The MRI sign of a radial tear is a linear, vertical cleft of abnormal high signal at the free edge (Fig. Longitudinal medial meniscus tear managed by repair (arrow). MRI features are consistent with torn lateral meniscus with flipped anterior horn superomedial and posterior, resting superior to the posterior horn. Each meniscus has three main parts, the back (posterior horn), middle (body), and front (anterior horn). They often tend to be radial tears extending into the meniscal root. 1. Interested in Group Sales? was saddle shaped. Again, this emphasizes the importance of accurate history, prior imaging and operative reports. Discoid lateral meniscus of the knee joint: Nature, mechanism, and operative treatment. hypermobility. Examination showed lateral joint line tenderness and a positive McMurray sign. It is located in the lateral portion of the knee interior of the knee joint. Pathology - a tear that has developed gradually in the meniscus. this may extend to to the mid body." is this a bucket tear? Stein T, Mehling AP, Welsch F, von EisenhartRothe R, Jger A. Of these patients treated nonoperatively, 6 had a diagnosis of an isolated anterior horn tear on MRI. Shepard et al have done a nice job of telling us just how frequently this mistake can be made by fellowship trained musculoskeletal radiologists. ligament and meniscal fascicles. Radiology. of the anterior horn of the medial meniscus, an inferior patella plica, ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. 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. bilaterally absent menisci reported by Tolo et al,3 the A recurrent tear was proved at second look arthroscopy. posterior horn of the medial meniscus include a triangular hypointense It splits into two bands at the PCL, named Humphry(anterior to the PCL) and Wrisberg (posterior to the PCL). MR imaging is useful for evaluation of many possible complications following meniscal surgery. 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. A tear of the ACL should also, in practice, not be a Medial meniscus posterior horn peripheral longitudinal tear treated with repair. Disadvantages include patient discomfort, increased cost, physician time needed for the procedure and radiation exposure during fluoroscopy. hypoplastic meniscus was not the cause of the patients pain, suggesting Discoid medial meniscus. Klingele KE, Kocher MS, Hresko MT, et al. CT arthrography is recommended for patients with MRI contraindications or when extensive susceptibility artifact from hardware obscures the meniscus. A slightly overweight 44-year-old male sought evaluation for medial knee pain that persisted for months after running on the beach. 2006;239(3):805-10. MR imaging and MR arthrography for diagnosis of recurrent tears in the postoperative meniscus. 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 Anterior horn lateral meniscus tear A female asked: Mri: "macerated anterior horn lateral meniscus with inferiorly surfacing tear. This article focuses on The posterior root lies anterior to the posterior cruciate ligament. Additionally, the postoperative complication of new extensive synovitis is apparent on the axial view (18D). Proper preoperative sizing of the allograft is critical for surgical success and usually performed with radiographs. The trusted source for healthcare information and CONTINUING EDUCATION. Root tears are often large radial tears that extend through the entire AP width of the meniscus. problem in practice. noted to be diminutive, with the posterior horn measuring 7 mm to 8 mm. What is a Lateral Meniscus Tear? 3 is least common. mimicking an anterior horn tear. meniscus is partial meniscal excision, leaving a 6- to 7-mm peripheral 800-688-2421. 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. 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. 10 70 year-old female with history of medial meniscus posterior horn radial tear. 1 ). Magnetic Resonance Imaging Arthroscopy Orthodontic Extrusion Anterior Cruciate Ligament Reconstruction Arthroscopes Suture Anchors Tissue Culture Techniques Tissue Engineering Injections, Intra-Articular Range of Motion, Articular Arthrography Hardness Tests Orthopedic Procedures Associated anomalies in a discoid medial 2006; 187:W565568. Meniscal transplant is usually reserved for patients younger than 50 years who have normal axial alignment. 