Change Of Biomechanical Mechanism In Rabbit' Knee Osteoarthritis After Immobilization And Interference By Acupotomy

Osteoarthritis6(OA) is an extremely common osteoarthropathy around the world, and is the concern of the medical institution due to the high disability rate which has important influence for patients'life and social activities. World Health Organization Assembly declared "Bone and Joint Decade"(2000-2010) In2000. Chinese Ministry of Health and Chinese Medical Association declared "Bone and Joint Decade in China"(2002-2012) in2002. Knee joint is the predilection site in OA. Knee Osteoarthritis (KOA) is characterized mainly by arthralgia, stiffness, and loss of motion. Doctors have recently got a good effect in clinical practice by using Acupotomy according the theory of force banlance, but the study of basic experiment progress little.ObjectiveIn this research we have analyzed the biomechanical alterations of the lateral ligament, medial collateral ligament and patellar ligament in pathogenesis of KOA. We want to explain the pathogenesis of KOA from miscuiature of12meridiains and force unbalance of knee joint which has already realized by the acupotomology too. At the same time, we paid more attention to the role of acupotomy intervention in this course.MethodsSix-month-old healthy New Zealand rabbits were randomly divided (equal between genders) into normal control group, model group, and acupotomy group. We selected immobilized left knee joints of rabbits for KOA models. We started treating acupotomy group after modeling once a week and kept3weeks. We observed the pathology of the joint cartilage and synovium on the whole, the pathology of the joint cartilage through optical microscope and electron microscope. Tested the tension, creep and stress relaxation data of medial collateral ligament, lateral collateral ligament and patellar ligament by Bose Electro Force3300protracted test machine. Result1Behavioral alternations:Lequesne MG Score points of model group and acupotomy group before treatment, after treatment and the difference between them had statistically signigicant (P<0.05). Acupotomy can effectively improve arthralgia, Activity, swelling and gait of joint in KOA of rabbits.2General observation:Articular cartilage of normal control group did not change significantly. Articular cartilage of model group obviously lost luster, became pale and opaque. Crack even defect could be seen. Joint edge had fibrous adhesions. Synovium had hyperplasia severely. Synovia significantly increased and showed bubbles and turbidity. Part of the joints had formation of osteophyte. Articular cartilage of acupotomy group was light white. Some visible crack could be seen. There was mild synovium hyperplasia and synovia slightly increased than normal group. Through statistics analysis, acupotomy group and model group has an extremely significant difference (P<0.01) according to Peng Tai-Ping histopathological classification. Acupotomy could improve better for articular cartilage, synovium, joint capsule, and joint of the liquid than the model.3Optical microscope observation:Cartilages of normal control group were normal. Cartilages of model group were not smooth. There were a little Chondrocytes in the superficial zone. Chondrocytes were arranged irregularly and abnormality. Defect arrived to tidemark sometimes. Sometimes the tidemark was unclear or double tidemark could be seen. Tidemark was clear in acupotomy group and chondrocytes were arranged irregularly. Cartilages were smooth, pannus couldn't be seen. Through the statistical analysis, three groups have extremely significant difference (p<0.01) in accordance with Mankin classification. There were significant difference between acupotomy group and normal control group (P<0.01). Acupotomy can effectively reduce the cartilage damage.4Electron microscope observation:The nucleus of chondrocyte in normal contral group was ovoid, surface of cell had many slender apophysis, and the body and membrane of the cell were integrity. There were rich organelles in the cytoplasm, chromatin was well-distributed, collagen fiber lined up in order. The nucleus of chondrocyte in model group became pyknotic obviously, part of them were dissolved and necrosis. The appearance is irregular, nuclear membrane was not obvious, and microvilli and protuberant of the surface reduced. Organelles of cytoplasm condensed in high electronic density, and were not easy to distinguish. There were several lipid drops in cell. There were rich organelles in the cytoplasm of acupotomy group. The shape of nuclear was normal. Chromatin was well-distributed. Microvilli and protuberant of the surface disappeared almost. There are many rough endoplasmic reticulums and vacuoles in the cytoplasm. Part of collagenous fiber was fracture around cells.5The result of ligamentous mechanics:Through testing tensile mechanics of the three groups we found that the maximum displacement, the maximum stress, modulus of elasticity and maximum strain in the three groups are statistically significant. Multiple comparison, model group and the normal control group had significant differences (P<0.05, P<0.0\), acupotomy group and the model group also had significant differences (P<0.05, P<0.01). Acupotomy obviously improve tensile mechanical characteristics of ligament. By comparing creep and stress relaxation curves of he three groups, we found that curves of model group and normal group split obviously, and the MCL curves of the acupotomy group and model group were almost coincidence. The LCL and patellar ligament curves of the acupotomy group and model group were split obviously. Creep rate and relaxation rate of the three ligaments also has a significant difference (P<0.05, P<0.01). Overall, acupotomy had good improving function for the creep and stress relaxation of ligaments.ConclusionWe think mechanics unbalance of joint is an important element of KOA in the pathogenesis, and abnormal changes of ligamentous mechanics may be one of reason or result of joint force unbalance, so it is the effective way of the KOA intervention that adjusting the force unbalance of the ligaments in order to alter the mechanics unbalance. Treating KOA by acupotomy properly depends on relieving the abnormal increased tension ligament. Once ligament get to loose solution, the vicious cycle and pathogenesis of KOA will be broken. At the same time, the improvement of the joint mechanics balance eventually led to the articular cartilage to repair itself through the mechanics signal transduction of the cartilage cells which can regulate cell gene expression in cells.