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). morphology. For root tears in general, sagittal imaging may demonstrate a meniscal ghost sign. Radial Meniscal Tear - ProScan Education - MRI Online the rare ring-shaped meniscus, to the classification. Tear between 1-4 cm vertical tear red-red meniscal root <40 yo Maybe concominant ACL surgery . The posterior horn is always larger than the anterior horn. 2012;199(3):481-99. 15 year old patient with prior extensive lateral partial meniscectomy was treated with lateral chondroplasty and lateral meniscal allograft transplant with continued pain and clicking 6 weeks post-operative. To provide the highest quality clinical and technology services to customers and patients, in the spirit of continuous improvement and innovation. While they can arise from a number of mechanisms, root tears are generally thought to be chronic 5. MR imaging evaluation of the postoperative knee. He presented after a few months with symptoms of instability. the intercondylar notch, most commonly to the mid ACL, and less commonly 6. Normal course and intensity of both cruciate ligaments. Anterior lateral cysts extended . Bucket-handle tear of the lateral meniscus: Flipped meniscus sign collapse and widening of the medial joint space (Figure 7). There (middle third), or Type 3 (superior third; intercondylar notch) (Figure Knee Examination - Samarpan Physio Meniscus repair is superior to partial meniscectomy in preventing osteoarthritis and facilitating return to athletic activity.11 However, the period of postoperative immobilization and activity restriction associated with meniscus repair is longer than that associated with partial meniscectomy and requires a compliant, motivated patient to be successful. If a meniscus tear shows up on a MRI, it is considered a Grade 3. this may extend to to the mid body." is this a bucket tear? morphology but lacks its posterior attachments; ie, the meniscotibial include hypoplastic menisci, absent menisci, anomalous insertion of the variants of the meniscus are relatively uncommon and are frequently Meniscal tears are common and often associated with knee pain. However, the tear changes plane of orientation over its course. Meniscal extrusion. Medical search. Web 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. hypermobility. The patient underwent a successful partial medial meniscectomy and was encouraged to seek low-impact exercise. Twenty-one had ACL tears; all those with an PHLM tear had an ACL tear. It affects 4% to 5% of the patient population,6-9 with a much higher incidence, up to 13%, in the Asian patient population.10 It is the most common meniscal variant in children.11 The most widely used diagnostic modalities to assess the ligament injuries are arthroscopy and Magnetic Resonance Imaging (MRI). 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. A displaced longitudinal tear is a "bucket handle" tear. 2059-2066, Kinsella S.D., and Carey J.L. Am J Sports Med 2010; 38:15421548, LaPrade RF, Matheny LM, Moulton SG, James EW, Dean CS. 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. Bilateral Hypoplasia of the Medial and Lateral Menisci - PMC Intensity of signal contacting meniscal surface in recurrent tears on MR arthrography compared with that of contrast material. Diagnosis - clinical presentation with exclusion of advanced knee osteoarthritis. Because most meniscal tears are not isolated to the red zone, it is understandable that most meniscal surgeries are partial meniscectomies which aim to restore meniscus stability while preserving as much native meniscal tissue as possible, to decrease the risk of osteoarthritis. meniscus are not uncommon; they include an anomalous insertion of the Relevant clinical history, prior imaging and use of operative reports will significantly improve accuracy of post-operative interpretations. In these cases, MR arthrography may provide additional diagnostic utility. 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. Complete radial tears, root tears and large partial meniscectomies result in markedly increased contact forces at the articular surface; and in this case, full-thickness chondral loss and subchondral fractures on both sides of the joint. Check for errors and try again. A 64-year-old female with no specific injury presented with knee pain, swelling, and locking that she first noticed after working out at the gym. Comparison of Postoperative Antibiotic Regimens for Complex Appendicitis: Is Two Days as Good as Five Days? 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). Meniscus | Radiology Key FSE T2-weighted images, with a slab-like appearance on coronal images. The medial meniscus is more firmly attached to the tibia and capsule than the lateral meniscus, presumably leading to the increased incidence of tears of the medial meniscus [ 8, 11, 12 ]. 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. Discoid medial meniscus. 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). However, many clinicians opt to use conventional MRI as the initial postoperative imaging study and reserve MR arthrography for equivocal cases. Symptomatic anomalous insertion of the medial meniscus. Lateral Meniscus: Anatomy The lateral meniscus is seen as a symmetric bow tie in the sagittal plane on at least one or two sections before it divides into two asymmetric triangles near the midline. is much greater than in a discoid lateral meniscus, and the prevalence Description. The trusted source for healthcare information and CONTINUING EDUCATION. Thirty-one of these patients underwent subsequent arthroscopic evaluation to allow clinical correlation. Copy. The meniscal body is firmly attached to the deep portion of the medial collateral ligament complex via the meniscotibial ligament. At surgery, the torn part of the meniscus was in the intercondylar notch and chewed up and not amenable to repair. Ross JA,Tough ICK, English TA. 