Sonological evaluation of medial knee injuries and its comparison with magnetic resonance imaging findings: A study

Abstract

Background: Ultrasonography (US) offers several unique strengths over MR imaging, that make it a promising technique for the evaluation of certain disorders of the knee. US has higher spatial resolution than MR imaging, which may be helpful in evaluating the superficial structures and popliteal fossaof the knee in detail. Visualizing the MCL under ultrasound is relatively easy due to its superficial location, spanning from the medial femoral condyle to the medial tibial metaphysis. Meanwhile MRI is costly, not advisable to all due to its claustrophobia and ferromagnetic property. Ultrasound (US) on the other hand is an inexpensive, widely available and non-invasive technique which also allows dynamic imaging Our objective is to assess the validity of ultrasound in the diagnosis of medial knee injuries in comparison with MRI findings. Materials and Methods: Patients attending Department of Orthopaedics is referred to Department of radiodiagnosis of T.D. Medical College Alappuzha, who were clinically suspected to have medial knee injury, during the study period. This study was a prospective study. Prospective patients with clinically suspected medial knee injuries scheduled for MRI of the knee were evaluated by Ultrasound examination prior to the MRI. Sonographic findings were then compared to MRI results. Results and Discussion: 60 patients were enrolled in the study. 73.3% of the study population were males (1) and most of them belonged in their 2nd and 3rd decades. Most of the injuries were left sided [60%] and majority [65%] presented for radiological evaluation within 1 week to 1 month of history of injury. Accuracy of ultrasound in the diagnosis of MCL and MM injuries were 86.7% and 85% respectively.US demonstrated 89.6% sensitivity and 75% specificity for medial collateral ligament (MCL) injuries and 85.3% sensitivity and 84.6% specificity for medial meniscus (MM) tears. The most frequent knee finding in this study was joint effusion which was seen in 50(83.3%) of patients. Conclusion: US gives high accuracy and specificity in detection of MCL and MM injuries. Ultrasound may have a role as the initial rapid imaging modality in patients with suspected MCL or medial meniscus injuries and it may serve as an effective low-cost screening tool for patients with MM or MCL injuries and avoid performing the high-cost MRI.