Saving the ligament: a trial tests whether repairing a torn ACL beats replacing it

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Patients with anterior cruciate ligament tear clearly identified by imaging or intraoperative microscope, Sherman grade I, II; planned surgery within 3 weeks after injury 2. Basic reading and writing skills, and barrier-free communication 3. A smartphone, can use WeChat or be able to learn 4. Patients give informed consent, and sign the informed consent form, and the process must meet the requirements of GCP Exclusion Criteria: 1. Combined with other knee joint injuries (posterior cruciate ligament injury, patellar dislocation, osteoarthritis, etc.) 2. Suffering from systemic immune diseases; 3. Existing other knee joint diseases or inflammatory diseases, including osteoarthritis, cervical spine disease, rheumatoid arthritis, fibromyalgia, polymyalgia rheumatica, etc. 4. Patients who have received local hormone injection within 3 months; 5. Those who have participated in clinical trials or are undergoing other clinical trials within 3 months before screening 6. Those who have serious primary cardiovascular disease, lung disease, endocrine and metabolic disease or serious diseases that affect their survival, such as tumor or AIDS, the researchers believe that they are not suitable for selection 7. Patients with severe liver disease, kidney disease, and hematological disease, such as renal function exceeding the upper limit of the normal value, and liver function exceeding 2 times the upper limit of the normal value; 8. Suffering from viral hepatitis, infectious diseases, severe abnormal blood coagulation mechanism and other Diseases that the researchers consider inappropriate for surgery 9. Women who are pregnant or breastfeeding, or who plan to become pregnant during the follow-up period, those who have a positive urine human chorionic gonadotropin test result before sampling; menstruating women should wait until the end of menstruation before surgery; 10. Severe neurological and mental disorders Disease patients; 11. Suspected or actual history of alcohol and drug abuse.