USE OF TWO SLICE TOUCH RULE IN MR DIAGNOSIS OF MENISCAL TEARS IN TRAUMA, TAKING ARTHROSCOPY AS GOLD STANDARD

Abstract

Background: Meniscal injuries are among the most common knee pathologies resulting from trauma, often requiring precise diagnosis for effective management. Magnetic Resonance Imaging (MRI) has emerged as a non-invasive modality for evaluating meniscal tears, with the two-slice touch rule offering a simplified diagnostic criterion. Despite its widespread use, variability in diagnostic performance necessitates further validation against arthroscopy, the gold standard, particularly in diverse populations with traumatic knee injuries.

Objective: To determine the diagnostic accuracy of MRI using the two-slice touch rule for detecting meniscal tears following knee trauma, using arthroscopy findings as the reference standard.

Methods: A prospective cross-sectional validation study was conducted at the Department of Radiology, Armed Forces Institute of Radiology and Imaging, Rawalpindi, from May 2023 to May 2024. A total of 120 patients, aged 18 to 80 years, clinically suspected of having meniscal tears due to trauma, were enrolled. MRI was performed using a 1.5 Tesla scanner with a dedicated knee coil. Imaging criteria included hyperintense signal extending to the articular surface on at least two consecutive slices. Arthroscopies were performed by an experienced orthopedic surgeon. Data were recorded and analyzed using SPSS version 25.0. Diagnostic accuracy metrics including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using a 2×2 contingency table.

Results: The study population had a mean age of 46.39 ± 15.45 years, with 76.7% males. MRI identified meniscal tears in 64.2% (n=77) of cases, while arthroscopy confirmed 60.8% (n=73). The sensitivity, specificity, PPV, and NPV of MRI were 83.56%, 65.96%, 79.22%, and 72.09%, respectively. The overall diagnostic accuracy of MRI was 76.67%.

Conclusion: MRI demonstrated substantial reliability as a diagnostic tool for meniscal tears using the two-slice touch rule, providing a valuable, non-invasive alternative to arthroscopy in the evaluation of traumatic knee injuries.