Effects of incorporating kryptonite™ bone cement in fracture fixation with plating technique: A cadaveric study of humerus midshaft fracture

Abstract

Kryptonite™ bone cement has an opportunity to incorporate in plate/screw (PLT) technique of internal long bone fracture fixation. The effects of the bone cement as a bonding interface between plate and screw remain unknown mechanics. The purpose of this study was to compare biomechanical advantages of adding Kryptonite™ bone cement in non-locking screw vs. locking screw. The study was specifically addressed humerus midshaft fracture. The PLT technique in this study utilized Locking Compression Plate (LCP) which obtained mixed unicortical and bicortical screws. A total of 4 pairs of cadaveric humerus bone were randomly divided into two groups (n = 4). The Hybrid locking (HL) group contained locking unicortical screws whereas the hybrid non-locking group (HNK) utilized non-locking screws feature incorporating the biocompatibility cement in the constructed bone-implant. Biomechanical studies including static and dynamic tests were performed on the fixated specimens of the two groups to evaluate behavior of the bone implant in vivo condition, using servohydraulic testing system (MTS system) to obtain construct stiffness and rigidity for axial compression and torsion. Independent sample paired t-test was used to detect significant differences between the two groups with 95% confidence interval (p < 0.05). HNK group was found 27 and 20% higher than HL group in axial stiffness and yield strength respectively. Ultimate failure load of HNK group (1199 ± 232 N) is superior to the HL group (994 ± 239 N). The HNK group was found about 23.1% higher than HL group in torsional stiffness. The study was found statistically non-significant difference among the two groups. In conclusion, Kryptonite™ bone cement initially found to host both mechanical and biological advantages which become attractive for internal long bone fixation.