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. Both horns of the medial meniscus are triangular with sharp points. Diagnosis of recurrent meniscal tears: prospective evaluation of conventional MR imaging, indirect MR arthrography, and direct MR arthrography. And, some tears do not fill with contrast during arthrography. Davidson D, Letts M, Glasgow R. Discoid meniscus in children: Treatment and outcome. Lateral meniscus posterior horn peripheral longitudinal tear managed by repair. Sagittal T2-weighted image (18A) demonstrates high T2 fluid signal in the medial meniscus posterior horn consistent with a recurrent tear (arrow). What causes abnormal mobility in the medial meniscus? Concise, to-the-point text covers MRI for the entire musculoskeletal system, presented in a highly templated format. . Presentation - Middle-older aged individuals, non-traumatic, progressive onset of pain. History of medial meniscus posterior horn partial meniscectomy. The ends of the anterior and posterior horns are firmly attached to the tibia at their roots. 1). with mechanical features of clicking and locking. Medial meniscus posterior horn peripheral longitudinal tear (arrow) seen on the sagittal proton density-weighted image (15A) and managed by repair. MRI Knee - Sagittal PDFS - Displaced meniscus Part of a torn meniscus can be displaced into another part of the knee joint In this image the anterior part of the meniscus (the anterior horn) is correctly located The posterior horn is displaced such that it is located next to the anterior horn The correct position of the posterior horn is shown collapse and widening of the medial joint space (Figure 7). 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 most important clinical concern at the time of MRI imaging is often high-grade articular cartilage loss. Bilateral hypoplasia of the medial meniscus has also been A Study of Retrieved Allografts Used for ACL Surgery, Long-Term Results of Meniscus Allograft Transplantation with Concurrent ACL Reconstruction, Anterior Horn Meniscal Tears — Fact or Fiction, How Triathletes Can Use Cycling Cadence to Maximize Running Performance, Pharmacology Watch: HRT - Position Paper Places Benefits in Question, Clinical Briefs in Primary Care Supplement. that this rare condition is also clinically asymptomatic. Unable to process the form. However, few studies have directly compared the medial and lateral root tears. You have reached your article limit for the month. A meniscus is a crescent-shaped fibrocartilaginous structure that Discoid meniscus in children: Magnetic resonance imaging characteristics. 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. This is because most tears occur in the posterior horns [, Whether a torn meniscus is reparable depends on the type or pattern of tear, its location, and the quality of the meniscal tissue. MRI appearance of Wrisberg variant of discoid lateral meniscus. With age, increased connective tissue stiffness of the meniscus develops secondary to elastin degradation and collagen rigidification.2. appearance.12 It is now believed that the knee develops from a Check for errors and try again. It is usually seen near the lateral meniscus central attachment site. Radiographs are usually not diagnostic, but they may show a during movement, and less commonly joint-line tenderness, reduced 2012;199(3):481-99. 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. rim circumferentially, anteriorly, and posteriorly,19 which 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). The posterior cruciate ligament is intact. Comparison of Postoperative Antibiotic Regimens for Complex Appendicitis: Is Two Days as Good as Five Days? The Journal of bone and joint surgery American volume. One important reason for such discrepancies is a failure to understand the transverse geniculate ligament of the knee (TGL). Posteroinferior displacement of the meniscal tissue (arrowheads) is also diagnostic of recurrent tear. The medial compartment articular cartilage is preserved, and the meniscal body is not significantly extruded (16D). No gadolinium extension into the meniscus on fat-suppressed sagittal T1-weighted (9B) post arthrogram view. {"url":"/signup-modal-props.json?lang=us"}, El-Feky M, Flipped meniscus - anterior horn lateral meniscus. Kaplan EB. Singh K, Helms CA, Jacobs MT, Higgins LD. of the AIMM into the ACL is classified as Type 1 (inferior third), Type 2 This high rate of success, however, may not apply to anterior horn tears, which occur much less commonly than posterior horn and meniscal body tears. CT arthrography may be used to evaluate the postoperative meniscus when MRI is contraindicated. Schwenke M, Singh M, Chow B Anterior Cruciate Ligament and Meniscal Tears: A Multi-modality Review. The shape of the meniscus is formed at the eighth week of Connolly B, Babyn PS, Wright JG, Thorner PS. 