Meniscal injuries are among the most common internal derangements of the knee joint and represent an important cause of pain, swelling, mechanical symptoms, and functional impairment. The menisci are essential fibrocartilaginous structures that contribute significantly to knee joint biomechanics by improving load distribution, absorbing shock, enhancing joint stability, and protecting the articular cartilage.[1] Disruption of meniscal integrity, particularly through root tears or loss of meniscal tissue following meniscectomy, results in increased tibiofemoral contact pressure, altered joint mechanics, and accelerated cartilage degeneration, eventually predisposing patients to early osteoarthritis. Therefore, accurate identification and characterization of meniscal injuries are crucial for selecting appropriate treatment strategies and preventing long-term joint deterioration.[2]Meniscal tears may occur following acute rotational trauma, sports-related injuries, ligamentous injuries, or degenerative changes associated with aging.[3] Clinical diagnosis based on history and physical examination remains the initial approach; however, overlapping symptoms and frequent coexistence with other intra-articular abnormalities may make accurate diagnosis challenging. Knowledge of tear morphology, anatomical location, and associated injuries is essential because management decisions vary from conservative treatment and rehabilitation to arthroscopic repair or partial meniscectomy.[4,5]Magnetic resonance imaging (MRI) has emerged as the preferred non-invasive imaging modality for evaluating suspected meniscal pathology due to its superior soft tissue contrast, multiplanar imaging capability, and ability to assess associated ligamentous, cartilage, and bone abnormalities. MRI criteria for meniscal tears include abnormal increased signal intensity extending to the articular surface, altered meniscal contour, displaced fragments, and meniscal extrusion. The widespread availability and diagnostic capability of MRI have significantly reduced the need for diagnostic arthroscopy in routine cases.[6-9]Despite its high diagnostic value, MRI may demonstrate limitations in detecting certain meniscal lesions.[10,11] Small peripheral tears, meniscocapsular injuries, ramp lesions, and posterior horn root tears can be difficult to identify, resulting in missed diagnoses or false-positive interpretations. Previous studies have reported variable sensitivity and specificity of MRI for different tear patterns, with reduced accuracy particularly in patients with associated anterior cruciate ligament (ACL) injuries. Furthermore, MRI performance may vary depending on tear type, location, chronicity, imaging protocol, and radiologist expertise.[12]Arthroscopy remains the reference standard for definitive evaluation of meniscal injuries because it provides direct visualization of intra-articular structures and allows simultaneous therapeutic intervention. Comparing MRI findings with arthroscopic observations is essential to determine the true diagnostic performance of MRI and to identify specific lesions where imaging limitations persist.Therefore, the present study aims to evaluate the diagnostic accuracy of MRI in detecting meniscal injuries by comparing MRI findings with arthroscopic findings.

Study Design and Study Setting The present study was conducted as a prospective observational study to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) in detecting meniscal injuries by comparing MRI findings with arthroscopic findings. The study was carried out in the Department of Radiodiagnosis in collaboration with the Department of Orthopaedics at a tertiary care hospital. Study Population The study included patients who presented with clinical suspicion of meniscal injury and were subsequently evaluated with MRI of the knee followed by arthroscopic assessment. A total of 50 patients fulfilling the eligibility criteria were enrolled in the study. Inclusion Criteria Patients fulfilling the following criteria were included: • Patients with clinical suspicion of meniscal injury based on history and physical examination. • Patients who underwent MRI evaluation of the knee joint. • Patients who subsequently underwent diagnostic or therapeutic knee arthroscopy. • Patients willing to provide written