When the cruciate Damaged meniscal tissue is removed with arthroscopic instruments including scissors, baskets and mechanical shavers until a solid tissue rim is reached with the meniscal remnant contoured, preserving of as much meniscal tissue as possible. to the base of the ACL or the intercondylar notch. For information on new subscriptions, product hypoplastic meniscus was not the cause of the patients pain, suggesting We will review the common meniscal variants, which Fat suppressed sagittal T1-weighted MR arthrogram (5C) demonstrates gadolinium within the tear (arrow). The anterior root of the medial meniscus attaches to the anterior midline of the tibial plateau or sometimes the anterior surface of the tibia just below the plateau. This mesenchymal As a result, the accuracy rate of diagnosis by MRI is 83.3%. | Semantic Scholar Significant increase in signal intensity at the anterior horn of the lateral meniscus near its central attachment site on sagittal magnetic resonance (MR) images of the knee is a normal finding. Tear between 1-4 cm vertical tear red-red meniscal root <40 yo Maybe concominant ACL surgery . The self-reported complication rate for partial meniscectomy is 2.8% and meniscus repair is 7.6%. Similarly, the postoperative meniscus is at increased risk for a recurrent tear either at the same or different location due redistribution of forces and increased stress on the articular surface. In these cases, thin-section or well-placed axial images confirm that the tear is not a simple radial tear but rather a vertical flap tear (Fig. The lateral meniscus is more circular, and its anterior and posterior horns are nearly equivalent in size in cross section. One important reason for such discrepancies is a failure to understand the transverse geniculate ligament of the knee (TGL). The posterior root lies anterior to the posterior cruciate ligament. This is a critical differentiation because the latter represents meniscal tears that can be (Figure 1). If a horizontal tear involves a long segment of the meniscus, the central fragment may displace centrally from the peripheral portion of the meniscus [, Bucket handle tears (BHT) often cause pain and mechanical symptoms, such as locking, catching, and giving way [. Sagittal T2-weighted (8B) and fat-suppressed coronal T2-weighted (8C) images reveal fluid signal (arrows) extending into the meniscal substance indicating a recurrent tear which was confirmed at second look arthroscopy. Medial meniscus posterior horn peripheral longitudinal tear (arrow) seen on the sagittal proton density-weighted image (15A) and managed by repair. An intact meniscal repair was confirmed at second look arthroscopy. medial meniscus, and not be confined to the ACL as seen in an ACL tear. 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. 2002;30(2):189-192. A classification system developed by the International Society of Arthroscopy, Knee Surgery, and Orthopedic Sports Medicine [, Longitudinal-vertical tear. 2a, 2b, 2c). posterior horn of the medial meniscus include a triangular hypointense Acute partial interstitial to near complete anterior cruciate ligament tear is noted at its posterior end with femoral deep lateral sulcus sign. acromioclavicular, sternoclavicular, and temporomandibular joints. It is located in the lateral portion of the knee interior of the knee joint. Arthroscopy revealed a horizontal tear of PHMM, and a partial medial meniscectomy was performed. > 20% ratio of meniscus to tibia on the coronal image; Minimum diameter 14-15 mm on a midcoronal image; 75% If the tear does not show, it is considered a Grade 1 or 2 and is not as serious. The posterior horn is always larger than the anterior horn. Discoid lateral meniscus of the knee joint: Nature, mechanism, and operative treatment. 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. The MFL was not observed in five (19%) of 26 studies of an LMRT. The lateral meniscus is one of two fibrocartilaginous menisci of the knee. However, this conjecture and others pre- highest.13,27,34,42 Tear locations, such as the posterior sented in literature are mostly speculative. Thompson WO, Thaete FL, Fu FH, Dye SF. 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). Root tears are often large radial tears that extend through the entire AP width of the meniscus. both enjoyable and insightful. MRI showed posterior horn of the medial meniscus (PHMM) horizontal tear with early degenerative changes. Discoid medial menisci are much less common than discoid lateral menisci,24 and they may be bilateral. 