Significance of Ultrasound in Assessment of Painful Knee: A Comparative Study to Magnetic Resonance Imaging

Abstract Background Knee pain is one of the most frequent symptoms that bring patients to the hospital. It affects approximately 25% of adults, with an increasing incidence nowadays the pain may result from the muscles, ligaments, tendons, and menisci, from trauma due to non-traumatic injuries like infection, bursitis, osteoarthritis, and tendinitis. Aim of the Work Aim of study is to evaluate the role of US in assessment of painful knee compared to conventional MRI sequences as an alternative cost-effective screening modality for an accurate diagnosis. Patients and Methods This study is a cross-sectional study was conducted at Ain Shams University Hospitals at Radiology department. Our study included forty patients complaining of acute knee pain from (1 day to 3 months’ duration). The main source of data for this study was the prospectively conducted scans and clinical history of the patients referred to the MRI section of the department of Radiology, Ain Shams University Hospitals at 6 months. Results Forty patients complaining of acute knee pain from. Every single one of them went through MRI and US assessments indiscriminately and independently, US succeeded in evaluating soft tissue structures pathologies including knee effusion, meniscal injury (degeneration, tear, and extrusion), MCL, LCL, bursitis. muscle, tendon injury and osteoarthritic changes. aside from the cruciate ligaments. US showed an overall sensitivity of 70.1% and specificity of 99.2% with accuracy of 95.2%. The overall PPV and NPV were 93.1% and 95.5% respectively. Conclusion US has proved that it can be used as an alternative cost effective screening modality for patients complaining of acute pain, US has reasonable sensitivity, specificity and accuracy in detecting knee effusion, meniscal injury including degeneration, tear, and extrusion, collateral ligaments, bursitis, baker cyst. Muscle, tendon injury and osteoarthritic changes, with no contraindications it can be used as the first choice in assessment of acute knee pain. MRI can be reserved for further workup if clinically warranted.