OBJECTIVE To compare the unilateral signs of knee osteoarthritis (KOA) 30 and 60 days after anterior cruciate ligament transection (ACLT). Pain, gait function, synovial fluid inflammation, and histopathological changes in the synovial membrane were analyzed, as well as the interaction between the variables. MATERIALS AND METHODS Male Wistar rats (n = 32; 219.2 ± 18.6 g) were randomly distributed into four groups of eight animals each. Two groups were submitted to unilateral ACLT surgery to induce KOA and analyzed after 30 (KOA30) and 60 days (KOA60). Two control groups (without surgery) were also assessed after the same time periods (C30 and C60). All the groups were evaluated before ACLT from the least to most stressful tests (skin temperature, mechanical response threshold, gait test, thermal response threshold, and joint swelling), as well as 30 and 60 days after surgery. After euthanasia, the synovial fluid and synovial membrane were collected. RESULTS Thirty days after ACLT, KOA30 showed decrease paw print area and mechanical response threshold, higher joint swelling, skin temperature, leukocyte count, cytokine levels, and synovitis score. No differences were found between KOA30 and KOA60. CONCLUSION Our data showed that 30 days after ACLT is sufficient to induce signs of KOA in rats, such as pain, functional impairment, and synovial inflammation, suggesting that a shorter time period can be used as an experimental model.

中文翻译：

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前十字韧带横切后的30天足以诱发大鼠膝骨关节炎的体征：疼痛，功能障碍和滑膜炎症。

目的比较膝关节前交叉韧带切除术（ACLT）后30天和60天的膝骨关节炎（KOA）的单侧体征。分析疼痛，步态功能，滑液发炎和滑膜的组织病理学变化，以及变量之间的相互作用。材料与方法雄性Wistar大鼠（n = 32； 219.2±18.6 g）随机分为四组，每组八只动物。两组接受单侧ACLT手术以诱导KOA，并在30天（KOA30）和60天（KOA60）后进行分析。在相同时间段后（C30和C60）也评估了两个对照组（无手术）。从最低压力测试到最高压力测试（皮肤温度，机械反应阈值，步态测试，热反应阈值和关节肿胀）之前，对所有组进行评估。以及手术后30天和60天。安乐死后，收集滑液和滑膜。结果ACLT治疗30天后，KOA30显示爪印面积和机械反应阈值降低，关节肿胀，皮肤温度，白细胞计数，细胞因子水平和滑膜炎评分升高。在KOA30和KOA60之间没有发现差异。结论我们的数据显示ACLT后30天足以诱发大鼠KOA迹象，例如疼痛，功能障碍和滑膜炎症，这表明可以将较短的时间用作实验模型。白细胞计数，细胞因子水平和滑膜炎评分。在KOA30和KOA60之间没有发现差异。结论我们的数据显示ACLT后30天足以诱发大鼠KOA迹象，例如疼痛，功能障碍和滑膜炎症，这表明可以将较短的时间用作实验模型。白细胞计数，细胞因子水平和滑膜炎评分。在KOA30和KOA60之间没有发现差异。结论我们的数据显示ACLT后30天足以诱发大鼠KOA迹象，例如疼痛，功能障碍和滑膜炎症，这表明可以将较短的时间用作实验模型。