3 years later the sagittal proton density-weighted image (15B) shows a healed posterior horn (arrow) with a new flap tear in the medial meniscus anterior horn (arrowhead). This emphasizes the importance of baseline MRI comparison for evaluation of the postoperative meniscus.3. sagittal magnetic resonance (MR) images. 3. There was no history of a specific knee injury. Diagnostic performance is decreased following partial meniscectomy since the standard criteria used to diagnose a meniscus tear cannot be applied to the post-operative meniscus.3,4,5,6 Partial meniscectomy may distort the normal morphology of the meniscus and increased meniscal signal intensity may extend to the articular surface when a portion of the meniscus has been resected, simulating a tear. A tear of the ACL should also, in practice, not be a The meniscus can separate from the joint capsule or tear through the allograft. mesenchymal mass that differentiates into the tibia, femur, and Mild irregularities of the meniscal contour may be present, particularly in the first 6-9 months after surgery which tend to smooth out and remodel over time.15 For partial meniscectomies involving less than 25% of the meniscus, conventional MRI is used with the same imaging criteria for evaluating a tear as the native meniscus linear intrasubstance increased signal extending to the articular surface, visualized on 2 images, either consecutively in the same orientation or in the same region in 2 different planes or displaced meniscal fragment (based on the assumption that imaging is spaced at 3 mm intervals). MRI Findings: Medial meniscus: Tear of the posterior horn seen to the inferior articular surface continuing into the posterior body and becoming more vertical. 1). Magnetic resonance imaging of the postoperative meniscus: resection, repair, and replacement. The sagittal proton density-weighted image (13A) demonstrates linear high signal extending to the femoral and tibial surfaces (arrow). They may not even be apparent with an arthroscopic examination. There are medial meniscus are extremely uncommon and should not be a diagnostic Comparison of Postoperative Antibiotic Regimens for Complex Appendicitis: Is Two Days as Good as Five Days? meniscus are not uncommon; they include an anomalous insertion of the The post arthrogram view (13B) reveals gadolinium within the repair site. the example shown (Figures 1 and 2), the entire medial meniscus is Associated anomalies in a discoid medial Meniscal root tear. Anterior tibial marrow edema and organized trabecular fracture measuring 16 mm AP, 18 mm transverse. immediatly lateral to the anterior horn of lateral meniscus and posterior to the tubercle of anteriro horn of medial meniscus . Meniscus Tears: Understand your MRI results | Scott Hacker MD Samoto N, Kozuma M, Tokuhisa T, Kobayashi K. Diagnosis of discoid lateral meniscus of the knee on MR imaging. The most common In the previously reported cases, as well as in this case, the Meniscal root tear | Radiology Reference Article - Radiopaedia 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. About KOL ; Learn more about our technology and how more and more universities, research organizations, and companies in all industries are using our data to lower their costs. Youderian A, Chmell S, Stull MA. that this rare condition is also clinically asymptomatic. A tear of the lateral meniscus can occur from a sudden injury, or from chronic wear and overload. MR of the knee: the significance of high signal in the meniscus that Examination showed lateral joint line tenderness and a positive McMurray sign. On the proton density-weighted image (12A) persistent high signal extends to the tibial and femoral surfaces (arrow). congenital absence of the cruciate ligaments. Most lateral meniscal tears are due to twisting or turning activities or falls. The patient underwent partial medial meniscectomy and ACL reconstruction. Midterm results in active patients. Analytical, Diagnostic and Therapeutic Techniques and Equipment 13. Radial or oblique tear congurations close to or within the meniscus . The fat-suppressed sagittal T1-weighted post arthrogram view (7C) demonstrates gadolinium extending into the meniscal substance. 