Efficacy of Allogeneic UCMSCs for Treating Large Defects Knee Injury

Inclusion Criteria: 1. Men and women aged between 18 and 65 years. 2. Patients diagnosed to have ICRS Grade 3 or 4 cartilage lesions based on the MRI scans of the affected knee. 3. Presence of knee swelling, pain, stiffness, or knee mechanical symptoms resulting from cartilage lesions. 4. All subjects must also satisfy at least 1 of the following inclusion criteria. * Isolated knee articular cartilage lesion (single lesion) estimated to be ≥1.0 cm2 as demonstrated on MRI scanning. * Multiple knee articular cartilage lesions (multiple lesions) with at least 1 lesion estimated to be ≥1.0 cm2 as demonstrated on MRI scanning. * Bipolar cartilage defects demonstrated on MRI scanning with at least 1 articular surface lesion to be ≥1.0 cm2. * One or more cartilage defects involving the patella-femoral joint as demonstrated on MRI scanning with at least 1 lesion ≥1.0 cm2. * One or more cartilage defects involving the tibio-femoral joint as demonstrated on MRI scanning with at least 1 lesion ≥1.0 cm2. * Previously failed cartilage repair procedures (i.e., microfracture, osteochondral autograft transplantation surgery (OATS), ACI) within 6 months. Exclusion Criteria: 1. Preoperative flexion deformity greater than 10 degrees. 2. Significant cognitive impairment, non-ambulatory status or lower extremities amputation other than toes, serious illness or medication affecting operative risk or wound healing (e.g., steroid intake, anticoagulation). 3. Patient with high co-morbidity 4. Higher risk for postsurgical (e.g., bleeding disorder or taking anticoagulants except low-dose aspirin) or postsurgical infection (e.g., taking immune-suppressants, have a severe infection or a history of serious infection). 5. Significant peripheral vascular disease of the lower limbs as indicated by absent or substantially reduced dorsalis pedis or posterior tibial pulses. 6. Contraindications to sub-chondral drilling surgery. 7. Women who are pregnant or who are not able to use contraceptives 8. Known hypersensitivity (allergy) to hyaluronate or antibodies used for postsurgical prophylaxis. 9. Infections or skin disease affecting the area of the injection site or joint. 10. Intra-articular injections of hyaluronic acid in the target knee within the past 6 months before screening. 11. Intra-articular injections of corticosteroids in the target knee within the past 3 months before screening. 12. In the opinion of the investigators, the subjects have difficulty understanding or complying with the protocol procedures or requirements including follow up. 13. In the opinion of the investigators, the subject has any medical, psychiatric, or other condition for which the study would pose particular safety risks and/or unfavorably affect the risk-benefit balance of participation. 14. Presence of metallic implants, clips, or devices in the brain, eye, or spinal canal or implanted devices that are magnetically programmed that may affect the ability to perform MRI MOCART scoring. 15. Significant knee malalignment, varus or valgus deformity with more than 10 degrees, or instability associated with ligamentous knee injury.