TY - JOUR
T1 - Mechanical strength of a new plate compared to six previously tested opening wedge high tibial osteotomy implants
AU - Diffo Kaze, Arnaud
AU - Maas, Stefan
AU - Belsey, James
AU - Hoffmann, Alexander
AU - Seil, Romain
AU - van Heerwaarden, Ronald
AU - Pape, Dietrich
N1 - Funding Information:
Arnaud Diffo Kaze, Stefan Maas, Dietrich Pape and Romain Seil are partners in the project “Experimentelle und klinische Orthopädie der Großregion / Orthopédie Expérimentale et Clinique de la Grande Région” from the Universität der Großregion / Université de la Grande Région (UGR), supported by the INTERREG IV Programme of the European Union.
Publisher Copyright:
© 2019, The Author(s).
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Background: This study aimed to assess the mechanical static and fatigue strength provided by the FlexitSystem plate in medial opening wedge high tibial osteotomies (MOWHTO), and to compare it to six previously tested implants: the TomoFix small stature, the TomoFix standard, the ContourLock, the iBalance, the second generation PEEKPower and the size 2 Activmotion. Thus, this will provide surgeons with data that will help in the choice of the most appropriate implant for MOWHTO. Methods: Six fourth-generation tibial bone composites underwent a MOWHTO and each was fixed using six FlexitSystem plates, according to standard techniques. The same testing procedure that has already been previously defined, used and published, was used to investigate the static and dynamic strength of the prepared bone-implant constructs. The test consisted of static loading and cyclical loading for fatigue testing. Results: During static testing, the group constituted by the FlexitSystem showed a fracture load higher than the physiological loading of slow walking (3.7 kN > 2.4 kN). Although this fracture load was relatively small compared to the average values for the other Implants from our previous studies, except for the TomoFix small stature and the Contour Lock. During fatigue testing, FlexitSystem group showed the smallest stiffness and higher lifespan than the TomoFix and the PEEKPower groups. Conclusions: The FlexitSystem plate showed sufficient strength for static loading, and average fatigue strength compared to the previously tested implants. Full body dynamic loading of the tibia after MOWHTO with the investigated implants should be avoided for at least 3 weeks. Implants with a wider T-shaped proximal end, positioned onto the antero-medial side of the tibia head, or inserted in the osteotomy opening in a closed-wedge construction, provided higher mechanical strength than implants with small a T-shaped proximal end, centred onto the medial side of the tibia head.
AB - Background: This study aimed to assess the mechanical static and fatigue strength provided by the FlexitSystem plate in medial opening wedge high tibial osteotomies (MOWHTO), and to compare it to six previously tested implants: the TomoFix small stature, the TomoFix standard, the ContourLock, the iBalance, the second generation PEEKPower and the size 2 Activmotion. Thus, this will provide surgeons with data that will help in the choice of the most appropriate implant for MOWHTO. Methods: Six fourth-generation tibial bone composites underwent a MOWHTO and each was fixed using six FlexitSystem plates, according to standard techniques. The same testing procedure that has already been previously defined, used and published, was used to investigate the static and dynamic strength of the prepared bone-implant constructs. The test consisted of static loading and cyclical loading for fatigue testing. Results: During static testing, the group constituted by the FlexitSystem showed a fracture load higher than the physiological loading of slow walking (3.7 kN > 2.4 kN). Although this fracture load was relatively small compared to the average values for the other Implants from our previous studies, except for the TomoFix small stature and the Contour Lock. During fatigue testing, FlexitSystem group showed the smallest stiffness and higher lifespan than the TomoFix and the PEEKPower groups. Conclusions: The FlexitSystem plate showed sufficient strength for static loading, and average fatigue strength compared to the previously tested implants. Full body dynamic loading of the tibia after MOWHTO with the investigated implants should be avoided for at least 3 weeks. Implants with a wider T-shaped proximal end, positioned onto the antero-medial side of the tibia head, or inserted in the osteotomy opening in a closed-wedge construction, provided higher mechanical strength than implants with small a T-shaped proximal end, centred onto the medial side of the tibia head.
KW - Activmotion
KW - Biomechanics
KW - ContourLock
KW - Correction angle
KW - Fatigue strength
KW - FlexitSystem
KW - High tibial osteotomy (HTO)
KW - Mechanical stiffness
KW - Osteoarthritis
KW - PEEKPower
KW - Permanent deformation
KW - Static strength
KW - TomoFix
KW - iBalance
UR - http://www.scopus.com/inward/record.url?scp=85074781382&partnerID=8YFLogxK
U2 - 10.1186/s40634-019-0209-1
DO - 10.1186/s40634-019-0209-1
M3 - Article
AN - SCOPUS:85074781382
SN - 2197-1153
VL - 6
JO - Journal of Experimental Orthopaedics
JF - Journal of Experimental Orthopaedics
IS - 1
M1 - 43
ER -