A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina sign
Abstract Background Diagnosing partial tears of the medial meniscus (MM) posterior root is difficult. 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 pa...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2021-10-01
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| Series: | Knee Surgery & Related Research |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s43019-021-00120-4 |
| _version_ | 1818880982906830848 |
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| author | Takayuki Furumatsu Takaaki Hiranaka Keisuke Kintaka Yuki Okazaki Naohiro Higashihara Masanori Tamura Toshifumi Ozaki |
| author_facet | Takayuki Furumatsu Takaaki Hiranaka Keisuke Kintaka Yuki Okazaki Naohiro Higashihara Masanori Tamura Toshifumi Ozaki |
| author_sort | Takayuki Furumatsu |
| collection | DOAJ |
| description | Abstract Background Diagnosing partial tears of the medial meniscus (MM) posterior root is difficult. 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. Methods Eighteen patients who had arthroscopically confirmed partial MMPRTs were included. As a control, 18 patients who underwent partial meniscectomy for other types of MM tears were evaluated. Isolated partial MMPRTs were classified into the following three types: type A, accurate partial stable tear (cleavage < 1/2 of root width); type B, bridged unstable root tear (cleavage ≥ 1/2 of root width); type C, complex horn tear expanded to the root. Conventional MRI-based findings of MMPRTs were evaluated between two groups (n = 23). Posterior root irregularity, bone marrow spot, and ocarina-like appearance showing several condensed circles in triangular meniscal horn (ocarina sign) were also evaluated. Results Posterior root irregularity and bone marrow spot were frequently observed in the partial MMPRTs (47.8%), compared with the other MM tears (P = 0.007 and 0.023, respectively). The ocarina sign was detected in 69.6% of patients with partial MMPRTs. A significant difference between two groups was observed in a positive ratio of ocarina sign (P < 0.001). Types A, B, and C of the partial tear/damage were observed in three, eight, and seven patients, respectively. The ocarina sign was the most common MRI finding in each type of partial MMPRT. Conclusions This study demonstrated that a characteristic MRI finding, “ocarina sign,” was frequently observed in patients with partial tear/damage of the MM posterior root. The ocarina sign was the most common MRI finding in several types of partial MMPRTs. Our results suggest that the ocarina sign may be useful to diagnose unnoticed partial MMPRTs. Level of evidence: IV, retrospective comparative study. |
| first_indexed | 2024-12-19T14:54:37Z |
| format | Article |
| id | doaj.art-3ad892f336924fd5a787e965d69f6dde |
| institution | Directory Open Access Journal |
| issn | 2234-2451 |
| language | English |
| last_indexed | 2024-12-19T14:54:37Z |
| publishDate | 2021-10-01 |
| publisher | BMC |
| record_format | Article |
| series | Knee Surgery & Related Research |
| spelling | doaj.art-3ad892f336924fd5a787e965d69f6dde2022-12-21T20:16:45ZengBMCKnee Surgery & Related Research2234-24512021-10-013311910.1186/s43019-021-00120-4A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina signTakayuki Furumatsu0Takaaki Hiranaka1Keisuke Kintaka2Yuki Okazaki3Naohiro Higashihara4Masanori Tamura5Toshifumi Ozaki6Department of Orthopaedic Surgery, Okayama University HospitalDepartment of Orthopaedic Surgery, Okayama University HospitalDepartment of Orthopaedic Surgery, Okayama University HospitalDepartment of Orthopaedic Surgery, Okayama University HospitalDepartment of Orthopaedic Surgery, Okayama University HospitalDepartment of Orthopaedic Surgery, Okayama University HospitalDepartment of Orthopaedic Surgery, Okayama University HospitalAbstract Background Diagnosing partial tears of the medial meniscus (MM) posterior root is difficult. 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. Methods Eighteen patients who had arthroscopically confirmed partial MMPRTs were included. As a control, 18 patients who underwent partial meniscectomy for other types of MM tears were evaluated. Isolated partial MMPRTs were classified into the following three types: type A, accurate partial stable tear (cleavage < 1/2 of root width); type B, bridged unstable root tear (cleavage ≥ 1/2 of root width); type C, complex horn tear expanded to the root. Conventional MRI-based findings of MMPRTs were evaluated between two groups (n = 23). Posterior root irregularity, bone marrow spot, and ocarina-like appearance showing several condensed circles in triangular meniscal horn (ocarina sign) were also evaluated. Results Posterior root irregularity and bone marrow spot were frequently observed in the partial MMPRTs (47.8%), compared with the other MM tears (P = 0.007 and 0.023, respectively). The ocarina sign was detected in 69.6% of patients with partial MMPRTs. A significant difference between two groups was observed in a positive ratio of ocarina sign (P < 0.001). Types A, B, and C of the partial tear/damage were observed in three, eight, and seven patients, respectively. The ocarina sign was the most common MRI finding in each type of partial MMPRT. Conclusions This study demonstrated that a characteristic MRI finding, “ocarina sign,” was frequently observed in patients with partial tear/damage of the MM posterior root. The ocarina sign was the most common MRI finding in several types of partial MMPRTs. Our results suggest that the ocarina sign may be useful to diagnose unnoticed partial MMPRTs. Level of evidence: IV, retrospective comparative study.https://doi.org/10.1186/s43019-021-00120-4Medial meniscusPosterior rootPartial tearMagnetic resonance imagingOcarina sign |
| spellingShingle | Takayuki Furumatsu Takaaki Hiranaka Keisuke Kintaka Yuki Okazaki Naohiro Higashihara Masanori Tamura Toshifumi Ozaki A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina sign Knee Surgery & Related Research Medial meniscus Posterior root Partial tear Magnetic resonance imaging Ocarina sign |
| title | A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina sign |
| title_full | A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina sign |
| title_fullStr | A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina sign |
| title_full_unstemmed | A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina sign |
| title_short | A characteristic MRI finding to diagnose a partial tear of the medial meniscus posterior root: an ocarina sign |
| title_sort | characteristic mri finding to diagnose a partial tear of the medial meniscus posterior root an ocarina sign |
| topic | Medial meniscus Posterior root Partial tear Magnetic resonance imaging Ocarina sign |
| url | https://doi.org/10.1186/s43019-021-00120-4 |
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