Abstract: Objective To explore the effect of extracorporeal shock wave (ESW) on expression of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in cartilage in rabbits with knee osteoarthritis. Methods 30 rabbits were randomly divided into control group, model group and treatment group, with 10 rabbits in each group. Model of knee osteoarthritis was established with modified plaster cast in extension position for 6 weeks except the control group, and the treatment group was treated with ESW (each 1000 impulse, the energy flux density of 0.1 mJ/mm2). The rabbits were sacrificed respectively 4 weeks after ESW treatment, the general and histological changes of articular cartilage were examined and immunohistochemical staining was used to observe the expression of IL-1β and TNF-α in cartilage. Results The expression of IL-1β and TNF-α were significantly lower in the treatment group than in the model group (P<0.01). Conclusion ESW can down-regulate the expression of IL-1β and TNF-α in chondrocytes with osteoarthritis.

Key words: osteoarthritis, extracoporeal shock wave, articular cartilage, interleukin-1β, tumour necrosis factor-α, rabbits