Response of fractured osteoporotic bone to polymethylacrylate after vertebroplasty: case report.

BACKGROUND CONTEXT: Polymethylmethacrylate (PMMA) is the most commonly used bone cement for vertebroplasties to treat osteoporotic vertebral compression fractures (VCFs). Several studies have described the reaction of normal bone to PMMA, but it is still unclear how fractured osteoporotic bone responds to PMMA.

PURPOSE: To describe the response of fractured osteoporotic bone to PMMA after vertebroplasty.

STUDY DESIGN/

SETTING

Case report.

METHODS

A 69-year-old woman with a previous vertebroplasty at T8 to treat an osteoporotic VCF was admitted to the hospital after she developed lower extremity motor weakness, diffuse hypoesthesia and decreased rectal tone. Magnetic resonance imaging studies of the thoracic spine showed that she had severe spinal cord compression at the level of T8 and T9, as well as akyphotic deformity. A corpectomy of T8 and T9 was performed as part of a spinal cord decompression procedure. Tissue from vertebral body T8, intervertebral discs T7-T8 and T8-T9 and the PMMA implant were then submitted for histologic evaluation.

RESULTS

Vertebral body T8 demonstrated viable bone trabeculae, osteoid. fibrosis, granulation tissue and multinucleated giant cells containing PMMA. Scattered necrotic bone fragments were identified throughout the vertebral body, most evident near the PMMA. PMMA leakage into the T7-T8 disc was identified without significant disc inflammation or necrosis.

CONCLUSION

Fractured osteoporotic bone is capable of undergoing a reparative healing response after vertebroplasty using PMMA.