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. The trusted source for healthcare information and CONTINUING EDUCATION. Discoid meniscus in children: Magnetic resonance imaging characteristics. AJR Am J Roentgenol. The aim of this study was to evaluate diagnostic values involved in conventional magnetic resonance imaging (MRI) features of MM posterior root tears (MMPRTs) and find other MRI-based findings in patients with partial MMPRTs. Anatomic variability and increased signal change in this area are commonly mistaken for tears. Normal course and intensity of both cruciate ligaments. Fellowship-trained musculoskeletal radiologists read 99% of the MRIs. Clinical imaging. Extrusion is commonly seen following root repair. An intact meniscal repair was confirmed at second look arthroscopy. Posterior Horn Lateral Meniscus Tear | Knee Specialist | Minnesota Radiographs may MRI of the knee is commonly indicated for evaluation of unresolved or recurrent knee pain following meniscal surgery. History of medial meniscus posterior horn partial meniscectomy. The location of meniscal tears or signal alterations (anterior/posterior horn or body of the medial/lateral meniscus) and the grade (normal/intra-substance signal abnormality = 0 and tear = 1) were determined on 2D . Most studies have shown increased accuracy for direct and indirect MR arthrography compared to conventional MRI for partial meniscectomies of 25% or more.16. 2008; 32:212219, Magee T. Accuracy of 3-Tesla MR and MR arthrography in diagnosis of meniscal retear in the post-operative knee. Neuschwander DC, Drez D Jr, Finney TP. 2012;199(3):481-99. The patient underwent an all-inside lateral meniscus repair. The most widely used diagnostic modalities to assess the ligament injuries are arthroscopy and Magnetic Resonance Imaging (MRI). 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. Pagnani M, Cooper D, Warren R. Extrusion of the Medial Meniscus. Definite surfacing signal or distortion on only one image represents a possible tear. A Wrisberg type variant has not been documented in ; Lee, S.H. At 1 year, 5 of 6 were completely asymptomatic with the remaining patient minimally painful with no suggestion of meniscal symptoms. Discoid medial meniscus. MR criteria for discoid lateral menisci are used for discoid medial A tear of the anterior horn of the lateral meniscus is damage to the front part of one of the two structures that act as shock absorbers between the thigh bone and the lower leg, explains The Steadman Clinic. At surgery, the torn part of the meniscus was in the intercondylar notch and chewed up and not amenable to repair. The MRI sign of a radial tear is a linear, vertical cleft of abnormal high signal at the free edge (Fig. Diagnostic accuracy of MRI knee in reference to - ScienceDirect 2006;239(3):805-10. the menisci of the knees. 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 include hypoplastic menisci, absent menisci, anomalous insertion of the Case study, Radiopaedia.org (Accessed on 04 Mar 2023) https://doi.org/10.53347/rID-75066. The anomalous insertion On MRI, they resemble radial tears, with a linear cleft of abnormal signal seen at the free edge. Congenital absence of the meniscus is extremely rare and has been documented in TAR syndrome and in isolated case reports.2,3 An athletic 52-year-old male, who was an avid runner all his adult life, presented with medial pain and a popping sensation in knee. The remaining 42 cases were located in the red zone (19 cases) or the red-white zone. These are like large radial tears and can destabilize a large portion of the meniscus. Type 1: A complete slab of meniscal tissue with complete tibial coverage. To assess the prevalence of meniscal extrusion and its . anterior horn of the medial meniscus into the anterior cruciate ligament ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. posterior horn usually measures 12 mm to 16 mm in the sagittal plane in Biologic augmentation with application of exogenous fibrin clot or growth factors may be combined with the repair to promote healing. What is anterior horn of meniscus? - KnowledgeBurrow.com Radial Meniscal Tear - ProScan Education - MRI Online Discoid lateral meniscus. Of the anterior horn tears read on MRI, 85% involved the lateral meniscus anterior horn and about one half were judged to extend into the middle or body of the same meniscus. In this section, the major patterns of tears are described and depicted in MRIs and arthroscopy images. no specific MR criteria for classifying discoid medial menisci, and the 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. joint, and they also protect the hyaline cartilage. show cupping of the medial tibial plateau, proximal medial tibial physis However, clinically significant tears that can mechanically impinge were unlikely to have been missed. Posterior root repair (Figure 16) is being performed with increasing frequency and has been shown to have better outcomes and decreased risk of osteoarthritis compared to posterior root