Efficacy and Safety of Chondron (Autologus Chondrocyte) in Patients With Cartilage Defects in Their Ankle

Inclusion Criteria: * Male or female subjects aged 15 to 65 years * Patients with MRI-confirmed partial cartilage defects of the ankle (≤15 cm² single lesion, ≤20 cm² multiple lesions) * Patients who have undergone correction for malalignment, ligament instability, or bone defects (if applicable) * Patients with normal surrounding cartilage * Patients with ICRS Grade III or IV cartilage defects * Subjects who provide written informed consent Exclusion Criteria: * Hypersensitivity to bovine protein or gentamicin * Inflammatory or autoimmune arthritis (e.g., rheumatoid arthritis, gout) * Pregnant, breastfeeding, or planning pregnancy * Tumors or serious comorbid conditions * History of radiotherapy or chemotherapy within 2 years * Uncontrolled diabetes or diabetes with complications * Active infection requiring antibiotics * Current corticosteroid therapy * Patients with mental illness or other conditions deemed unsuitable for this study by the clinical trial manager