Adding-on Fractures following Anterior Column Reconstruction in Treatment of Osteoporotic Post Traumatic Vertebral Collapse at the Thoraco-Lumbar Spine in 151 Patients with the Minimum 4 Year Follow-up

Summary: The purposes of this study are to investigate the fusion rates and the risks of the adding-on vertebral fractures above or below the anterior reconstruction of the osteoprotic posttraumatic vertebral collapse during the long-term follow-up. It became clear that as the fusion level increased, the risk of adding-on fractures increased. Steroid-induced osteoporosis is at a high risk of adding-on fracture after anterior reconstruction.

Introduction: The purposes of this study are to investigate the fusion rates and the risk of the adding-on vertebral fractures above or below the anterior reconstruction of the osteoporotic vertebral collapse during the long-term follow-up.

Methods: The total 151 (29 males and 122 females) patients who underwent anterior decompression and reconstruction of the anterior column support with the anterior instrumentation and the **ceramic vertebral spacer or the titanium cage at the thoracolumbar spine during January 1987 to December 2000. Their classification of osteoporosis were senile in 107 (70.9%), postmenopausal in 21 (13.9%),steroid induced in 16 (10.6%) and others in 7 (4.6%).All patients were followed-up more than 4 years.

Results: As to evaluation of spinal stabilization in total 151 patients, 132 patients undergone anterior fusion only had stable fusion in 117 (88.7%) and pseudoarthrosis (11.3%). Primary combined anterior and posterior fusion group in 19 patients had stable fusion in all. Pseudarthrosis of 15 patients was treated by posterior reinforcement in 14 and one did not have a salvage surgery. Adding-on vertebral fracture occurred in 35 (26.7%) of the 131 patients who underwent two level fusion and in 15 (75%) of 20 patients who underwent more than 2 level fusion during follow-up. Five of total 50 patients with adding-on fractures had to receive the salvage posterior long fusion. Patients with steroid-induced osteoporosis is at a high risk of adding-on fracture after anterior reconstruction. Deep sinking of the titanium cage might be one of the causes of the adding-on vertebral fracture due to increasing kyphosis.

FDA Disclosure Cleared: No ** A.W. Glass Ceramic Vertebral Spacer (not available at present)