Wang Binggang, Lang Yanfei, Zhang Liu
Department of Orthopedic Surgery, Hebei Medical University, Shijiazhuang, China.
Department of Orthopedic Surgery, The Affiliated Hospital of North China University of Science and Technology, Tangshan, China.
Knee. 2019 Jan;26(1):2-13. doi: 10.1016/j.knee.2018.06.010. Epub 2018 Nov 8.
The purpose of this study was to characterise the histopathological changes in the infrapatellar fat pad (IPFP) in the early stage of patellofemoral osteoarthritis (PFOA).
Sixty-four New Zealand white rabbits were randomly divided into experimental (n = 24), sham (n = 16), and control groups (n = 24). In the experimental group, denoted as the patellar ligament uneven shortening group (US group), the patellar ligament (PL) was folded eight millimetres and sutured. After eight weeks, all animals were euthanised, and magnetic resonance imaging (MRI) evaluation, wet IPFP weight measurement, and histopathological and immunohistochemistry analysis were performed to analyse the histopathological changes in the IPFPs.
The maximum cross-sectional area (CSA) of the IPFPs in the sagittal position of MRI in the control group, sham group, and US group were 45.50 ± 7.19 mm, 45.88 ± 6.60 mm (vs. control group, P = 0.907), and 53.83 ± 8.24 mm (vs. control group, P = 0.015; vs. sham group, P = 0.035), respectively. The MRI intensity of the IPFPs in the control group, sham group, and US group were 115.53 ± 28.85, 108.53 ± 26.73 (vs. control group, P = 0.589), and 154.52 ± 18.48 (vs. control group, P = 0.002; vs. sham group, P = 0.002), respectively. The wet weight of the IPFPs in the control group, sham group, and US group were 0.32 ± 0.05 g, 0.32 ± 0.04 g (vs. control group, P = 0.895), and 0.38 ± 0.06 g (vs. control group, P = 0.017; vs. sham group, P = 0.033), respectively. The Osteoarthritis Research Society International (OARSI) scores of the IPFPs in the US group were 6.00 ± 1.91, which was higher than the scores of 2.50 ± 2.02 (P < 0.001) in the control group and of 2.75 ± 1.67 (P = 0.001) in the sham group.
The histopathological changes of the IPFPs as determined via MRI and microscopic structure appeared to occur much earlier than cartilage damage in PFOA. Furthermore, detecting and treating the IPFP changes may offer aid in the diagnosis and treatment of PFOA.
本研究旨在描述髌股关节炎（PFOA）早期髌下脂肪垫（IPFP）的组织病理学变化。
64只新西兰白兔随机分为实验组（n = 24）、假手术组（n = 16）和对照组（n = 24）。实验组为髌韧带不均匀缩短组（US组），将髌韧带（PL）折叠8毫米并缝合。8周后，对所有动物实施安乐死，进行磁共振成像（MRI）评估、IPFP湿重测量以及组织病理学和免疫组织化学分析，以分析IPFP的组织病理学变化。
对照组、假手术组和US组IPFP在MRI矢状位的最大横截面积（CSA）分别为45.50±7.19平方毫米、45.88±6.60平方毫米（与对照组相比，P = 0.907）和53.83±8.24平方毫米（与对照组相比，P = 0.015；与假手术组相比，P = 0.035）。对照组、假手术组和US组IPFP的MRI信号强度分别为115.53±28.85、108.53±26.73（与对照组相比，P = 0.589）和154.52±18.48（与对照组相比，P = 0.002；与假手术组相比，P = 0.002）。对照组、假手术组和US组IPFP的湿重分别为0.32±0.05克、0.32±0.04克（与对照组相比，P = 0.895）和0.38±0.06克（与对照组相比，P = 0.017；与假手术组相比，P = 0.033）。US组IPFP的国际骨关节炎研究学会（OARSI）评分为6.00±1.91，高于对照组的2.50±2.02（P < 0.001）和假手术组的2.75±l.67（P = 0.001）。
通过MRI和微观结构确定的IPFP组织病理学变化似乎比PFOA中的软骨损伤更早出现。此外，检测和治疗IPFP变化可能有助于PFOA的诊断和治疗。
