The Presence of Cartilage Affects Femoral Rotational Alignment in Total Knee Arthroplasty

Yiming Yang; Xianli Zeng; Yan Jin; Zhemin Zhu; Tsung-Yuan Tsai; Jiarong Chen; Hongyuan Shen; Pingyue Li

doi:10.3389/fsurg.2022.802631

The Presence of Cartilage Affects Femoral Rotational Alignment in Total Knee Arthroplasty

Front Surg. 2022 Feb 16:9:802631. doi: 10.3389/fsurg.2022.802631. eCollection 2022.

Authors

Yiming Yang¹, Xianli Zeng¹, Yan Jin¹, Zhemin Zhu^{2

3

4}, Tsung-Yuan Tsai^{2

3

4}, Jiarong Chen¹, Hongyuan Shen¹, Pingyue Li¹

Affiliations

¹ Guangdong Key Lab of Orthopedic Technology and Implant, General Hospital of Southern Theater Command of PLA, The First School of Clinical Medicine, Southern Medical University, Guangzhou, China.
² Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
³ School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
⁴ Engineering Research Center of Clinical Translational Digital Medicine, Ministry of Education of PR China, Shanghai Jiao Tong University, Shanghai, China.

Abstract

Objective: To assess the difference between the posterior condylar angle (PCA) and the mechanical lateral distal femoral angle (mLDFA) in the osseous and cartilaginous contours in a non-arthritic Chinese population.

Methods: Computed tomography (CT) and magnetic resonance imaging (MRI) were obtained from 83 patients with knee injuries before arthroscopy, and femur and distal femoral cartilage three-dimensional (3D) models were constructed. The 3D cartilage model was arranged to share physical space with the 3D femoral model, and then PCA and mLDFA were measured on the osseous and cartilaginous contours, respectively. The differences between the measurements with and without cartilage were evaluated.

Results: The average PCA with cartilage was 2.88 ± 1.35° and without was 2.73 ± 1.34°. The difference was significant in all patients and females but not in males. The average mLDFA with cartilage was 84.73 ± 2.15° and without cartilage was 84.83 ± 2.26°, but the difference was statistically insignificant in all groups.

Conclusion: PCA on the osseous and cartilaginous contours significantly differed with and without cartilage in the female group, suggesting that cartilage thickness should be considered during preoperative femoral rotational resection planning.

Keywords: cartilage thickness; femoral alignment; mechanical lateral distal femoral angle; posterior condylar angle; preoperative planning; total knee arthroplasty.