior fixation devices have been advocated for many years to avoid the additional approach required for posterior fixation. Early anterior devices presented both biomechanical and technical problems. During the past 2 decades, anterior thoracolumbar instrumentation has progressed significantly. Some new fixation systems have evolved to meet the anatomic, biomechanical, and imaging challenges. Many of these devices, however, have an unacceptably high rate of hardware failure. Recently, a new device for anterior thoracolumbar fixation—"Z" plate anterior thoracolumbar system was designed to solve some of the problems encountered with early anterior instrumentation, marketed with purported advantages in fatigue life and ease of use. OBJECTIVE: To study and evaluate characteristic of Z-plate and the medium/long-term clinical efficacy of anterior decompression, fusion and z-plate stabilization in treatment of fracture or tumor or tuberculosis of thoracolumbar spine.METHOD: This study consists of 53 patients in which 45 patients with spinal fracture, 7 patients with vertebral tumor and 1 patient with tuberculosis. Forty-nine patients underwent a one-stage direct anterolateral decompressive with sagittal reduction and corpectomy, autologous bone-graftingreconstruction and Z-plate stabilization procedure. In the four patients with malignant tumors, total spondylectomy was performed anteriorly, followed by implantation of hydroxyapatite cement and Z-plate stabilization. The study analyzed the clinical and radiologic results of all patients preoperative and postoperative. The percentage of the canal that was obstructed was measured on computed tomography. The cobb's angle in sagittal kyphosis and coronal scoliosis were measured in radiographs. Neurological functions of patients were measured with AISA Index, including a modification of the Grade scale of Frankel, Motor Index Score and Esthesia Index Score. Functions in daily activities were assessed with FIM Score. Complication of application of Z-plate was observed.RESULTS: Average estimated blood loss was 1769ml and average operation time was 268min. Average 35 min was spend in manipulating z-plate. Four patients were lost to follow-up, leaving 49 patients for detailed review. Subjects were followed up an average of 10.9 months (range: 3 to 34 months). Preoperative sagittal plane kyphotic deformity averaged 25.0 degree, while it was an average of 2.6 degree postoperatively. In coronal plane, deformity was improved from preoperative mean of 5.9 degree to a postoperative mean of 1.7 degree. Compression ratio of height was improved from a preoperative mean of 49.18% to a postoperative mean of 13.10% in injuries vertebral anterior border, and from a preoperative mean of 11.32% to a postoperative mean of 4.64% in injury vertebral posterior border.Distance(relative value) between upper and below vertebra adjacent injury vertebra , was improved from a preoperative mean of 116.96×10-2 to a postoperative mean of 143.48×10-2 in anterior border and from a preoperative mean of 118.72×10-2 to a postoperative mean of 139.51×10-2 in posterior border. Medullary canal compromise was an average value of 55.46% preoperatively and postoperatively it had an average value of 2.89%. Preoperative and posterior parametes of radiology had asignificant difference (P<0.01). Radiographs showed the unchanged positions of bone grafts and statistically insignificant loss of correction in the sagittal plane, which indicate successful bone fusion of the injured spinal segment. Ratio of bone fusion was 100%.After surgery, the neurological functions of 43 patients with neurologic deficits were improved by average 1.06 Frankel grade. The average Motor Index Score was improved from a preoperative mean of 25.68 score to a postoperative mean...
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