informed consent for participation in the study. Exclusion Criteria Patients were excluded if they had: • Previous history of knee surgery. • Associated fractures or major traumatic bony injuries affecting MRI interpretation. • Advanced osteoarthritis with significant degenerative changes. • Contraindications to MRI examination. • Incomplete MRI or arthroscopic records. • Patients who did not undergo arthroscopic evaluation. Clinical Evaluation All patients were evaluated clinically before imaging. Detailed history regarding the mechanism of injury, duration of symptoms, pain, swelling, locking episodes, instability, and functional limitation was recorded. Physical examination included assessment of joint line tenderness, range of motion, and meniscal provocative tests such as McMurray test and Apley test. MRI Examination Protocol MRI examination of the affected knee was performed using a dedicated knee coil. Standard MRI sequences were obtained in multiple planes, including sagittal, coronal, and axial views. The MRI protocol included: • T1-weighted sequences for anatomical assessment. • Proton density-weighted and fat-suppressed sequences for detection of meniscal pathology. • T2-weighted sequences for evaluation of associated soft tissue abnormalities. MRI images were reviewed by experienced radiologists, and findings regarding meniscal tear presence, type, location, morphology, and associated injuries were recorded. MRI Assessment of Meniscal Injuries Meniscal injuries were evaluated based on established MRI criteria. A tear was considered present when abnormal increased signal intensity extended to the articular surface of the meniscus or when secondary signs such as meniscal extrusion, displaced fragments, or altered meniscal contour were observed. The following parameters were assessed: • Presence or absence of meniscal tear. • Involved meniscus (medial or lateral). • Anatomical location (anterior horn, body, posterior horn, or root region). • Tear pattern (horizontal, vertical, radial, complex, bucket-handle, or root tear). • Associated anterior cruciate ligament (ACL) injury. Arthroscopic Evaluation All patients underwent knee arthroscopy, which was considered the reference standard for diagnosis. Arthroscopic findings were documented regarding the presence, location, and type of meniscal injury. The arthroscopic diagnosis was compared with MRI findings for assessment of diagnostic accuracy. Outcome Measures The primary outcome measure was the diagnostic accuracy of MRI in detecting meniscal injuries compared with arthroscopic findings. The following diagnostic parameters were calculated: • Sensitivity • Specificity • Positive predictive value (PPV) • Negative predictive value (NPV) • Overall diagnostic accuracy The diagnostic performance of MRI was also evaluated according to tear type, anatomical location, and associated ACL injury status. Statistical Analysis Data obtained from clinical evaluation, MRI findings, and arthroscopic observations were entered into a structured database and analyzed SPSS. 25 . Continuous variables were expressed as mean ± standard deviation or median with interquartile range, as appropriate. Categorical variables were presented as frequencies and percentages.The diagnostic accuracy of MRI was calculated using arthroscopy as the reference standard. Sensitivity, specificity, PPV, NPV, and accuracy were calculated using standard diagnostic test evaluation methods. Agreement between MRI and arthroscopic findings was assessed using Cohens kappa coefficient. A p-value of <0.05 was considered statistically significant

A total of 50 patients with clinically suspected meniscal injuries were included in the study and evaluated using magnetic resonance imaging (MRI), with arthroscopic findings considered as the reference standard. The demographic characteristics, clinical presentation, MRI findings, and arthroscopic correlation were analyzed.The mean age of the study participants was 34.6 ± 12.8 years, with the majority of patients belonging to the 21–40 years age group (56.0%). Patients aged >40 years constituted 28.0%, while 16.0% were ≤20 years of age. A male predominance was observed, with males accounting for 72.0% and females accounting for 28.0% of cases. Sports-related injuries were the most common mechanism of injury (36.0%), followed by road traffic accidents (28.0%), twisting injuries (24.0%), and degenerative/insidious onset cases (12.0%). Most patients presented within 3 months of symptom onset (44.0%) (Table 1).All patients presented with knee pain (100.0%). Joint line tenderness was the most common clinical examination finding, observed in 76.0% of patients, followed by swelling/effusion (64.0%), locking symptoms (48.0%), restricted knee movement (40.0%), and instability symptoms (36.0%). Among the clinical tests, the McMurray test was positive in 68.0% of patients, whereas the Apley test was positive in 56.0% of cases (Table 2). The distribution of clinical symptoms and examination findings is illustrated in Figure 1.Arthroscopy revealed meniscal tears in 44 out of 50 patients (88.0%), while 6 patients (12.0%) had no tear. Medial meniscus involvement was the most frequent finding, observed in 56.0% of cases, followed by lateral meniscus tears (28.0%) and combined medial and lateral meniscal tears (8.0%). Regarding anatomical location, the posterior horn was the most commonly affected region (48.0%), followed by the body (28.0%), anterior horn (12.0%), and root region (12.0%) (Table 3). The distribution of meniscal injuries according to arthroscopic findings is depicted in Figure 2.MRI findings were compared with arthroscopic observations for different tear patterns. Horizontal tears were identified in 24.0% of cases on both MRI and arthroscopy. Complex tears showed similar detection rates on MRI and arthroscopy (20.0%). Vertical/longitudinal tears were detected in 18.0% cases on MRI compared with 20.0% on arthroscopy. Radial tears and root tears showed slightly lower detection rates on MRI compared with arthroscopy (Table 4). The comparative distribution of different tear patterns identified by MRI and arthroscopy is shown in Figure 3.The sensitivity of MRI varied according to the type of meniscal tear. MRI demonstrated the highest sensitivity for detecting complex tears and bucket-handle tears (100% each). Sensitivity was 91.7% for horizontal tears and 90.0% for vertical/longitudinal tears. Lower sensitivity was observed for radial tears (83.3%) and root tears (83.3%) (Table 5).Among patients with associated ACL injury, 18 patients had arthroscopically confirmed meniscal tears, of which MRI correctly detected 16 cases, resulting in a diagnostic accuracy of 88.9%. In patients without ACL injury, MRI demonstrated higher diagnostic accuracy, correctly identifying 25 out of 26 arthroscopically confirmed tears (96.2%) (Table 6).Using arthroscopy as the reference standard, MRI correctly identified 42 true-positive cases and 3 true-negative cases. The false-positive and false-negative rates were 6.0% and 4.0%, respectively. MRI demonstrated a sensitivity of 95.5%, specificity of 50.0%, positive predictive value of 93.3%, negative predictive value of 60.0%, and overall diagnostic accuracy of 90.0%. Table 1: Baseline Demographic and Clinical Characteristics of Study Participants (n=50) Parameter Number (n) Percentage (%) Age group (years) ≤20 8 16.0 21–40 28 56.0 >40 14 28.0 Mean age (years) 34.6 ± 12.8 Sex Male 36 72.0 Female 14 28.0 Mode of injury Sports-related injury 18 36.0 Road traffic accident 14 28.0 Twisting injury 12 24.0 Degenerative/insidious onset 6 12.0 Duration of symptoms <3 months 22 44.0 3–6 months 16 32.0 >6 months 12 24.0 Table 2: Clinical Presentation and Examination Findings Among Study Participants (n=50) Clinical Parameter Number (n) Percentage (%) Knee pain 50 100.0 Joint line tenderness 38 76.0 Swelling/effusion 32 64.0 Locking symptoms 24 48.0 Restricted knee movement 20 40.0 Instability symptoms 18 36.0 Positive McMurray test 34 68.0 Positive Apley test 28 56.0 Table 3: Distribution of Meniscal Injuries According to Arthroscopic Findings (Gold Standard) (n=50) Arthroscopic Finding Number (n) Percentage (%) Presence of meniscal tear Medial meniscus tear 28 56.0 Lateral meniscus tear 14 28.0 Both medial and lateral meniscal tear 4 8.0 No meniscal tear 4 8.0 Location of tear Anterior horn 6 12.0 Body 14 28.0 Posterior horn 24 48.0 Root region 6 12.0 Table 4: Distribution of Meniscal Tear Patterns on MRI and Arthroscopy (n=50) Tear Pattern MRI Findings (n) Percentage (%) Arthroscopic Findings (n) Percentage (%) Horizontal tear 12 24.0 12 24.0 