The meniscus may also become hypertrophic. Biologic augmentation with application of exogenous fibrin clot or growth factors may be combined with the repair to promote healing. Radiographs may Congenital absence of the meniscus is extremely rare and has been documented in TAR syndrome and in isolated case reports.2,3 Singh K, Helms CA, Jacobs MT, Higgins LD. The lateral meniscus is more circular, and its anterior and posterior horns are nearly equivalent in size in cross section. The shape of the meniscus is formed at the eighth week of Acute partial interstitial to near complete anterior cruciate ligament tear is noted at its posterior end with femoral deep lateral sulcus sign. Discoid lateral meniscus (DLM) is a common anatomic variant in the knee typically presented in young populations, with a greater incidence in the Asian population than in other populations. Tears in the red zone have the potential to heal and are more amenable to repair. (PDF) Sensitivity and Specificity of MRI in Diagnosing Concomitant Anterior Horn Meniscal Tears — Fact or Fiction - Relias Media Semin Musculoskelet Radiol 2005;9(2):11624, Chung KS, Ha JK, Ra HJ, Nam GW, Kim JG. The remaining 42 cases were located in the red zone (19 cases) or the red-white zone. (as previously described), meniscal cyst,26 discoid lateral meniscus in the same knee (Figure 9),25 and pathologic medial patella plica.27. Lateral meniscal variant with absence of the posterior coronary ligament. 6 months post-operative she had increased pain prompting follow-up MRI. The posterior root of the lateral meniscus (PRLM) attaches along the posterior aspect of the intercondylar eminence of the tibia (Fig. ISAKOS: 2023 Congress in Boston, USA : Abstract Analysis of Risk The examiner can test the entire posterior horn up to the middle segment of the meniscus using the IR of the tibia followed by an extension. The MRI showed complete ACL tear with displaced bucket handle medial meniscus tear. occur with minor trauma. Results: In a consecutive series of 301 ACL reconstructions, 50 patients (33 male, 17 female) with a mean age of 29.6 years (range, 14-61 years) were diagnosed with a medial meniscal ramp lesion at . Ideal for residents, practicing radiologists, and fellows alike, this updated reference offers easy-to-understand guidance on how to approach musculoskeletal MRI and recognize abnormalities. appearance.12 It is now believed that the knee develops from a treatment for stable complete or incomplete types of discoid lateral of the distal femur and proximal tibia, and in the case report of AJR Am J Roentgenol. typically into the anterior cruciate ligament. for the ratio of the sum of the width of the anterior and posterior variant, and discoid medial meniscus. Samoto N, Kozuma M, Tokuhisa T, Kobayashi K. Diagnosis of discoid lateral meniscus of the knee on MR imaging. 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). Connolly B, Babyn PS, Wright JG, Thorner PS. Symptomatic anomalous insertion of the medial meniscus. A meta-analysis of 44 trials. As visualized on sagittal MR images, the anterior horn of the medial meniscus is shorter than the posterior horn, whereas the anterior and posterior horns of the lateral meniscus are of equal length. The lateral meniscus is produced by the varus tension and tibial IR. Type 1: A complete slab of meniscal tissue with complete tibial coverage. These features constitute O'Donoghue unhappy triad. History of a longitudinal medial meniscus tear managed by repair and concurrent ACL reconstruction. Imaging characteristics of the Knee Surg Sports Traumatol Arthrosc. Direct MR arthrography requires intraarticular injection of 20-50 mL of dilute gadolinium contrast prior to imaging which distends the joint capsule and offers a high signal to noise ratio on T1-weighted images with contrast extension into the meniscal substance indicating a recurrent tear or an unhealed repair. congenital absence of the cruciate ligaments. The lateral meniscus is one of two fibrocartilaginous menisci of the knee. A tear of the ACL should also, in practice, not be a posterior horn of the medial meniscus include a triangular hypointense 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. He presented after a few months with symptoms of instability. The medial meniscus is more tightly anchored than the lateral meniscus, allowing for approximately 5mm of anterior-posterior translation. St. Louis County's newspaper of politics and culture Lateral meniscus extrusion was present in six (23%) of 26 LMRTs and five (2.2%) of 231 patients with normal meniscus roots ( P < .001). Mucinous degeneration of meniscus can also produce abnormal signal within a meniscus which does not contact an articular surface and should not be mistaken for a tear. Radial or oblique tear congurations close to or within the meniscus . Examination of the knee showed a mild effusion, 1+ Lachman, positive Pivot shift, and mild tenderness to both medial and lateral joint lines. Meniscus Tear MRI Correlation | SpringerLink Of the 14 athletes, 8 repairs were performed, 5 patients . This has also been described as grade 2 signal [, Sagittal fat-suppressed T2 image of a 14-year-old patient showing a grade 2 signal in the posterior horn of the medial meniscus (PHMM). Note the symmetrical shape of the lateral meniscus (left) with similar size of the anterior and posterior horns. 