Correlation of medial tibial slope and lateral tibial slope measured on radiographs and magnetic resonance imaging in patients with anterior cruciate ligament injury
Keng-Yi Lin1
, Cheng-Pang Yang2, Shang-Yu Yao1, Yu-Chieh Hung1, Shih-Feng Hung1, Yi-Jou Chen2, Chih-Hao Chiu2, Chin-Shan Ho3, Yi-Sheng Chan4
1Department of Orthopedic Surgery, Linkou Chang Gung Memorial Hospital, Taoyuan City, Taiwan
2Department of Orthopedic Surgery, Taoyuan General Hospital, Ministry of Health and Welfare, Taoyuan City, Taiwan
3National Taiwan Sport University, Graduate Institute of Sports Science, Taoyuan City, Taiwan
4Department of Orthopedic Surgery, Keelung Chang Gung Memorial Hospital, Keelung City, Taiwan
Keywords: Anterior cruciate ligament injury, correlation, lateral tibial slope, magnetic resonance imaging, medial tibial slope.
Abstract
Objectives: The study aimed to investigate the correlation between medial tibial slope (MTS) and lateral tibial slope (LTS) on magnetic resonance imaging (MRI), MTS measured by different imaging, and the intra- and interobserver reliability of measurements between reviewers with gaps of experience over 10 years.
Patients and methods: This retrospective study included 97 patients (93 males, 4 females; mean age: 30.8±8.3 years; range, 17 to 49 years) with anterior cruciate ligament (ACL) injuries who subsequently underwent double-bundle ACL reconstruction by a single surgeon between January 2005 and December 2014. The MTS was measured on lateral knee radiographs, and MTS and LTS were measured on MRIs. Three different reviewers, including a postgraduate year doctor, an orthopedic resident, and an attending orthopedic surgeon, performed the measurements. Each reviewer measured the slope of the same image three times. The correlations of MTS on radiographs and MTS/LTS on MRIs were calculated. Intra- and interobserver reliability were evaluated.
Results: The average MTS and LTS measured on MRI were not significantly different (6.4° and 6.9°, respectively; p=0.268) and exhibited a moderate positive correlation (r=0.544, p<0.001). The average MTS on radiographs was significantly greater than that on MRI (10.5° and 6.4°, respectively; p<0.001) with a low positive correlation (r=0.480, p<0.001). The intraobserver reliability of the postgraduate year doctor, the orthopedic resident, and the attending orthopedic surgeon were moderate to excellent. The interobserver reliability of MTS on radiographs was excellent (intraclass correlation coefficient [ICC]=0.925; p<0.001). The interobserver reliability of MTS on MRI as well as LTS on MRI was good (ICC=0.755 and 820, respectively; all p values <0.001).
Conclusion: Average MTS and LTS measured on MRI in patients with ACL injury exhibited a moderate positive correlation. The average MTS measured on radiographs was significantly greater than that on MRI with a low positive correlation.
Citation: Lin KY, Yang CP, Yao SY, Hung YC, Hung SF, Chen YJ, et al. Correlation of medial tibial slope and lateral tibial slope measured on radiographs and magnetic resonance imaging in patients with anterior cruciate ligament injury. Jt Dis Relat Surg 2024;35(3):504-512. doi: 10.52312/jdrs.2024.1558.
The study protocol was approved by the Chang Gung Medical Foundation Institutional Review Board (date: 12.09.2022, no: 202201347B0). The study was conducted in accordance with the principles of the Declaration of Helsinki.
A written informed consent was obtained from each patient.
Study conception and design, data collection, performing analysis; and writing the paper: K.Y.L.; Study conception and design data, collection: C.P.Y.; Data collection: S.Y.Y., Y.C.H., S.F.H., Y,J,C.; Study conception and design: C.H.C., C.S.H., Y.S.C.
The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.
The authors received no financial support for the research and/or authorship of this article.
The data that support the findings of this study are available from the corresponding author upon reasonable request.