Source: Shepard MF, et al. Radiographs are usually not diagnostic, but they may show a This patient had relief after the initial repair surgery, then had a second injury with recurrent symptoms, which is why the surgeon felt this was a recurrent tear. Renew or update your current subscription to Applied Radiology. in 19916. Shepard et al have done a nice job of telling us just how frequently this mistake can be made by fellowship trained musculoskeletal radiologists. Meniscal root tear. In the previously reported cases, as well as in this case, the 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 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 ]. 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. of the distal femur and proximal tibia, and in the case report of 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. 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. We look forward to having you as a long-term member of the Relias At 1 year, 5 of 6 were completely asymptomatic with the remaining patient minimally painful with no suggestion of meniscal symptoms. Become a Gold Supporter and see no third-party ads. This is a well-done study with clinical correlation and adequate follow-up. Am J Sports Med. MRI showed posterior horn of the medial meniscus (PHMM) horizontal tear with early degenerative changes. Exam showed a mild effusion and medial joint line tenderness. tear. 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. Meniscal surgery is common and requires accurate post-operative imaging interpretation to guide the treatment approach. Proper preoperative sizing of the allograft is critical for surgical success and usually performed with radiographs. Coronal extrusion of the lateral meniscus does not increase after Pseudotear Sign of the Anterior Horn of the Meniscus Tears Thirty-one of these patients underwent subsequent arthroscopic evaluation to allow clinical correlation. The lateral meniscus is more circular, and its anterior and posterior horns are nearly equivalent in size in cross section. | 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. variants of the meniscus are relatively uncommon and are frequently Irrespective of the repair approach or repair devices used, diagnostic criteria for a recurrent tear remains the same fluid signal or contrast extending into the meniscal substance. 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. Best assessed on T2 weighted sequences. Diagnosis - clinical presentation with exclusion of advanced knee osteoarthritis. In these cases, MR arthrography may provide additional diagnostic utility. At second look arthroscopy, the posterior horn tear was healed and the anterior horn tear was found to be unstable and treated by partial meniscectomy. The MRI showed complete ACL tear with displaced bucket handle medial meniscus tear. high fibula head and a widened lateral joint space.20 Several PDF ssslideshare.com The anterior and posterior meniscofemoral ligaments (Humphrey and Wrisberg respectively) are commonly present with one or both found in 93-100% of patients.9 The lateral meniscus is more loosely attached than the medial and can translate approximately 11mm with normal knee motion.10. posterior fascicles and meniscotibial ligament are absent and a high 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. Anterior Cruciate Ligament and Meniscal Tears: A Multi-modality Review Each meniscus has three main parts, the back (posterior horn), middle (body), and front (anterior horn). Biologic augmentation with application of exogenous fibrin clot or growth factors may be combined with the repair to promote healing. 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. Menisci are present in the knees and the The lateral meniscus is produced by the varus tension and tibial IR. Case study, Radiopaedia.org (Accessed on 04 Mar 2023) https://doi.org/10.53347/rID-75066. Increased signal intensity at the anterior horn of the lateral meniscus was seen on the images of seven of the 11 MR studies of the volunteers. Conventional MRI is useful for evaluation of posterior root morphology at the tibial tunnel fixation site, meniscal extrusion and articular cartilage. 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. Is sport activity possible after arthroscopic meniscal allograft transplantation? Lateral meniscus extrusion was present in six (23%) of 26 LMRTs and five (2.2%) of 231 patients with normal meniscus roots ( P < .001). Discoid medial meniscus. 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. Posterior meniscal root repairs: outcomes of an anatomic transtibial pull-out technique. Which meniscus is more likely to tear? The patient underwent meniscal repair but had recurrent pain prompting repeat MRI 8 months post-operative. of the Wrisberg ligament in patients with a complete lateral discoid At least one meniscofemoral ligament is present in 7093 % Of knees Close clinical correlation is advised before recommending surgery based on this finding alone. The MFL was not observed in five (19%) of 26 studies of an LMRT. Meniscal tears were found on MRI or arthroscopy in all 28 patients with a lateral cyst overlying the body or posterior horn of the lateral meniscus, whereas a tear was found on MRI or arthroscopy in only 14 (64%) of 22 patients with cysts adjacent to or extending to the lateral meniscus anterior horn (p = 0.006). Factors affecting meniscal extrusion: correlation with MRI, clinical Description. The Knee Resource | Degenerative Meniscus Tear Cho JM, Suh JS, Na JB, et al. 3: The Wrisberg variant, where the meniscus may have a normal 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. The Postoperative Meniscus - Radsource reported.4. Anterior horn lateral meniscus tear A female asked: Mri: "macerated anterior horn lateral meniscus with inferiorly surfacing tear. posterior horn of the medial meniscus include a triangular hypointense 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. Meniscal root tears are a form of radial tear that involves the central attachment of the meniscus (12a). An intact meniscal repair was confirmed at second look arthroscopy. The posterior root of the medial meniscus attaches to the tibia, just anterior and medial to the posterior cruciate ligament (PCL). MR criteria for discoid lateral menisci are used for discoid medial When bilateral, they are usually symmetric. structure on sagittal images on T1, proton density, and fat-saturated > 20% ratio of meniscus to tibia on the coronal image; Minimum diameter 14-15 mm on a midcoronal image; 75% Normal are reported cases of complete absence of the medial meniscus as 36 year old male with history of meniscus surgery 7 years ago. 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. For root tears in general, sagittal imaging may demonstrate a meniscal ghost sign. The most common History of medial meniscus posterior horn partial meniscectomy. Repair techniques include inside-out, outside-in or all-inside approaches. Posterior Horn Lateral Meniscus Tear | Knee Specialist | Minnesota CT arthrography is recommended for patients with MRI contraindications or when extensive susceptibility artifact from hardware obscures the meniscus. Definite surfacing signal or distortion on only one image represents a possible tear. 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). Longitudinal lateral meniscus tear status post repair (arrow). Meniscus tears are either degenerative or acute. Of the 54 participants, 5 had PHLM tears and 49 were normal. They are most frequently seen at the posterior horn of the medial meniscus. The remaining 42 cases were located in the red zone (19 cases) or the red-white zone. The anterior and posterior sutures are shuttled down the tibial tunnel (arrowhead). The most widely used diagnostic modalities to assess the ligament injuries are arthroscopy and Magnetic Resonance Imaging (MRI). On MRI, they resemble radial tears, with a linear cleft of abnormal signal seen at the free edge. 2008;191(1):81-5. Fellowship-trained musculoskeletal radiologists read 99% of the MRIs. Meniscal tears are common and often associated with knee pain. The patient subsequently underwent successful partial medial meniscectomy. Repair techniques include side-to-side repair, stabilization with suture anchors, and the transtibial pull-out technique (figure 4).12. However, recognizing these variants is important, as they can 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. Unable to process the form. (as previously described), meniscal cyst,26 discoid lateral meniscus in the same knee (Figure 9),25 and pathologic medial patella plica.27. immediatly lateral to the anterior horn of lateral meniscus and posterior to the tubercle of anteriro horn of medial meniscus . There is no universally accepted system for classifying meniscal tear patterns. 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 Incidence and Detection of Meniscal Ramp Lesions on Magnetic Resonance
