|Year : 2020 | Volume
| Issue : 3 | Page : 109-111
Arthroscopic correlation of ligamentous injury in adult knee with magnetic resonance imaging
Rahul Kumar Gupta, Shubhda Sagar, Arunim Swarup, Abhay Shankar Dube, Avinash Kumar, Avinash Rastogi
Department of Orthopaedic Surgery, Netaji Subhash Chandra Bose Subharti Medical College, Swami Vivekanand Subharti University, Meerut, Uttar Pradesh, India
|Date of Submission||05-Mar-2020|
|Date of Decision||29-May-2020|
|Date of Acceptance||06-Jul-2020|
|Date of Web Publication||31-Dec-2020|
Department of Radio Diagnosis, Netaji Subhash Chandra Bose Subharti Medical College, Swami Vivekanand Subharti University, Meerut, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Background: The purpose of this study was to compare the magnetic resonance imaging (MRI) and arthroscopic findings of internal derangement of adult knee joint. Aims and Objective: The objective was also to find out the value of MRI in the finding of ligamento-meniscal injury in adult knee joint during arthroscopy. Material and method: Ligamento-meniscal injury in 45 patients was subjected to MRI evaluation using hospital Sigma contour MRI with a field strength of 1.5 Tesla using 4-mm slice thickness, and those who had significant ligamento-meniscal findings underwent diagnostic and/or therapeutic arthroscopic procedure. Result: The sensitivity and specificity of MRI and arthroscopic findings of these injuries were found for medial meniscus to be 95.83% and 76.19%; for lateral meniscus 86.67% and 90%; for anterior cruciate ligament 97.37% and 85.71%; and posterior cruciate ligament 100% and 97.67%, respectively. Conclusion: The authors maintained that while arthroscopy, though invasive, is the gold standard to diagnose ligamento-meniscal injury, MRI is a noninvasive modality with high sensitivity and specificity for diagnosis and can be done to avoid arthroscopy, which should be best used for the therapy of significant ligamento-meniscal injuries.
Keywords: ACL- Anterior cruciate ligament, MRI- Magnetic resonance imaging, PCL- posterior cruciate ligament
|How to cite this article:|
Gupta RK, Sagar S, Swarup A, Dube AS, Kumar A, Rastogi A. Arthroscopic correlation of ligamentous injury in adult knee with magnetic resonance imaging. J Orthop Dis Traumatol 2020;3:109-11
|How to cite this URL:|
Gupta RK, Sagar S, Swarup A, Dube AS, Kumar A, Rastogi A. Arthroscopic correlation of ligamentous injury in adult knee with magnetic resonance imaging. J Orthop Dis Traumatol [serial online] 2020 [cited 2021 Jan 17];3:109-11. Available from: https://www.jodt.org/text.asp?2020/3/3/109/305741
| Introduction|| |
Knee joint stability depends on its supporting soft tissue structures and ACL, PCL, collateral ligaments and menisci. Knee joint is subjected to different forces as varus, valgus, compression and rotational forces, which in disproportionate manner result in different ligamento- meniscal injury. The assessment of these ligamento-meniscal injuries begins with clinical evaluation followed by diagnostic evaluation such as magnetic resonance imaging (MRI) and arthroscopy. MRI scan being noninvasive in nature is popularly used in imaging and evaluation of soft-tissue injury around knee, but arthroscopy is a proven gold standard for diagnostic and therapeutic purposes with almost 95% accuracy. Even being most accurate, diagnostic arthroscopy of knee has its disadvantage due to its inherent invasive nature.
| Materials and Methods|| |
This prospective study was conducted in the department of orthopedic surgery on 45 patients presented clinically with ligamento-meniscal injury during 2017 to 2019. Their MRI and arthroscopic findings were analyzed. The institutional ethics committee guidelines were followed during the study.
Inclusion and exclusion criteria
All presenting recent adult knee injuries, except those with contraindications to MRI who were suggested diagnostic or therapeutic arthroscopic procedures, were included in the study. Pre-existing knee diseases such as Grade III and IV osteoarthritis, neoplasm, inflammations, and infections and knees with previous arthroscopic reconstructions were excluded from the study.
To minimize interobservational variance, all MRI films were evaluated by the same radiologist and the same group of arthroscopic surgeons documented their findings. Each structural injury was considered individually.
A total of 45 patients with suspected ligamento-meniscal injury were studied using 1.5 T with 4-mm slice thickness. The standard imaging planes were the direct coronal, sagittal, and axial views. An axial acquisition through patellofemoral joint is used as an initial localizer for subsequent sagittal and coronal plane images. The knee is externally rotated 15°–20° and flexed 5°–10° in order to facilitate the visualization of ACL completely on sagittal images. MRI was performed within the period of 1–8 days of injury, and arthroscopy was performed within 3 weeks of time lag with MRI.
The procedures were carried out in the departmental operation theater by a group of arthroscopic surgeons in the selected cases as indicated for diagnostic or therapeutic purposes using standard antero-lateral and antero-medial portals. Arthroscope used in the above procedures was of 4 mm scope with 300 angle.
| Results|| |
The information obtained by MRI and arthroscopic evaluation was documented and analyzed under the following headings; type of structural injury, frequency of structural injury, and specificity and sensitivity of MRI for particular structural injury as confirmed by arthroscopy.
