Purpose: Clinical evidence indicates that an unintended increase in the medial proximal tibial angle (MPTA) can occur during slope-reducing tibial osteotomies, which is most relevant in anterior cruciate ligament (ACL) deficient knees. Therefore, the purpose of this three-dimensional (3D) simulation study is to assess how axial or coronal hinge axis rotation affect alignment parameters in anterior tibial closing wedge osteotomies (ACWO). The hypothesis states that a neutral hinge axis (NHA) in ACWO prevents changes in coronal and axial alignment.
Methods: A 3D surgical simulation was used to perform ACWO with a stepwise increment of one-degree (1°-5°) rotation around thirteen different hinge axes. Surface models were created from CT scans of 49 individuals (mean PTS 11.5° ± 3.8°) resulting in 3185 simulations. A NHA not changing the coronal or axial alignment was defined as oriented parallel to the posterior tibial plateau 1 cm underneath the articular surface. Anatomical landmarks were determined for each simulation to measure the PTS, MPTA, hip-knee-ankle angle (HKA), and tibial torsion (TT). The effects of the initial MPTA or PTS on the resulting alignment parameters and the effects of axial and sagittal rotation of the joint axis were analysed for their effects on postsimulation PTS, MPTA and TT.
Results: Clinically relevant hinge axis rotation in the coronal or axial plane below 20° did not significantly influence PTS correction ( > 0.05). Axial rotation of the hinge axis exceeding 10° led to significant MPTA changes (> +1.7° ± 0.03°) compared to the NHA ( < 0.001). Pre-simulation MPTA had no influence on post-simulation MPTA changes ( > 0.05).
Conclusion: NHA aligned parallel to the posterior tibial plateau below the articular surface prevents significant changes in MPTA during ATCWO. This 3D simulation suggest, that hinge axis orientation requires meticulous consideration during slope-reducing osteotomies to preserve alignment integrity.
Level Of Evidence: Level V, retrospective simulation study.
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http://dx.doi.org/10.1002/jeo2.70198 | DOI Listing |
J Exp Orthop
January 2025
Department Trauma Surgery BG Unfallklinik Murnau Murnau German.
Purpose: Clinical evidence indicates that an unintended increase in the medial proximal tibial angle (MPTA) can occur during slope-reducing tibial osteotomies, which is most relevant in anterior cruciate ligament (ACL) deficient knees. Therefore, the purpose of this three-dimensional (3D) simulation study is to assess how axial or coronal hinge axis rotation affect alignment parameters in anterior tibial closing wedge osteotomies (ACWO). The hypothesis states that a neutral hinge axis (NHA) in ACWO prevents changes in coronal and axial alignment.
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Departments of Medicine, Microbiology and Immunology, Biochemistry and Molecular Biology, and Pathology, State University of New York Upstate Medical University, Norton College of Medicine, 750 East Adams Street, Syracuse, NY 13210, USA. Electronic address:
The pathogenesis of autoimmunity is incompletely understood which limits the development of effective therapies. New compelling evidence indicates that the pentose phosphate pathway (PPP) profoundly regulate lineage development in the immune system that are influenced by genetic and environmental factors during metabolic stress underlying the development of autoimmunity. The PPP provides two unique metabolites, ribose 5-phosphate for nucleotide biosynthesis in support of cell proliferation and NADPH for protection against oxidative stress.
View Article and Find Full Text PDFbioRxiv
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Department of Population Health, University of Texas at Austin, Austin, TX.
Polygenic scores (PGSs) are being rapidly adopted for trait prediction in the clinic and beyond. PGSs are often thought of as capturing the direct genetic effect of one's genotype on their phenotype. However, because PGSs are constructed from population-level associations, they are influenced by factors other than direct genetic effects, including stratification, assortative mating, and dynastic effects ("SAD effects").
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!