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. in 19916. For DSR inquiries or complaints, please reach out to Wes Vaux, Data Privacy Officer, The common insertion of the anterior cruciate ligament (ACL) and the AHLM root may provide a pathway for disease. Create a new print or digital subscription to Applied Radiology. We hope you found our articles published a case series of anterior horn tears of the lateral meniscus in 14 soccer players (mean age 20.2 years). was saddle shaped. Unable to process the form. They found that 76 (8%) of these indicated a tear of the anterior horn of either the medial or lateral meniscus. Discoid lateral meniscus was originally believed to result from an Suprapatellar plica noticed, with no related cartilaginous erosions. The posterior cruciate ligament is intact. MRI features are consistent with torn lateral meniscus with flipped anterior horn superomedial and posterior, resting superior to the posterior horn. History of medial meniscus posterior horn partial meniscectomy. Footballer's Lateral Meniscus: Anterior Horn Tears of the Lateral Heron, D, Bonnard C, Moraine C,Toutain A. Agenesis of cruciate 2020;49(1):42-49. An alternative way of fastening the allograft to the donor knee involves harvesting the meniscus with a small bone plug attached to each root and then securing the plugs within osseous tunnels drilled in the recipient tibia. The anterior meniscofemoral ligament (Humphrey ligament) attaches proximally on the medial femoral condyle, inferior to the PCL insertion. A tear was found and the repair was revised at second look arthroscopy. Anterior lateral cysts extended . The medial compartment articular cartilage is preserved, and the meniscal body is not significantly extruded (16D). 2. Is sport activity possible after arthroscopic meniscal allograft transplantation? It is often explained by fibers of the anterior cruciate ligament and the covering synovium . Radiology. During an arthroscopy, we have the choice of either repairing the meniscus tear or removing the torn piece. The anterior horn inserts on the tibia and continues laterally to the anterior horn of the lateral meniscus via the transverse intermeniscal ligament. Shepard and colleagues at UCLA specifically analyzed this by reviewing 947 consecutive MRIs. Lee, J.W. 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. The patient subsequently underwent successful partial medial meniscectomy. Nakajima T, Nabeshima Y, Fujii H, et al. normal knee. Concise, to-the-point text covers MRI for the entire musculoskeletal system, presented in a highly templated format. Anterior horn of the lateral meniscus: another potential - PubMed When bilateral, they are usually symmetric. On the sagittal proton density-weighted image (11A), signal contacts the tibial surface. 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. That reported case was also associated with 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. This emphasizes the importance of meniscal repair over meniscectomy when possible and the need for meniscal preservation when a partial meniscectomy is necessary. The example above demonstrates the importance of baseline MRI comparison when evaluating the postoperative meniscus. Kocher MS, Klingele K, Rassman SO. Comparison of Medial and Lateral Meniscus Root Tears - PLOS Another finding is the abnormal size or shape of the meniscus, which would indicate damaged surfaces [, To provide a greater degree of accuracy, De Smet advocated the two-slice-touch rule. To call a definite tear, one should see increased signal contacting the articular surface of the menisci on at least two images (sagittal or coronal). They often tend to be radial tears extending into the meniscal root. In some patients, hyperintense signal may persist at the repair site on conventional MRI for several years and is thought to represent granulation tissue. Meniscal transplant is usually reserved for patients younger than 50 years who have normal axial alignment. Among these 26 studies of an LMRT . medial meniscus are extremely uncommon and should not be a diagnostic In contrast to the medial meniscus, the posterior horn of the lateral meniscus is additionally secured by the meniscofemoral ligaments (MFL). 1 ). 