This pictorial essay reviews the MRI appearance of normal and injured cruciate ligaments. Further investigations are required to identify the intrinsic and extrinsic factors responsible for these discrepancies. Optimal visualization of the anterior cruciate ligament with magnetic resonance imaging requires oblique sagittal imaging planes. A simple template was devised to facilitate this process, resulting in more consistently oriented imaging planes. Objective (average number of images to demonstrate ACL) and subjective (radiologist's confidence level) evaluations of both sequences were performed independently of the other and then comparatively by two radiologists. In 15 of the 22 ACL graft patients the grafts appeared straight when the knee was extended and became convex toward the anterior side when the knee was flexed. Of these, 10 patients had a partial and 12 complete ACL tears. With a threshold value of 45 degrees the ACL angle reached a sensitivity and specificity of 100% for detecting ACL tears. The entire ACL and the meniscus were imaged by oblique sagittal and midsagittal PD-FS, respectively, with the following parameters: TR/TE = 3000/33 ms, field of view (FOV) = 150 × 150 mm, slice thickness = 4 mm, matrix = 320 × 240, pixel size = 0.6 × 0.5 × 4.0 mm, number of excitations = 1, flip angle = 150 degrees, bandwidth = 240 Hz/pixel, and scan time = 2:32 min, ... MRI has a high diagnostic performance for complete ACL ruptures 4 . MRI’s high spatial resolution, excellent soft tissue contrast and multiplanar capabilities make it ideal for evaluating suspected injuries of the m… We performed a 5-year evaluation of anterior cruciate ligament injuries in collegiate men's and women's soccer and basketball programs using the National College Athletic Association Injury Surveillance System. However, ACL abnormalities and secondary findings, alone or combined, failed to surpass the diagnostic value of the ACL angle for predicting ACL tears. Results showed significantly higher anterior cruciate ligament injury rates in both female sports compared with the male sports. ACL cross‐sectional area‐to‐length ratio increased by age only in males (R² = 0.06; P = 0.003). The elevated percentages of T2 and T2⁎ value in superficial LT were most significant (20.738%, 17.525%). In both males and females, ACLs became longer, thicker, and more vertical in sagittal and coronal planes by increasing age (R² > 0.2, P < 0.001 for all associations). Methods: Il est oblique du haut vers le bas, de dedans en dehors. We evaluated the diagnostic utility of magnetic resonance imaging (MRI) for predicting anterior cruciate ligament (ACL) tears using both quantitative parameters and nonquantitative imaging findings. MRI examinations were retrospectively evaluated in a group of patients with arthroscopically confirmed complete ACL tear and in a control group with arthroscopically confirmed intact ACL. One oblique was prescribed from a coronal localizing sequence, while the other was prescribed off an axial series. Secondly, either volume sequence (DESS or FLASH) could be used as the supplementary sequence, to evaluate the ACL, but a limited oblique T1 sequence of the intercondylar notch cannot be recommended. Only 2 patients (0.6%) were recalled (one with a normal, and one with a full thickness ACL tear). Improvements in the quality of MRI images (1.5 and 3 Tesla, multichannel knee coils) with thin slice acquisitions in the plane of the ACL (coronal oblique or sagittal oblique, or water sensitive 3D sequences), ... Each participant was required to rest for 30 min prior to the knee scan to ensure that the cartilage is at resting condition. With an increasing number of people participating in recreational and competitive sporting activities, sports-related injuries of the knee and knee ligaments have increased in incidence. Twenty-three patients and 23 healthy controls were enrolled and underwent quantitative MRI examination. Some reports have noted a higher susceptibility to knee injury, specifically injuries to the anterior cruciate ligament, in female athletes as compared with their male counterparts. The results of this study show that the volume of the contralateral ACL is a valid surrogate measure for a missing ACL on the injured side. Particular emphasis is put on the evaluation of three different quantitative parameters, including a simplified method for measuring the ACL angle. The MR examinations included routine sequences and oblique coronal T2-weighted images, which oriented in parallel to the course of the femoral intercondylar roof. A normal ACL was found in 16.6% (5/30) of patients. The ACL angle may be confidently measured in a single MRI section and can be considered to be the most reliable quantitative parameter for