anterior horn lateral meniscus tear: mri

show cupping of the medial tibial plateau, proximal medial tibial physis This emphasizes the importance of meniscal repair over meniscectomy when possible and the need for meniscal preservation when a partial meniscectomy is necessary. Each meniscus attaches to the tibia bone in the back and front via the "meniscal roots." The primary role of the meniscus is to serve as a shock-absorber and protect the underlying articular cartilage and bone. 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. Arthroscopy revealed a horizontal tear of PHMM, and a partial medial meniscectomy was performed. These include looking for a 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 Normal shape and signal of the horns of the medial meniscus, with no evidence of tears or degenerations seen. There are 3 main types, according to the Watanabe classification:18. Meniscus tears, indicated by MRI, are classified in three grades. of the meniscus. attachment of the posterior horn is the Wrisberg meniscofemoral 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. 4. Absence of the meniscus results in a 200 to 300% increase in contact stresses on the articular surfaces.8The meniscus has a heterogeneous cellular composition with regional and zonal variation, with high proteoglycan content at the thin free edge where compressive forces predominate and low proteoglycan content at the thicker peripheral region where circumferential tensile loads predominate. acromioclavicular, sternoclavicular, and temporomandibular joints. 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 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. They are most frequently seen at the posterior horn of the medial meniscus. On this page: Article: Epidemiology Pathology Radiographic features History and etymology Repair techniques include inside-out, outside-in or all-inside approaches. 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. 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. A tear of the meniscal root means the tear is near where it attaches to the bone, usually far in the back. The lateral . 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 . 70 year-old female with history of medial meniscus posterior horn radial tear. Of these patients treated nonoperatively, 6 had a diagnosis of an isolated anterior horn tear on MRI. 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. Anomalous When interpreting MR images of the knee, it is important to assess for any change from the expected shape of the menisci. Illustration of the medial and lateral menisci. 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. [emailprotected]. least common is complete congenital absence of the menisci. Close clinical correlation is advised before recommending surgery based on this finding alone. Kim SJ, Moon SH, Shin SJ. Tear between 1-4 cm vertical tear red-red meniscal root <40 yo Maybe concominant ACL surgery . Radiology. The lateral meniscus is more circular, and its anterior and posterior horns are nearly equivalent in size in cross section. Dr. Diduch, Associate Professor, Department of Orthopaedic Surgery, University of Virginia School of Medicine, Charlottesville, VA, is Editor of Sports Medicine Reports. The lateral meniscus is one of two fibrocartilaginous menisci of the knee. 22 year-old male with a history of ACL and MCL reconstruction and medial meniscus posterior root repair. It has been calculated that the lateral meniscus absorbs about 70% of the forces across the lateral compartment of the knee. 2002;30(2):189-192. 2. Horizontal (degenerative) tears run relatively parallel the tibial plateau. is affected. After preparing the recipient knee by creating a matching keyhole trough in the tibia, the surgeon slides the allograft bone plug into its matching tibial slot and sutures the periphery of the allograft meniscus to the capsule. to the base of the ACL or the intercondylar notch. 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. Development of the menisci of the human knee MRI appearance of Wrisberg variant of discoid lateral meniscus. As DLM is a congenital anomaly, the ultrastructural features and morphology differ from those of the normal meniscus, potentially leading to meniscal tears. The most frequent symptom is pain that usually begins with a minor Exam showed a mild effusion and medial joint line tenderness. Resnick D, Goergen TG, Kaye JJ, et al. They were first described by M J Pagnaniet al. 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 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. Radiology. Fat suppressed sagittal T1-weighted MR arthrogram (5C) demonstrates gadolinium within the tear (arrow). 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. The symptoms According to one source, they are thought to account for ~10% of all arthroscopic meniscectomies 5. 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. A displaced longitudinal tear is a "bucket handle" tear. 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. Collagen fibers are arranged for transferring compressive loads into circumferential hoop stresses, secured by radially oriented tie fibers. 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. Magnetic resonance imaging (MRI) revealed an elongated free edge of the diffusely enlarged lateral meniscus extending toward the intercondylar region on coronal T1-weighted images (Figure 1A). Damaged meniscal tissue is removed with arthroscopic instruments including scissors, baskets and mechanical shavers until a solid tissue rim is reached with the meniscal remnant contoured, preserving of as much meniscal tissue as possible. A 510, 210-pound 16-year-old male injured his left knee while kicking a football. Thirty-one of these patients underwent subsequent arthroscopic evaluation to allow clinical correlation. Figure 8: Medial oblique menisco-meniscal . This mesenchymal He presented after a few months with symptoms of instability. These features constitute O'Donoghue unhappy triad. is in fact reducing the volume of the meniscus and restoring a normal When the cruciate Anterior tibial marrow edema and organized trabecular fracture measuring 16 mm AP, 18 mm transverse. Long-term outcome after arthroscopic meniscal repair versus arthroscopic partial meniscectomy for traumatic meniscal tears. They may not even be apparent with an arthroscopic examination. 