Year-end Sale % OFF 
Abstract
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.
Highlights
Animal models are commonly used in bone healing studies and the choice of animal models is vital to ensure valid results of the study [1,2,3,4,5,6,7,8,9]
Segmental bone defects of the tibia in goats have been wellestablished as a bone healing model in orthopedic translational studies [3,4,5,6,7,8,9]
The mean peak reverse torque (PRT) measured 3, 6, 9 and 12 months after surgery equaled 195.78 ± 32.9 Ncm, 158.48 ± 52.9 Ncm, 153.48 ± 24.0 Ncm, and 134.69 ± 17.1 Ncm, respectively; no statistically significant differences were found between the treatment groups as well no statistically significant correlation was found between PRT and time (p > 0.05; Table 1)
Summary
Animal models are commonly used in bone healing studies and the choice of animal models is vital to ensure valid results of the study [1,2,3,4,5,6,7,8,9]. Important considerations for bone research include animal species, age, target bone, size of the defect, bone structure and vascularization, presence of periosteum, length of the study period, mechanical loads and stresses on the limb, and fixation methods [8, 9]. Implants, such as bone fillers designated for use in orthopedics, should be tested in appropriate sites, such as the long bones, so that relevant biomechanical forces are exerted on the devices and that the device is exposed to the target environment [9]. Despite the advantages of these internal fixation devices, studies describing and evaluating the locking plates as the stabilization technique for segmental defects as well as looking at the longterm implant integration are lacking
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
