7
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Ressonância magnética na avaliação das variações anatômicas meniscais e da anatomia ligamentar perimeniscal: potenciais causas de erro de interpretação Translated title: Magnetic resonance imaging in the assessment of meniscal anatomic variants and of the perimeniscal ligamentous anatomy: potential interpretation pitfalls

      review-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          O conhecimento adequado das variações anatômicas meniscais e das estruturas perimeniscais é essencial para uma avaliação adequada dos exames de ressonância magnética do joelho, tanto no diagnóstico das lesões meniscais quanto para se evitar uma série de possíveis erros diagnósticos. Este artigo revê variações anatômicas que alteram o tamanho, a forma e a estabilidade meniscais e que incluem os vários tipos de menisco discoide, outras variações morfológicas meniscais menos frequentes e o ossículo meniscal. Também é revisada a anatomia de estruturas perimeniscais, principalmente ligamentares, que incluem os ligamentos meniscocapsulares, intermeniscais, meniscofemorais e extensões meniscoligamentares.

          Translated abstract

          The knowledge of meniscal anatomic variants and of the normal perimeniscal structures is essential to understand magnetic resonance imaging studies of the knee, both for the diagnosis of meniscal lesions and to avoid potential interpretation pitfalls. The present article reviews anatomic variants that change the size, shape and stability of the menisci, including the different types of discoid menisci, other less frequent meniscal malformations and the meniscal ossicle. Additionally, the anatomy of perimeniscal structures, particularly those including the meniscocapsular, intermeniscal, meniscofemoral ligaments and other menisco-ligamentous structures is reviewed.

          Related collections

          Most cited references40

          • Record: found
          • Abstract: found
          • Article: not found

          Arthroscopic treatment of symptomatic discoid meniscus in children: classification, technique, and results.

          The purpose of this study was to review the operative results of children and young adults treated arthroscopically for symptomatic discoid lateral menisci. The medical records and radiographic studies of 27 consecutive patients (30 knees) who underwent arthroscopic treatment for symptomatic discoid meniscus between 1998 and 2002 were reviewed. The mean patient age was 10.1 years (range, 3 to 20 years), with 19 female and 8 male patients. The mean duration of symptoms before surgery was 13.9 months, with 28 knees (93%) having pain and 20 knees (67%) having mechanical symptoms. All patients were treated arthroscopically. Arthroscopic saucerization was successful in 28 of 30 knees. In 2 cases with large complex tears meniscal salvage was not possible and a complete arthroscopic meniscectomy was performed. Operative classification of the menisci revealed 22 complete (4 Wrisberg type) and 8 incomplete discoid menisci, with meniscal tears being present in 23 of 30 (77%). Meniscal instability was noted in 77% of knees (23 of 30), with anterior horn instability in 53% (n = 16), posterior instability in 16% (n = 5), and combined anterior and posterior instability in 6% (n = 2). All cases of anterior horn instability were treated with an outside-in arthroscopic repair technique, whereas all cases of posterior horn instability were treated with meniscal repair via an inside-out arthroscopic technique. Twenty-one patients (23 knees) had full follow-up of greater than 1 year. For these 21 patients, the mean length of follow-up was 37.4 months (range, 12 to 77 months), and at final follow-up, all patients exhibited full knee flexion beyond 135 degrees. Three patients reported residual knee pain, and four reported intermittent mechanical symptoms. At final follow-up, 2 patients felt that their activity level remained partially limited. Our results show the short-term efficacy of arthroscopic saucerization and repair to the capsule in selected cases of symptomatic discoid menisci. On the basis of this experience and other recent reports documenting a high rate of anterior horn instability, an arthroscopic classification system for discoid lateral menisci is proposed. Menisci are classified as complete or incomplete discoid and are then subclassified based on the presence of instability as a result of deficient capsular attachment and, finally, based on the location of the absent capsular attachment. Level IV, therapeutic case series.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Discoid menisci of the knee: MR imaging appearance.

