Biomechanical comparison of locking plate and crossing metallic and absorbable screws fixations for intra-articular calcaneal fractures

Abstract

The locking plate and percutaneous crossing metallic screws and crossing absorbable screws have been used clinically to treat intra-articular calcaneal fractures, but little is known about the biomechanical differences between them. This study compared the biomechanical stability of calcaneal fractures fixed using a locking plate and crossing screws. Three-dimensional finite-element models of intact and fractured calcanei were developed based on the CT images of a cadaveric sample. Surgeries were simulated on models of Sanders type III calcaneal fractures to produce accurate postoperative models fixed by the three implants. A vertical force was applied to the superior surface of the subtalar joint to simulate the stance phase of a walking gait. This model was validated by an in vitro experiment using the same calcaneal sample. The intact calcaneus showed greater stiffness than the fixation models. Of the three fixations, the locking plate produced the greatest stiffness and the highest von Mises stress peak. The micromotion of the fracture fixated with the locking plate was similar to that of the fracture fixated with the metallic screws but smaller than that fixated with the absorbable screws. Fixation with both plate and crossing screws can be used to treat intra-articular calcaneal fractures. In general, fixation with crossing metallic screws is preferable because it provides sufficient stability with less stress shielding.

Comparison of intramedullary nailing fixation and percutaneous locked plating fixation for the treatment of proximal tibial fractures: A meta-analysis

“…As for the PLP fixation method, higher stress on the locking plate could result in stress shielding of the fracture bones, which would delay healing due to the lack of mechanical stimulation. 30 In addition, plates were not routinely removed and require greater exposure and might affect periosteal blood supply. 31 Taken together, these factors were probably not conducive to the rapid healing of the fracture site.…”

Biomechanical Property of a Newly Designed Assembly Locking Compression Plate: Three-Dimensional Finite Element Analysis

“…The overall size of the element was 3 mm [8, 9]. The greatest curvature in the model was treated with Variable Grid Density Biased Sampling technology, and the grid density within the model was coarsened [10, 11]. Some important locations, such as contacts and constraints, were artificially divided to improve calculation accuracy.…”

Computational Biomechanical Analysis of Postoperative Calcaneal Fractures with Different Placement of the Sustentaculum Screw

“…Compared with the limitation of source shortage of specimens, and the inability to perform the research with different load conditions on cadaver specimens or physical models, the three‐dimensional (3‐D) finite element analysis (FEA) method has become one of the most effective approaches for biomechanical studies due to the rapid development of computer technology. As a reliable and effective computational biomechanical tool, FEA could be used to calculate the stress distribution, the contact area, and the displacement of the specific model. Ni et al .…”

“…As a reliable and effective computational biomechanical tool, FEA could be used to calculate the stress distribution, the contact area, and the displacement of the specific model. Ni et al . constructed a simplified finite element model of the calcaneus to assess the absorbable screw fixation for intra‐articular calcaneal fractures, including the Von Mises stress of the screws and the displacement of the calcaneus and screws.…”