Biomechanical evaluation of a new bone cement for use in vertebroplasty.

Abstract

STUDY DESIGN:

Comparative ex vivobiomechanical study.

OBJECTIVES:

To determine the strength and stiffness of osteoporotic vertebral bodies subjected to compression fractures and subsequently stabilized via bipedicular injection of one of two bone cements: one is a commercially available polymethylmethacrylate (Simplex P) and one is a proprietary glass-ceramic-reinforced BisGMA/BisEMA/TEGDMA matrix composite that is being developed for use in vertebroplasty (Orthocomp).

SUMMARY OF BACKGROUND DATA:

Osteoporotic compression fractures present diagnostic and therapeutic challenges for the clinician. Vertebroplasty, a new technique for treating such fractures, stabilizes vertebral bodies by injection of cement. Little is known, however, about the biomechanics of this treatment.

METHODS:

Five vertebral bodies (L1-L5) from each of four fresh spines were harvested from female cadavers (age, 80 +/- 5 years), screened for bone density using DEXA (t = -3.4 to -6.4), disarticulated, and compressed in a materials testing machine to determine initial strength and stiffness. The fractures then were repaired using a transpedicular injection of either Orthocomp or Simplex P and recrushed.

RESULTS:

For both cement treatments, vertebral body strength after injection of cement was significantly greater than initial strength values. Vertebral bodies augmented with Orthocomp recovered their initial stiffness; however, vertebral bodies augmented with Simplex P were significantly less stiff than they were in their initial condition.

CONCLUSIONS:

Augmentation with Orthocomp results in similar or greater mechanical properties compared with Simplex P, but these biomechanical results have yet to be substantiated in clinical studies.

• Authors: S M Belkoff, J M Mathis, E M Erbe, D C Fenton
• Journal: Spine (Spine (Phila Pa 1976)) Vol. 25 Issue 9 Pg. 1061-4 (May 01 2000) ISSN: 0362-2436 [Print] United States
• PMID: 10788848 (Publication Type: Journal Article)

Chemical References

• Biocompatible Materials
• Bone Cements
• Methylmethacrylate

Topics

• Aged
• Aged, 80 and over
• Analysis of Variance
• Biocompatible Materials (therapeutic use)
• Biomechanical Phenomena
• Bone Cements (therapeutic use)
• Female
• Humans
• Lumbar Vertebrae (injuries, surgery)
• Methylmethacrylate (therapeutic use)
• Osteoporosis (surgery)
• Spinal Fractures (surgery)