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. Pagnani M, Cooper D, Warren R. Extrusion of the Medial Meniscus. Kijowski et al. medial meniscus are extremely uncommon and should not be a diagnostic treatment for stable complete or incomplete types of discoid lateral 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. mobility, and a giving-way sensation.11, 15, 16 A high percentage of cases present with an associated meniscal tear and peripheral rim instability.9,16,17 Although discoid lateral meniscus is commonly bilateral, symptoms tend to occur on one side.15 It is characterized by an excess of meniscal tissue with a slab-like configuration in the 2 most common forms (Figure 5). Type 1: A complete slab of meniscal tissue with complete tibial coverage. 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. This emphasizes the importance of meniscal repair over meniscectomy when possible and the need for meniscal preservation when a partial meniscectomy is necessary. A displaced longitudinal tear is a "bucket handle" tear. occur with minor trauma. 1991;7(3):297-300. View Mostafa El-Feky's current disclosures, see full revision history and disclosures, Flipped meniscus - anterior horn lateral meniscus, Disproportionate posterior horn sign (meniscal tear). Disadvantages include risks associated with joint injection, radiation exposure and lower contrast resolution compared to MRI, particularly in the extraarticular soft tissues. 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 [. Anterior lateral cysts extended . Diagnosis - clinical presentation with exclusion of advanced knee osteoarthritis. Laundre BJ, Collins MS, Bond JR, Dahm DL, Stuart MJ, Mandrekar JN: MRI accuracy for tears of the posterior horn of the lateral meniscus in patients with acute anterior cruciate ligament injury and the clinical relevance of missed tears. The avulsed anterior horn of the lateral meniscus is flipped over and situated above the posterior horn. menisci (Figure 8). gestation, about the time when the knee joint is fully formed.1 Throughout fetal development, they found that the size of the lateral meniscus is highly variable, unlike the medial meniscus. Grades 1 and 2 are not considered serious. The prevalence of a medial discoid meniscus in patients with AIMM The medial meniscus is asymmetrical with a larger posterior horn. It is believed that discoid Sagittal proton density-weighted image (8A) through the medial meniscus demonstrates signal extending to the tibial surface (arrow). Lateral meniscal variant with absence of the posterior coronary ligament. horn of the lateral meniscus, and oblique tear orientation In the present study, the patients analyzed came from the have been the most difficult for imaging planes to visualize same geographical area . Problems encountered in a discoid medial meniscus are the same as a Semin Musculoskelet Radiol 2005;9(2):11624, Chung KS, Ha JK, Ra HJ, Nam GW, Kim JG. On MR arthrography, (12B), gadolinium extends through the repair site indicating a tear. Anatomic variability and increased signal change in this area are commonly mistaken for tears. In cases like this, MR arthrography is quite helpful. Shepard and colleagues at UCLA specifically analyzed this by reviewing 947 consecutive MRIs. Among these 26 studies of an LMRT . The discoid lateral-meniscus syndrome. Fellowship-trained musculoskeletal radiologists read 99% of the MRIs. 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. Controlling Blood Pressure During Pregnancy Could Lower Dementia Risk, Researchers Address HIV Treatment Gap Among Underserved Population, HHS Announces Reorganization of Office for Civil Rights, FDA Adopts Flu-Like Plan for an Annual COVID Vaccine. Twenty-one had ACL tears; all those with an PHLM tear had an ACL tear. The lateral meniscus is produced by the varus tension and tibial IR. are reported cases of complete absence of the medial meniscus as Sagittal T2-weighted (18B) and fat-suppressed sagittal proton density-weighted sagittal (18C) images demonstrate fluid-like signal in the posterior horn suggestive of a recurrent tear. incomplete breakdown of the central meniscus, but this is now disputed, MRI failed to detect anterior horn injury of lateral meniscus in six (16.7%) cases, all of which were longitudinal fissure in the red zone. joint: Morphologic changes and their potential role in childhood Copy. ligament, and the posterior horn may translate or rotate due to Sagittal T2-weighted image (10B) reveals no fluid at the repair site. Dr. Diduch, Associate Professor, Department of Orthopaedic Surgery, University of Virginia School of Medicine, Charlottesville, VA, is Editor of Sports Medicine Reports. MR arthrogram fat-suppressed sagittal T1-weighted image (11C) shows no gadolinium in the repair. Radial Meniscal Tear: Pearls May be degenerative or traumatic, vertical, millimeters in size, on the inner edge of the lateral meniscus more commonly than the medial meniscus This is a critical differentiation because the latter represents meniscal tears that can be Lateral meniscus tears of the posterior root are a common concomitant injury to anterior cruciate ligament (ACL) tears [6, 16, 20]. Become a Gold Supporter and see no third-party ads. Increased intrameniscal signal is commonly seen in the transplanted allograft but does not correlate with clinical outcome. tissue only persists at the edges, where differentiation into the of the transverse ligament is comparable to the general population.5. Meniscal tears are common and often associated with knee pain. 9 The lateral meniscus is more loosely attached than the medial and can translate approximately 11mm with normal knee motion. Figure 7: Meniscofemoral ligament. Clinical History: An 18 year-old male with a history of a posterior horn medial meniscus peripheral longitudinal tear treated with meniscal repair at age 16 presents for MR imaging. is in fact reducing the volume of the meniscus and restoring a normal Rohren EM, Kosarek FJ, Helms CA. The example above illustrates marked degenerative changes caused by loss of meniscal function. Reference article, Radiopaedia.org (Accessed on 04 Mar 2023) https://doi.org/10.53347/rID-40036, {"containerId":"expandableQuestionsContainer","displayRelatedArticles":true,"displayNextQuestion":true,"displaySkipQuestion":true,"articleId":40036,"questionManager":null,"mcqUrl":"https://radiopaedia.org/articles/meniscal-root-tear/questions/1112?lang=us"}. structure on sagittal images on T1, proton density, and fat-saturated ligaments and menisci causing severe knee dysplasia in TAR syndrome. No paralabral cyst. the intercondylar notch, most commonly to the mid ACL, and less commonly On MRI, they resemble radial tears, with a linear cleft of abnormal signal seen at the free edge. The post arthrogram view (13B) reveals gadolinium within the repair site. Kelly BT, Green DW. both enjoyable and insightful. Meniscal disorders: Normal, discoid, and cysts. 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? Dr. Michael Gabor answered Diagnostic Radiology 35 years experience No,: It doesn't sound like a bucket handle tear Menisci are present in the knees and the 2012;20(10):2098-103. However, many clinicians opt to use conventional MRI as the initial postoperative imaging study and reserve MR arthrography for equivocal cases. Examination of the knee showed a mild effusion, 1+ Lachman, positive Pivot shift, and mild tenderness to both medial and lateral joint lines. Surgical Outcomes Lysholm Score MRI: When you tear your meniscus, a magnetic resonance imaging (MRI) scan will show the injury as white lines on black. 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. The lateral meniscus is more circular, and its anterior and posterior horns are nearly equivalent in size in cross section. To assess the prevalence of meniscal extrusion and its . (1A) Proton density-weighted, (1B) T2-weighted, and (1C) fat-suppressed T1-weighted MR arthrographic sagittal images are provided. Evaluate the TCO of your PACS download >, 750 Old Hickory Blvd, Suite 1-260Brentwood, TN 37027, Focus on Musculoskeletal and Neurological MRI, Meniscal tears: the effect of meniscectomy and of repair on intraarticular contact areas and stress in the human knee. When interpreting MR images of the knee, it is important to assess for any change from the expected shape of the menisci. In the previously reported cases, as well as in this case, the Clin Orthop Relat Res 2012; 470: pp. MRI Findings: Medial meniscus: Tear of the posterior horn seen to the inferior articular surface continuing into the posterior body and becoming more vertical. Complex or deep radial tears were found in three of five cases of lateral meniscus extrusion and normal root. My own experience has been similar and I make it a policy not to recommend surgery based on this diagnosis alone without good clinical correlation. The self-reported complication rate for partial meniscectomy is 2.8% and meniscus repair is 7.6%. is much greater than in a discoid lateral meniscus, and the prevalence When the cruciate 36 year old male with history of meniscus surgery 7 years ago. A published a case series of anterior horn tears of the lateral meniscus in 14 soccer players (mean age 20.2 years). {"url":"/signup-modal-props.json?lang=us"}, Weerakkody Y, Baba Y, Knipe H, et al. Because this is a relatively new procedure, few studies have been dedicated to MRI evaluation of postoperative root repair. seen on standard 4- to 5-mm slices.21 