Abstract: Objective To investigate the effect of knee joint reconstruction with anterior cruciate ligament（ACL）reconstruction with knee tendon autograft and its influence on knee joint function.Methods 80 cases of patients with knee micro fracture were selected.The patients were divided into the observation group and the traditional operation group（40 cases of each）according to the operation mode.The observation group was treated with Reconstruction of anterior cruciate ligament with autogenous tendon under knee arthroscopy.The general situation of the two groups of patients was observed，and the difference of knee joint physical signs，knee joint function between the two groups before and after operation were compared.Results There was no difference in the operation time between the observation group and the traditional operation group[（75.32±5.43）min vs（75.36±5.12）min，P＞0.05]，and the amount of bleeding in the observation group[（33.26±3.41）ml] was significantly lower than that in the traditional operation group[（52.42±6.18）ml](P＜0.05）.There was no difference in clinical signs between the two groups.The 3 months after the operation，the knee tenderness，joint mobility and joint swelling score of the observation group were lower than those of the traditional operation group；The knee function of the two groups had no difference before operation.After 3 months，the scores of knee joint stability，tenderness，activity and muscle strength of the observation group were higher than those of the traditional operation group.Conclusion Reconstruction of anterior cruciate ligament with autogenous tendon under knee arthroscopy is a better treatment for knee joint micro fracture，and can improve the knee function of patients，and has good application value.

Key words: arthroscopy, knee joint injury, swelling