Temporal Changes in Reverse Torque of Locking-Head Screws Used in the Locking Plate in Segmental Tibial Defect in Goat Model

Frontiers in Surgery

Elizabeth G. Croy¹  Reza Seddighi¹  Richard C. Steiner¹  David E. Anderson¹  Rebecca E. Rifkin¹  Henry S. Adair¹  Pierre-Yves Mulon¹  Remigiusz M. Grzeskowiak² 

[1] Department of Large Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, Knoxville, TN, United States;null;

关键词: animal models;    segmental bone defect;    bone healing;    locking screws;    orthopedics;    biomechanics;    fracture fixation;   

DOI  :  10.3389/fsurg.2021.637268

来源: Frontiers

【 摘 要 】

The objective of this study was to evaluate changes in peak reverse torque (PRT) of the locking head screws that occur over time. A locking plate construct, consisting of an 8-hole locking plate and 8 locking screws, was used to stabilize a tibia segmental bone defect in a goat model. PRT was measured after periods of 3, 6, 9, and 12 months of ambulation. PRT for each screw was determined during plate removal. Statistical analysis revealed that after 6 months of loading, locking screws placed in position no. 4 had significantly less PRT as compared with screws placed in position no. 5 (p < 0.05). There were no statistically significant differences in PRT between groups as a factor of time (p > 0.05). Intracortical fractures occurred during the placement of 151 out of 664 screws (22.7%) and were significantly more common in the screw positions closest to the osteotomy (positions 4 and 5, p < 0.05). Periosteal and endosteal bone reactions and locking screw backout occurred significantly more often in the proximal bone segments (p < 0.05). Screw backout significantly, negatively influenced the PRT of the screws placed in positions no. 3, 4, and 5 (p < 0.05). The locking plate-screw constructs provided stable fixation of 2.5-cm segmental tibia defects in a goat animal model for up to 12 months.

【 授权许可】

CC BY