Objective: To observe the improvement effect of Anti-earthworm Tongbi-complex decoction on bone biomechanics of cartilaginous tissue on the rabbit models of knee osteoarthritis（KOA）

and elucidate its potential mechanism.Methods: Forty healthy male rabbits were randomly divided into four groups: normal control group

model group

Anti-earthworm Tongbi-complex decoction group and glucosamine hydrochloride capsules group.All rabbits were prepared for right knee osteoarthritis model induced by anterior cruciate ligament transaction except the normal control group.The model rabbits were treated with Anti-earthworm Tongbi-complex decoction（0.6 g·kg-1

ig） and glucosamine hydrochloride Capsules（0.1 g·kg-1

ig） for 4 weeks.The following indexes was observed in all rabbits at experimental endpoint like the ultrastructure changes of arthrodial cartilage and synovium

levels of interleukin-1β（IL-1β） and tumor necrosis factor-α（TNF-α） in synovial fluid by ELISIA

and the expression of matrix metallo-proteinase（MMP-1） and tissue inhibitor of tissue inhibitor of metalloproteinase-1（TIMP-1） by immunohistochemistry in cartilage tissue.Meanwhile

biomechanical test was performed to measure the maximal loading and compression modulus.Results: Compared with model group of OA

the indexes showed significant improvement in rabbits treated with Anti-earthworm Tongbi-complex decoction and glucosamine hydrochloride capsules group like the ultrastructure changes of arthrodial cartilage and synovium

levels of IL-1β and TNF-α in synovial fluid

the expression of MMP-1 and TIMP-1 in cartilage tissue

and biomechanical characters including the maximal loading and compression modulus.Conclusion: Ant-earthworm tongbi-complex decoction can decrease the levels of IL-1β and TNF-α in synovial fluid

improve the unbalancing expression of MMP-1 and TIMP-1 in articular chondrocytes

so as to protect cartilaginous tissue in the rabbit with knee osteoarthritis.