anterior horn lateral meniscus tear: mri anterior horn lateral meniscus tear: mri

MR imaging and MR arthrography for diagnosis of recurrent tears in the postoperative meniscus. For DSR inquiries or complaints, please reach out to Wes Vaux, Data Privacy Officer, The example above demonstrates the importance of baseline MRI comparison when evaluating the postoperative meniscus. 2. RESULTS. Of the 54 participants, 5 had PHLM tears and 49 were normal. Pain is typically medial and activity-related (e.g. The meniscal body is firmly attached to the deep portion of the medial collateral ligament complex via the meniscotibial ligament. anterior horn of the medial meniscus into the anterior cruciate ligament The incidence of lateral meniscus posterior root tears was approximately 4 times higher than of medial meniscus posterior root tears in both primary (12.2% vs 3.2%) and revision (20.5% vs 5.6%) ACLRs. This case features the following signs of meniscal tear: Case courtesy, Prof. Dr. Khaled Matrawy, Professor of radiology, Alexandria university, Egypt. Advantages include a less invasive method of introducing intraarticular contrast, the ability to identify areas of hyperemic synovitis or periarticular inflammation based on enhancement and administration can be performed by the technologist. Diagnosis of meniscal tears on MRI improves when these guidelines are followed to optimize signal-to-noise ratio: high-field-strength magnets are preferable (1.5 T and stronger); a high-resolution surface coil should be used; the field of view should only encompass the necessary structures and routinely be 16 cm or less; image slices should not be too thick (34 mm); and the matrix size should be at least 256192 or higher [, A normal meniscus is low signal on all sequences. Become a Gold Supporter and see no third-party ads. Longitudinal medial meniscus tear managed by repair (arrow). Because there is less pressure on the meniscus there, it is difficult to evaluate the anterior region of the meniscus. They found that 76 (8%) of these indicated a tear of the anterior horn of either the medial or lateral meniscus. . Longitudinal (longitudinal, peripheral-vertical) tears run parallel to the circumference of the meniscus along its longitudinal axis, separating the meniscus into central and peripheral portions (Fig. The medial meniscus is more tightly anchored than the lateral meniscus, allowing for approximately 5mm of anterior-posterior translation. 3. the example shown (Figures 1 and 2), the entire medial meniscus is There is no universally accepted system for classifying meniscal tear patterns. Clinical imaging. Meniscal root tearsare a type of meniscal tearin the knee where the tear extends to either the anterior or posterior meniscal root attachment to the central tibial plateau. On medial posterior root tears there is often 2: On posterior root radial tears of the lateral meniscus, the appearance may be similar to radial tears in other locations. has shown that 41% of patients with a surgically confirmed torn post-operative meniscus had signal intensity within the meniscus extending into the articular surface which was lower than the signal intensity of gadolinium contrast.14 Like the presence of a line of intermediate T2 signal extending into the articular surface on conventional MRI, diagnosis of a torn post-operative meniscus on MRI arthrography is challenging when the intra-meniscal signal intensity is not as bright as gadolinium contrast. To provide the highest quality clinical and technology services to customers and patients, in the spirit of continuous improvement and innovation. signal fluid cleft interposed between the posterior horn and the capsule Twenty-one had ACL tears; all those with an PHLM tear had an ACL tear. Vertical flap (oblique, flap, parrots beak) tears are unstable tears and occur in younger patients. attachment of the posterior horn is the Wrisberg meniscofemoral The purpose of our study was to determine if cysts of the ACL are the origin of cysts adjacent to the AHLM. The posterior root of the medial meniscus attaches to the tibia, just anterior and medial to the posterior cruciate ligament (PCL). Radiology. [emailprotected]. The trusted source for healthcare information and CONTINUING EDUCATION. Complex or deep radial tears were found in three of five cases of lateral meniscus extrusion and normal root. 2006;239(3):805-10. In this case, we can determine that there is a new tear in a different location. medial meniscus are extremely uncommon and should not be a diagnostic The lateral meniscus is produced by the varus tension and tibial IR. Radial tears comprise approximately 15 % of tears in some surgical series [. MR imaging evaluation of the postoperative knee. There was no evidence of meniscal extrusion or a meniscal ghost sign (Fig. menisci (Figure 8). 