The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
Brigitte E. Scammell - One of the best experts on this subject based on the ideXlab platform.
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications.AimTo determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model.MethodsTwenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia.ResultsPlate integrity was retained up to 26 weeks on radiographs and scanning elec...
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need fo...
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications. Aim To determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model. Methods Twenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia. Results Plate integrity was retained up to 26 weeks on radiographs and scanning electron microscopy (SEM). The mechanical properties of the plated bones were equivalent or greater than the control bones at each time point although the relative improvement in mechanical properties diminished with time. Nano CT imaging and SEM revealed bone remodelling with cortical thinning beneath the composite plate which progressed as the duration of implantation increased. Discussion The bone-composite plate construct retained its mechanical properties compared to the control bone despite thinning of the cortex beneath the plate. More importantly, this work suggests that Fracture Fixation systems with equivalent mechanical properties to bone may still induce a “stress shielding” response.
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need for implant removal. Aim To determine the in vivo degradation profile of a novel phosphate glass fibre composite bioresorbable plate and effects on the underlying bone. Methods Twenty five NZW rabbits underwent application of the plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, nanoCT imaging, scanning electron microscopy (SEM) and mechanical testing of the plated bone and the opposite unplated tibia at each time point. Results At sacrifice, plate integrity was retained up to 12 weeks with no evidence of macroscopic inflammation. The mean load to failure of the plated bones expressed as a percentage of the opposite unplated bones was 179, 174, 172 and 115% after implantation for 2, 6, 12 and 26 weeks respectively. The flexural stiffness of the plated bones expressed as a percentage of the opposite bones revealed a mean increase of 245, 317, 205 and 110% at 2, 6, 12 and 26 weeks respectively. Although radiographs did not reveal any evidence of structural changes in the bones, NanoCT and SEM analysis revealed early porosity and progressive thinning of the cortex beneath the implant. However, bone formation around the plate progressed up to 26 weeks with improved cross sectional area characteristics of the plated bone compared to the control bone. Discussion Cortical changes beneath the plate would indicate that stress shielding may occur even in plates with similar mechanical characteristics to bone. However, this is only one part of the adaptive response of the bone which overall maintains the mechanical properties of the plated bone.
A. Qureshi - One of the best experts on this subject based on the ideXlab platform.
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications.AimTo determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model.MethodsTwenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia.ResultsPlate integrity was retained up to 26 weeks on radiographs and scanning elec...
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need fo...
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications. Aim To determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model. Methods Twenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia. Results Plate integrity was retained up to 26 weeks on radiographs and scanning electron microscopy (SEM). The mechanical properties of the plated bones were equivalent or greater than the control bones at each time point although the relative improvement in mechanical properties diminished with time. Nano CT imaging and SEM revealed bone remodelling with cortical thinning beneath the composite plate which progressed as the duration of implantation increased. Discussion The bone-composite plate construct retained its mechanical properties compared to the control bone despite thinning of the cortex beneath the plate. More importantly, this work suggests that Fracture Fixation systems with equivalent mechanical properties to bone may still induce a “stress shielding” response.
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need for implant removal. Aim To determine the in vivo degradation profile of a novel phosphate glass fibre composite bioresorbable plate and effects on the underlying bone. Methods Twenty five NZW rabbits underwent application of the plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, nanoCT imaging, scanning electron microscopy (SEM) and mechanical testing of the plated bone and the opposite unplated tibia at each time point. Results At sacrifice, plate integrity was retained up to 12 weeks with no evidence of macroscopic inflammation. The mean load to failure of the plated bones expressed as a percentage of the opposite unplated bones was 179, 174, 172 and 115% after implantation for 2, 6, 12 and 26 weeks respectively. The flexural stiffness of the plated bones expressed as a percentage of the opposite bones revealed a mean increase of 245, 317, 205 and 110% at 2, 6, 12 and 26 weeks respectively. Although radiographs did not reveal any evidence of structural changes in the bones, NanoCT and SEM analysis revealed early porosity and progressive thinning of the cortex beneath the implant. However, bone formation around the plate progressed up to 26 weeks with improved cross sectional area characteristics of the plated bone compared to the control bone. Discussion Cortical changes beneath the plate would indicate that stress shielding may occur even in plates with similar mechanical characteristics to bone. However, this is only one part of the adaptive response of the bone which overall maintains the mechanical properties of the plated bone.