Vertical/longitudinal tear 9 18.0 10 20.0 Radial tear 5 10.0 6 12.0 Complex tear 10 20.0 10 20.0 Bucket-handle tear 4 8.0 4 8.0 Root tear 5 10.0 6 12.0 No tear detected 5 10.0 2 4.0 Total 50 100.0 50 100.0 Table 5: MRI Accuracy According to Type of Meniscal Tear Compared with Arthroscopy (n=50) Type of Meniscal Tear Arthroscopy Positive (n) MRI Detected (n) Sensitivity (%) Horizontal tear 12 11 91.7 Vertical/longitudinal tear 10 9 90.0 Radial tear 6 5 83.3 Complex tear 10 10 100.0 Bucket-handle tear 4 4 100.0 Root tear 6 5 83.3 Table 6: MRI Detection of Meniscal Tears According to Associated ACL Injury Status (n=50) ACL Status Number of Patients Arthroscopy Positive for Meniscal Tear MRI Correctly Detected Tear Diagnostic Accuracy (%) ACL injury present 18 18 16 88.9 ACL injury absent 32 26 25 96.2 Total 50 44 41 92.0

The present prospective comparative study evaluated the diagnostic accuracy of magnetic resonance imaging (MRI) in detecting meniscal injuries by comparing MRI findings with arthroscopic findings in 50 patients, with arthroscopy considered the reference standard. MRI demonstrated good diagnostic performance with sensitivity of 95.5%, specificity of 50.0%, PPV of 93.3%, NPV of 60.0%, and overall diagnostic accuracy of 90.0%, supporting its role as an effective non-invasive modality for preoperative assessment of meniscal pathology.The mean age of study participants was 34.6 ± 12.8 years, with most patients belonging to the 21–40 years age group (56.0%). Males predominated (72.0%), and sports-related injuries were the most common mechanism of trauma (36.0%), followed by road traffic accidents (28.0%) and twisting injuries (24.0%) (Table 1). Similar demographic patterns have been reported by Wang et al.[13], who observed that MRI evaluation of meniscal tears is frequently performed in young, physically active patients with traumatic knee symptoms and provides high diagnostic accuracy compared with arthroscopy.Clinical findings remain important in the initial evaluation of suspected meniscal injuries; however, they may not reliably distinguish meniscal tears from other intra-articular abnormalities. In the present study, knee pain was present in all patients (100%), followed by joint line tenderness (76.0%), swelling/effusion (64.0%), and locking symptoms (48.0%) (Table 2). McMurray and Apley tests were positive in 68.0% and 56.0% of cases, respectively, indicating the need for imaging confirmation before surgical intervention.Arthroscopy identified meniscal tears in 44 patients (88.0%). Medial meniscus involvement was most common (56.0%), followed by lateral meniscus tears (28.0%) and combined tears (8.0%) (Table 3). The posterior horn was the most frequently affected site (48.0%), followed by the body (28.0%). Similar findings were reported by El-Hagrasy et al.[14], who observed a predominance of medial meniscal tears, particularly involving the posterior horn, due to its anatomical vulnerability and reduced mobility.MRI showed good agreement with arthroscopy for different tear patterns. The detection accuracy was 91.7% for horizontal tears, 90.0% for vertical/longitudinal tears, 100% for complex tears, 100% for bucket-handle tears, 83.3% for radial tears, and 83.3% for root tears (Table 5). Complex and bucket-handle tears showed higher detection rates due to their characteristic morphology, whereas radial and root tears remained more challenging to identify.The diagnostic performance of MRI in the present study was comparable with previous literature. Bottomley et al.[15] reported MRI sensitivity of 90%, specificity of 83%, and accuracy of 89% for medial meniscal tears. Kim et al.[16] demonstrated high accuracy for lateral meniscal tears with sensitivity of 94.1%, specificity of 82.3%, and accuracy of 88.0%. A meta-analysis by Wang et al.[13] further confirmed excellent MRI diagnostic performance, reporting pooled AUC values of 0.97 for medial meniscus and 0.96 for lateral meniscus.MRI accuracy was slightly reduced in patients with associated ACL injury (88.9%) compared with those without ACL injury (96.2%) (Table 6). Associated ligamentous injury may alter knee anatomy and increase diagnostic difficulty. Joshi et al.[17] also reported reduced MRI sensitivity for meniscal tears in ACL-deficient knees, particularly for lateral meniscal lesions.

