Imaging of the Pediatric Knee

Area of Science:

• Pediatric Radiology
• Orthopedic Imaging
• Skeletal Development

Background:

• Immature knee imaging findings can mimic pathology or indicate areas of weakness.
• Understanding normal developmental variants is crucial for accurate diagnosis in pediatric patients.
• Age and skeletal maturation significantly influence knee joint imaging appearance.

Purpose of the Study:

• To review the developmental anatomy of the immature knee joint.
• To outline age- and maturation-dependent imaging considerations.
• To describe various developmental variants and their differentiation from pathology.

Main Methods:

• Review of developmental anatomy and imaging characteristics of the immature knee.
• Categorization of variants by anatomical compartment: tibiofemoral, patellofemoral, soft tissues, and osseous components.
• Discussion of differential diagnoses for common imaging mimics.

Main Results:

• Detailed description of tibiofemoral variants (e.g., FOPE, ossification variants, metaphyseal irregularities).
• Explanation of patellofemoral variants (e.g., partite patella, dorsolateral defect, overuse syndromes, avulsion fractures).
• Review of soft tissue (e.g., discoid meniscus, ACL variants) and osseous variants (e.g., fabella, meniscal ossicle).

Conclusions:

• Recognizing normal developmental variants in the immature knee is essential to avoid misdiagnosis.
• Distinguishing developmental variants from true pathology ensures appropriate patient management.
• This review provides a framework for interpreting complex pediatric knee imaging findings.