detecting ACL tears. With the right ankle in the normal anatomic position stabilized in a splint, coronal T2-weighted spin-echo sequences (TSE) were obtained. These ligaments are commonly injured in sports and motor vehicle accidents. Finally, a threshold value of 115 degrees gave the posterior cruciate ligament angle a sensitivity of 70% and a specificity of 82%. Radiol 2OOO; Cmciate and posterolateral corner injuries ln tl'e athlete: clinical and magnetic resonance irnaging features. T2 and T2⁎ values were measured in full-thickness as well as superficial and deep layers of each cartilage compartment. The three-dimensional orientation was determined by placing paths through the ligaments and by measuring the angles between corresponding tangents and the three main imaging planes. In particular, it is essential for assessing the cruciate ligaments and any associated meniscal tears. Magnetic resonance imaging (MRI) can diagnose cruciate ligament injuries with high accuracy. Conclusion There were no sex differences in ACL elevation angles (P >0.2) except for larger coronal elevation in 7‐10 years old females compared to age‐matched males (P = 0.012). Ce ligament agit essentiellement entre 70 et 90° de flexion du genou. There was no statistically significant difference in the notch width index between the sexes. Son rôle est de maintenir le tibia sous le fémur : - il contrôle le "TIROIR POSTERIEUR" Ses attaches sont derrière le tibia et sur le condyle interne du fémur. A controlled, prospective study of 30 patients with suspected acute internal derangement of the knee was undertaken to evaluate the sensitivity, specificity, predictive value, and accuracy of nonorthogonal (oblique) sagittal magnetic resonance imaging (MRI) in the assessment of anterior cruciate ligament (ACL) injuries. Background: This non-invasive, in vivo technique for measuring ACL volume may prove useful in future large-scale comprehensive studies of potential risk factors for ACL rupture, in quantifying potential loading effects on ACL size as a prophylactic measure against ACL rupture, and in the use of ACL volume as a screening tool for assessing risk of injury. Additional use of oblique coronal MR imaging of the knee improves diagnostic accuracy in the grading of ACL injury. All rights reserved. In the evaluation of partial ACL injury, four partial tears were correctly diagnosed on nonorthogonal MRI, with one false-positive diagnosis. This article is protected by copyright. Beyond the basic principles of imaging knee injuries great impact was made on the understanding of indirect or collateral findings, even in rare diseases. Only two patients (0.9%) were recalled for additional sequences by the radiologist, and one ACL was normal and one had a full thickness tear at arthroscopy. Examination of anterior cruciate ligament (ACL) anatomy is of great interest both in studying injury mechanisms and surgical reconstruction. We performed a prospective study based on the hypothesis that physiologic differences exist between men and women in strength after adjustments for body weight; that the size of the anterior cruciate ligament is proportionate to the strength of its antagonists, the quadriceps muscles; and that women have a relatively small anterior cruciate ligament, thus predisposing them to a disproportionate number of anterior cruciate ligament injuries. The MRI sequences were evaluated in a blinded fashion by three radiologists, and compared to the knee arthroscopy findings, with the normal ACL acting as internal controls. When faced with a clinical suspicion of knee ligament injury, MRI nowadays has a central role in the diagnostic strategy. The angles deviating from the axial imaging plane were 18.0 degrees for the anterior talofibular ligament, 52.3 degrees for the calcaneofibular ligament and 28.2 degrees for the posterior talofibular ligament. Auteur : Docteur Philippe LORIAUT - Chirurgien Orthopédiste Paris Lilas This includes considerations about how to achieve a high-standard MR imaging study of the knee, and principles of imaging anterior cruciate ligament and meniscal tears. Observed changes in ACL cross‐sectional area‐to‐length ratio indicate that age‐ and sex‐dependent changes in ACL size are not homogenous. Orthogonal imaging failed to correctly identify any of the partial ACL injuries. En cas de lésion … The radiography technicians performed additional ACL sequences in 63 patients (27%); of these, 10 patients had a partial and 12 patients had a complete ACL tear. We believe that we have demonstrated the superiority of T2-weighted nonorthogonal sagittal over conventional orthogonal sagittal ACL MRI in the evaluation of ACL injury. Two independent readers evaluated the status of the ACL by routine knee MR imaging and