Objective: To explore the potential value of three-dimensional fast spin echo（3D-SPACE） combined with multilayer spiral CT （MSCT） in the diagnosis of knee cruciate ligament injury, to provide a new direction for the optimization of subsequent clinical diagnosis.
Methods: A total of 120 patients with knee cruciate ligament injury were treated from April 2020 to April 2021, aged from 21 to 68 with an average of（41.52±4.13） years old. For all patients, separate MSCT scanner scans, 3D-SPACE sequence scans alone and 3D-SPACE sequence combined with MSCT scans were used. The injury and classification of the anterior and posterior cruciate ligament of the knee were compared, the length of the anterior-medial bundle and posterolateral bundle and its angle of the knee with the horizontal plane were observed, the diagnostic value of 3 diagnostic methods in knee cruciate ligament injury were determined.
Results: There was no significant difference between the 3D-SPACE sequence scan alone and the MSCT test alone on the total diagnostic rate and grading total diagnostic rate（P>0.05）. The total diagnostic rate and grading total diagnostic rate of 3D-SPACE scan combined with MSCT were significantly higher than those of 3D-SPACE scan or MSCT alone（P<0.05）. The 3D-SPACE sequence scan alone and the MSCT detection alone had no significant difference in the measurement values related to the anterior and posterior cruciate ligaments of the knee joint（P>0.05）. 3D-SPACE sequence scanning combined with MSCT detection on the knee joint anterior and posterior cruciate ligament related measurements were significantly higher than the 3D-SPACE sequence scan or MSCT detection alone（P<0.05）. The area under the ROC curve estimated by 3D-SPACE sequence scanning combined with MSCT was 0.960, which was significantly higher than that of 3D-SPACE sequence scanning and MSCT alone evaluating the area under the ROC curve line of 0.756 and 0.795. The combined 3D-SPACE sequence scanning and 3D-SPACE sequence scanning MSCT analysis and prediction models were statistically different（Z=2.236, P<0.05）, and MSCT alone and 3D-SPACE sequence scanning combined with MSCT analysis and prediction models were statistically different（Z=2.653, P<0.05）.
Conclusion: The application of 3D-SPACE sequence combined with MSCT scanning for knee cruciate ligament injury can improve the diagnosis rate of patients with knee cruciate ligament injury.It can be used as a diagnostic tool for patients with knee cruciate ligament injury and is worthy of clinical application.
Keywords: Cruciate ligament; Diagnostic value; Knee joint; Ligament injury; Multislice spiral CT; Three-dimensional fast spin echo.