Abstract
Objective The aim of the study was to compare the stiffness and cyclic fatigue of locking compression
plate constructs from three manufacturers, DePuy Synthes (DPS), Knight Benedikt (KB),
and Provet Veterinary Instrumentation (Vi), under cyclic torsion.
Methods The constructs of DPS, KB, and Vi were assembled by fixing a 10-hole 3.5-mm stainless
steel locking compression plate 1 mm away from a validated bone model with a fracture
gap of 47 mm. The corresponding drill guides and locking screws were used. Three groups
of six constructs were tested in cyclic torsion until failure.
Results There was no significant difference in initial stiffness between DPS constructs (28.83 ± 0.84
N·m/rad) and KB constructs (28.38 ± 0.81 N·m/rad), and between KB constructs and Vi
constructs (27.48 ± 0.37 N·m/rad), but the DPS constructs were significantly stiffer
than the Vi constructs. The DPS constructs sustained the significantly highest number
of cycles (24,833 ± 2,317 cycles) compared with KB constructs (16,167 ± 1,472 cycles)
and Vi constructs (19,833 ± 4,792 cycles), but the difference between KB and Vi constructs
was not significant. All constructs failed by screw damage at the shaft between the
plate and the bone model.
Conclusion DPS constructs showed superior initial torsional stiffness and cyclic fatigue life
than Vi constructs, whereas KB and Vi constructs shared comparable results. Further
investigation is required to assess the clinical significance of these biomechanical
differences.
Keywords
locking plate - cyclic loading - torsion - fatigue life - biomechanical performance
of implants
