MRI Reconstruction Observations And Clinical Application Of The Menisci Of Knee Joint

BackgroundMeniscus injury is the most common clinical disease, seriously affecting the motion of the knee joint, early diagnosis and prognostic judgment of choice has important significance for clinical treatment. Density resolution and spatial resolution of MRI is higher and can be multi-dimensional, arbitrary slice imaging, clearly show the fine meniscus and its surrounding structures, the accuracy, sensitivity and specificity have higher meniscus injury, is by far the best imaging examination of meniscus.ObjectiveUsing MRI image post-processing multiplanar reconstruction(MPR), to observe the medial meniscus(MM) and lateral meniscus(LM) anatomical features of structure and signal, measure the medial and lateral meniscus, anterior horn, lateral horn, before the body, after the posterolateral corner angle, width and thickness, ratio and the tibial longitudinal, transverse diameter, and the changes of different age stages, the lateral meniscus in each part of the structure of the width and thickness, position and range of meniscus tear, provides the reference for the diagnosis of meniscal lesions, the treatment of operation and postoperative evaluation.Materials and methodsCollection of image section steel plant MRI general hospital in Anyang city during the period from 2012 January to 2013 December,100 patients underwent knee joint, MRI scanning of adults and no significant lesions, including 50 cases of male, female 50 cases, age 23-55 years old.60 the 70 side of the knee meniscus injury patients, including 30 cases of male,19 are left side, the 16 side of the right knee,30 cases of female,20 are left side, right knee 15 side, aged 20-56 years old. The knee joint meniscus MRI image data is transmitted to the 3D-reconstruction workstation, using multiplanar reconstruction(MPR), observations of meniscus of knee joint in MRI image reconstruction on a workstation, and arthroscopic examination results were analyzed.Results1. MRI imaging of normal meniscus showed low signal uniform, the edge of hypertrophy, closer to the center of the thinner; connected with the joint capsule, the articular cartilage, and the lower edge of the stick. In the lateral meniscus, length and the distance between the anterior, posterior horn were 41.70±3.44 mm,34.40±2.91 mm and 38.51±9.88 mm,30.53±5.87 mm, the medial meniscus(MM) of various structure width from front to back, gradually widened, lateral meniscus(LM) rake angle, width body, posterior horn of the medial meniscus(MM) uniform, the front angle, body, when the thickness of the uniform angle, lateral meniscus(LM) front angle is body, posterior horn was thinned, the thickness difference of body and posterior horn is not obvious.2. The ratio of medial and lateral meniscal body width and tibial transverse diameter were 0.084±0.023 and 0.097±0.023, ratio before and after the angle width and the corresponding tibial longitudinal diameter of 0.138±0.022,0.239±0.045 and 0.223±0.042,0.215±0.035, ratio of the distance and the tibial longitudinal before and after the angle between the diameter of 0.936±0.250 and 0.981±0.191, the ratio of the values were relatively constant.3. The medial meniscus(MM) in the anterior horn width, body width, anterolateral, posterolateral corner angle width width, in less than 30 years old group and the 30-50 years old group, and there was significant difference between the more than 50 years old group, the medial meniscus(MM) body thickness, the thickness of the posterolateral corner, between less than 30 age group with more than 50 years old group and there was significant difference, medial meniscus(MM) body width, there are significant differences between 30-50 years old group with more than 50 years old group. The lateral meniscus(LM) body width, body thickness, width between the posterolateral corner, in less than 30 years old group and 30-50 years old, more than 50 years old group and there was significant difference.4. MRI reconstruction imaging diagnosis of meniscal tear the accuracy, sensitivity and specificity were 92.25%,89.74% and 95.05%. Medial meniscus tears in 53.7%, torn lateral meniscus tear of the medial meniscus of 46.3%, slightly higher than the lateral meniscus tear of meniscus tear, to have level longitudinal tear tear, and compound tear, accounted for 26.8%,29.3% and 22% of the total number of meniscus tear. Meniscus tear parts often occur in the meniscus posterior horn of the medial meniscus(MM), and more than the lateral meniscus(LM), the medial meniscus(MM) and there was significant difference between the tear frequency front angle, body, angle. The concomitant injury, with the highest incidence of meniscus tear of the anterior cruciate ligament tear.Conclusion1.In vivo MRI reconstruction image observation of the meniscus, have helped identify the meniscus lesions and variation, as a reference for the diagnosis of meniscal lesions, operation.2. Each department within the lateral meniscus width and the distance between the anterior, posterior horn and the tibial longitudinal, transverse diameter of the relatively constant, provides a reference method for clinical on tibial plateau bony standard design of reasonable size of meniscus.3. Each department within the structure, the lateral meniscus with the growth of age and broadening, thickening,30 years old is the dividing point of the meniscus size, has clinical significance to slow down the degeneration and osteoarthritis of knee meniscus circumferentia displacement arrival.4. MRI image reconstruction can accurately display the location and extent of the meniscus tear, has guiding significance for typing of meniscus tear and surgical planning etc.