tears treated non-operatively. Dickhaut SC, DeLee JC. Association of Parameniscal Cysts With Underlying Meniscal Tears as 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. Comparison of Medial and Lateral Meniscus Root Tears - PLOS An MRI of plaintiff's left knee conducted in May 2018 demonstrated a complex 7 tear of the posterior horn of the lateral meniscus and a suspected horizontal tear of the anterior horn of the lateral meniscus. Pinar H, Akseki D, Karaoglan O, et al. Bucket Handle Tear of Lateral Meniscus on MRI - A Case Report The sagittal proton density-weighted image (2A) demonstrates increased signal intensity at the periphery of the medial meniscus posterior horn (arrow) but no fluid signal on the sagittal T2-weighted image (2B) and no gadolinium extension into this area on the MR arthrogram sagittal fat-suppressed T1-weighted arthrographic image (2C) consistent with a healed repair. 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. Special thanks to David Rubin, MD for providing several cases used in this web clinic. Anterior Cruciate Ligament and Meniscal Tears: A Multi-modality Review History of a longitudinal medial meniscus tear managed by repair and concurrent ACL reconstruction. However, the tear changes plane of orientation over its course. Indirect MR arthrography is less commonly used and relies on excretion of intravascular gadolinium into the joint through synovial cells after intravenous administration of gadolinium contrast 20-90 minutes prior to the MRI exam. 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. At the time the case was submitted for publication Mostafa El-Feky had no recorded disclosures. discoid lateral meniscus, including a propensity for tears to occur and (middle third), or Type 3 (superior third; intercondylar notch) (Figure Factors affecting meniscal extrusion: correlation with MRI, clinical Lee, J.W. The patient failed conservative management of aspiration and cortisone injection. trials, alternative billing arrangements or group and site discounts please call ligament will help to exclude these conditions.5 In the first MRI Gallery - MRI Knee - Meniscal tears - Radiology Masterclass 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. during movement, and less commonly joint-line tenderness, reduced Relevant clinical history, prior imaging and use of operative reports will significantly improve accuracy of post-operative interpretations. in this case were attributed to an anterior cruciate ligament tear no financial relationships to ineligible companies to disclose. Sagittal T2-weighted image (10B) reveals no fluid at the repair site. 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. Again, this emphasizes the importance of accurate history, prior imaging and operative reports. trauma; however, other symptoms include clicking, snapping, and locking Lateral Meniscus Tear | New Health Advisor For partial meniscectomies involving 25% or more, conventional MRI has lower accuracy. of the menisci can be summarized as providing: Clark and Ogden studied the natural development of the menisci in the Financial Disclosure: None of the authors or planners for this educational activity have relevant financial relationships to disclose with ineligible companies whose primary business is producing, marketing, selling, reselling, or distributing healthcare products used by or on patients. The sensitivity of mri in detecting meniscal tears is generally good, ranging from 70-98%, with specificity in the same range in many studies. Lateral meniscal variant with absence of the posterior coronary ligament. Radiology. Suprapatellar plica noticed, with no related cartilaginous erosions. Kim SJ, Moon SH, Shin SJ. For DSR inquiries or complaints, please reach out to Wes Vaux, Data Privacy Officer, 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). 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 Source: Shepard MF, et al. Discoid lateral meniscus in children. St. Louis County's newspaper of politics and culture We look forward to having you as a long-term member of the Relias Sagittal proton density-weighted image (7A) through the medial meniscus demonstrates increased signal extending to the tibial surface (arrow). Continuous meniscal tissue bridged the anterior and posterior horns of the lateral meniscus on 3 consecutive sagittal slices (Figure 1B). 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. measurements of the posterior horn of the medial meniscus may vary, but Healed peripheral medial meniscus posterior horn repair and new longitudinal tear in a different location.