MRI demonstrated high diagnostic accuracy for detection of meniscal injuries when compared with arthroscopy, with excellent sensitivity and good overall agreement with the surgical findings. It was particularly effective in identifying complex and bucket-handle tears, while subtle lesions such as radial and root tears showed relatively lower detection rates. MRI serves as a valuable non-invasive preoperative imaging modality that assists in accurate diagnosis and surgical planning. However, correlation with clinical findings and awareness of potential limitations remain essential for optimal management of meniscal injuries. Limitations The study was conducted with a relatively small sample size of 50 patients, which may limit the generalizability of the findings. The diagnostic performance of MRI may have been influenced by variations in radiologist experience and imaging interpretation. Additionally, the study was performed at a single centre, and larger multicentric studies are required to validate the results. Certain complex meniscal lesions, such as root tears and subtle peripheral tears, may remain challenging to detect accurately on MRI

1. Musahl V, Citak M, O’Loughlin PF, Choi D, Bedi A, Pearle AD, et al. The effect of medial versus lateral meniscectomy on the stability of the anterior cruciate ligament-deficient knee. Am J Sports Med. 2010;38(8):1591-1597. 2. Kim DH, Lee GC, Kim HH, Cha DH. Correlation between meniscal extrusion and symptom duration, alignment, and arthritic changes in medial meniscus posterior root tear: research article. Knee Surg Relat Res. 2020;32:1-8. 3. Allaire R, Muriuki M, Gilbertson L, Harner CD. Biomechanical consequences of a tear of the posterior root of the medial meniscus: similar to total meniscectomy. J Bone Joint Surg Am. 2008;90(9):1922-1931. 4. Bae JY, Park KS, Seon JK, Kwak DS, Jeon I, Song EK, et al. Biomechanical analysis of the effects of medial meniscectomy on degenerative osteoarthritis. Med Biol Eng Comput. 2012;50(1):53-60. 5. Fairbank TJ. Knee joint changes after meniscectomy. J Bone Joint Surg Br. 1948;30:664-670. 6. Kim C, Bin SI, Kim JM, Lee BS, Kim TH. Progression of radiographic osteoarthritis after partial meniscectomy in degenerative medial meniscal posterior root tears was greater in varus- than in neutral-aligned knees: a minimum 5-year follow-up. Knee Surg Sports Traumatol Arthrosc. 2020;28(10):3443-3449. 7. Sharifah MIA, Lee CL, Suraya A, Johan A, Syed AFSK, Tan SP, et al. Accuracy of MRI in the diagnosis of meniscal tears in patients with chronic ACL tears. Knee Surg Sports Traumatol Arthrosc. 2015;23(3):826-830. 8. Krych AJ, Wu IT, Desai VS, Murthy NS, Collins MS, Saris DB, et al. High rate of missed lateral meniscus posterior root tears on preoperative magnetic resonance imaging. Orthop J Sports Med. 2018;6(4):2325967118765722. 9. De Smet AA, Graf BK. Meniscal tears missed on MR imaging: relationship to meniscal tear patterns and anterior cruciate ligament tears. Am J Roentgenol. 1994;162(4):905-911. 10. De Smet AA, Mukherjee R. Clinical, MRI, and arthroscopic findings associated with failure to diagnose a lateral meniscal tear on knee MRI. Am J Roentgenol. 2008;190(1):22-26. 11. Bumberger A, Koller U, Hofbauer M, Tiefenboeck TM, Hajdu S, Windhager R, et al. Ramp lesions are frequently missed in ACL-deficient knees and should be repaired in case of instability. Knee Surg Sports Traumatol Arthrosc. 2020;28(3):840-854. 12. Moreira J, Almeida M, Lunet N, Gutierres M. Ramp lesions: a systematic review of MRI diagnostic accuracy and treatment efficacy. J Exp Orthop. 2020;7:1-14. 13. Wang W, Li Z, Peng HM, Bian YY, Li Y, Qian WW, et al. Accuracy of MRI diagnosis of meniscal tears of the knee: a meta-analysis and systematic review. J Knee Surg. 2021;34(2):121-129. 14. El-Hagrasy AMA, Theckayil AJ, Khan MA, Khan HN, Butt AJ. Magnetic resonance imaging is an effective first-line noninvasive tool for meniscal tear detection: a retrospective comparative analysis with knee arthroscopy. Arthrosc Sports Med Rehabil. 2025;7(2):101065. 15. Bottomley J, Al-Dadah O. Diagnostic accuracy of magnetic resonance imaging in meniscal tears. Cureus. 2025;17(9):e92155. 16. Kim SH, Lee HJ, Jang YH, Chun KJ, Park YB. Diagnostic accuracy of magnetic resonance imaging in the detection of type and location of meniscus tears: comparison with arthroscopic findings. J Clin Med. 2021;10(4):606. 17. Joshi A, Singh N, Basukala B, Bista R, Tripathi N, Pradhan I, et al. Accuracy of magnetic resonance imaging for meniscal body tear in anterior cruciate ligament-deficient knees compared to anterior cruciate ligament-intact knee. J Arthrosc Surg Sports Med. 2021;2(1):18-25.