Table 1 The dual role of infrapatellar fat pad in the joint

Evidence for a protective role of IFP in the knee

IFP is preserved even under extreme emaciation conditions.

[2]

Downregulation of NO production, glycosaminoglycan release, and MMP1 expression in cartilage by FCM from IFP

[43]

Presence of specialized pro-resolving lipid mediators and their precursors in ACM/FCM from IFP

[36, 37]

Presence of MSCs and macrophages with anti-inflammatory characteristics in IFP

[29, 43, 54]

Evidence for an inflammatory role of IFP in the knee

IFP inflammation as observed on MRI is associated with knee pain

[29]

Increased pro-inflammatory cytokine secretion by IFP is correlated with BMI

[53]

Increased fibrosis by synoviocytes under influence of FCM

[24]

Increased cytokine production and proliferation of Th1 cells under influence of ACM from IFP

[51]

Increased collagen release and MMP1 and MMP13 expression

[29]