Introduction: Mechanical instability and axial load pain represent a major source of morbidity from pathologic fractures in the cancer population. In the absence of spinal cord compression, vertebral body cement augmentation and/or open surgical instrumentation have been shown to be viable treatment options. However, in our experience vertebral body cement augmentation alone may be inadequate when posterior elements are affected by tumor. In these cases, open surgical techniques may be an effective option but recent literature suggest multiple advantages to using MIS procedures in the non-cancer population including shorter recovery times, decreased hospitalization time and preservation of spinal musculature (1-9). Cement augmentation of the screw insertion sites has been shown to improve pull-out strength. We present five patients treated with cement augmented percutaneous pedicle screw placement (PPSP) for unstable pathologic fractures of the thoracolumbar spine.
Methods: Five patients underwent PPSP with cement augmentation for mechanical instability of the thoracolumbar spine caused by spinal metastases. None of the patient required a spinal canal decompression (10). All patients experienced movement-related back pain and mechanical radiculopathy and had spinal instability neoplastic scores (SINS) that were consistent with indeterminate instability or instability (11, 12). Pedicle screws were placed one level above and one level below the fracture. Patients were followed with serial x-rays and/or CT scans and VAS scores. Paired student t-test was used to measure the change in VAS.
Results: Three of five patients had complete resolution of VAS pain symptoms by two-week post-operative follow-up. The remaining two patients continued to have pain two weeks post-operatively but pain was substantially reduced (VAS 7.6 reduction, p<0.001). Median follow-up was 2.5 months (range 2-8 months), without major complications.
Conclusions: Cement augmented PPSP, represents a novel stabilization technique for patients with spinal metastases causing mechanical instability and provides significant pain relief.
Patient Care: Application of minimally invasive surgical techniques to cancer patients may improve quality of life for these patients.
Learning Objectives: By the completion of this session, participants should be able describe the roll for percutaneous pedicle screw placement with cement augmentation in the treatment of thoracolumbar fractures secondary to metastatic tumors.
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