Quantitative analysis of experimental animals Forty rabbits were all included in result analysis. ELISA detection of inflammatory factor levels in serum Compared with the control group, the levels of interleukin-1, interleukin-6 and tumor necrosis factor-α were all increased in the other four groups (P < 0.01). Compared with the model group, the levels of interleukin-1, interleukin-6 and tumor necrosis factor-α were lowered significantly in the combined, sodium hyaluronate and PRP groups (P < 0.01 or P < 0.05), and the most significant decline was in the combined group (Table 1)."

Light microscope observation of the articular cartilage In the combined group, the cartilage tissues were stained uniformly, chondrocytes were full and arranged in neat that gathered together, some cells appeared to have karyopyknosis (Figures 1A, B). In the control group, the cartilage matrix was pink and stained uniformly, and cells were full and arranged in neat (Figures 1C, D). In the PRP group, the cartilage matrix was evenly colored, sparse cell arrangement was found, cell clusters were visible and some cells were concentrated (Figures 1E, F). In the sodium hyaluronate group, the cartilage tissues became thinning, some chondrocytes exhibited hypertrophy, cell arrangement was more disordered, there were cell clusters, even damaged cells, and some cells were concentrated (Figures 1G, H). In the model group, the cartilage tissues became significantly thinner, presenting with extensive surface fragmentation and exfoliation, fissures reached deep into the subchondral bone, the matrix was colored slightly, there were cell clusters and local cell damage, cell arrangement was the most disordered and sparse, a plurality of chondrocytes gathered together, and karyopyknosis was found (Figures 1I, J)."