| Objective: To investigate the relationship between traumatic bone marrow abnormalities and the mechanism of trauma and soft tissue injury in adolescents with acute knee joint injury. Method: The clinical and imaging data of 69 adolescents with acute knee joint injuries were analyzed retrospectively. The position of traumatic bone marrow abnormalities, anterior and posterior cruciate ligaments, medial and lateral collateral ligaments, medial and lateral retinacula injuries of knee joint were evaluated by MRI. And the trauma mechanism was collected according to the clinical data. SPSS 13 chi-square test was used for statistical analysis, and P<0.05 was statistically different. Result: 69 patients, including 19 with pivot shift, 17 with lateral patellar dislocation, 12 with hyperextension, 11 with valgus injury and 10 with dashboard injury, were taken as the subjects. Traumatic bone marrow abnormality caused by pivot shift is mainly in the posterior parts of lateral femoral condyle（94.7%）, anterior parts of lateral femoral condyle（84.2%）and posterior parts of lateral tibial plateau（78.9%）, often accompanied by anterior cruciate ligament tears（94.7%）. Abnormality in lateral patellar dislocation is found in patella（100%）, posterior parts of lateral femoral condyle（100%）and anterior parts of the lateral femoral condyle (94.1%), often with medial retinacula injuries（88.2%）. Hyperextension injury includes anterior parts of medial tibial plateau（83.3%）, lateral tibial plateau（75%）and medial femoral condyle（66.7%）, often associated with anterior cruciate ligament（91.7%）and posterior cruciate ligament injuries（58.3%）. Valgus injury mainly links with femur, including posterior parts of lateral femoral condyle（72.7%）, anterior parts of lateral femoral condyle（54.5%）and anterior parts of medial femoral condyle（45.5%）, often accompanied by medial collateral ligament injuries（90.9%）. Dashboard injury mainly involves tibia, including anterior parts of lateral tibial plateau（100%） and medial tibial plateau（90%）, and often with posterior cruciate ligament injuries（70%）. Conclusion: The distribution of traumatic bone marrow abnormality on MRI in adolescents with acute knee joint injuries represents a footprint of specific traumatic mechanism and can be used to predict accurately the presence of specific soft tissue injuries. |