A total of 45 patients were enrolled in this study that underwent MRI evaluation and arthroscopic correlation with suspected ligamento-meniscal injury due to significant trauma either due to sport or road traffic accidents. Out of the 45 patients, 38 were male and seven were female; 26 had involvement of the right knee, whereas 19 had left knee involvement. Patients' age range was 17–46 years. On MRI, 38 patients were diagnosed with ACL injury, 28 with medial meniscus (MM) injury, 16 with lateral meniscus (LM) injury, and 2 patients had PCL injury.
In this study, the most common structural injury was ACL injury followed by MM injury, LM injury, and PCL injury, which were diagnosed by MRI and arthroscopically, as shown in [Table 1].
|Table 1: Total structural injuries of anterior cruciate ligament, posterior cruciate ligament, medial, and lateral meniscus involvement on magnetic resonance imaging and arthroscopy|
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Anterior cruciate ligament tear
MRI showed 38 ACL tears, whereas arthroscopy showed 37 ACL tears, with the following values: true positive – 37, true negative – 6, false-positive – 1, false-negative – 1, sensitivity – 97.37%, and specificity – 85.71%.
Medial meniscus tear
MRI showed 28 MM tears, whereas arthroscopy showed 23 MM tears with the following values: true positive – 23, true negative – 16, false-positive – 5, false-negative – 1, sensitivity – 95.83%, and specificity – 76.19%.
Lateral meniscus tear
MRI showed 16 LM tears, whereas arthroscopy showed 13 LM tears, with the following values: true positive – 13, true negative – 27, false-positive – 3, false-negative – 2, sensitivity – 86.67%, and specificity – 90%.
Posterior cruciate ligament tear
MRI showed 2 PCL tears and arthroscopy also showed 2 PCL tears, with the following values: true positive – 2, true negative – 42, false-positive – 1, false-negative – 0, sensitivity – 100%, and specificity – 97.67% [Table 2].
|Table 2: Summarized data analysis of magnetic resonance imaging and arthroscopy|
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| Discussion|| |
In our study, 38 ACL injuries were detected on MRI compared with the arthroscopic findings of 37 ACL tears with sensitivity and specificity of 97.37% and 85.71%, respectively, which is similar to the study conducted by Polly et al. The accuracy of selective magnetic resonance imaging compared with the findings of arthroscopy of the knee with sensitivity and specificity 100% and 98.7% respectively and similar study conducted by Richard et al in a Diagnostic performance of volume and limited oblique MRI of the anterior cruciate ligament compared to knee arthroscopy with similar result of 100% sensitivity and 97.1% of specificity. Spiers et al. also compared MRI finding of ACL tear with arthroscopic finding and showed 100% sensitivity and 98% specificity as compared with the study of Boeree et al. with 97% of sensitivity and 89% of specificity. The difference in the results of the above study in comparison to our study may be attributed to the presence of edema of knee joint in cases of acute injury [Table 3].
|Table 3: Magnetic resonance imaging and arthroscopic correlation of cruciate ligaments and meniscus injury of various literature|
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In this study, two suspected cases of PCL injury were identified, which were diagnosed on MRI and confirmed on arthroscopy with 100% sensitivity and 97.67% specificity; these results are comparable to the study of Polly et al., which compared PCL injury diagnosed by MRI and arthroscopy and showed 100%sensitivity and specificity and to that of Spiers et al. who compared PCL injury with the study of Boeree et al. with 96.7% sensitivity and 91.3% specificity as diagnosed by MRI evaluation and arthroscopy evaluation and showed 100% sensitivity and 98% specificity. This high specificity and sensitivity in our result may be due to the small sample size of PCL injury.
In our study, MRI detected 28 MM injuries and arthroscopy detected 23 MM injuries with sensitivity and specificity of 95.83% and 76.19%, respectively. Our study was compared with poly et al which compared diagnostic accuracy of medial meniscus on MRI and arthroscopy and showed sensitivity and specificity 96% and 100% respectively. Another study compared by Spiers et al comparing medial meniscus injury diagnosed by MRI and arthroscopy with 100% and 98% respectively. The low specificity of diagnosing meniscus tears by MRI may be due to Grade I and II tears which are often not seen on arthroscopy and also because most of the cases in our study have gone for MRI evaluation in the acute phase of injury.
In this study, MRI detected 16 LM injuries and arthroscopy showed 13 LM injuries with sensitivity and specificity of 86.67% and 90%, respectively. Similar study conducted by Spiers et al which compared MRI and arthroscopic findings of lateral meniscus injury with 99% accuracy which is comparable with other study conducted by Boeree et al and singh et al. in 2004, the sensitivity and specificity of LM injury were 87% and 99.29% respectively. The low sensitivity and specificity was again attributed to the possible edema in acute phases of injury and the presence of associated injuries, which might have attributed to the low sensitivity.
| Conclusion|| |
In this study, it is concluded that MRI has high sensitivity and comparable low specificity in the diagnosis of intra-articular injuries, which suggests underdiagnosis of injuries that may be a diagnosis bias due to intra-articular hematoma and Grade I and Grade II meniscal tear, which are often missed in acute cases of trauma. In our opinion, MRI being noninvasive in nature, is the investigation of choice to evaluate the internal derangement of knee joint provided that it should be done after the subsidence of knee edema. Still, arthroscopy is the best modality to diagnose ligamento-meniscal injuries.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
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[Table 1], [Table 2], [Table 3]