Liang Dawei, Sun Jian, Wei Fangyuan, Zhang Jianzhong, Li Pengcui, Xu Yingke, Shang Xianwen, Deng Jin, Zhao Ting, Wei Lei
Department of Orthopaedics, The Second Hospital of Shanxi Medical University, Taiyuan, China.
Foot and Ankle Orthopaedic Surgery Center, Beijing Tongren Hospital, Beijing, China.
BMC Musculoskelet Disord. 2017 Nov 17;18(1):464. doi: 10.1186/s12891-017-1821-9.
Malleolar fracture, which is present in 37-53% of human ankle osteoarthritis (OA), is the most common type of fracture in the ankle joint. In spite of this, no rat animal model has been developed for this type of injury to date. Here, we established a rat ankle post-traumatic OA (PTOA) model induced by malleolar fracture; this model will be useful in ankle OA research.
Two-month-old male Sprague Dawley (SD) rats were randomized into 2 groups (n = 19 per group): 1) malleolus articular fracture, dislocation, and immediate reduction on the right joints and 2) malleolus articular fracture on the right ankle. The contralateral ankle joints were used as controls. The fracture and healing processes were confirmed and monitored by radiography. Changes in inflammation were monitored in vivo by fluorescence molecular tomography (FMT). Cartilage damage and changes in expression of OA-related genes were analyzed by histology, immunohistochemistry, Real-time quantitative PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA) at 8 weeks post-surgery.
X-rays showed that all fractures were healed at 8 weeks post-surgery. A reproducible, mild to moderate degree of OA cartilage damage with reduced aggrecan was detected by histology in all animals in both groups but there was no significant difference between the two groups. Decreased Col-II and increased Col-X and MMP-13 levels were detected by qPCR, immunohistochemistry, ELISA and FMT from both groups cartilage.
Malleolus articular fracture alone induces ankle OA with lesions on the central weight bearing area of the tibiotalar joint in rats. This model will provide a reproducible and useful tool for researchers to study ankle OA.
踝关节骨折是踝关节最常见的骨折类型，在人类踝关节骨关节炎（OA）中占37%-53%。尽管如此，迄今为止尚未建立针对这种损伤类型的大鼠动物模型。在此，我们建立了一种由踝关节骨折诱导的大鼠创伤后骨关节炎（PTOA）模型；该模型将有助于踝关节OA的研究。
将2月龄雄性Sprague Dawley（SD）大鼠随机分为2组（每组n = 19）：1）右侧关节进行踝关节面骨折、脱位并立即复位；2）右侧踝关节进行踝关节面骨折。对侧踝关节作为对照。通过X线摄影确认并监测骨折和愈合过程。通过荧光分子断层扫描（FMT）在体内监测炎症变化。在术后8周通过组织学、免疫组织化学、实时定量聚合酶链反应（qPCR）和酶联免疫吸附测定（ELISA）分析软骨损伤和OA相关基因表达的变化。
X线显示术后8周所有骨折均愈合。组织学检测发现两组所有动物均出现了可重复的、轻度至中度的OA软骨损伤，且聚集蛋白聚糖减少，但两组之间无显著差异。通过qPCR、免疫组织化学、ELISA和FMT检测发现两组软骨中Ⅱ型胶原减少，Ⅹ型胶原和基质金属蛋白酶-13水平升高。
单纯踝关节面骨折可诱导大鼠距骨中央负重区发生病变的踝关节OA。该模型将为研究人员提供一种可重复且有用的工具来研究踝关节OA。
