Accuracy of 64-section MDCT in the diagnosis of cruciate ligament tears

Abstract

Aim: To evaluate the accuracy of non-arthrographic 64-section multidetector computed tomography (CT) in the assessment of cruciate ligament tears. A secondary goal was to determine its accuracy in the diagnosis of additional soft-tissue injuries around the knee.

Materials and methods: Forty consecutive outpatients underwent same-day magnetic resonance imaging (MRI) and 64-slice multidetector CT (MDCT) of the knee in this prospective study. MDCT images were independently evaluated for integrity of the anterior (ACL) and posterior cruciate ligaments (PCL), medial and lateral menisci, and medial and lateral collateral ligaments. Recognised secondary signs of ACL tears were also documented. MRI images were subsequently assessed by two radiologists and a consensus reached.

Results: The sensitivity of MDCT for ACL tears was 87.5-100%, with a specificity of 100%. The presence of one or more secondary signs of ACL tears on MDCT had a sensitivity of 50-87.5% with a specificity of 100%. The sensitivity of MDCT for PCL tears was 0-25% with a specificity of 100%. The sensitivity for meniscal tears was 9.1-23.1% with a specificity of 96.3-100%.

Conclusion: 64-section MDCT has very high sensitivity and specificity for ACL tears and, as on MRI, secondary signs, such as buckling of the PCL, are also useful in their diagnosis. MDCT has a low sensitivity for other soft-tissue injuries at the knee; however, its high specificity indicates that apparent PCL, meniscal, and collateral ligament tears can reliably be treated as true-positive findings.