            Discoid menisci of the knee are not uncommon, and the criteria for arthrographic diagnosis and the clinical symptoms are well known. Although enlarged menisci have been recognized at magnetic resonance (MR) imaging, there are no criteria for the MR imaging diagnosis. The authors describe 29 discoid menisci imaged by means of MR. A discoid meniscus was said to be present if three or more 5-mm-thick contiguous sagittal images demonstrated continuity of the meniscus between the anterior and posterior horns. High-resolution coronal images allowed more graphic depiction of the abnormally wide meniscus. In approximately one-third of the cases in which coronal images were obtained, the measurable height difference between the discoid and the opposite meniscus was greater than or equal to 2 mm. Arthroscopic correlation (obtained in 10 cases) revealed that six cases of discoid meniscus were diagnosed correctly with MR imaging, although one meniscus was considered discoid at MR imaging but was not considered discoid at arthroscopy. Of three discoid menisci seen to be torn at arthroscopy, two were seen to be torn at MR imaging.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Discoid lateral meniscus and the frequency of meniscal tears.

              To use MRI to determine the incidence of discoid lateral menisci in a large study population, and to compare those patients with those without a discoid meniscus in order to assess the impact of a discoid lateral meniscus on the frequency of meniscal tears. Results of 1,250 knee MRI studies were retrospectively reviewed. Using the criterion of three or more meniscal body segments on sequential sagittal images, 56 patients were found to have a discoid lateral meniscus. After exclusion of patients with prior knee surgery, 49 patients with a discoid lateral meniscus were compared with 1,146 patients without a discoid meniscus. Patients were categorized as having tears of the medial meniscus, lateral meniscus, or both menisci. In our study population, there was a 4.5% incidence of discoid lateral meniscus. Seventy-one percent of patients with a discoid lateral meniscus had one or more meniscal tears, compared with 54% of the comparison group (P=0.01). The frequency of solitary lateral meniscal tears in the discoid group was also higher than in the comparison group: 20%.versus 11% (P=0.03). The frequency of solitary medial meniscal tears and concomitant tears of both menisci were not significantly different between the two groups. The discoid lateral meniscus is an uncommon variant, but not as rare as once believed. Compared with the normal semilunar meniscus, the discoid lateral meniscus has a higher frequency of meniscal tears, and solitary tears of the lateral meniscus are more common in the discoid variant. The frequency of medial meniscal tears is not altered by the presence of a discoid lateral meniscus.
                Bookmark

                Author and article information

                Journal
                rb
                Radiologia Brasileira
                Radiol Bras
                Publicação do Colégio Brasileiro de Radiologia e Diagnóstico por Imagem (São Paulo, SP, Brazil )
                1678-7099
                April 2011
                : 44
                : 2
                : 117-122
                Affiliations
                [03] Ribeirão Preto SP orgnameUniversidade de São Paulo orgdiv1Faculdade de Medicina de Ribeirão Preto Brasil
                [01] orgnameCentral de Diagnóstico Ribeirão Preto
                [02] Ribeirão Preto SP orgnameUniversidade de São Paulo orgdiv1Faculdade de Medicina de Ribeirão Preto orgdiv2Hospital das Clínicas Brasil
                Article
                S0100-39842011000200012 S0100-3984(11)04400212
                bc8a73ae-b124-4031-99ac-cc514addaa10

                This work is licensed under a Creative Commons Attribution 4.0 International License.

                History
                : 28 May 2010
                : 19 October 2010
                Page count
                Figures: 0, Tables: 0, Equations: 0, References: 40, Pages: 6
                Categories
                Artigo de Revisão

                Magnetic resonance imaging,Anatomic variants,Discoid meniscus,Menisco discoide,Knee,Imagem por ressonância magnética,Variações anatômicas,Joelho

                Comments

                Comment on this article