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. Symptoms of anterior horn tears were very similar to those of meniscal tears of the midbody or posterior horn, including catching, pain with knee flexion, and swelling. posterior horn usually measures 12 mm to 16 mm in the sagittal plane in The Journal of bone and joint surgery American volume. Type 1 is most common, and type The most widely used diagnostic modalities to assess the ligament injuries are arthroscopy and Magnetic Resonance Imaging (MRI). Association of Parameniscal Cysts With Underlying Meniscal Tears as When the cruciate Dr. Michael Gabor answered Diagnostic Radiology 35 years experience No,: It doesn't sound like a bucket handle tear Anterior horn tear of the lateral meniscus in footballers with a stable knee is characterized by pain at the anterolateral aspect of the knee during knee extension, especially when kicking. On MRI, longitudinal tears appear as a vertical line of abnormal signal contacting articular surface. Sagittal proton density-weighted image (5A) through the medial meniscus at age 12 shows the initial horizontal tear in the posterior horn (arrow) subsequently treated with partial meniscectomy. Get unlimited access to our full publication and article library. Flipped meniscus - anterior horn lateral meniscus | Radiology Case These tears are usually degenerative in nature and usually not associated with a discrete injury [. morphology but lacks its posterior attachments; ie, the meniscotibial The speckled appearance of the anterior horn of lateral meniscus is a feature that can be seen as a normal variant on MRI knee scans. the medial meniscus. On the fat-supressed proton density-weighted coronal (17A) and axial (17B) images, notice the trapazoidal shaped bone bridge (arrow) placed in the tibial slot with menscal allograft attached at the anterior and posterior roots. Fat supressed coronal proton density-weighted (19C, D) and sagittal proton density-weighted (19E) images demonstrate postoperative changes from interval posterior horn partial meniscectomy with a thin rim of posterior horn remaining (arrow) and subchondral fractures in the medial femoral condyle and medial tibial plateau (arrowheads) with marked progression of full-thickness chondral loss in the medial compartment and extruded meniscal tissue. 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. Check for errors and try again. Most horizontal tears extend to the inferior articular surface. Objectives: Low-field MRI at 0.55 Tesla (T) with deep learning image reconstruction has recently become commercially available. In this section, the major patterns of tears are described and depicted in MRIs and arthroscopy images. Note that signal does not contact articular surface, The most common criterion for diagnosing meniscus tear on MRI is an increased signal extending in a line or band to the articular surface. Conventional MRI is the least invasive modality for evaluation of a meniscal repair but has lower sensitivity, specificity and accuracy than direct or indirect arthrographic MRI. The self-reported complication rate for partial meniscectomy is 2.8% and meniscus repair is 7.6%. On imaging alone, the radiologist may not be able to distinguish a residual tear (failed repair) from a recurrent tear in the same location. Sagittal proton density-weighted image (5B) through the medial meniscus at age 17 reveals an incomplete tibial surface longitudinal tear (arrow) in a new location and orientation. MR arthrogram fat-suppressed sagittal T1-weighted image (11C) shows no gadolinium in the repair. Clin Orthop Relat Res 2013; 471: pp. 2059-2066, Kinsella S.D., and Carey J.L. meniscal diameter. Following meniscal allograft transplantation (Figure 17), complications occur in up to 21% of procedures, including allograft failure and progressive cartilage loss.19 Repeat operations occur in up to 35% of patients, 12% requiring conversion to total knee arthroplasty. MRI has high sensitivity and specificity for detecting meniscus tears in patients without prior knee surgery. patella or Hoffas fat pad, and should be fairly easily differentiated After failing conservative management with NSAIDs, PT, and activity modification, he underwent an MRI. If a meniscus tear shows up on a MRI, it is considered a Grade 3. Conventional MRI imaging of the postop meniscus offers a noninvasive evaluation of the knee, but postoperative changes can mimic a recurrent or residual meniscus tear. : Complications in brief: arthroscopic partial meniscectomy. of the AIMM into the ACL is classified as Type 1 (inferior third), Type 2 Kim SJ, Moon SH, Shin SJ. 2006; 187:W565568. Dickhaut SC, DeLee JC. What is anterior horn of meniscus? - KnowledgeBurrow.com Incidence and Detection of Meniscal Ramp Lesions on Magnetic Resonance The anterior and posterior meniscofemoral ligaments (Humphrey and Wrisberg respectively) are commonly present with one or both found in 93-100% of patients.9 The lateral meniscus is more loosely attached than the medial and can translate approximately 11mm with normal knee motion.10. The same imaging criteria (as for the case of greater than 25% partial meniscectomy), the presence of fluid signal on T2-weighted or contrast extending into the meniscal substance is used to diagnose a recurrent tear. 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 Again, this emphasizes the importance of accurate history, prior imaging and operative reports. posterior fascicles and meniscotibial ligament are absent and a high Intensity of signal contacting meniscal surface in recurrent tears on MR arthrography compared with that of contrast material. Analytical, Diagnostic and Therapeutic Techniques and Equipment 13. diagnostic dilemma, as the AIMM band will be seen to extend to the Posterior Horn Medial Meniscus Tears - Howard J. Luks, MD
anterior horn lateral meniscus tear: mri