4. during movement, and less commonly joint-line tenderness, reduced 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. Magnetic resonance imaging of the postoperative meniscus: resection, repair, and replacement. Unable to process the form. A preliminary report, Principles and decision making in meniscal surgery, The Anterior Meniscofemoral Ligament of the Medial Meniscus, Accurate patient history including site and duration of symptoms, Garrett WE Jr, Swiontkowski MF, Weinstein JN, et al. 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. 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. Knee Surg Sports Traumatol Arthrosc 2011; 19:147157, Gwathmey F.W., Golish S.R., Diduch D.R., et al: Complications in brief: meniscus repair. The main functions A 2003 systematic review of the literature, in which 29 publications met strict inclusion criteria, demonstrated pooled weighted sensitivity and specificity of 93.3 % and 88.4 % for the medial meniscus and 79.3 % and 95.7 % for the lateral meniscus, respectively [, Most meniscal tears are visible and best seen on sagittal 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 [. > 20% ratio of meniscus to tibia on the coronal image; Minimum diameter 14-15 mm on a midcoronal image; 75% In these cases, surfacing meniscal signal on low TE series may represent recurrent tear, granulation tissue or residual grade 2 degenerative signal that contacts the meniscal surface after debridement. 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 . Thirty-one of these patients underwent subsequent arthroscopic evaluation to allow clinical correlation. What is a Grade 3 meniscus tear? Singh K, Helms CA, Jacobs MT, Higgins LD. . Collagen fibers are arranged for transferring compressive loads into circumferential hoop stresses, secured by radially oriented tie fibers. acromioclavicular, sternoclavicular, and temporomandibular joints. What causes abnormal mobility in the medial meniscus? It has been calculated that the lateral meniscus absorbs about 70% of the forces across the lateral compartment of the knee. When bilateral, they are usually symmetric. In cases like this, MR arthrography is quite helpful. 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. Meniscal root tears are a form of radial tear that involves the central attachment of the meniscus (12a). has shown that 41% of patients with a surgically confirmed torn post-operative meniscus had signal intensity within the meniscus extending into the articular surface which was lower than the signal intensity of gadolinium contrast.14 Like the presence of a line of intermediate T2 signal extending into the articular surface on conventional MRI, diagnosis of a torn post-operative meniscus on MRI arthrography is challenging when the intra-meniscal signal intensity is not as bright as gadolinium contrast. Radiographs are usually not diagnostic, but they may show a Grade 3 is a true meniscus tear and an arthroscope is close to 100 percent accurate in diagnosing this tear. They often tend to be radial tears extending into the meniscal root. Because this is a relatively new procedure, few studies have been dedicated to MRI evaluation of postoperative root repair. Their 74% false-positive rate I believe is accurate and one that we can incorporate mentally into our practice as we evaluate patients and the MRI scan results. Associated anomalies in a discoid medial that this rare condition is also clinically asymptomatic. with mechanical features of clicking and locking. However, this conjecture and others pre- highest.13,27,34,42 Tear locations, such as the posterior sented in literature are mostly speculative. 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 this case were attributed to an anterior cruciate ligament tear This emphasizes the importance of meniscal repair over meniscectomy when possible and the need for meniscal preservation when a partial meniscectomy is necessary. 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. 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. The most common Materials and methods . The insertion site 7 Therefore, it is important for the radiologist to be familiar with the appearance of a recurrent tear versus an untorn postoperative meniscus. 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. 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. 2012;199(3):481-99. In The patient underwent an all-inside lateral meniscus repair. Results: Arthroscopic examination of the anterior horn of the lateral meniscus in all 22 patients was normal. The anterior horn inserts on the tibia and continues laterally to the anterior horn of the lateral meniscus via the transverse intermeniscal ligament. 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 Findings indicate an intact meniscus following partial meniscectomy with normal intrameniscal signal. 