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Erschienen in: Knee Surgery, Sports Traumatology, Arthroscopy 5/2020

21.06.2019 | KNEE

Classical target coronal alignment in high tibial osteotomy demonstrates validity in terms of knee kinematics and kinetics in a computer model

verfasst von: Shinichi Kuriyama, Mutsumi Watanabe, Shinichiro Nakamura, Kohei Nishitani, Kazuya Sekiguchi, Yoshihisa Tanaka, Hiromu Ito, Shuichi Matsuda

Erschienen in: Knee Surgery, Sports Traumatology, Arthroscopy | Ausgabe 5/2020

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Abstract

Purpose

The purpose of this study was to determine the ideal coronal alignment under dynamic conditions after open-wedge high tibial osteotomy (OWHTO). It was hypothesised that, although the classical target alignment was based on experimental evidence, it would demonstrate biomechanical validity.

Methods

Musculoskeletal computer models were analysed with various degrees of coronal correction in OWHTO during gait and squat, specifically with the mechanical axis passing through points at 40%, 50%, 60%, 62.5%, 70%, and 80% of the tibial plateau from the medial edge, defined as the weight-bearing line percentage (WBL%). The peak load on the lateral tibiofemoral (TF) joint, the medial collateral ligament (MCL), and anterior cruciate ligament (ACL) tensions, and knee kinematics with or without increased posterior tibial slope (PTS) were evaluated.

Results

The classical alignment with WBL62.5% achieved sufficient load on the lateral TF joint and maintained normal knee kinematics after OWHTO. However, over-correction with WBL80% caused an excessive lateral load and non-physiological kinematics. Increased WBL% resulted in increased MCL tension due to lateral femoral movement against the tibia. With WBL80%, abnormal contact between the medial femoral condyle and the medial intercondylar eminence of the tibia occurred at knee extension. The screw-home movement around knee extension and the TF rotational angle during flexion were reduced as WBL% increased. Increased PTS was associated with increased ACL tension and decreased TF rotation angle because of ligamentous imbalance.

Conclusions

The classical target alignment demonstrated validity in OWHTO, and over-correction should be avoided as it negatively impacts clinical outcome.

Level of evidence

IV.
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Metadaten
Titel
Classical target coronal alignment in high tibial osteotomy demonstrates validity in terms of knee kinematics and kinetics in a computer model
verfasst von
Shinichi Kuriyama
Mutsumi Watanabe
Shinichiro Nakamura
Kohei Nishitani
Kazuya Sekiguchi
Yoshihisa Tanaka
Hiromu Ito
Shuichi Matsuda
Publikationsdatum
21.06.2019
Verlag
Springer Berlin Heidelberg
Erschienen in
Knee Surgery, Sports Traumatology, Arthroscopy / Ausgabe 5/2020
Print ISSN: 0942-2056
Elektronische ISSN: 1433-7347
DOI
https://doi.org/10.1007/s00167-019-05575-3

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