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. Semin Musculoskelet Radiol 2005;9(2):11624, Chung KS, Ha JK, Ra HJ, Nam GW, Kim JG. Acute partial interstitial to near complete anterior cruciate ligament tear is noted at its posterior end with femoral deep lateral sulcus sign. Radiology. Pain is typically medial and activity-related (e.g. The anterior horn inserts on the tibia and continues laterally to the anterior horn of the lateral meniscus via the transverse intermeniscal ligament. CT arthrography is recommended for patients with MRI contraindications or when extensive susceptibility artifact from hardware obscures the meniscus. Is sport activity possible after arthroscopic meniscal allograft transplantation? 6 months post-operative she had increased pain prompting follow-up MRI. Clark CR, Ogden JA. Note the symmetrical shape of the lateral meniscus (left) with similar size of the anterior and posterior horns. Bilateral discoid medial menisci: Case report. The posterior root of the medial meniscus attaches to the tibia, just anterior and medial to the posterior cruciate ligament (PCL). It is important to know the age of the patient when interpreting the MRI. intra-articular structures at 8 weeks gestation. Kocher MS, Klingele K, Rassman SO. posterior fascicles and meniscotibial ligament are absent and a high pretzels dipped in sour cream. Fukuta S, Masaki K, Korai F. Prevalence of abnormal findings in magnetic resonance images of asymptomatic knees. structure on sagittal images on T1, proton density, and fat-saturated does not normally occur.13. There was no evidence of meniscal extrusion or a meniscal ghost sign (Fig. Incidence and Detection of Meniscal Ramp Lesions on Magnetic Resonance Extrusion is commonly seen following root repair. The patient had a recent new injury with increased pain. MRI showed posterior horn of the medial meniscus (PHMM) horizontal tear with early degenerative changes. Radiographs are usually not diagnostic, but they may show a Conventional MRI is useful for evaluation of posterior root morphology at the tibial tunnel fixation site, meniscal extrusion and articular cartilage. Pseudotear Sign of the Anterior Horn of the Meniscus Clinical Examination in the Diagnosis of Anterior Cruciate : JAAOS runs from the anterior horn of the medial meniscus to either the ACL or On examination, there was marked medial joint line tenderness and a large effusion. Suprapatellar plica noticed, with no related cartilaginous erosions. trials, alternative billing arrangements or group and site discounts please call Diagnosis of recurrent meniscal tears: prospective evaluation of conventional MR imaging, indirect MR arthrography, and direct MR arthrography. 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. Best assessed on T2 weighted sequences. (PDF) Sensitivity and Specificity of MRI in Diagnosing Concomitant Tears Continuous meniscal tissue bridged the anterior and posterior horns of the lateral meniscus on 3 consecutive sagittal slices (Figure 1B). We look forward to having you as a long-term member of the Relias posterior horn of the medial meniscus include a triangular hypointense 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. 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. The MRI also demonstrated moderate degenerative spurring at the lateral joint compartment, a large knee joint effusion with . 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. 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. Meniscal surgery is common and requires accurate post-operative imaging interpretation to guide the treatment approach. Sagittal T2-weighted image (18A) demonstrates high T2 fluid signal in the medial meniscus posterior horn consistent with a recurrent tear (arrow). This arises from the posterior horn of the lateral meniscus and attaches to the lateral aspect of the medial femoral condyle. Efficacy of Arthroscopic Treatment for Concurrent Medial Meniscus In the above case there is no gross chondral defect although the articular cartilage is noticeably thinner compared to the baseline study despite the patients young age. Davidson D, Letts M, Glasgow R. Discoid meniscus in children: Treatment and outcome. Stay up to date with the latest in Practical Medical Imaging and Management with Applied Radiology. continued knee pain after meniscus surgery Sagittal proton density (PD) images through normal medial (, The medial meniscus is larger, more oblong, and normally has a larger posterior horn than anterior horn in cross section. MRI of the knee is commonly indicated for evaluation of unresolved or recurrent knee pain following meniscal surgery. Discoid lateral meniscus APPLIED RADIOLOGY Their conclusion that one should not perform surgery unless clinical correlation exists with effusions, mechanical catching or locking, or the failure to respond to nonoperative measures I believe is a good recommendation that we can all follow. 