Clinical evaluation of the polymethylmethacrylate-augmented thoracic and lumbar pedicle screw fixation guided by the three-dimensional navigation for the osteoporosis patients.

PURPOSE: To evaluate the safety and efficacy of three-dimensional (3D) navigation-guided polymethylmethacrylate (PMMA)-augmented thoracic and lumbar pedicle screw fixation for the osteoporotic patients. METHODS: 27 consecutive osteoporosis patients with a variety of spinal disorders who underwent 3D navigation-guided PMMA-augmented pedicle screw fixation were evaluated clinically and radiologically in the perioperative and 1-year follow-up period. The improvement of Japanese Orthopaedic Association (JOA) scores was analyzed. PMMA leakage and other complications were inspected intraoperatively and postoperatively. Screw loosening and bone fusion were evaluated radiographically during follow-up. RESULTS: 8 patients had thoracic and lumbar fractures; 18 patients had degenerative spinal disorders; one patient had revision surgery. One patient died of postoperative pneumonia. Each of the other 26 patients was followed up regularly at 3, 6, 12 and 18 months postoperatively. The mean therapeutic improvement rate is 39.6% evaluated by JOA scores. 2 patients (7.4%) had leakage into the spinal canal in front of the posterior longitudinal ligament and two patients (7.4%) had leakage into the prevertebral soft tissue inspected by the postoperative CT scans. No pedicle cortex breach and cement leakage surrounding pedicle cortex were observed. None of patients complained of dyspnoea and showed evidence of pulmonary embolism. Bone fusions were found in 20 patients (bony fusion rate 76.9%) at the 12-month follow-up and no screw loosening occurs. CONCLUSION: The results show favorable outcome using 3D navigation-guided PMMA-augmented thoracic and lumbar pedicle screw fixation for the osteoporosis patients both clinically and radiologically.