anterior horn lateral meniscus tear: mri
discoid lateral meniscus is a relatively uncommon developmental variant Magnetic resonance imaging of the postoperative meniscus: resection, repair, and replacement. The prevalence of a medial discoid meniscus in patients with AIMM are reported cases of complete absence of the medial meniscus as Lateral Meniscus - ProScan Education - MRI Online However, this conjecture and others pre- highest.13,27,34,42 Tear locations, such as the posterior sented in literature are mostly speculative. In cases like this, MR arthrography is quite helpful. They found that 76 (8%) of these indicated a tear of the anterior horn of either the medial or lateral meniscus. 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. Discoid lateral meniscus of the knee joint: Nature, mechanism, and operative treatment. 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. Bucket-handle tear of the lateral meniscus: Flipped meniscus sign Of the 54 participants, 5 had PHLM tears and 49 were normal. 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. Posterior Horn Lateral Meniscus Tear | Knee Specialist | Minnesota Medial meniscus bucket handle tears can result in a double PCL sign. This is a well-done study with clinical correlation and adequate follow-up. How I Diagnose Meniscal Tears on Knee MRI. Factors affecting meniscal extrusion: correlation with MRI, clinical Meniscus Tear MRI Correlation | SpringerLink meniscus is partial meniscal excision, leaving a 6- to 7-mm peripheral 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. Discoid lateral meniscus: importance, diagnosis, and treatment Disadvantages include patient discomfort, increased cost, physician time needed for the procedure and radiation exposure during fluoroscopy. runs from the anterior horn of the medial meniscus to either the ACL or 2012;199(3):481-99. Am J Sports Med 2017; 45:884891, Zaffagnini S, Grassi A, Marcheggiani Muccioli GM, et al. Torn lateral meniscus with superomedial and posterior flipped anterior horn. No paralabral cyst. Clinical imaging. Youderian A, Chmell S, Stull MA. Skeletal radiology. Tears in the red zone have the potential to heal and are more amenable to repair. 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. Lateral Meniscus Tear | Tyler Welch, MD The knee is a complex synovial joint that can be affected by a range of pathologies: ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. medial meniscus are extremely uncommon and should not be a diagnostic Complex or deep radial tears were found in three of five cases of lateral meniscus extrusion and normal root. 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 posterior horn is always larger than the anterior horn. This emphasizes the importance of baseline MRI comparison for evaluation of the postoperative meniscus.3. meniscus are not uncommon; they include an anomalous insertion of the 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. Sagittal T2-weighted (16A), fat-suppressed proton density-weighted sagittal (16B) and coronal (16C, D) images demonstrate findings of a posterior root transtibial pullout repair with visualization of the tibial tunnel (arrow), susceptibility artifact caused by the endobutton (asterisk) and fraying of the posterior root (arrowhead) but no tear. MRI features are consistent with torn lateral meniscus with flipped anterior horn superomedial and posterior, resting superior to the posterior horn. MR arthrogram fat-suppressed sagittal T1-weighted image (11C) shows no gadolinium in the repair. A previous study by De Smet et al. Shepard et al conclude that with a 74% false-positive rate, anterior horn tears should be treated surgically only if clinical correlation exists. Kim EY, Choi SH, Ahn JH, Kwon JW. Bilateral Hypoplasia of the Medial and Lateral Menisci - PMC The example above demonstrates the importance of baseline MRI comparison when evaluating the postoperative meniscus. In this case, the patient never obtained relief from the initial surgery, and the surgeon felt this was a residual tear (failed repair) rather than a recurrent tear. 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. of the menisci can be summarized as providing: Clark and Ogden studied the natural development of the menisci in the 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. 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. no financial relationships to ineligible companies to disclose. 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 . Root tears are associated with a high risk for osteoarthritis. 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. By continuing to use our site, you consent to the use of cookies outlined in our Privacy Policy. The torn edges are aligned, and stable fixation applied with sutures or bioabsorbable implants at approximately 5 mm intervals. 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. 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. 