Andrew J Parsons - One of the best experts on this subject based on the ideXlab platform.
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications.AimTo determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model.MethodsTwenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia.ResultsPlate integrity was retained up to 26 weeks on radiographs and scanning elec...
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need fo...
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications. Aim To determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model. Methods Twenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia. Results Plate integrity was retained up to 26 weeks on radiographs and scanning electron microscopy (SEM). The mechanical properties of the plated bones were equivalent or greater than the control bones at each time point although the relative improvement in mechanical properties diminished with time. Nano CT imaging and SEM revealed bone remodelling with cortical thinning beneath the composite plate which progressed as the duration of implantation increased. Discussion The bone-composite plate construct retained its mechanical properties compared to the control bone despite thinning of the cortex beneath the plate. More importantly, this work suggests that Fracture Fixation systems with equivalent mechanical properties to bone may still induce a “stress shielding” response.
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need for implant removal. Aim To determine the in vivo degradation profile of a novel phosphate glass fibre composite bioresorbable plate and effects on the underlying bone. Methods Twenty five NZW rabbits underwent application of the plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, nanoCT imaging, scanning electron microscopy (SEM) and mechanical testing of the plated bone and the opposite unplated tibia at each time point. Results At sacrifice, plate integrity was retained up to 12 weeks with no evidence of macroscopic inflammation. The mean load to failure of the plated bones expressed as a percentage of the opposite unplated bones was 179, 174, 172 and 115% after implantation for 2, 6, 12 and 26 weeks respectively. The flexural stiffness of the plated bones expressed as a percentage of the opposite bones revealed a mean increase of 245, 317, 205 and 110% at 2, 6, 12 and 26 weeks respectively. Although radiographs did not reveal any evidence of structural changes in the bones, NanoCT and SEM analysis revealed early porosity and progressive thinning of the cortex beneath the implant. However, bone formation around the plate progressed up to 26 weeks with improved cross sectional area characteristics of the plated bone compared to the control bone. Discussion Cortical changes beneath the plate would indicate that stress shielding may occur even in plates with similar mechanical characteristics to bone. However, this is only one part of the adaptive response of the bone which overall maintains the mechanical properties of the plated bone.
Ifty Ahmed - One of the best experts on this subject based on the ideXlab platform.
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications.AimTo determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model.MethodsTwenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia.ResultsPlate integrity was retained up to 26 weeks on radiographs and scanning elec...
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need fo...
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications. Aim To determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model. Methods Twenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia. Results Plate integrity was retained up to 26 weeks on radiographs and scanning electron microscopy (SEM). The mechanical properties of the plated bones were equivalent or greater than the control bones at each time point although the relative improvement in mechanical properties diminished with time. Nano CT imaging and SEM revealed bone remodelling with cortical thinning beneath the composite plate which progressed as the duration of implantation increased. Discussion The bone-composite plate construct retained its mechanical properties compared to the control bone despite thinning of the cortex beneath the plate. More importantly, this work suggests that Fracture Fixation systems with equivalent mechanical properties to bone may still induce a “stress shielding” response.
