The Posterior Condylar Cartilage Affects Rotational Alignment of the Femoral Component in Varus Knee Osteoarthritis

Daisuke Hamada; Keizo Wada; Hiroshi Mikami; Shunichi Toki; Tomohiro Goto; Takahiko Tsutsui; Tomoya Takasago; Akihiro Nagamachi; Koichi Sairyo

doi:10.2152/jmi.64.24

Originals

The Posterior Condylar Cartilage Affects Rotational Alignment of the Femoral Component in Varus Knee Osteoarthritis

Daisuke Hamada, Keizo Wada, Hiroshi Mikami, Shunichi Toki, Tomohiro Goto, Takahiko Tsutsui, Tomoya Takasago, Akihiro Nagamachi, Koichi Sairyo

Author information

Daisuke Hamada
Department of Orthopedics, Institute of Biomedical Sciences, University of Tokushima Graduate School
Keizo Wada
Department of Orthopedics, Institute of Biomedical Sciences, University of Tokushima Graduate School
Hiroshi Mikami
Department of Orthopedic Surgery, Yoshinogawa Medical Center
Shunichi Toki
Department of Orthopedic Surgery, Yoshinogawa Medical Center
Tomohiro Goto
Department of Orthopedics, Institute of Biomedical Sciences, University of Tokushima Graduate School
Takahiko Tsutsui
Department of Orthopedics, Institute of Biomedical Sciences, University of Tokushima Graduate School
Tomoya Takasago
Department of Orthopedics, Institute of Biomedical Sciences, University of Tokushima Graduate School
Akihiro Nagamachi
Department of Orthopedics, Institute of Biomedical Sciences, University of Tokushima Graduate School
Koichi Sairyo
Department of Orthopedics, Institute of Biomedical Sciences, University of Tokushima Graduate School

Keywords: Total knee arthroplasty, posterior condylar cartilage, condylar twist angle, navigation system, femoral rotation

JOURNAL FREE ACCESS

2017 Volume 64 Issue 1.2 Pages 24-29

DOI https://doi.org/10.2152/jmi.64.24

Details

Abstract

Rotational alignment of the femoral component in total knee arthroplasty (TKA) is important for patellar tracking and ligament balance. Preoperative planning based on radiography might have a potential risk for over-rotation because these X-ray based measurements can not detect asymmetric cartilage wear on posterior condyle. The purpose of this study is to evaluate the effect of the posterior condylar cartilage of varus osteoarthritic knee on rotational alignment of the femoral component in TKA. We established two different condylar twist angles (CTA) from intraoperative multiplanar reconstruction (MPR) images and intraoperative information of navigation system. The CTA measured by a navigation system that includes the cartilage (4.8±2.0°) was smaller than those measured by MPR images, which does not include the cartilage (6.6±2.1°) (p<0.05). The difference between these two angles that corresponds to the remaining posterior condylar cartilage was 1.7±1.2°. This result demonstrated that the posterior condylar cartilage might lead to over-rotational of the femoral component in varus osteoarthritic knee. Therefore, when determining rotational alignment of the femoral component, surgeons should consider the effect of the remaining posterior condylar cartilage to avoid the over-rotation of the femoral component, especially in severe varus knees. J. Med. Invest. 64: 24-29, February, 2016

Corresponding author

Register with J-STAGE for free!