Hypothermic manipulation of bone cement can extend the handling time during vertebroplasty.
BACKGROUND
Polymethylmethacrylate (PMMA) is commonly used for clinical applications. However, the short handling time increases the probability of a surgeon missing the crucial period in which the cement maintains its ideal viscosity for a successful injection. The aim of this article was to illustrate the effects a reduction in temperature would have on the cement handling time during percutaneous vertebroplasty.


METHODS
The injectability of bone cement was assessed using a cement compressor. By twisting the compressor, the piston transmits its axial load to the plunger, which then pumps the bone cement out. The experiments were categorized based on the different types of hypothermic manipulation that were used. In group I (room temperature, sham group), the syringes were kept at 22°C after mixing the bone cement. In group 2 (precooling the bone cement and the container), the PMMA powder and liquid, as well as the beaker, spatula, and syringe, were stored in the refrigerator (4°C) overnight before mixing. In group 3 (ice bath cooling), the syringes were immediately submerged in ice water after mixing the bone cement at room temperature.


RESULTS
The average liquid time, paste time, and handling time were 5.1 ± 0.7, 3.4 ± 0.3, and 8.5 ± 0.8 min, respectively, for group 1; 9.4 ± 1.1, 5.8 ± 0.5, and 15.2 ± 1.2 min, respectively, for group 2; and 83.8 ± 5.2, 28.8 ± 6.9, and 112.5 ± 11.3 min, respectively, for group 3. The liquid and paste times could be increased through different cooling methods. In addition, the liquid time (i.e. waiting time) for ice bath cooling was longer than for that of the precooling method (p < 0.05).


CONCLUSIONS
Both precooling (i.e. lowering the initial temperature) and ice bath cooling (i.e. lowering the surrounding temperature) can effectively slow polymerization. Precooling is easy for clinical applications, while ice bath cooling might be more suitable for multiple-level vertebroplasty. Clinicians can take advantage of the improved injectability without any increased cost.
Graduate Institute of Medical Mechatronics, Department of Mechanical Engineering, Chang Gung University, Taoyuan, Taiwan.
Po-Liang
PL
Lai
Ching-Lung
CL
Tai
I-Ming
IM
Chu
Tsai-Sheng
TS
Fu
Lih-Huei
LH
Chen
Wen-Jer
WJ
Chen
D001843:Bone Cements / Q000138:chemical synthesis*; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D003080:Cold Temperature; D006801:Humans; D007035:Hypothermia / Q000601:surgery; D019904:Polymethyl Methacrylate / Q000008:administration & dosage / Q000138:chemical synthesis; D013997:Time Factors; D054854:Vertebroplasty / Q000295:instrumentation / Q000379:methods*
D001843:Bone Cements; D019904:Polymethyl Methacrylate