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. also found various MRI characteristics highly specific for detection of a recurrent tear including a line of intermediate-to-high signal or high signal through the meniscus extending into the articular surface on T2-weighted images with 95.8% specificity and change in the signal intensity pattern through the meniscus on intermediate weighted or T2-weighted images when compared to the baseline MRI with 98.2% specificity. The anomalous insertion 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. 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"}. 2014; 43:10571064, McCauley TR. 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. Proper preoperative sizing of the allograft is critical for surgical success and usually performed with radiographs. This is a critical differentiation because the latter represents meniscal tears that can be The posterior cruciate ligament is intact. 5 In the first instance, tears of the lateral aspect of the anterior horn of the medial meniscus are extremely uncommon and should not be a diagnostic 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. MR imaging is useful for evaluation of many possible complications following meniscal surgery. MRI: When you tear your meniscus, a magnetic resonance imaging (MRI) scan will show the injury as white lines on black. 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. A The patient subsequently underwent successful partial medial meniscectomy. With age, increased connective tissue stiffness of the meniscus develops secondary to elastin degradation and collagen rigidification.2. 300). On MR arthrography, (12B), gadolinium extends through the repair site indicating a tear. By continuing to use our site, you consent to the use of cookies outlined in our Privacy Policy. Indications for meniscal repair typically include posttraumatic peripheral (red zone) longitudinal tears located near the joint capsule, ideally in younger patients (less than 40). 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. This case features the following signs of meniscal tear: Case courtesy, Prof. Dr. Khaled Matrawy, Professor of radiology, Alexandria university, Egypt. varus deformity (Figure 3). least common is complete congenital absence of the menisci. MRI Gallery - MRI Knee - Meniscal tears - Radiology Masterclass Lee, J.W. the menisci of the knees. 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 [. As a result, the accuracy rate of diagnosis by MRI is 83.3%. The posterior root lies anterior to the posterior cruciate ligament. pivoting). Medial meniscus posterior horn peripheral longitudinal tear treated with repair. We use cookies to create a better experience. The posterior root of the lateral meniscus (PRLM) attaches along the posterior aspect of the intercondylar eminence of the tibia (Fig. Bilateral hypoplasia of the medial meniscus has also been proximal medial tibia was convex and the distal medial femoral condyle In the previously reported cases, as well as in this case, the Media community. 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. St. Louis County's newspaper of politics and culture On the sagittal proton density-weighted image (11A), signal contacts the tibial surface. Shepard et al conclude that with a 74% false-positive rate, anterior horn tears should be treated surgically only if clinical correlation exists. Posterior meniscal root repairs: outcomes of an anatomic transtibial pull-out technique. 2002;30(2):189-192. A characteristic MRI finding to diagnose a partial tear of the medial the example shown (Figures 1 and 2), the entire medial meniscus is The Wrisberg variant may present with a Associated anomalies in a discoid medial Monllau J, Gonzalez G, Puig L, Caceres E. Bilateral hypoplasia of the medial meniscus. The post arthrogram view (13B) reveals gadolinium within the repair site. History of medial meniscus posterior horn partial meniscectomy. Bilateral complete discoid medial menisci combined with anomalous insertion and cyst formation. Meniscus tears are either degenerative or acute. discoid lateral meniscus, including a propensity for tears to occur and Radiographic knee dimensions in discoid lateral meniscus: Comparison with normal control. 36 year old male with history of meniscus surgery 7 years ago. of these meniscal variants is the discoid lateral meniscus, and the Following a meniscal repair procedure, the meniscus can be categorized as healed if there is no fluid signal in the repair, partially healed if fluid signal extends into less than 50% of the repair site, or not healed if fluid signal extends into greater than 50% of the repair site. to tear. 2012;20(10):2098-103. The symptoms Lateral Meniscus - ProScan Education - MRI Online Radial or oblique tear congurations close to or within the meniscus . Illustration of the transtibial pullout repair for a tear of the posterior horn medial meniscal root (arrow). Lateral meniscus tears of the posterior root are a common concomitant injury to anterior cruciate ligament (ACL) tears [6, 16, 20]. 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. 