Association Between Infrapatellar Fat Pad Volume and Knee Structural Changes in Patients with Knee Osteoarthritis.
OBJECTIVE
The function of the infrapatellar fat pad (IPFP) in knee osteoarthritis (OA) remains uncertain. This study aimed to examine cross-sectional associations between IPFP volume and knee structures in patients with knee OA.


METHODS
The study included 174 patients with clinical knee OA (mean age, 55.5 yrs). Fat-suppressed 3-D T1-weighted spoiled gradient recall magnetic resonance imaging (MRI) was used to measure the IPFP and cartilage volume. T2-weighted fast spin echo MRI was used to assess cartilage defects and bone marrow lesions (BML). Radiographic knee osteophytes and joint space narrowing (JSN) were assessed using the Osteoarthritis Research Society International atlas.


RESULTS
After adjustment for potential confounders, greater IPFP volume was associated with greater tibial and patellar cartilage volume (all p < 0.05), and fewer cartilage defects at all sites (OR 0.88-0.91, all p < 0.05). IPFP volume was associated with presence of BML at lateral tibial and medial femoral sites (OR 0.88-0.91, all p < 0.05) and osteophytes at lateral tibiofemoral compartment (OR 0.88, p < 0.05). IPFP volume was not significantly associated with JSN.


CONCLUSIONS
Greater IPFP volume was associated with greater knee cartilage volume and fewer structural abnormalities, suggesting a protective role of IPFP size in knee OA.
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Jingyu
J
Cai
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Jianhua
J
Xu
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Kang
K
Wang
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Shuang
S
Zheng
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Fan
F
He
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Shuting
S
Huan
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Shengqing
S
Xu
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Hui
H
Zhang
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania.
Laura
L
Laslett
From the Department of Rheumatology and Immunology, Arthritis Research Institute, and the Department of Medical Images, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.J. Cai, MMed; J. Xu, MD; K. Wang, MD; S. Zheng, MMed; F. He, MMed; S. Huan, MMed; S. Xu, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; H. Zhang, MMed, Department of Medical Image, the First Affiliated Hospital of Anhui Medical University; L. Laslett, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University; C. Ding, MD, Department of Rheumatology and Immunology, Arthritis Research Institute, the First Affiliated Hospital of Anhui Medical University, and Menzies Institute for Medical Research, University of Tasmania. changhai.ding@utas.edu.au.
Changhai
C
Ding
D000273:Adipose Tissue / Q000473:pathology*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D000886:Anthropometry; D001315:Australia; D002358:Cartilage, Articular / Q000473:pathology*; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging* / Q000473:pathology*; D010329:Patella / Q000473:pathology*; D011379:Prognosis; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D014057:Tomography, X-Ray Computed / Q000379:methods
BONE MARROW LESION; CARTILAGE DEFECT; CARTILAGE VOLUME; INFRAPATELLAR FAT PAD; OSTEOARTHRITIS; OSTEOPHYTE