Abstract
To investigate the effect of pressurizing vertebral bodies during vertebroplasty using different materials in the development of fat embolism (FE) and any associated cardiovascular changes.
Polymethylmethacrylate (PMMA) is the material of choice for vertebroplasty (VP). However, PMMA has several disadvantages such as exothermic curing, uncertain long-term biomechanical effects and biocompatibility. As a result alternative materials are being developed to overcome these problems.
In order to determine the role of PMMA in the generation of cardiovascular changes following vertebroplasty we compared injection of cement with wax in an animal model.
In twenty sheep, four vertebral bodies were augmented either with PMMA or bone wax. Heart rate, arterial, central venous and pulmonary artery pressure, cardiac output and blood gas values were recorded. At postmortem the lungs were subjected to histological evaluation.
The consecutive augmentation of four vertebral bodies with PMMA induced cumulative fat embolism causing significant deterioration of baseline mean arterial blood pressure (MABP) and blood gas values. Injection of bone wax resulted in similar cardiovascular changes and amount of intravascular fat in the lungs.
Conclusion: In this animal model cardiovascular complications during multiple VP happen regardless of the augmentation material used. The deteriorating baseline MABP during VP is associated with the pressurization and displacement of bone marrow/fat into the circulation rather than caused by polymethylmethacrylate.
The abstracts were prepared by Jean-Claude Theis. Correspondence should be addressed to him at Department of Orthopaedic Surgery, Dunedin Hospital, Private Bag 1921, Dunedin, New Zealand.
