Height gain of vertebral bodies and stabilization of vertebral geometry over one year after vertebroplasty of osteoporotic vertebral fractures

Abstract

The height gain of vertebral bodies after vertebroplasty and geometrical stability was evaluated over a one-year period. Osteoporotic fractures were treated with vertebroplasty. The vertebral geometry and disc spaces were analysed using reformatted computed tomography (CT) images: heights of the anterior, posterior, and lateral vertebral walls, disc spaces, endplate angles, and minimal endplate distances. Vertebrae were assigned to group I [severe compression (anterior height/posterior height) <0.75] and group II (moderate compression index >0.75). A total of 102 vertebral bodies in 40 patients (12 men, 28 women, age 70.3 +/- 9.5) were treated with vertebroplasty and prospectively followed for 12 months. Group I showed a greater benefit compared with group II with respect to anterior height gain (+2.1 +/- 1.9 vs +0.7 +/- 1.6 mm, P < 0.001), reduction of endplate angle (-3.6 +/- 4.2 vs -0.8 +/- 2.3 degrees , P < 0.001), and compression index (+0.09 +/- 0.11 vs +0.01 +/- 0.06, P < 0.001). At one-year follow-up, group I demonstrated preserved anterior height gain (+1.5 +/- 2.8 mm, P < 0.015) and improved endplate angle (-3.4 +/- 4.9 degrees , P < 0.001). In group II, the vertebral heights returned to and were fixed at the pre-interventional levels. Vertebroplasty provided vertebral height gain over one year, particularly in cases with severe compression. Vertebrae with moderate compression were fixed and stabilized at the pre-treatment level over one year.

Risk factors for the development of vertebral fractures after percutaneous vertebroplasty

“…(16,31) Such leaks might occur through fractured endplates or vacuum clefts or may result from iatrogenic endplate perforations with the needle tip. (32) The hard cement into the disk probably alters the load transfer increasing the mechanical pressure of the endplate of the adjacent vertebral body, increasing the risk of a VF in osteoporotic vertebrae. (33) In addition, the asymmetrical distribution of the cement contributes to the alteration in the biomechanics of the vertebra.…”

“…Cement leakage into the disk has been previously associated with adjacent VF after VP . Such leaks might occur through fractured endplates or vacuum clefts or may result from iatrogenic endplate perforations with the needle tip . The hard cement into the disk probably alters the load transfer increasing the mechanical pressure of the endplate of the adjacent vertebral body, increasing the risk of a VF in osteoporotic vertebrae .…”

Vertebroplasty and kyphoplasty update

“…It is intuitive that this could prevent or treat kyphosis, avoid gastrointestinal complications associated with spinal deformity, and maintain pulmonary function. Although improvement in kyphosis has been reported [ 42 ], the longterm clinical benefi ts of vertebral height restoration have not been clearly demonstrated, and vertebroplasty, as well as kyphoplasty, has now been shown to restore lost vertebral height in some patients [ 43 ]. McKiernan et al [ 44 ] demonstrated "dynamic mobility" (positional changes in the height of fractured vertebral bodies) in 44% of 41 consecutive patients undergoing vertebroplasty, as well as some restoration of lost vertebral height in these patients.…”

An improved metric for quantifying the stiffnesses of intact human vertebrae

“…Vertebral augmentation is a common treatment for restoring the geometry and mechanical competence of vertebrae affected by severe osteoporosis [1][2][3][4][5] or metastatic involvement [6][7][8][9][10]. Vertebroplasty technology is developing rapidly, with one facet of the new technology focused on developing new protocols that restore the vertebra to its pre-disease stiffness [11][12][13][14].…”