Association of parameniscal cysts with underlying meniscal tears as identified on MRI and arthroscopy.
ABSTRACT Although patients with parameniscal cysts usually have underlying meniscal tears, we noted that this association was less common with anterior lateral cysts. We wished to determine whether the frequency of a meniscal tear underlying a parameniscal cyst varied with cyst location.
We reviewed a database of 7,771 knee MR examinations and identified 134 patients with an MR diagnosis of 138 parameniscal cysts and correlative arthroscopy in 78 patients. We reviewed their medical records and MR studies to determine the location of the cysts and presence of an underlying meniscal tear as determined by MRI or arthroscopy.
There were 50 lateral and 88 medial parameniscal cysts. Medial meniscal tears were found underlying a cyst in 96% of arthroscopy patients and 86% of patients who had only MR examinations without a location difference in tears (p = 0.68). 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). Anterior lateral cysts extended medially either into the root or into Hoffa fat-pad, but the type of extension did not correlate with the presence of an underlying meniscal tear.
In contrast to medial parameniscal cysts or cysts at other locations adjacent to the lateral meniscus, anteriorly located lateral parameniscal cysts are less likely to have underlying meniscal tears.
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ABSTRACT: The patient was a 21-year-old man who was referred to a physical therapist for a chief complaint of progressively worsening left lateral knee pain that limited his ability to run and perform his military duties. Given the presence of a palpable painful mass at the lateral aspect of the knee and concern for a lateral meniscus tear, magnetic resonance imaging was ordered by the physical therapist, which revealed a large multiloculated lateral parameniscal cyst. J Orthop Sports Phys Ther 2014;44(8):633. doi:10.2519/jospt.2014.0409.Journal of Orthopaedic and Sports Physical Therapy 08/2014; 44(8):633. · 2.38 Impact Factor
- Reumatologia clinica. 08/2014;
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ABSTRACT: Magnetic resonance (MR) imaging is currently the modality of choice for detecting meniscal injuries and planning subsequent treatment. A thorough understanding of the imaging protocols, normal meniscal anatomy, surrounding anatomic structures, and anatomic variants and pitfalls is critical to ensure diagnostic accuracy and prevent unnecessary surgery. High-spatial-resolution imaging of the meniscus can be performed using fast spin-echo and three-dimensional MR imaging sequences. Normal anatomic structures that can mimic a tear include the meniscal ligament, meniscofemoral ligaments, popliteomeniscal fascicles, and meniscomeniscal ligament. Anatomic variants and pitfalls that can mimic a tear include discoid meniscus, meniscal flounce, a meniscal ossicle, and chondrocalcinosis. When a meniscal tear is identified, accurate description and classification of the tear pattern can guide the referring clinician in patient education and surgical planning. For example, longitudinal tears are often amenable to repair, whereas horizontal and radial tears may require partial meniscectomy. Tear patterns include horizontal, longitudinal, radial, root, complex, displaced, and bucket-handle tears. Occasionally, meniscal tears can be difficult to detect at imaging; however, secondary indirect signs, such as a parameniscal cyst, meniscal extrusion, or linear subchondral bone marrow edema, should increase the radiologist's suspicion for an underlying tear. Awareness of common diagnostic errors can ensure accurate diagnosis of meniscal tears. Online supplemental material is available for this article. ©RSNA, 2014.Radiographics 07/2014; 34(4):981-999. · 2.73 Impact Factor