2019: Factors associated with bilateral discoid lateral meniscus tear in patients with symptomatic discoid lateral meniscus tear using MRi and X-ray Orthopaedics and Traumatology Surgery and Research: Otsr 105(7): 1389-1394 Of those 31 patients who underwent arthroscopic examination, there were only 8 true anterior horn tears (26% true positive rate) and 18 had normal or intact menisci in all zones. Sagittal proton density-weighted image (10A) demonstrates increased signal extending to the articular surface consistent with granulation tissue. On MRI, longitudinal tears appear as a vertical line of abnormal signal contacting articular surface. Magnetic resonance imaging (MRI) revealed an elongated free edge of the diffusely enlarged lateral meniscus extending toward the intercondylar region on coronal T1-weighted images (Figure 1A). Sagittal T2-weighted image (10B) reveals no fluid at the repair site. Monllau J, Gonzalez G, Puig L, Caceres E. Bilateral hypoplasia of the medial meniscus. Connolly B, Babyn PS, Wright JG, Thorner PS. posterior horn usually measures 12 mm to 16 mm in the sagittal plane in Case study, Radiopaedia.org (Accessed on 04 Mar 2023) https://doi.org/10.53347/rID-75066. diminutive (1 mm) with no increased signal to suggest root attachment The patient underwent partial medial meniscectomy and ACL reconstruction. Am J Sports Med 2010; 38:15421548, LaPrade RF, Matheny LM, Moulton SG, James EW, Dean CS. In this case, having the prior MRI exam is useful for showing the location of the initial tear and the new tear in a different location. Of these 45 patients, there was an average of 3.74 additional pathological conditions noted on the MRI scan, mainly including degenerative arthrosis or patellar chondromalacia to explain the patients continued pain. The patient had a recent new injury with increased pain. Repair devices including arrows, darts and sutures are used to approximate the torn edges of the meniscus. 4. Congenital discoid cartilage. For root tears in general, sagittal imaging may demonstrate a meniscal ghost sign. On the sagittal proton density-weighted image (11A), signal contacts the tibial surface. The menisci are C-shaped fibrocartilaginous structures composed of radial and circumferential collagen fibers that have several roles, including joint stabilization, load distribution, articular cartilage protection and joint lubrication. Criteria for a recurrent tear after greater than 25% meniscectomy Definite surfacing T2 fluid signal (or high T1 signal isointense to intra-articular gadolinium on MR arthrography) on 2 or more images or displaced meniscal fragment.17 Definite surfacing fluid signal on only one image represents a possible tear. Relevant clinical history, prior imaging and use of operative reports will significantly improve accuracy of post-operative interpretations. Indications for a partial meniscectomy include meniscal tears not amenable to repair which includes non-peripheral tears with a horizontal, oblique or complex tear pattern and nontraumatic tears in older patients. acromioclavicular, sternoclavicular, and temporomandibular joints. The MRI showed complete ACL tear with displaced bucket handle medial meniscus tear. No gadolinium extension into the meniscus on fat-suppressed sagittal T1-weighted (9B) post arthrogram view. the intercondylar notch, most commonly to the mid ACL, and less commonly In this case the roots remained intact at the bone bridge, but the meniscal allograft detached from the joint capsule at the posterior and middle third with displacement into the central weightbearing surface (arrowheads) on sagittal T2-weighted (17C) and fat-suppressed axial proton density-weighted (17D) images. The sutures are tied over a cortical fixation device or Endobutton (short arrow) with the knee flexed at 90 to secure the root repair. CT arthrography is recommended for patients with MRI contraindications or when extensive susceptibility artifact from hardware obscures the meniscus. Knee Surg Sports Traumatol Arthrosc. Illustration of the medial and lateral menisci. Choi S, Bae S, Ji S, Chang M. The MRI Findings of Meniscal Root Tear of the Medial Meniscus: Emphasis on Coronal, Sagittal and Axial Images. 2059-2066, Kinsella S.D., and Carey J.L. The intrameniscal ligament where it diverges from the back of the anterior horn of the lateral meniscus is also a common area misinterpreted as a tear. Kelly BT, Green DW. Direct and indirect MR arthrography have been shown to be superior to conventional MRI for detection of recurrent meniscal tears in greater than 25% partial meniscectomies and meniscal repairs; however, conventional MRI is commonly used for initial evaluation of the postoperative meniscus with MR arthrography reserved for equivocal cases. While they can arise from a number of mechanisms, root tears are generally thought to be chronic 5. Radiographic knee dimensions in discoid lateral meniscus: Comparison with normal control. A An intact meniscal repair was confirmed at second look arthroscopy. congenital absence of the cruciate ligaments. (middle third), or Type 3 (superior third; intercondylar notch) (Figure This mesenchymal of the distal femur and proximal tibia, and in the case report of This scan showed a radial MMT. The meniscus is two crescent-shaped, thick pieces of cartilage that sit in the knee between the tibia and the femur. runs from the anterior horn of the medial meniscus to either the ACL or MRI of the knee is commonly indicated for evaluation of unresolved or recurrent knee pain following meniscal surgery. treatment for stable complete or incomplete types of discoid lateral Meniscal root tears are a type of meniscal tear in the knee where the tear extends to either the anterior or posterior meniscal root attachment to the central tibial plateau. Sagittal proton density-weighted image (9A) demonstrates no high signal abnormality. The MRI revealed a longitudinal tear in the posterior horn of the lateral meniscus. pivoting). Discoid lateral meniscus: Prevalence of peripheral rim instability. However, the use of MRI arthrography should be considered for post-operative menisci with equivocal findings on conventional MRI as the presence of high gadolinium-like signal within the meniscus would allow for a definitive diagnosis of re-tear. Variations in meniscofemoral ligaments at anatomical study and MR imaging. 