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Research progress in multimodal MRI for infrapatellar fat pad injuries in knee osteoarthritis
MA Zhenyue  LIU Kaijia  ZHANG Huimao  XIONG Wenji 

DOI:10.12015/issn.1674-8034.2026.05.033.


[Abstract] Early identification and intervention of knee osteoarthritis (KOA) are crucial for improving long-term patient prognosis. In recent years, as an important intra-articular soft tissue structure, the infrapatellar fat pad (IPFP) has garnered increasing attention due to its dual functions of mechanical cushioning and inflammatory regulation, highlighting its potential role in the onset and progression of KOA. Multiple studies suggest that imaging alterations in the IPFP are associated with radiological staging of KOA, structural joint damage, and certain clinical symptoms. Magnetic resonance imaging (MRI), owing to its excellent soft tissue resolution and multiparametric imaging capabilities, has become an essential imaging tool for evaluating IPFP pathologies in KOA. Therefore, this article systematically reviews the multimodal MRI manifestations of the IPFP in KOA, focusing on advances in conventional and functional MRI sequences for assessing its morphology, composition, and microstructural changes. It also evaluates the existing evidence and limitations regarding the correlation between IPFP imaging features and KOA progression, aiming to provide a reference for the rational application of IPFP-related imaging indicators and future research directions.
[Keywords] knee osteoarthritis；infrapatellar fat pad；disease progression；multimodal；magnetic resonance imaging

MA Zhenyue   LIU Kaijia   ZHANG Huimao   XIONG Wenji*  

Department of Radiology, the First Hospital of Jilin University, Changchun 130021, China

Corresponding author: XIONG W J, E-mail: xiongwj@jlu.edu.cn

Conflicts of interest   None.

Received  2026-01-21
Accepted  2026-04-10
DOI: 10.12015/issn.1674-8034.2026.05.033
DOI:10.12015/issn.1674-8034.2026.05.033.

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