Bone Reconstruction With Autologous Bone Marrow Mesenchymal Stem Cells in Vitro to Repair Long Tubular Bone Defects

Inclusion Criteria:

1. Age: 18-55 years old, gender unrestricted;
2. Defective nonunion with bone loss exceeding 30% of the bone cross-section and a length of 2-3 cm;
3. Solitary bone cysts involving more than 50% of the bone cross-section.

Exclusion Criteria:

1. Combined with local tumors, tuberculosis, infections or other bone-healing affecting lesions;
2. Systemic diseases affecting bone healing such as osteofibrous dysplasia, osteogenesis imperfecta, bone dystrophic diseases, and metabolic bone disorders;
3. Moderate-to-severe osteoporosis (BMD: T-score \< -2.5);
4. Severe systemic conditions including systemic malnutrition, systemic infectious diseases, severe cardiopulmonary diseases, coagulation disorders, and major organ failure;
5. Complicated with severe brain trauma;
6. Heavy smoking, drug abuse, alcoholism, or other harmful addictions;
7. Psychiatric disorders or patients with menopausal symptoms;
8. Concurrent participation in other studies or recent completion (within 4 weeks) of other clinical trials;
9. Pregnancy, lactation, or planned pregnancy within one year after initial enrollment;
10. Psychological conditions impairing treatment compliance;
11. Congenital malformations of vital organs or other systems;
12. Nonunion caused by malignant tumor resection;
13. Refusal to accept tissue-engineered bone repair protocol.