The Wrisberg ligament may also be thick and high in patients with a complete discoid lateral meniscus.22 Other criteria used to diagnose lateral discoid meniscus include the following: In the 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. is affected. Create a new print or digital subscription to Applied Radiology. Type 1 is most common, and type 2013;106(1):91-115. in 19916. Papalia R, Vasta S, Franceschi F, D'Adamio S, Maffulli N, Denaro V. Meniscal Root Tears: From Basic Science to Ultimate Surgery. Both the healed peripheral tear and the new central tear were proved at second look arthroscopy. We use cookies to create a better experience. The ligament of Humphrey inserted on average 0.9 consecutive images lateral to the PCL without an PHLM tear and 4.7 with an PHLM tear; the ligament of Wrisberg inserted on average 3.0 consecutive images without an PHLM tear and 4.5 with an PHLM tear . Materials and methods . for the ratio of the sum of the width of the anterior and posterior Wrisberg variant, the morphology of the meniscus may be normal, but the 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. At the time the article was created Yuranga Weerakkody had no recorded disclosures. 2002; 222:421429, Ciliz D, Ciliz A, Elverici E, Sakman B, Yuksel E, Akbulut O. What is a Grade 3 meniscus tear? 7 Therefore, it is important for the radiologist to be familiar with the appearance of a recurrent tear versus an untorn postoperative meniscus. They were first described by M J Pagnaniet al. 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. ADVERTISEMENT: Supporters see fewer/no ads. 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. (as previously described), meniscal cyst,26 discoid lateral meniscus in the same knee (Figure 9),25 and pathologic medial patella plica.27. Radial tears comprise approximately 15 % of tears in some surgical series [. Seventy-four cases of bucket-handle tears (mean age, 27.2 11.3 years; 38 medial meniscus and 36 lateral meniscus; 39 concomitant anterior cruciate ligament (ACL) reconstruction) were treated with arthroscopic repair from June 2011 to August 2021. The insertion site Anatomic variability and increased signal change in this area are commonly mistaken for tears. and ACL tears can be mistaken for AIMM, but carefully tracing the ligaments are absent, most commonly the anterior cruciate ligament (ACL) The most widely used diagnostic modalities to assess the ligament injuries are arthroscopy and Magnetic Resonance Imaging (MRI). Arthroscopy: The Journal of Arthroscopic & Related Surgery. Brody J, Lin H, Hulstyn M, Tung G. Lateral Meniscus Root Tear and Meniscus Extrusion with Anterior Cruciate Ligament 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 There are 3 main types, according to the Watanabe classification:18. The meniscus may also become hypertrophic. 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. On the sagittal fat-suppressed T2-weighted image (7B), fluid extends into the tear. Biologic augmentation with application of exogenous fibrin clot or growth factors may be combined with the repair to promote healing. During an arthroscopy, we have the choice of either repairing the meniscus tear or removing the torn piece. Total meniscectomy is rarely performed unless the meniscus is so severely damaged that no salvageable meniscal tissue remains. Another MRI was later performed due to worsening symptoms, and demonstrated a bucket-handle tear with complete anterior luxation of the posterior horn of the left lateral meniscus (Figs. The patient underwent meniscal repair but had recurrent pain prompting repeat MRI 8 months post-operative. 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 . MRI features are consistent with torn lateral meniscus with flipped anterior horn superomedial and posterior, resting superior to the posterior horn. signal fluid cleft interposed between the posterior horn and the capsule trauma; however, other symptoms include clicking, snapping, and locking . Pain is typically medial and activity-related (e.g. frequently. Stay up to date with the latest in Practical Medical Imaging and Management with Applied Radiology. Description. It has been calculated that the lateral meniscus absorbs about 70% of the forces across the lateral compartment of the knee. It can be divided into five segments: anterior horn, anterior, middle and posterior segments, and posterior horn. asymptomatic, although there is a greater propensity for discoid menisci Meniscal transplants can fail at the implantation site by avulsion, failure of bone plug incorporation or bone bridge fracture. show cupping of the medial tibial plateau, proximal medial tibial physis