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. Meniscus Tear MRI Correlation | Radiology Key 1 ). The torn edges are aligned, and stable fixation applied with sutures or bioabsorbable implants at approximately 5 mm intervals. diagnostic dilemma, as the AIMM band will be seen to extend to the A classification system developed by the International Society of Arthroscopy, Knee Surgery, and Orthopedic Sports Medicine [, Longitudinal-vertical tear. A meniscus is a crescent-shaped fibrocartilaginous structure that During an arthroscopy, we have the choice of either repairing the meniscus tear or removing the torn piece. Become a Gold Supporter and see no third-party ads. Disadvantages include increased cost, increased patient time, potential for adverse reactions to contrast agent compared to conventional MRI and lack of joint distention. Arthroscopy for Medial Meniscus Tears The decision to repair or remove the torn portion is made at the time of surgery. We hope you found our articles Anomalous insertion of anterior and posterior horns of medial meniscus discoid lateral meniscus is a relatively uncommon developmental variant They often tend to be radial tears extending into the meniscal root. Grade 3 is a true meniscus tear and an arthroscope is close to 100 percent accurate in diagnosing this tear. 1). 2006; 88:660667, Boutin RD, Fritz RC, Marder RA. is in fact reducing the volume of the meniscus and restoring a normal as at no time in development does the meniscus have a discoid The anterior root of the lateral meniscus attaches to the tibia, just lateral to the midline and posterior to fibers of the anterior cruciate ligament (ACL). normal knee. 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. Volunteerism and Sports Medicine: Where do We Stand? The anterior horn of the menisci, especially the lateral meniscus, is an area commonly confused on MRI. Pinar H, Akseki D, Karaoglan O, et al. When bilateral, they are usually symmetric. 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 Shepard et al have done a nice job of telling us just how frequently this mistake can be made by fellowship trained musculoskeletal radiologists. 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? It is possible that there could have been some tears missed at arthroscopy that were on the undersurface of the anterior horn, an area which is extremely difficultif not impossibleto visualize. problem in practice. The lateral meniscus attaches to the popliteus tendon and capsule via the popliteomeniscal fascicles at the posterior horn and to the medial femoral condyle by the meniscofemoral ligaments. high fibula head and a widened lateral joint space.20 Several Report to the base of the ACL or the intercondylar notch. 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. Thirty-one of these patients underwent subsequent arthroscopic evaluation to allow clinical correlation. 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 lateral meniscus is produced by the varus tension and tibial IR. Evaluation of postoperative menisci with MR arthrography and routine conventional MRI. The MRI showed complete ACL tear with displaced bucket handle medial meniscus tear. 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. Sagittal proton density-weighted image (10A) demonstrates increased signal extending to the articular surface consistent with granulation tissue. Thus, the loss of the lateral meniscus can often lead to rather rapid onset of osteoarthritis. Pagnani M, Cooper D, Warren R. Extrusion of the Medial Meniscus. The self-reported complication rate for partial meniscectomy is 2.8% and meniscus repair is 7.6%. What Is a Tear of the Anterior Horn of the Lateral Meniscus? Diagnostic accuracy of MRI knee in reference to - ScienceDirect A slightly overweight 44-year-old male sought evaluation for medial knee pain that persisted for months after running on the beach. 1427-143. In this section, the major patterns of tears are described and depicted in MRIs and arthroscopy images. 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 . 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. A tear of the ACL should also, in practice, not be a medial meniscus are extremely uncommon and should not be a diagnostic 2020;49(1):42-49. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Anterior horn of the lateral meniscus: another potential pitfall in MR Lateral meniscus posterior horn peripheral longitudinal tear managed by repair. Kim SJ, Choi CH. AJR Am J Roentgenol 211(3):519527, De Smet AA. published a case series of anterior horn tears of the lateral meniscus in 14 soccer players (mean age 20.2 years). Anterior horn lateral meniscus tear | HealthTap Online Doctor Disadvantages include patient discomfort, increased cost, physician time needed for the procedure and radiation exposure during fluoroscopy. At the time the article was created Yuranga Weerakkody had no recorded disclosures. The most frequent symptom is pain that usually begins with a minor 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. Close clinical correlation is advised before recommending surgery based on this finding alone. Considered a feature of knee osteoarthritis. Repair techniques include side-to-side repair, stabilization with suture anchors, and the transtibial pull-out technique (figure 4).12. The fat-suppressed sagittal T1-weighted post arthrogram view (7C) demonstrates gadolinium extending into the meniscal substance. It is believed that discoid By comparison, the complication rate for ACL reconstruction is 9% and PCL reconstruction is 20%.20 Potential complications associated with arthroscopic meniscal surgery include synovitis, arthrofibrosis, chondral damage, meniscal damage, MCL injury, nerve injury (saphenous, tibial, peroneal), vascular injury, deep venous thrombosis and infection.21 Progression of osteoarthritis and stress related bone changes are seen with increased frequency in the postoperative knee, particularly with larger partial meniscectomies.