Therapeutic Efficacy of Vertebroplasty in Osteoporotic Vertebral Compression Fractures With Avascular Osteonecrosis A Minimum 2-Year Follow-up Study

Study Design. A retrospective review of clinical and radiological parameters. Objective. To assess for at least 2 years the radiological and clinical outcomes of patients who underwent polymethylmethacrylate (PMMA) vertebroplasty to treat osteoporotic vertebral compression fractures with avascular necrosis. Summary of Background Data. Recently, osteoporotic vertebral compression fractures with avascular osteonecrosis have been treated with percutaneous vertebroplasty. However, there have been no previous multiyear, clinical, and radiological studies of the results of vertebroplasty in the vertebral body with noninfected avascular osteonecrosis. Methods. Thirty patients were followed for at least 2 years after vertebroplasty. We retrospectively reviewed several parameters, including visual analogue scale score, Oswestry Disability Index, compression ratio, kyphotic angle, injection pattern of PMMA (interdigitation and solid mass), and morphological changes of the PMMA-cemented vertebral bodies. Results. The vertebral height and kyphotic angle were significantly corrected after vertebroplasty. However, the restored vertebral height recollapsed (P < 0.05), and the kyphotic angle became aggravated (P < 0.05) during the 2 years or longer of postoperative follow-up. Visual analogue scale and Oswestry Disability Index were significantly decreased at postoperative day 1. However, visual analogue scale and Oswestry Disability Index were significantly increased at 24 months postoperatively. There were 4 kinds of morphological changes of the injected PMMA-cemented vertebral body, including heterotopic ossification, fusion with the adjacent vertebral body, bone cement fragmentation and migration, and development of a radiolucent line around the PMMA mass in the vertebral body. Conclusion. After vertebroplasty, the compression and kyphosis of avascular necrotic vertebral bodies progressed continuously for 2 years or longer. Vertebroplasty may not provide sufficient stability. Therefore, we strongly recommend that strict observation and follow-up be used after vertebroplasty.