The Study On Meniscus Allograft Transplantation In Dogs

Objective: The meniscus plays a key role in the function of the knee joint. Loss of meniscus frequently leads to osteoarthritis and knee joint dysfunction. In this study, meniscus allograft transplantation was evaluated in dogs to lay a foundation for further research on meniscus injury and provide a reference for meniscus injury treatment in humans.Methods: Sixteen local hybrid dogs were divided into whole meniscus transplantation group, half meniscus transplantation group, not meniscus transplantation group, normal control group, four dogs for each group. Whole meniscus transplantation group: whole medial meniscus of the right knee was replaced by allogeneic meniscus. Half meniscus transplantation group: the medial meniscus anterior of left knee was replaced by allogeneic meniscus. Not meniscus transplantation group: whole medial meniscus of the right knee and anterior part of the medial meniscus of left knee were resected, which served as donor meniscus. Normal control group: normal dogs without operation. The sixth weeks after surgery, five aspects were used to evaluate each group, namely: gross observation and Lysholm scores of the knee joint function, joint fluid examination, necropsy, histological observation, the Mankin’s scores of tibial plateau cartilage.Results: Five weeks after surgery, all transplanted dogs tended to stand, walk and climb stairs as normal, while the control dogs without meniscus walked with a slight limp and climbed stairs difficultly. The sixth week after surgery, Lysholm scores of knee joint function showed that, the whole meniscus transplantation group and the half meniscus transplantation group had no significant difference from the normal control group, however, there was a significant difference between the not transplantation group and the normal control group. No infection was detected in the joint fluid examination. The joint fluid constituents of the transplanted group were basically consistent with the control group, but inflammatory cells were increased in the not transplanted group. Necropsy showed that the donor meniscus grew well in the receptor without a change in position. The donor meniscus and the capsular healed well, and the surface of the donor meniscus was covered with a smooth synovium-like tissue in the whole transplantation group. The color and elasticity of donor meniscus were similar to normal meniscus in the half meniscus transplantation group. A little tissue grew into the edge of the tibial plateau in the not transplanted group, the articular cartilage abraded seriously and the surface of the femoral condyle was rough. Histological observation revealed that, the donor meniscus and the receptor’s joint capsule as well as the donor meniscus and the receptor’s reserved meniscus connected well, and the tissue was in a good condition in the junction. Observation of the tibial plateau cartilage showed that, there was a clear boundary between each layer, but curve tidemark was detected in the whole transplantation group. The partial transplantation group was similar to the normal articular cartilage. For the negative control group, the tibial surface of the plateau cartilage had irregular fissures, cells diffused and the tidemark was in a mess. Mankin’s scores of the tibial plateau cartilage showed that, the whole meniscus transplantation group and the half meniscus transplantation group had no significant difference from the normal control group, while the not transplantation group had significant difference from the normal control group.Conclusions: The surgical technique of canine meniscus transplantation was found to be feasible. Meniscus allograft transplantation could both protect the tibial cartilage and improve the knee joint function effectively, which made it a good way to treat canine meniscus injury.