Impact of intraprosthetic drilling on the strength of the femoral stem in periprosthetic fractures: A finite element investigation

Research output: Contribution to journalArticleResearchpeer review

Authors

  • Stephan Brand
  • Michael Bauer
  • Maximilian Petri
  • Julian Schrader
  • Hans J. Maier
  • Christian Krettek
  • Thomas Hassel

Research Organisations

External Research Organisations

  • Hannover Medical School (MHH)
View graph of relations

Details

Original languageEnglish
Pages (from-to)675-681
Number of pages7
JournalProceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine
Volume230
Issue number7
Publication statusPublished - 6 May 2016

Abstract

Treatment of periprosthetic femur fractures after total hip arthroplasty remains a major challenge in orthopedic surgery. Recently, a novel surgical technique using intraprosthetic screw fixation has been suggested. The purpose of this study was to evaluate the influence of drilling the femoral hip stem on integrity and strength of the implant. The hypothesis was that intraprosthetic drilling and screw fixation would not cause the load limit of the prosthesis to be exceeded and that deformation would remain within the elastic limit. A sawbone model with a conventional straight hip stem was used and a Vancouver C periprosthetic fracture was created. The fracture was fixed with a nine-hole less invasive stabilization system plate with two screws drilled and inserted through the femoral hip stem. Three different finite element models were created using ANSYS software. The models increased in complexity including joint forces and stress risers from three different dimensions. A variation of drilling positions was analyzed. Due to the complexity of the physiological conditions in the human femur, the most complex finite element model provided the most realistic results. Overall, significant changes in the stresses to the prosthesis caused by the drilling procedure were observed. While the stresses at the site of the bore hole decreased, the load increased in the surrounding stem material. This effect is more pronounced and further the holes were apart, and it was found that increasing the number of holes could counteract this. The maximum load was still found to be in the area of the prosthesis neck. No stresses above the load limit of titanium alloy were detected. All deformations of the prosthesis stem remained in the elastic range. These results may indicate a potential role for intraprosthetic screw fixation in the future treatment of periprosthetic femur fractures.

Keywords

    ANSYS, Finite element analysis, intraprosthetic fixation

ASJC Scopus subject areas

Cite this

Impact of intraprosthetic drilling on the strength of the femoral stem in periprosthetic fractures: A finite element investigation. / Brand, Stephan; Bauer, Michael; Petri, Maximilian et al.
In: Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, Vol. 230, No. 7, 06.05.2016, p. 675-681.

Research output: Contribution to journalArticleResearchpeer review

Download
@article{24500ba6b15646efbd4850847173246e,
title = "Impact of intraprosthetic drilling on the strength of the femoral stem in periprosthetic fractures: A finite element investigation",
abstract = "Treatment of periprosthetic femur fractures after total hip arthroplasty remains a major challenge in orthopedic surgery. Recently, a novel surgical technique using intraprosthetic screw fixation has been suggested. The purpose of this study was to evaluate the influence of drilling the femoral hip stem on integrity and strength of the implant. The hypothesis was that intraprosthetic drilling and screw fixation would not cause the load limit of the prosthesis to be exceeded and that deformation would remain within the elastic limit. A sawbone model with a conventional straight hip stem was used and a Vancouver C periprosthetic fracture was created. The fracture was fixed with a nine-hole less invasive stabilization system plate with two screws drilled and inserted through the femoral hip stem. Three different finite element models were created using ANSYS software. The models increased in complexity including joint forces and stress risers from three different dimensions. A variation of drilling positions was analyzed. Due to the complexity of the physiological conditions in the human femur, the most complex finite element model provided the most realistic results. Overall, significant changes in the stresses to the prosthesis caused by the drilling procedure were observed. While the stresses at the site of the bore hole decreased, the load increased in the surrounding stem material. This effect is more pronounced and further the holes were apart, and it was found that increasing the number of holes could counteract this. The maximum load was still found to be in the area of the prosthesis neck. No stresses above the load limit of titanium alloy were detected. All deformations of the prosthesis stem remained in the elastic range. These results may indicate a potential role for intraprosthetic screw fixation in the future treatment of periprosthetic femur fractures.",
keywords = "ANSYS, Finite element analysis, intraprosthetic fixation",
author = "Stephan Brand and Michael Bauer and Maximilian Petri and Julian Schrader and Maier, {Hans J.} and Christian Krettek and Thomas Hassel",
year = "2016",
month = may,
day = "6",
doi = "10.1177/0954411916647078",
language = "English",
volume = "230",
pages = "675--681",
journal = "Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine",
issn = "0954-4119",
publisher = "Mechanical Engineering Publications Ltd.",
number = "7",

