Title : Reframing MRI of the pediatric knee: Evidence-based indications, diagnostic pitfalls, and emerging imaging biomarkers
Abstract:
Introduction: Magnetic Resonance Imaging (MRI) has become the primary advanced imaging modality for evaluating pediatric knee pathology because of its ability to assess soft tissues, cartilage, bone marrow, and physeal structures without ionizing radiation. However, the growing availability of MRI has led to increasing utilization and concerns regarding inappropriate use in children. In addition, interpretation of MRI in the skeletally immature knee remains challenging due to evolving anatomy, developmental variants, and injury patterns unique to the presence of open physes. The purpose of this review is to synthesize the current evidence regarding the clinical role of MRI in pediatric knee disorders and to highlight emerging imaging parameters that may improve diagnostic accuracy and clinical decision-making.
Methods: A narrative review of the literature was performed using peer-reviewed clinical studies, imaging investigations, and guideline-based recommendations related to MRI evaluation of pediatric knee pathology. Studies addressing imaging indications, diagnostic accuracy, developmental anatomy, and emerging MRI metrics were analyzed and integrated to provide a clinically oriented synthesis of the evidence.
Results: MRI provides high diagnostic accuracy for detecting ligamentous injuries, meniscal pathology, osteochondral lesions, inflammatory conditions, and radiographically occult physeal injuries in the pediatric knee. For example, MRI can reveal occult fractures in up to approximately one-third of children with persistent clinical suspicion despite negative radiographs. Nevertheless, MRI interpretation may be complicated by normal developmental findings and age-related signal variations, which can lead to diagnostic uncertainty or false-positive interpretations. Furthermore, increasing availability of MRI has contributed to inappropriate use as a screening tool in some clinical settings, despite evidence that clinical examination remains highly accurate when performed by experienced clinicians. Emerging MRI-based measurements, such as quantitative assessment of anterior tibial translation, may improve diagnostic confidence for injuries such as anterior cruciate ligament tears and may provide objective imaging biomarkers for clinical decision-making.
Conclusion: MRI is a powerful tool for evaluating pediatric knee disorders when used in conjunction with careful clinical assessment and appropriate initial imaging. Understanding developmental anatomy, recognizing diagnostic pitfalls, and integrating emerging quantitative MRI parameters may enhance diagnostic accuracy and optimize patient management. Future research should focus on developing evidence-based imaging algorithms and validated imaging biomarkers to further refine the role of MRI in the evaluation of the skeletally immature knee.