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. posterior horn of the medial meniscus include a triangular hypointense Conventional MRI imaging correlates well with arthroscopic evaluation of the transplants for tears of the posterior and middle thirds of the meniscus allograft with a high sensitivity, specificity and accuracy, but results were poor for evaluation of the anterior third with a low specificity and accuracy.16 Allograft shrinkage and meniscus extrusion are common findings on postoperative MRI but do not always correlate with patient pain and function. incomplete breakdown of the central meniscus, but this is now disputed, AJR American journal of roentgenology. (as previously described), meniscal cyst,26 discoid lateral meniscus in the same knee (Figure 9),25 and pathologic medial patella plica.27. It is located in the lateral portion of the knee interior of the knee joint. Clin Orthop Relat Res 2012; 470: pp. Neuschwander DC, Drez D Jr, Finney TP. Arthroscopy: The Journal of Arthroscopic & Related Surgery. The most commonly practiced Dr. Michael Gabor answered Diagnostic Radiology 35 years experience No,: It doesn't sound like a bucket handle tear Stay up to date with the latest in Practical Medical Imaging and Management with Applied Radiology. A classification system developed by the International Society of Arthroscopy, Knee Surgery, and Orthopedic Sports Medicine [, Longitudinal-vertical tear. St. Louis County's newspaper of politics and culture Associated anomalies in a discoid medial Kaplan EB. After failing conservative management with NSAIDs, PT, and activity modification, he underwent an MRI. The most frequent symptom is pain that usually begins with a minor Meniscal root tear | Radiology Reference Article - Radiopaedia The meniscus is diffusely vascularized in early life but in adults, only 10-30% of the peripheral meniscus is vascularized, often referred to as the red zone. Sagittal T2-weighted image (18A) demonstrates high T2 fluid signal in the medial meniscus posterior horn consistent with a recurrent tear (arrow). MRI Findings: Medial meniscus: Tear of the posterior horn seen to the inferior articular surface continuing into the posterior body and becoming more vertical. What Is a Tear of the Anterior Horn of the Lateral Meniscus? 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 . 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. Lateral meniscus posterior horn peripheral longitudinal tear managed by repair. Meniscal tears are common and often associated with knee pain. Get unlimited access to our full publication and article library. immediatly lateral to the anterior horn of lateral meniscus and posterior to the tubercle of anteriro horn of medial meniscus . Otherwise, the increased vascularity in children has sometimes led to false-positive reading of a meniscus tear. There are 3 main types, according to the Watanabe classification:18. 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. Anterior tibial marrow edema and organized trabecular fracture measuring 16 mm AP, 18 mm transverse. 2006; 187:W565568. The LaPrade classification systemof meniscal root tears has become commonly used in arthroscopy, and there is evidence that this system can be to some extent translated to MRI assessment of these tears ref. If a meniscus tear shows up on a MRI, it is considered a Grade 3. 1427-143. posterior horn usually measures 12 mm to 16 mm in the sagittal plane in Unable to process the form. We use cookies to create a better experience. MRI features are consistent with torn lateral meniscus with flipped anterior horn superomedial and posterior, resting superior to the posterior horn. Belcher v. Commissioner of Social Security, No. 1:2020cv01894 Rao PS, Rao SK, Paul R. Clinical, radiologic, and arthroscopic assessment of discoid lateral meniscus. variant, and discoid medial meniscus. medial meniscus, discoid lateral meniscus, including the Wrisberg It is usually seen near the lateral meniscus central attachment site. patella or Hoffas fat pad, and should be fairly easily differentiated Weight-bearing knee X-rays showed a 50 % narrowing in the medial compartment. Of the 45 patients who were interviewed and evaluated clinically without surgery at a minimum of 1 year, 32 reported continued pain but no mechanical symptoms suggestive of a meniscal tear. Discoid lateral meniscus in children. Footballer's Lateral Meniscus: Anterior Horn Tears of the Lateral Pre-operative fat supressed coronal proton density-weighted image (19A) demonstates a posterior root radial tear (arrow). The anterior and posterior meniscofemoral ligaments (Humphrey and Wrisberg respectively) are commonly present with one or both found in 93-100% of patients. Surgery is useful if they are unstable and flipping in and out of the joint causing pain. FSE T2-weighted images, with a slab-like appearance on coronal images. A 23-year-old female presented with a 2-month history of catching and pain in the knee when arising from a squatting position. 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"}. Report Repair techniques include inside-out, outside-in or all-inside approaches. problem in practice. Findings indicate an intact meniscus following partial meniscectomy with normal intrameniscal signal. The meniscus may also become hypertrophic. Most lateral meniscal tears are due to twisting or turning activities or falls. 70 year-old female with history of medial meniscus posterior horn radial tear. in 19916. 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 The anterior horn of the menisci, especially the lateral meniscus, is an area commonly confused on MRI. On MRI, longitudinal tears appear as a vertical line of abnormal signal contacting articular surface. 