then by additional oblique coronal imaging. Volume sequences had specificities and accuracies over 95%, with good intraobserver reliability (Kappa 0.859, 95% CI 0.705-1.0). The C-shaped fibrocartilaginous menisci aid in joint stabilization and load transmission. The ACL evaluation for complete tears and a normal ACL on the volume sequences had a sensitivity of 100%, specificity of 97% and accuracy of 97%, excluding partial tears. It is important to establish the distinction between a partial and total tear since it modifies the therapeutic management: a partial tear can heal with functional treatment, which is not the case for complete tears [1,41]. Sa conformation anatomique lui offre une capacité de ciatrisation en cas de lésion. A control population of 30 chondromalacia patients underwent similar evaluation. Quantitative parameters are thus good predictors of ACL tears and may increase the overall sensitivity and specificity of MRI. Angles between these tangents and reference lines RFL-1 (the line connecting the posterior edges of the femoral condyles), RFL-2 (the line through the intercondylar joint space), and RFL-3 (the line connecting the anterior and posterior edge of the medial tibial condyle) were measured. The anterior cruciate ligament, when adjustments have been made for body weight, is smaller in female athletes, and therefore, probably does not compensate for the lack of stiffness and strength. The radiographers did perform additional ACL sequences in 63 patients (27%). The filmed ACL evaluation for complete tears and a normal ACL had a sensitivity of 100%, specificity of 97.1% and accuracy of 97.3%, slightly higher than evaluating on the monitor. Eighteen normal controls and 22 ACL graft patients were studied. Discontinuity was found to be the most useful of the ACL abnormalities. A focus is put on distinct diseases including intra-articular and intraosseous ganglion cysts, iliotibial band friction syndrome, transient osteoporosis, osteonecrosis, osteochondritis dissecans, and imaging of the articular cartilage. The purpose of this study was to determine whether oblique sagittal T2-weighted images of the anterior cruciate ligament (ACL) are better prescribed off axial or coronal localizing images. Eur It is concluded that the morphological changes seen on MR images of ACL grafts from when the knee is extended to when the knee is flexed are different from those in the normal ACL. Twenty healthy volunteers without previous injury to the ankle were included in the study. Axial proton density-weighted (PDw) images of the knees of 20 volunteers were obtained. The early degeneration could occur in various knee cartilage compartments after acute ACL rupture, especially in the superficial layer of LT. T2⁎-mapping might be more sensitive in detecting deep layer of cartilage than T2-mapping. An accurate diagnosis of cruciate ligament injuries is vital in patient care. The usual MRI sequences for the knee are sagittal T1 [6], and proton density-weighting with fat saturation (PD fat-sat) in the three axial, coronal and sagittal planes. To read the full-text of this research, you can request a copy directly from the authors. Patients requiring extra sequences, missed by the radiography technicians, were recalled. The study data support our hypothesis that sex differences in anterior cruciate ligament tear rates are caused primarily by several interrelated intrinsic factors. To ascertain whether radiographers could identify patients requiring supplementary MRI sequences of anterior cruciate ligament (ACL) tears, without a supervising radiologist.Methods Elles sont rares et souvent traumatiques pour ne pas dire qu'elles font suite à un accident de la circulation comme le tibia du motard qui bute contre un pare choc...anecdotiquement une chute sur les genoux pliés qui va faire fortement reculer le tibia sous le femur. Many strategies have been used to improve the visualisation of the ACL including sagittal, coronal oblique sequences, and 3D volume imaging. The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are important stabilizers of the knee. The ACL is best depicted using a sagittal oblique imaging plane angled at 80 degrees from a line through the intercondylar joint space. L’objectif de cette mise au point est de présenter les différents signes IRM directs et indirects de rupture du ligament croisé antérieur (LCA), puis de définir les lésions associées. There were no posterior cruciate, medial, or lateral collateral ligament tears at arthroscopy, used as the gold standard. The extent and severity of such injuries may have important implications with regard to potential return to athletic pursuits as well as impacting upon activities of daily life. ACL volumes were calculated for the left and