This study was to evaluate the safety and efficacy of Mesenchymal Stem Cells (MSCs) from umbilical cord in the treatment of 7 knee OA patients by assessing unexplained local and systemic symptoms or death before and at 1, 2, 3, 6 months after the injection.

This is a single group assignment study with a total of 9 knee osteoarthritis patients participants. All of the patients will receive the anticular injection with MSCs from umbilical cord and unexplained local and systemic symptoms or death before the end of following-up will be assessed to evaluate the safety and efficacy of mesenchymal stem cells from umbilical cord.

Inclusion Criteria:

① K / L score of 2-3; ② chronic knee pain; ③ no local or systemic infection; ④ without obvious contraindication of the joint puncture from hematology and biochemical tests; ⑤ informed consent. -

Exclusion Criteria:

① older than 75 years old or less than 18 years old, or without full capacity for civil conduct; ② HIV, hepatitis virus or syphilis virus infection or their serology is positive; ③ BMI index is greater than 30; ④ congenital or acquired knee deformity; ⑤ pregnant or lactating women; ⑥ tumor patients; ⑦ immunodeficiency patients; ⑧ intra-articular drug injection history within 3 months; ⑨ participating in other clinical trials; ⑩ other patients who researchers believe are not eligible for inclusion such as suffering from other concomitant diseases. -