A Trial to Evaluate the Combination Efficacy of Artificial Dermis and Growth Factor in Chronic Wounds Ulcer

Inclusion Criteria:

1. Patients diagnosed as chronic wounds ulcer;
2. The affected limb has sufficient blood perfusion. The ankle brachial index was 0.65-1.3, or the partial pressure of oxygen was more than 40 mmHg, or Doppler ultrasound showed enough blood flow.
3. After debridement, the distance between the wound and the edge of other ulcers was >2cm.
4. After debridement, the area of exposed bone or tendon was >4cm2.
5. The wound was completely debridement without obvious necrosis, infection control or osteomyelitis control.
6. The duration of ulcer wound was at least 30 days.
7. Sign the informed consent voluntarily.

Exclusion Criteria:

1. Poor control of diabetes (fasting blood glucose ≥ 8.0mmol/l, HbA1c ≥ 12%);
2. The researchers think that there are factors affecting wound healing, such as the use of corticosteroids, immunosuppressants and other drugs, chemotherapy or radiotherapy within one year.
3. To receive or plan to receive drugs or treatment, the researchers believe that these drugs or treatment will interfere with or affect the speed and quality of wound healing;
4. Unstable Charcot's foot or Charcot's joint disease with bone protrusion;
5. Patients with severe lymphedema, coagulation disorders, autoimmune diseases, cardiovascular and cerebrovascular diseases, and severe hepatopulmonary and renal diseases;
6. Those who have received hyperbaric oxygen treatment within 5 days before enrollment, or who have received or plan to receive growth factor, tissue-engineered skin or other skin substitutes treatment within 30 days;
7. Those who have participated in or are participating in other clinical studies within 30 days before screening;
8. Pregnant, or lactating women;
9. Poor general condition or other conditions not suitable for the use of double-layer artificial leather repair materials;
10. Be allergic to collagen or chondroitin sulfate;
11. Other cases that researchers think are not suitable for the participation.