Three-Dimensional Osseointegration Patterns of Cementless Femoral Stems: An ex Vivo Study with High-Resolution Imaging and Histological Evaluation.

Autor:	Schwarz GM; Department of Orthopedics and Trauma-Surgery, Medical University of Vienna, Vienna, Austria.; Center for Anatomy and Cell Biology, Medical University Vienna, Vienna, Austria.; Michael Ogon Laboratory for Orthopedic Research, Orthopedic Hospital Vienna, Vienna, Austria., Synek A; Institute for Lightweight Design and Structural Biomechanics, Technical University of Vienna, Austria., Senck S; Research Group Computed Tomography, University of Applied Sciences Upper Austria, Wels, Austria., Kandathil SA; Center for Anatomy and Cell Biology, Medical University Vienna, Vienna, Austria., Holzleitner M; Research Group Computed Tomography, University of Applied Sciences Upper Austria, Wels, Austria., Trieb K; Department of Orthopaedic and Trauma Surgery, Paracelsus Medical University Salzburg, Salzburg, Austria., Huber S; Center for Anatomy and Cell Biology, Medical University Vienna, Vienna, Austria.; Michael Ogon Laboratory for Orthopedic Research, Orthopedic Hospital Vienna, Vienna, Austria., Pahr D; Institute for Lightweight Design and Structural Biomechanics, Technical University of Vienna, Austria.; Division Biomechanics, Karl Landsteiner University of Health Sciences, Krems an der Donau, Austria., Hofstaetter JG; Michael Ogon Laboratory for Orthopedic Research, Orthopedic Hospital Vienna, Vienna, Austria.; 2nd Department, Orthopaedic Hospital Vienna Speising, Vienna, Austria., Hirtler L; Center for Anatomy and Cell Biology, Medical University Vienna, Vienna, Austria.
Jazyk:	angličtina
Zdroj:	The Journal of bone and joint surgery. American volume [J Bone Joint Surg Am] 2024 Jun 05; Vol. 106 (11), pp. 941-949. Date of Electronic Publication: 2024 Mar 21.
DOI:	10.2106/JBJS.23.00526
Abstrakt:	Background: Osseointegration is essential for the long-term survival of cementless femoral stems and is dependent on periprosthetic bone quality and correct implantation technique. The aim of this study was to evaluate the 3-dimensional long-term fixation patterns of, and bone microarchitecture around, cementless hip stems. Methods: Four specimens with varying degrees of bone quality and fixation characteristics from body donors who had received Alloclassic Zweymüller hip stems during their lifetime (mean time in situ at the time of death: 12.73 years) were evaluated with use of radiographs, high-resolution computed tomography (CT) scans, and hard-tissue histology. The CT voxel size was 85 µm, and the following parameters were calculated: total bone volume, total bone volume fraction, trabecular bone volume, trabecular bone volume fraction, cortical bone volume, cortical bone volume fraction, and cortical thickness. Bone-implant contact and canal fill index values for each Gruen zone of the specimens were calculated with use of histological samples. Results: Femoral stems with apparently good cortical contact on clinical radiographs showed higher values for cortical bone volume, trabecular bone volume, and cortical thickness in the high-resolution CT analysis than femoral stems with apparently weak cortical contact on clinical radiographs. Based on the histological evaluation, the mean bone-implant contact ranged from 22.94% to 57.24% and the mean canal fill index ranged from 52.33% to 69.67% among the specimens. Conclusions: This study demonstrated different osseointegration patterns of cementless femoral stems on the basis of radiographs, high-resolution CT scans, and histological evaluation. Femora with high cortical bone volume and cortical thickness were associated with higher canal fill indices, whereas femora with low cortical bone volume and cortical thickness had lower canal fill indices and showed a characteristic corner-anchorage pattern. Clinical Relevance: Osseointegration patterns and thus the long-term survival of cementless femoral stems are dependent on cortical bone volume and cortical thickness. Competing Interests: Disclosure: Part of this work was supported by the project entitled “TIMed 2022++ - Technological Innovation in Medicine 2022++”, which is funded by the Regional Government of Upper Austria. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H947 ). (Copyright © 2024 by The Journal of Bone and Joint Surgery, Incorporated.)
Databáze:	MEDLINE
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