Feasibility study of early prediction of postoperative MRI findings for knee stability after anterior cruciate ligament reconstruction

• Published in: BMC musculoskeletal disorders Vol. 22; no. 1; pp. 1 - 649
• Main Authors: Zhang, Jianqiang, Ma, Jiyao, Huang, Juan, Wang, Guoliang, Huang, Yilong, Li, Zhenhui, Yan, Jun, Zeng, Xiaomin, Zhu, Hongli, Zhao, Wei, Li, Yanlin, He, Bo
• Format: Journal Article
• Language: English
• Published: London BioMed Central Ltd 30.07.2021; BioMed Central; BMC
• Subjects: Anterior cruciate ligament; Anterior cruciate ligament (ACL) reconstruction; Arthritis; Biomechanics; Bone grafts; Bone imaging; Feasibility studies; Hypermobility; Injuries; Instability; Joint and ligament injuries; Joints; Knee; Magnetic resonance imaging; MRI findings early; Musculoskeletal diseases; Patients; Postoperative magnetic resonance (MR) examination; Predictions; Rehabilitation; Sports medicine; Stability of knee joint; Surgery; China
• ISSN: 1471-2474; 1471-2474
• DOI: 10.1186/s12891-021-04507-y

Abstract Background At present, the most effective and mature treatment after ACL injury and tear is ACL reconstruction, but the rehabilitation process after ACL reconstruction that is very long, so it is very important to find early MRI positive findings of knee instability. Methods We retrospectively collected the clinical and imaging data of 70 patients who underwent ACL reconstruction from January 2016 to December 2019; Based on clinical criteria, the patients were divided into a stable group ( n  = 57) and an unstable group ( n  = 13); We measured the MRI imaging evaluation indexes, including the position of the bone tunnel, graft status, and the anatomical factors; Statistical methods were used to compare the differences of imaging evaluation indexes between the two groups; The prediction equation was constructed and ROC curve was used to compare the prediction efficiency of independent prediction factors and prediction equation. Results There were significant differences in the abnormal position of tibial tunnel entrance, percentage of the position of tibial tunnel entrance, position of tibial tunnel exit, lateral tibial posterior slope (LTPS), width of intercondylar notch between stable knee joint group and unstable knee joint group after ACL reconstruction ( P  < 0.05); The position of tibial tunnel exits and the lateral tibial posterior slope (LTPS) and the sagittal obliquity of the graft were independent predictors among surgical factors and self-anatomical factors ( P  < 0.05); The prediction equation of postoperative knee stability was established: Logit(P) = -1.067–0.231*position of tibial tunnel exit + 0.509*lateral tibial posterior slope (LTPS)-2.105*sagittal obliquity of the graft; The prediction equation predicted that the AUC of knee instability was 0.915, the sensitivity was 84.6%, and the specificity was 91.2%. Conclusions We found that abnormalities of the position of the exit of the bone tunnel, lateral tibial posterior slope (LTPS) and sagittal obliquity of the graft were the early MRI positive findings of knee instability after ACL reconstruction. It is helpful for clinicians to predict the stability of knee joint after ACL reconstruction.