UCMSC Transplantation in the Treatment of Cartilage Damage

Inclusion Criteria: * Patients whose lesion (single joint) should be in the range of 2 cm\^2-8 cm\^2. * Patients with pain in affected joint of 60 mm- 100 mm VAS (visual analogue scale) * Patients with articular swelling, tenderness and active range of motion of Grade 2 or below * Patients with knee joint cartilage defect or injury of ICRS (International Cartilage Repair Society) Grade 4 confirmed by arthroscopy (At screening, patients diagnosed as such with an MRI may be included) * Patients who needs invasive interventions of arthroplasty due to no response from existing pain medication * Patients voluntarily agreed to participate in the study and signed informed consent Exclusion Criteria: * Patients with autoimmune diseases or medical history * Patients with infections requiring injection of antibiotics * Patients with severe internal diseases * Patients who are currently pregnant or lactation * Patients who had participated in any other clinical trials within the past four weeks * Patients who had been administered with immunosuppressants within the past four weeks * Patients whom the principal investigator considers inappropriate for the clinical trial due to any other reasons than those listed above