Stem cells produced from bone marrow or fatty tissue are sent to the affected knee by injection, which is expected to heal. In the event of damage to the cartilage of the knee, the action of the target cells is ensured by means of a carrier dependent on hyaluronic acid or collagen, so the stem cells are able to work only in the damaged area without spreading above the knee. Since a stem cell is a person’s own cells, tissues are meant for healing and regeneration.