right sides of 28 individuals using a previously validated MRI-based method. anatomical dimensions, but it remains unknown whether side-to-side differences preclude using the contralateral as a valid surrogate for the ruptured ACL. In 13 intact ligaments, the average number of images clearly demonstrating the entire length of the ACL was 1.77 on the coronally prescribed sequence and 1.31 on the axially prescribed images. Se connecter avec Facebook Ligament croisé postérieur - Ligamentum cruciatum posterius Structures anatomiques Noncontact mechanisms were the primary cause of anterior cruciate ligament injury in both female sports. Magnetic resonance imaging (MRI) has proven to be an excellent tool in the evaluation of meniscal tears and associated pathology. Results: The MRI sequences were independently evaluated in a blinded fashion by two consultant radiologists and a specialist radiology registrar and compared to the subsequent knee arthroscopy, as the gold standard, to determine the diagnostic performance statistics.ResultsThe cohort was on the knee arthroscopy weighting list and comprised 205 patients with chronic, 20 acute and 6 acute on chronic mechanical knee symptoms. Two patients in the control population demonstrated evidence of chronic ACL tears. In the acute hemarthrosis patient population, the incidence at arthroscopy of acute complete ACL tears was 60% (18/30); of partial ACL tears, 13.3% (4/30); and of chronic tears, 10% (3/30). We hypothesized that ACL size and orientation will change by age during skeletal growth and maturation with different trends in males versus females. Les aspects anatomiques et cliniques sont également exposés afin de mieux comprendre l’apport de l’IRM dans la conduite diagnostique et dans la prise en charge thérapeutique de la rupture du LCA. Methods The study had ethical approval and two hundred and thirty one consecutive prospective MRI patients with mechanical knee symptoms (77 females, 154 males, of mean age 43.5, range 18–82 years) gave written informed consent. One hundred matched high school basketball players, 50 male and 50 female, were evaluated with anthropometric measurements, body fat analysis, muscle strength evaluation, and magnetic resonance imaging measurements of the intercondylar notch and cross-sectional area of the anterior cruciate ligament at the outlet. The severity of the ACL injury was graded using a 4-point system from MR images, namely, intact, low-grade partial tear, high-grade partial tear, and complete tear, and results were compared with arthroscopic findings. Orienting the imaging planes according to the calculated angular deviation allows the full-length visualization of the ligaments and is the basis for optimal imaging of the lateral ankle ligaments. Side-to-side ACL volume was also well correlated (correlation=0.91, p<0.0001). Spin-echo (SE) T1-weighted images (TR 330 ms/TE 15 ms, NEX 1) were obtained with a slice thickness of 3 mm. Two hundred and thirty-one consecutive patients (77 females; 154 males; average age 43.5, range 18 to 82 years; 205 with chronic, 20 acute, and 6 acute on chronic symptoms) underwent knee arthroscopy for mechanical symptoms within a week of MRI. ... Les séquences habituelles pour les IRM de genou sont : le T1 sagittal [3], la densité protonique avec saturation de la graisse (DP FS) dans les trois plans axial, coronal et sagittal [28]. The male players were taller and heavier than their female counterparts, although they had 11% less body fat. Many imagers can perform oblique sagittal imaging, but the operator must set the proper degree of obliquity for the examination. Le LIGAMENT CROISE POSTERIEUR (LCP) est un des ligaments croisés du genou. An additional volume sequence was beneficial when filmed. Le ligament croisé postérieur est rattaché à la fosse intercondylaire postérieure du tibia et à l'extrémité postérieure du ménisque latéral. Patients requiring extra sequences, missed by the radiographers, were recalled. Oblique sagittal images parallel to the ACL were obtained at various flexed angles of the knee joint. Accurate interpretation of the MRI examination requires a meticulous MRI technique, knowledge of the imaging anatomy, and understanding of the lesion appearance. Weighted kappa statistics were used to analyze the diagnostic accuracy of routine knee MR imaging with and without additional oblique coronal imaging. With a threshold value of 0 degrees the Blumensaat angle had a sensitivity of 90% and a specificity of 98%. This article discusses the MR imaging and clinical features of sports-related injuries of the cruciate ligaments and posterolateral corner of the knee, highlighting the implications of such injuries on joint function.

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