Comparative Study Of MRI And Arthroscopy For The Diagnosis Of Meniscal And Ligamentous Injuries Of The Knee Joint

BackgroundMagnetic Resonance imaging (MRI) is a frequently used, non-invasive investigation forthe diagnosis of knee meniscal and ligamentous injuries. Traumatic knee joint injury iscommon in young as well as old age group. Injury results in various intra-articular kneelesions and the diagnosis is not always easy. Even with the investigations, the diagnosisremains inconclusive some times. This study was designed to compare the accuracy of MRIby arthroscopic examination in patients with knee meniscal and ligamentous injuries. If MRIdiagnosis could be as accurate as arthroscopy, the need for this expensive and invasiveinvestigation could be avoided.ObjectiveTo compare the MRI and Arthroscopy diagnosis of meniscal and ligamentous injury ofknee joint.MethodThe study was done from January2011to December2011at China Japan UnionHospital (Third Clinical Hospital) of Jilin University. The total of32patients having kneetrauma and suspected of having meniscal and/or ligamentous injury who underwentpreoperative MRI followed by arthroscopy were selected as cases. Since every patient’smedical record including past and present illnesses, radiological examinations, treatments,and outcomes have been documented electronically in the hospital computer system. Thissystem provides valid information for retrospective analysis. MRI sequences includedsagittal fat suppression proton density, sagittal fat suppression T2, Sagittal T1, Coronal fatsuppression proton density and Coronal T1fat suppression echo. Standard protocols wereused for each of the sequences. Similarly, arthroscopy was performed using standardapproach. Sensitivity, specificity, accuracy, positive predictive value, negative predictivevalue, P value and kappa agreement measures were calculated.Results1. For MRI diagnosis of medial meniscus injury there were5true positives,2falsepositives,3false negatives and22true negatives. This meant accuracy of84.37%, sensitivity of62.50%, specificity of91.66%, negative predictive value of88.00%and positivepredictive value of71.42%with the good Kappa agreement of0.56.2. For MRI diagnosis of lateral meniscus injury there were6true positives,3falsepositives, no false negatives and23true negatives. This meant accuracy of90.06%,sensitivity of100%, specificity of88.46%, negative predictive value of100%and positivepredictive value of66.66%with substantial Kappa agreement of0.74.3. For MRI diagnosis of posterior cruciate ligament tear there were5cases diagnosed astear both by MRI and arthroscopy and27cases as normal posterior cruciate ligament. Thisgave us the accuracy, sensitivity, specificity, negative predictive value and positivepredictive value of100%with almost perfect Kappa agreement of1.0.4. For MRI diagnosis of anterior cruciate ligament tear there were13true positives, nofalse positives,2false negatives and17true negatives. This gave us accuracy of93%,sensitivity of86.67%, specificity of100%, negative predictive value of89.40%and positivepredictive value of100%with almost perfect Kappa agreement of0.87.ConclusionMRI shows high accuracy and can be used as a diagnostic tool to diagnose the clinicallysuspected meniscal and ligament injury of the knee joint.