Significance of dynamic mobility in restoring vertebral body height in vertebroplasty.

BACKGROUND AND PURPOSE: Many authors have reported the increase in vertebral body height after vertebroplasty. However, McKiernan et al demonstrated dynamic mobility in patients who underwent vertebroplasty and concluded that any article that claims vertebral height restoration must control for the dynamic mobility of fractured vertebrae. The purpose of this study was to compare prevertebroplasty (supine cross-table with a bolster beneath) with postvertebroplasty vertebral body height to find out whether vertebroplasty itself really increases the vertebral height. MATERIALS AND METHODS: From July 2005 to July 2010, 102 consecutive patients with 132 VCFs underwent vertebroplasty at our institution. The indications for vertebroplasty were severe pain that was not responsive to medical treatment, and MR imaging-confirmed edematous lesions. Prevertebroplasty (supine cross-table with bolster beneath) lateral radiographs were compared with postvertebroplasty radiographs to evaluate the height change in vertebroplasty. Kyphotic angle and anterior vertebral body height were measured. RESULTS: The patients ranged in age from 62 to 90 years. There were 16 men and 86 women. The difference in the kyphotic angle between supine cross-table with bolster and postvertebroplasty was -0.49 ± 3.59° (range, -9°-16°), which was not statistically significant (P = 0.124). The difference in the anterior vertebral body height between supine cross-table with bolster and postvertebroplasty was 0.84 ± 3.01 mm (range, -7.91-8.81 mm), which was statistically significant (P = .002). CONCLUSIONS: The restoration of vertebral body height in vertebroplasty seems to be mostly due to the dynamic mobility of fractured vertebrae; vertebroplasty itself does not contribute much to the restoration of vertebral height.

The value of dynamic radiographs in diagnosing painful vertebrae in osteoporotic compression fractures.

BACKGROUND AND PURPOSE: Many authors have reported the increase in vertebral body height after vertebroplasty; if the fractured vertebrae are mobile, we should be able to demonstrate their mobility in radiographs. The purpose of this study was to discover the diagnostic value of dynamic radiographs and the percentage of mobile vertebrae in painful VCFs. MATERIALS AND METHODS: From September 2005 to September 2008, 105 patients underwent surgery to treat 144 painful osteoporotic VCFs. The indications for surgery were severe pain and MR imaging-confirmed active edematous lesions. Preoperative sitting lateral radiographs of the fractured vertebrae were compared with supine cross-table (with a bolster beneath) lateral radiographs to determine the presence or absence of dynamic mobility. Kyphotic angle and anterior vertebral body height were measured. RESULTS: The patients' ages ranged from 62 to 90 years. There were 19 men and 86 women. The total number of mobile VCFs was 126 (87.5%). One hundred four (99%) patients had at least 1 mobile VCF. The average anterior vertebral height in sitting lateral radiographs was 13.53 ± 6.80 mm and increased to 22.01 ± 6.13 mm in supine cross-table with bolster lateral radiographs. The average vertebral body height increase was 8.48 ± 5.36 mm. CONCLUSIONS: Dynamic (sitting and supine with bolster) radiographs can be valuable in diagnosing painful vertebrae in VCFs. The sensitivity was 0.88 in this study.