title: [​Biomechanics of new implants for HTO].
abstract: Biomechanical characteristics of 5 tibial osteotomy plates for the treatment of medial knee joint osteoarthritis were examined. Fourth-generation tibial bone composites underwent a medial open-wedge high tibial osteotomy, using TomoFix™ standard, PEEKPower®, ContourLock®, TomoFix™ small stature plates, and iBalance® implants. Static compression load to failure and load-controlled cyclic fatigue failure tests were performed. All plates had sufficient stability up to 2400 N in the static compression load to failure tests. Screw breakage in the iBalance® group and opposite cortex fractures in all constructs occurred at lower loading conditions. The highest fatigue strength in terms of maximal load and number of cycles performed prior to failure was observed for the ContourLock® group followed by the iBalance® implants, the TomoFix™ standard and small stature plates. PEEKPower® had the lowest fatigue strength. All plates showed sufficient stability under static loading. Compared to the TomoFix™ and the PEEKPower® plates, the ContourLock® plate and iBalance® implant showed a higher mechanical fatigue strength during cyclic fatigue testing, suggesting that both mechanical static and fatigue strength increase with a wider proximal T‑shaped plate design together with diverging proximal screws. Mechanical strength of the bone-implant constructs decreases with a narrow T‑shaped proximal end design and converging proximal screws (TomoFix™) or a short vertical plate design (PEEKPower®). Published results indicate high fusion rates and good clinical results with the TomoFix™ plate, which is contrary to our findings. A certain amount of interfragmentary motion rather than high mechanical strength and stiffness seem to be important for bone healing which is outside the scope of this paper.
authors.affiliation: Orthopädische Klinik des Centre Hospitalier de Luxembourg, Akademisches Lehrkrankenhaus der Universitätskliniken des Saarlandes, 78, rue d'Eich, 1460, Luxembourg, Luxemburg. dietrichpape@yahoo.de.|Sports Medicine Research Laboratory, Luxembourg Institute of Health, Luxembourg, Centre Médical de la Fondation Norbert Metz, 76 rue d'Eich, 1460, Luxembourg, Luxemburg. dietrichpape@yahoo.de.
authors.forename: D
authors.initials: D
authors.lastname: Pape
authors.affiliation: Faculty of Science, Technology and Communication, University of Luxembourg, 6, rue R. Coudenhove-Kalergi, 1359, Luxembourg, Luxemburg.|Cartilage Net of the Greater Region, 66421, Homburg/Saar, Deutschland.
authors.forename: A
authors.initials: A
authors.lastname: Diffo Kaze
authors.affiliation: Orthopädische Klinik des Centre Hospitalier de Luxembourg, Akademisches Lehrkrankenhaus der Universitätskliniken des Saarlandes, 78, rue d'Eich, 1460, Luxembourg, Luxemburg.|Sports Medicine Research Laboratory, Luxembourg Institute of Health, Luxembourg, Centre Médical de la Fondation Norbert Metz, 76 rue d'Eich, 1460, Luxembourg, Luxemburg.
authors.forename: A
authors.initials: A
authors.lastname: Hoffmann
authors.affiliation: Faculty of Science, Technology and Communication, University of Luxembourg, 6, rue R. Coudenhove-Kalergi, 1359, Luxembourg, Luxemburg.|Cartilage Net of the Greater Region, 66421, Homburg/Saar, Deutschland.
authors.forename: S
authors.initials: S
authors.lastname: Maas
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology*; D001860:Bone Plates; D001863:Bone Screws; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery*; D010027:Osteotomy / Q000295:instrumentation*; D013977:Tibia / Q000601:surgery*; D016474:Weight-Bearing / Q000502:physiology*
keywords: Bone plates; High tibial osteotomy; Implant; Osteoarthritis; Tibial head