To explore the method of replicating experimental animal model of knee osteoarthritis.
Knee osteoarthritis was replicated by modified Hulth's modeling method. X-ray photographic and transmission electron microscopic examination, test of the joint synovial fluid of the modeled joint were performed, and serum contents of malondialdehyde (MDA) and nitric oxide (NO) in blood were measured.
(1) In the normal control group, the articular surface is smooth and glossy, with intact cells and cellular membrane. In the model group, the medial space of the knee joint became obvious narrowed with rough and deformed articular surface and osteophytes, as well as the atrophic chondrocytes with pyknotic cell nucleus and broken cellular membrane. (2) Eight weeks and 16 weeks after modeling, in the model group, the contents of interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and matrix metalloproteinase-3 (MMP-3) in synovial fluid and the levels of serum MDA and NO were obviously raised, and the activity of superoxide dismutase (SOD) in synovial membrane was obviously lowered 16 weeks after modeling, showing significant difference when compared with those in the normal control group (P < 0.01).
Modified Hulth's modeling method in replicating knee osteoarthritis is simple in manipulation with less wound, and the condition of modeled knee joint could be maintained stable to certain degree, which is advantageous to the success of animal model replicating.