What is Beyond Chronic Knee Pain? A Comparative Ultrasound and MRI Study to Assess the Contribution of Various Pathological Entities in the Painful Knee Joint

Abstract Background: Chronic knee pain is a common increasing musculoskeletal complaint. As a result, selecting a dependable screening tool at a reasonable cost is essential. Although mag-netic resonance imaging (MRI) is the gold standard imaging modality for knee soft tissue structures, its high cost has led to widespread abuse. Aim of Study: The main aim of this study is to spot ultra-sonography's diagnostic efficacy as a quick imaging method for evaluating painful knee joints in comparison with MRI. Patients and Methods: A prospective study was conducted on 110 patients with clinically confirmed chronic knee pain/ limited mobility. Both ultrasonography and MRI examinations of the knee were done for all study groups. The diagnostic ef-fectiveness of ultrasonography in comparison to MRI was ex-amined for evaluating different findings of possible causes of chronic knee pain. Results: A total of 120 knees were included in the study; Ultrasonography and MRI reported 9 different pathological entities of possible causes of chronic knee pain or related to it. Joint effusion was the most common finding (91.6%) fol-lowed by OA changes (41.6%) and peri-articular baker cyst (25%). The overall sensitivity of ultrasonography was 85.5% and 100% specificity. The ultrasonography provided the highest sensitivity (100%) in detecting effusion,baker cyst, hematoma, torn menisci, Meniscal horn extrusion, vascular anomalies, and hemangioma, followed by periarticular cystic and solid lesions with sensitivities of 86.6% and 88.8% respectively. Conclusion: With the advantages of being widely acces-sible, affordable, and having no contraindications, ultrasound should be the primary imaging modality of choice when eval-uating chronic knee pain. It can be used as an effective and acceptable screening imaging modality. For ambiguous ultra-sound results, MRI can be reserved.