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Minerva Ortopedica e Traumatologica 2002 September;53(3):151-6

Copyright © 2002 EDIZIONI MINERVA MEDICA

language: Italian

The role of hydroxyapatite in improving pin stability and decreasing risk of infection

Moroni A., Vannini F., Romagnoli M., Pegreffi F., Giannini S.

The purpose of this manuscript is to review the techniques for optimizing the interface between the bone and pin to minimize pin mobilization and infection. The recent literature on bone-pin fixation improvement is reviewed. This paper reports different materials and methods described by various authors and their results. Among the different techniques to improve bone-pin fixation, coating the pins with hydroxyapatite (HA) proved to be the most effective. Three groups of seven patients had external fixation of mid-diaphyseal tibial fractures using uncoated pins, uncoated bicylindrical pins, and hydroxyapatite-coated bicylindrical pins, respectively. All fractures were fixed with six pins, and all fractures united. Both types of stainless steel pins showed a lower extraction torque than insertion torque in all cases, whereas the mean extraction torque in the hydroxyapatite coated pins was unchanged. In a clinical study evaluating bone-pin interface, at 10,000 times magnification direct bone pin contact was found only in hydroxyapatite-coated pins. These studies show that in hydroxyapatite-coated pins there is no deterioration of the bone-pin interface strength and there is optimal bone-pin contact.