the Safety and Efficacy Evaluation of Chondron Compared With Mircrofracture of Knee

It is an open clinical trial. Among the patients who received autologous cartilage cell graft using CHONDRON (autologous cartilage cells) in the past (investigational group) or microfracture (control group), the subjects who agreed to participate in the trial voluntarily will undergo the screening process that assesses the suitability of the subjects to the clinical trial and participate in the clinical trial. During the clinical trial period, the subjects should follow the instruction of clinician in charge. Hospital visit is total 2 times* regularly. At the visit, to evaluate the efficacy according to the protocol, the subject will be examined by clinicians, MRI test, and X-ray. If the selection time and the visit time are same, hospital visit will be one time*.

Inclusion criteria

• 1. Patients who underwent autologous chondrocyte implantation using CHONDRON (autologous cultured chondrocyte) or patients underwent microfracture more than 2 years ago.

• Patients who meet the above criteria 1, the patient or a guardian agreed to participate in the clinical trial, and signed a written agreement form

Exclusion criteria

• 1. Patients with psychological disease or other patients who are determined to be unsuitable to this clinical trial by the investigators conducting the clinical trial.

• Patients who underwent autologous chondrocyte implantation applying CHONDRON (autologous cultured chondrocyte) or microfracture, and the lesion was treated with other procedures subsequently.