Abstract
Objectives: To evaluate the diagnostic accuracy of ultrasonography (US) in comparison with magnetic resonance imaging (MRI) for anterior knee pathologies, while also assessing their cost-effectiveness and clinical utility.
Methodology: This prospective comparative diagnostic accuracy study was conducted between January 2022 and March 2024 at a tertiary care center in Erbil, Iraq, enrolling 80 adult patients with isolated anterior knee pain (AKP) through consecutive sampling. All participants underwent both high-resolution US and MRI within two weeks. The imaging protocols focused on key anterior knee structures, enabling complementary evaluation of soft tissue, vascular, and osteochondral abnormalities, thereby strengthening the validity and clinical applicability of the comparative findings. Data were analyzed using the McNemar test and descriptive statistics to assess sensitivity, diagnostic performance, and cost-effectiveness.
Results: US demonstrated higher sensitivity than MRI for patellar tendinopathy (95% vs. 87%, p=0.04) and prepatellar bursitis (100% vs. 90%, p=0.03). Conversely, MRI outperformed US in detecting cartilage defects (93% vs. 70%, p<0.001) and trochlear dysplasia (91% vs. 35%, p<0.001). The US offered shorter median wait times (3.5 vs. 16.1 days), reduced scan duration (19.1 vs. 34.5 minutes), and 41% lower costs compared to MRI.
Conclusion: Ultrasonography offers distinct advantages in the evaluation of superficial soft tissue disorders of the anterior knee, demonstrating greater sensitivity in detecting early structural alterations such as tendon thickening, hypoechoic regions, and neovascularization. In contrast, MRI remains the preferred modality for assessing deeper structural and osteochondral abnormalities. Implementing a stepwise imaging approach, with ultrasonography as the initial modality, may enhance diagnostic efficiency while simultaneously reducing healthcare costs.

Key words: Cartilage, cost-benefit analysis, patellar tendinopathy, prepatellar bursitis.