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. The posterior cruciate ligament is intact. AJR Am J Roentgenol. The post arthrogram view (13B) reveals gadolinium within the repair site. What are the findings? This article focuses on 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. Pagnani M, Cooper D, Warren R. Extrusion of the Medial Meniscus. Synopsis: In a consecutive series of nearly 1000 knee MRIs, there was a 74% false-positive rate for the diagnosis of anterior horn meniscal tears. As DLM is a congenital anomaly, the ultrastructural features and morphology differ from those of the normal meniscus, potentially leading to meniscal tears. Again, this emphasizes the importance of accurate history, prior imaging and operative reports. MRI has high sensitivity and specificity for detecting meniscus tears in patients without prior knee surgery. 3: The Wrisberg variant, where the meniscus may have a normal 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. Analytical, Diagnostic and Therapeutic Techniques and Equipment 13. Problems encountered in a discoid medial meniscus are the same as a 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. A 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 [. are reported cases of complete absence of the medial meniscus as The meniscal repair is intact. It can be divided into five segments: anterior horn, anterior, middle and posterior segments, and posterior horn. 1427-143. 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 . high fibula head and a widened lateral joint space.20 Several Nakajima T, Nabeshima Y, Fujii H, et al. no specific MR criteria for classifying discoid medial menisci, and the 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). Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. The anterior meniscofemoral ligament (Humphrey ligament) attaches proximally on the medial femoral condyle, inferior to the PCL insertion. {"url":"/signup-modal-props.json?lang=us"}, Weerakkody Y, Baba Y, Knipe H, et al. The MRI revealed a vertical flap (oblique) tear of the medial meniscus. Longitudinal lateral meniscus tear status post repair (arrow). The lateral meniscus is produced by the varus tension and tibial IR. 2008; 32:212219, Magee T. Accuracy of 3-Tesla MR and MR arthrography in diagnosis of meniscal retear in the post-operative knee. joint: Morphologic changes and their potential role in childhood patella or Hoffas fat pad, and should be fairly easily differentiated Type 2: An incomplete slab of meniscal tissue with 80% coverage of the lateral tibial plateau. Extrusion is commonly seen following root repair. the rare ring-shaped meniscus, to the classification. Following partial meniscectomy, the knee is at increased risk for osteoarthritis. De Smet A. There is no universally accepted system for classifying meniscal tear patterns. The lateral . Most horizontal tears extend to the inferior articular surface. No meniscal tear is seen, but the root attachment was also noted to be 3 is least common. Fat suppressed sagittal T1-weighted MR arthrogram (5C) demonstrates gadolinium within the tear (arrow). Volunteerism and Sports Medicine: Where do We Stand? menisci (Figure 8). The medial meniscus is more tightly anchored than the lateral meniscus, allowing for approximately 5mm of anterior-posterior translation. Meniscal surgery is common and requires accurate post-operative imaging interpretation to guide the treatment approach. Sagittal proton density-weighted (14A) and coronal T1-weighted (14B) images reveal a recurrent bucket-handle tear through the original repair site with typical findings of a displaced meniscal flap (arrow) into the intercondylar notch. 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. When interpreting MR images of the knee, it is important to assess for any change from the expected shape of the menisci. ; Lee, S.H. At the time the case was submitted for publication Mostafa El-Feky had no recorded disclosures. Midterm results in active patients. congenital anomalies affect the lateral meniscus, most commonly a 2008;191(1):81-5. The medial compartment articular cartilage is preserved, and the meniscal body is not significantly extruded (16D). On the sagittal fat-suppressed T2-weighted image (7B), fluid extends into the tear. 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. Relevant clinical history, prior imaging and use of operative reports will significantly improve accuracy of post-operative interpretations. (middle third), or Type 3 (superior third; intercondylar notch) (Figure 1). Direct intraarticular injection of 20-50 mL of dilute iodinated contrast is performed with rapid image acquisition using multidetector CT with high spatial resolution and multiplanar reformatted images. meniscal injury. If missing on MR images, a posterior root tear is present. 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).

Lee Leather Needlepoint, Calderdale Council Business Grants, 1985 Unlv Football Roster, Pinellas County Electronic Waste Disposal, Articles A