CHANGCHUN, Jan. 23 (Xinhua) -- Surgeons in northeast China's Jilin Province have successfully transplanted new cartilage on a patient's damaged knee joint, the first such surgery in Chinese mainland.

The surgery with a technique imported from Germany was performed on Jan. 19 by Professor Zhang Liheng, director of Sports Medicine Center, People's Hospital of Jilin Province. The patient is in stable condition and can leave hospital in a week.

Doctors extracted cells of the cartilage tissue from the patient and grew them outside the human body. The surgery was done after the cells grew into new cartilage tissue.

Hyaline cartilage is the tough, flexible tissue that serves as a cushion for bones at joints, preventing them from rubbing against each other during physical activities. When the tissue is damaged, normal movement of the joint can become limited, and patients will suffer from severe pain or even disability.

But the damage to cartilage is not readily repaired by the body. In the past, clinicians had no better treatment than substituting the tissue with other materials, and thus movement of the joint would not fully recover. "As time goes by, the joint cavity may narrow, or the cartilage may degenerate," said Zhang. "The damage may result in disability in the worst scenario."

Thanks to the latest regeneration technique, the cartilage can be repaired and the illnesses of the joint can be cured permanently, said Zhang. With microfracture surgery, patients can experience tinier cuts and less pain.

Zhang has been working with German researchers on the technique for years, and established the Sino-Europe Cartilage Transplantation Therapy Center in May, 2016. The surgery in Jilin marked the successful employment of the technique in clinical treatment in the Chinese mainland.

(All photos are provided to Xinhua)