Bone cement enhanced pedicle screw fixation combined with vertebroplasty for elderly patients with malignant spinal tumors

Background Older patients with malignant spinal tumors are difficult to treat because they have many co-morbidities including osteoporosis. The purpose of this research is to discuss the technique and clinical outcome of bone cement enhanced pedicle screw fixation combined with vertebroplasty (the Sandwich Procedure) for elderly patients with severe osteoporosis and malignant spinal tumors. Methods This study includes 28 consecutive elderly patients with malignant thoracic or lumbar spinal tumors. There were nine patients with myelomas, and 19 patients with metastatic bone tumors. The Sandwich Procedure began with curettage of the tumor and a vertebroplasty with bone cement (polymethyl methacrylate, PMMA), followed by PMMA enhanced pedicle screw fixation. Patients were evaluated with the visual analogue scale (VAS), oswestry disability index (ODI), American Spinal Cord Injury Association (ASIA) neurological function classification, and the radiographic degree of kyphosis (Cobb angle). Data were analyzed using paired t-test to compare the pre- and post-operative values. The complications, local recurrences, and the survival status were also recorded. Results There was no operative mortality, and the mean operative time was 210 minutes (range 150-250 minutes). The average blood loss was 1550 ml (range 650-3300 ml). The average amount of cement for vertebroplasty was 3.6 ml (range 3-5 ml). The VAS, ODI, and ASIA scores were significantly improved after surgery (P<0.05). However, we found no differences between the pre and post-operative Cobb angles. The shortest survival time was 3 months, and we found no evidence of local recurrence in this group of patients. Conclusion The Sandwich Procedure is a safe operation and provides symptomatic relief in these difficult patients, permitting further treatment with chemotherapy or radiotherapy.