2013;106(1):91-115. is much greater than in a discoid lateral meniscus, and the prevalence Volunteerism and Sports Medicine: Where do We Stand? Menisci are present in the knees and the {"url":"/signup-modal-props.json?lang=us"}, Weerakkody Y, Baba Y, Knipe H, et al. of the menisci can be summarized as providing: Clark and Ogden studied the natural development of the menisci in the show cupping of the medial tibial plateau, proximal medial tibial physis On MR images of the knee it is sometimes impossible to determine with confidence if a focus of high signal in the meniscus is confined to the substance of the meniscus or if it extends to involve the surface. After preparing the recipient knee by creating a matching keyhole trough in the tibia, the surgeon slides the allograft bone plug into its matching tibial slot and sutures the periphery of the allograft meniscus to the capsule. Normal menisci. Kocher MS, Klingele K, Rassman SO. Lateral meniscus tears of the posterior root are a common concomitant injury to anterior cruciate ligament (ACL) tears [6, 16, 20]. Radiology. This case features the following signs of meniscal tear: absent bow tie appearance of the lateral meniscus ghost meniscus: empty location of the anterior horn of the lateral meniscus discoid lateral meniscus, including a propensity for tears to occur and Healed peripheral medial meniscus posterior horn repair and new longitudinal tear in a different location. Congenital absence of the meniscus is extremely rare and has been documented in TAR syndrome and in isolated case reports.2,3 Pullout fixation of posterior medial meniscus root tears: correlation between meniscus extrusion and midterm clinical results. Thirty-one of these patients underwent subsequent arthroscopic evaluation to allow clinical correlation. Pagnani M, Cooper D, Warren R. Extrusion of the Medial Meniscus. patella or Hoffas fat pad, and should be fairly easily differentiated The ideal technique for imaging the postoperative meniscus is a matter of active controversy and depends on the operation performed, surgeon preference and clinical question (concern for recurrent meniscal tear versus articular cartilage). 2014; 43:10571064, McCauley TR. In MRI features are consistent with torn lateral meniscus with flipped anterior horn superomedial and posterior, resting superior to the posterior horn. What is your diagnosis? Discoid meniscus in children: Magnetic resonance imaging characteristics. Still, many clinicians choose to use conventional MRI for initial postoperative imaging which may show displaced meniscal fragments, new tears in different locations or internal derangement not involving the meniscus. Exam showed a mild effusion and medial joint line tenderness. The ends of the anterior and posterior horns are firmly attached to the tibia at their roots. Extrusion is commonly seen following root repair. slab-like configuration on sagittal MR images, with > 3 bowties This is a critical differentiation because the latter represents meniscal tears that can be A recurrent tear was proved at second look arthroscopy. Methods Eighteen patients who had arthroscopically confirmed partial MMPRTs were included. The anterior horn inserts on the tibia and continues laterally to the anterior horn of the lateral meniscus via the transverse intermeniscal ligament. The camera can visualize the meniscus and other structures within the knee. Synopsis: In a consecutive series of nearly 1000 knee MRIs, there was a 74% false-positive rate for the diagnosis of anterior horn meniscal tears. A detached posterior root is functionally equivalent to a total meniscectomy with loss of its ability to withstand hoop stress. structure on sagittal images on T1, proton density, and fat-saturated Normal Among these 26 studies of an LMRT . Create a new print or digital subscription to Applied Radiology. Long-term outcome after arthroscopic meniscal repair versus arthroscopic partial meniscectomy for traumatic meniscal tears. One of the most frequent indications for arthroscopic knee surgery is a meniscal tear.1 It is estimated that 1 million meniscus surgeries are performed in the U.S. annually with 4 billion dollars in associated direct medical expenditures.2 Meniscal surgeries include partial meniscectomy, meniscal repair and meniscal replacement. A meta-analysis of 44 trials. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Am J Sports Med 2017; 45:4249, ElAttar M, Dhollander A, Verdonk R, Almqvist KF, Verdonk P. Twenty six years of meniscal allograft transplantation: is it still experimental? (PubMed: 17114506), BakerJC, FriedmanMV, RubinDA (2018) Imaging the postoperative knee meniscus: an evidence-based review. A Wrisberg type variant has not been documented in Arthrofibrosis and synovitis are also relatively common. Dickhaut SC, DeLee JC. According to these authors, increased signal to the surface on only one slice should be interpreted as a possible tear. Cases of only one abnormal slice correlated to tears at arthroscopy 55 % of the time for the medial meniscus and 30 % for the lateral [, Accuracy of diagnosing meniscus tear with these criteria has been good.