}

Download

TY - JOUR

T1 - Impact of intraprosthetic drilling on the strength of the femoral stem in periprosthetic fractures

T2 - A finite element investigation

AU - Brand, Stephan

AU - Bauer, Michael

AU - Petri, Maximilian

AU - Schrader, Julian

AU - Maier, Hans J.

AU - Krettek, Christian

AU - Hassel, Thomas

PY - 2016/5/6

Y1 - 2016/5/6

N2 - Treatment of periprosthetic femur fractures after total hip arthroplasty remains a major challenge in orthopedic surgery. Recently, a novel surgical technique using intraprosthetic screw fixation has been suggested. The purpose of this study was to evaluate the influence of drilling the femoral hip stem on integrity and strength of the implant. The hypothesis was that intraprosthetic drilling and screw fixation would not cause the load limit of the prosthesis to be exceeded and that deformation would remain within the elastic limit. A sawbone model with a conventional straight hip stem was used and a Vancouver C periprosthetic fracture was created. The fracture was fixed with a nine-hole less invasive stabilization system plate with two screws drilled and inserted through the femoral hip stem. Three different finite element models were created using ANSYS software. The models increased in complexity including joint forces and stress risers from three different dimensions. A variation of drilling positions was analyzed. Due to the complexity of the physiological conditions in the human femur, the most complex finite element model provided the most realistic results. Overall, significant changes in the stresses to the prosthesis caused by the drilling procedure were observed. While the stresses at the site of the bore hole decreased, the load increased in the surrounding stem material. This effect is more pronounced and further the holes were apart, and it was found that increasing the number of holes could counteract this. The maximum load was still found to be in the area of the prosthesis neck. No stresses above the load limit of titanium alloy were detected. All deformations of the prosthesis stem remained in the elastic range. These results may indicate a potential role for intraprosthetic screw fixation in the future treatment of periprosthetic femur fractures.

AB - Treatment of periprosthetic femur fractures after total hip arthroplasty remains a major challenge in orthopedic surgery. Recently, a novel surgical technique using intraprosthetic screw fixation has been suggested. The purpose of this study was to evaluate the influence of drilling the femoral hip stem on integrity and strength of the implant. The hypothesis was that intraprosthetic drilling and screw fixation would not cause the load limit of the prosthesis to be exceeded and that deformation would remain within the elastic limit. A sawbone model with a conventional straight hip stem was used and a Vancouver C periprosthetic fracture was created. The fracture was fixed with a nine-hole less invasive stabilization system plate with two screws drilled and inserted through the femoral hip stem. Three different finite element models were created using ANSYS software. The models increased in complexity including joint forces and stress risers from three different dimensions. A variation of drilling positions was analyzed. Due to the complexity of the physiological conditions in the human femur, the most complex finite element model provided the most realistic results. Overall, significant changes in the stresses to the prosthesis caused by the drilling procedure were observed. While the stresses at the site of the bore hole decreased, the load increased in the surrounding stem material. This effect is more pronounced and further the holes were apart, and it was found that increasing the number of holes could counteract this. The maximum load was still found to be in the area of the prosthesis neck. No stresses above the load limit of titanium alloy were detected. All deformations of the prosthesis stem remained in the elastic range. These results may indicate a potential role for intraprosthetic screw fixation in the future treatment of periprosthetic femur fractures.

KW - ANSYS

KW - Finite element analysis

KW - intraprosthetic fixation

UR - http://www.scopus.com/inward/record.url?scp=84973532349&partnerID=8YFLogxK

U2 - 10.1177/0954411916647078

DO - 10.1177/0954411916647078

M3 - Article

C2 - 27272200

AN - SCOPUS:84973532349

VL - 230

SP - 675

EP - 681

JO - Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine

JF - Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine

SN - 0954-4119

IS - 7

ER -

By the same author(s)