Background: Achieving stable fixation when performing
tibiotalocalcaneal arthrodesis can be challenging, especially in osteopenic
bone. The purpose of the current investigation was to compare the stiffness
and fatigue endurance of blade-plate-and-screw fixation with intramedullary
rod fixation in a cadaveric model.
Methods: In ten matched pairs of fresh-frozen cadaveric legs, a
tibiotalocalcaneal arthrodesis was performed with use of a blade-plate and a
6.5-mm sagittal screw in one leg and with use of an intramedullary rod in the
contralateral leg. After an initial load-deformation curve was obtained, each
specimen was loaded to 270 N through 250,000 cycles at a rate of 3 Hz.
Results: Blade-plate-and-screw fixation resulted in significantly
higher mean initial and final stiffness and decreased plastic deformation than
did intramedullary rod fixation. In addition, there was an inverse correlation
between bone-mineral density and the difference in plastic deformation noted
between the specimens of each pair.
Conclusions: Blade-plate fixation is biomechanically superior to
intramedullary fixation for tibiotalocalcaneal arthrodesis.
Clinical Relevance: Although good fixation can be achieved with an
intramedullary rod or a blade-plate-and-screw construct, the stability of the
blade-plate-and-screw construct may have advantages, particularly in