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. Shepard et al conclude that with a 74% false-positive rate, anterior horn tears should be treated surgically only if clinical correlation exists. 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. 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. Extension to the anterior cortex of . Medial meniscus posterior horn peripheral longitudinal tear (arrow) seen on the sagittal proton density-weighted image (15A) and managed by repair. 300). of the distal femur and proximal tibia, and in the case report of Bilateral complete discoid medial menisci combined with anomalous insertion and cyst formation. Connolly B, Babyn PS, Wright JG, Thorner PS. congenital anomalies affect the lateral meniscus, most commonly a Radiographs may Symptomatic anomalous insertion of the medial meniscus. Mechanical rasping or trephination of the torn meniscus ends and parameniscal synovium is used to promote bleeding and vascular healing. Meniscal root tears are a form of radial tear that involves the central attachment of the meniscus (12a). If a meniscus tear shows up on a MRI, it is considered a Grade 3. The posterior root lies anterior to the posterior cruciate ligament. Tears can be characterized by length, depth, shape, gap, displacement, stability, dysplasia (discoid) meniscus is partial meniscal excision, leaving a 6- to 7-mm peripheral discoid lateral meniscus, including a propensity for tears to occur and For partial meniscectomies involving 25% or more, conventional MRI has lower accuracy. Discoid lateral meniscus. At least one meniscofemoral ligament is present in 7093 % Of knees Lee, J.W. pivoting). They often tend to be radial tears extending into the meniscal root. . 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. Radial or oblique tear congurations close to or within the meniscus . 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. Disadvantages include patient discomfort, increased cost, physician time needed for the procedure and radiation exposure during fluoroscopy. The patient underwent an all-inside lateral meniscus repair. Both the healed peripheral tear and the new central tear were proved at second look arthroscopy. The anomalous insertion In some patients, hyperintense signal may persist at the repair site on conventional MRI for several years and is thought to represent granulation tissue. Recent evidence suggests that decreased extrusion may correlate to better clinical outcomes.18. 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. Figure 7: Meniscofemoral ligament. 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. of the AIMM into the ACL is classified as Type 1 (inferior third), Type 2 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 [. Acute partial interstitial to near complete anterior cruciate ligament tear is noted at its posterior end with femoral deep lateral sulcus sign. 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. In these cases, MR arthrography may provide additional diagnostic utility. 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. in 19916. small meniscus is also seen in the wrist joint. 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. A detached posterior root is functionally equivalent to a total meniscectomy with loss of its ability to withstand hoop stress. Normal Anterior horn of the lateral meniscus: another potential pitfall in MR imaging of the knee. 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 Lateral meniscal variant with absence of the posterior coronary ligament. Magn Reson Imaging Clin N Am 2014;22(4): 517555, White LM, Schweitzer ME, Weishaupt D, Kramer J, Davis A, Marks PH. that this rare condition is also clinically asymptomatic. Radial Tear of the Medial Meniscal Root: Reliability and Accuracy of MRI for Diagnosis. Kim SJ, Choi CH. Samoto N, Kozuma M, Tokuhisa T, Kobayashi K. Diagnosis of discoid lateral meniscus of the knee on MR imaging. 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. 9 The lateral meniscus is more loosely attached than the medial and can translate approximately 11mm with normal knee motion. Surgery is useful if they are unstable and flipping in and out of the joint causing pain. 2008; 32:212219, Magee T. Accuracy of 3-Tesla MR and MR arthrography in diagnosis of meniscal retear in the post-operative knee. 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. Illustration of the transtibial pullout repair for a tear of the posterior horn medial meniscal root (arrow). For information on new subscriptions, product . Check for errors and try again. This arises from the posterior horn of the lateral meniscus and attaches to the lateral aspect of the medial femoral condyle. On sagittal proton-density and T2-weighted images, this lesion was demonstrated by sensitive but nonspecific signs, such as the flipped meniscus . Both horns of the medial meniscus are triangular with sharp points. The condition is typically asymptomatic and, therefore, is infrequently diagnosed.14 The posterior horn is always larger than the anterior horn. The most common The shape of the meniscus is formed at the eighth week of The patient subsequently underwent successful partial medial meniscectomy. A recurrent tear was proved at second look arthroscopy. No gadolinium extension into the meniscus on fat-suppressed sagittal T1-weighted (9B) post arthrogram view. 3. Clinical imaging. Imaging characteristics of the The remaining 42 cases were located in the red zone (19 cases) or the red-white zone. in this case were attributed to an anterior cruciate ligament tear Discoid lateral meniscus was originally believed to result from an Dr. Michael Gabor answered Diagnostic Radiology 35 years experience No,: It doesn't sound like a bucket handle tear Discoid lateral meniscus in children. This is a well-done study with clinical correlation and adequate follow-up. Cho JM, Suh JS, Na JB, et al. 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.