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need for implant removal. Aim To determine the in vivo degradation profile of a novel phosphate glass fibre composite bioresorbable plate and effects on the underlying bone. Methods Twenty five NZW rabbits underwent application of the plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, nanoCT imaging, scanning electron microscopy (SEM) and mechanical testing of the plated bone and the opposite unplated tibia at each time point. Results At sacrifice, plate integrity was retained up to 12 weeks with no evidence of macroscopic inflammation. The mean load to failure of the plated bones expressed as a percentage of the opposite unplated bones was 179, 174, 172 and 115% after implantation for 2, 6, 12 and 26 weeks respectively. The flexural stiffness of the plated bones expressed as a percentage of the opposite bones revealed a mean increase of 245, 317, 205 and 110% at 2, 6, 12 and 26 weeks respectively. Although radiographs did not reveal any evidence of structural changes in the bones, NanoCT and SEM analysis revealed early porosity and progressive thinning of the cortex beneath the implant. However, bone formation around the plate progressed up to 26 weeks with improved cross sectional area characteristics of the plated bone compared to the control bone. Discussion Cortical changes beneath the plate would indicate that stress shielding may occur even in plates with similar mechanical characteristics to bone. However, this is only one part of the adaptive response of the bone which overall maintains the mechanical properties of the plated bone.
C D Rudd - One of the best experts on this subject based on the ideXlab platform.
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications.AimTo determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model.MethodsTwenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia.ResultsPlate integrity was retained up to 26 weeks on radiographs and scanning elec...
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Orthopaedic Proceedings, 2018Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:BackgroundBioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need fo...
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the in vivo stress shielding response to a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar properties to bone thereby minimising the “stress shielding” associated with metal plates and obviating the need for implant removal. Phosphate glass fibre reinforced (PGF)-polylactic acid (PLA) composites are bioresorbable and have demonstrated sufficient retention of mechanical properties to enable load bearing applications. Aim To determine the potential in vivo “stress shielding” effects of a novel PGF reinforced PLA composite plate in an animal model. Methods Twenty five NZW rabbits underwent application of the composite plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, NanoCT imaging, histological assessment and mechanical testing of the retrieved plated tibia and opposite control tibia. Results Plate integrity was retained up to 26 weeks on radiographs and scanning electron microscopy (SEM). The mechanical properties of the plated bones were equivalent or greater than the control bones at each time point although the relative improvement in mechanical properties diminished with time. Nano CT imaging and SEM revealed bone remodelling with cortical thinning beneath the composite plate which progressed as the duration of implantation increased. Discussion The bone-composite plate construct retained its mechanical properties compared to the control bone despite thinning of the cortex beneath the plate. More importantly, this work suggests that Fracture Fixation systems with equivalent mechanical properties to bone may still induce a “stress shielding” response.
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the in vivo biocompatibility of a novel biodegradable Fracture Fixation Device
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: A. Qureshi, Andrew J Parsons, R G Pearson, Colin A Scotchford, C D Rudd, Ifty Ahmed, N Han, Brigitte E. ScammellAbstract:Background Bioresorbable materials offer the potential of developing Fracture Fixation plates with similar mechanical properties to bone thereby minimizing stress shielding and obviating the need for implant removal. Aim To determine the in vivo degradation profile of a novel phosphate glass fibre composite bioresorbable plate and effects on the underlying bone. Methods Twenty five NZW rabbits underwent application of the plate to the intact right tibia. They were divided into 5 groups corresponding to the time points from surgery to sacrifice −2, 6, 12, 26 and 52 weeks. Outcomes included radiographs, nanoCT imaging, scanning electron microscopy (SEM) and mechanical testing of the plated bone and the opposite unplated tibia at each time point. Results At sacrifice, plate integrity was retained up to 12 weeks with no evidence of macroscopic inflammation. The mean load to failure of the plated bones expressed as a percentage of the opposite unplated bones was 179, 174, 172 and 115% after implantation for 2, 6, 12 and 26 weeks respectively. The flexural stiffness of the plated bones expressed as a percentage of the opposite bones revealed a mean increase of 245, 317, 205 and 110% at 2, 6, 12 and 26 weeks respectively. Although radiographs did not reveal any evidence of structural changes in the bones, NanoCT and SEM analysis revealed early porosity and progressive thinning of the cortex beneath the implant. However, bone formation around the plate progressed up to 26 weeks with improved cross sectional area characteristics of the plated bone compared to the control bone. Discussion Cortical changes beneath the plate would indicate that stress shielding may occur even in plates with similar mechanical characteristics to bone. However, this is only one part of the adaptive response of the bone which overall maintains the mechanical properties of the plated bone.