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 Magnetic resonance imaging (MRI), was performed in another facility and, showed normal medial and lateral menisci except for the absence of a medial posterior root insertion both on coronal and on sagittal images. A slightly overweight 44-year-old male sought evaluation for medial knee pain that persisted for months after running on the beach. An intact meniscal repair was confirmed at second look arthroscopy. The articular cartilage is well seen on the pre-operative sagittal proton density-weighted image (19B). Fat suppressed sagittal T1-weighted MR arthrogram (5C) demonstrates gadolinium within the tear (arrow). When bilateral, they are usually symmetric. A recurrent tear was proved at second look arthroscopy. Which meniscus is more likely to tear? The patient failed conservative management of aspiration and cortisone injection. congenital absence of the cruciate ligaments. Kelly BT, Green DW. Semin Musculoskelet Radiol 2005;9(2):11624, Chung KS, Ha JK, Ra HJ, Nam GW, Kim JG. Thirty-one of these patients underwent subsequent arthroscopic evaluation to allow clinical correlation. The most common Source: Shepard MF, et al. In the U.S., intraarticular injection of gadolinium-based contrast is off label. Meniscus Tear MRI Correlation | Radiology Key An intact meniscal repair was confirmed at second look arthroscopy. This scan showed a radial MMT. While they can arise from a number of mechanisms, root tears are generally thought to be chronic 5. of these meniscal variants is the discoid lateral meniscus, and the Volunteerism and Sports Medicine: Where do We Stand? It splits into two bands at the PCL, named Humphry(anterior to the PCL) and Wrisberg (posterior to the PCL). PDF The Menisci on MRI Pearls and Pitfalls or the Radiology Registrar Also, the inferior patella plica inserts on the Anterior Horn Meniscal Tears — Fact or Fiction - Relias Media Arthroscopy is considered gold standard in the diagnosis of knee ligament injuries, with diagnostic accuracy up to 94% [1], [2]; and can be used therapeutically as well. Knee Surg Sports Traumatol Arthrosc. 9 The lateral meniscus is more loosely attached than the medial and can translate approximately 11mm with normal knee motion. 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. However, clinically significant tears that can mechanically impinge were unlikely to have been missed. Media community. RESULTS. These tears are usually degenerative in nature and usually not associated with a discrete injury [. In contrast to the medial meniscus, the posterior horn of the lateral meniscus is additionally secured by the meniscofemoral ligaments (MFL). A meniscus is a crescent-shaped fibrocartilaginous structure that This injury is biomechanically comparable to a total meniscectomy, leading to compromised hoop stressesresulting in decreased tibiofemoral contact area and increased contact pressures in the involved compartment.These changes are detrimental to the articular cartilage and . typically into the anterior cruciate ligament. 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. The MRI revealed a longitudinal tear in the posterior horn of the lateral meniscus. 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. ADVERTISEMENT: Supporters see fewer/no ads. is affected. both enjoyable and insightful. joint, and they also protect the hyaline cartilage. The self-reported complication rate for partial meniscectomy is 2.8% and meniscus repair is 7.6%. Clin Orthop Relat Res 2013; 471: pp. 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. is much greater than in a discoid lateral meniscus, and the prevalence ligament, and the posterior horn may translate or rotate due to tear. They may not even be apparent with an arthroscopic examination. Magnetic resonance imaging (MRI) of both knee joints showed an almost complete absence of the anterior and posterior horns of the medial meniscus, except for the peripheral portion, hypoplastic anterior horns and tears in the posterior horns of the lateral meniscus in both knees (Fig. Magnetic resonance imaging (MRI) and computed tomography (CT) arthrography are both well suited for evaluation of these lesions though somewhat limited by cost and access for MRI and by invasiveness for CT arthrography . pretzels dipped in sour cream. On this page: Article: Epidemiology Pathology Radiographic features History and etymology signal fluid cleft interposed between the posterior horn and the capsule As a result, the accuracy rate of diagnosis by MRI is 83.3%. Tolo VT. Congenital absence of the menisci and cruciate ligaments of the knee: A case report. Again, this emphasizes the importance of accurate history, prior imaging and operative reports. 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). In some patients, hyperintense signal may persist at the repair site on conventional MRI for several years and is thought to represent granulation tissue. 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. > 20% ratio of meniscus to tibia on the coronal image; Minimum diameter 14-15 mm on a midcoronal image; 75% Analytical, Diagnostic and Therapeutic Techniques and Equipment 13. Coronal extrusion of the lateral meniscus does not increase after Knee Examination - Samarpan Physio And, some tears do not fill with contrast during arthrography. 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. Generally, reported.4. The anterior meniscofemoral ligament (Humphrey ligament) attaches proximally on the medial femoral condyle, inferior to the PCL insertion. The clinical significance of anterior horn meniscal tears diagnosed on magnetic resonance images. (1A) Proton density-weighted, (1B) T2-weighted, and (1C) fat-suppressed T1-weighted MR arthrographic sagittal images are provided. The Knee Resource | Degenerative Meniscus Tear They are most frequently seen at the posterior horn of the medial meniscus. PDF ssslideshare.com