Objective To find a new culture system to induce proliferation and osteodifferentiation of marrow stromal cells (MSCs) in vitro for bone tissueeng ineering． Methods There were four groups in this experiment to study effects of Passage 3 osteoblasts derived from the rat cranium and the osteogenic inductor (1 nmol/L dexamethasone，10 mmol/L beta-glycero-phosphate，50 μg/ml retin oic acid) on growth of MSCs isolated from the rat femur and the tibia． MSCs were cultured in the DMEM medium (the c ontrol group) and in the osteoinductive culture medium (the inductor group)；fur thermore, MSCs were co-cultured with the osteoblasts in the DMEM medium (the osteoblast group) and in the osteoinductive culture medium (the combined treatment group)．The cells in the four groups were counted every 2 days for 8 days and alkaline phosphatase (ALP) activity of MSCs at 10 days of cultivation was measured．The MRNA expression of osteocalcin (OC) of MSCs at 2 weeks was assayed with the reverse transcript polymase chain reaction (RT-PCR)． Results There were more cells in the osteoblast group than in the control group(31.73±3.31×104 V S. 24.33±3.04×104, Plt;0.05), but there were fewer cells in the inductor gro up(16.23±2.44×104, Plt;0.05). There was no significant difference in th e cell number between the combined treatment group (21.54±2.29×104) and th e control group（Pgt;0.05）．The ALP activity was higher in the combined trea tment group （2.01±0.56 U）than in the control group (1.27±0.43 U), in the inductor group（1.27±0.43 U）, and in the osteoblast group （0.77±0.19 U）.The osteocalcin mRNA was expressed in the three treat ment groups but was not expressed in the control group. The significantly higher leve l of the osteocalcin mRNA was expressed in the inductor group（0.783±0.094）and in the combined treatment group（0.814±0.071）than in the osteoblast group（0.302±0.026） (Plt;0.05). Conclusion The combined use of t he osteoblast and the inductor can induce marrow stromal cells. Their combined u se does not affect the normal proliferation but can obviously promote the osteodifferentiation of marrow stromal cells. This combined use can become a new culture system of the seed cells for bone tissue engineering．
Objective To assess the effectiveness of suture button fixation Latarjet procedure under total arthroscopy for anterior shoulder instability with severe bone defects. MethodsThe clinical data of 15 patients with severe bone defects and anterior shoulder instability treated with suture button fixation Latarjet procedure under total arthroscopy between June 2020 and February 2023 was retrospectively analyzed, including 11 males and 4 females, with an average age of 31.1 years (range, 20-54 years). Three-dimensional CT showed that the average glenoid bone defect was 24.4% (range, 16.3%-35.2%). The average number of shoulder dislocation was 4.2 times (range, 3-8 times). The disease duration ranged from 6 to 21 months with an average of 10.6 months. The operation time and intraoperative blood loss were recorded. The pain relief was evaluated by visual analogue scale (VAS) score, and the functional recovery of shoulder joint was evaluated by Rowe score, Walch-Duplay score, and American Association for Shoulder and Elbow Surgery (ASES) score before and after operation. The range of motion (ROM) of the shoulder joint was assessed, including active flexion, lateral external rotation, abduction 90° external rotation, and internal rotation. Three-dimensional CT was performed at 6 months after operation and at last follow-up to observe the absorption of bone graft, the position of bone graft and glenoid, and the healing of bone graft. Results The operation was successfully completed in all patients. The operation time was 85-195 minutes, with an average of 123.0 minutes. The intraoperative blood loss was 20-75 mL, with an average of 26.5 mL. All patients were followed up 13-32 months, with an average of 18.7 months. During the follow-up, there was no serious complication such as shoulder joint infection, joint stiffness, or vascular and nerve injury. One patient had partial absorption of the transplanted bone and bone nonunion at 3 months after operation, but the pain of the shoulder joint relieved at last follow-up, and no redislocation of the shoulder joint occurred; no obvious bone fracture or dislocation of the shoulder joint was found in the other patients. Bone union was achieved at 6 months during follow-up. At last follow-up, the VAS score, Rowe score, Walch-Duplay score, and ASES score significantly improved when compared with those before operation (P<0.05), while the ROM of active flexion, lateral external rotation, abduction 90° external rotation, and internal rotation of the shoulder joint was not significantly different from those before operation (P>0.05).ConclusionSuture button fixation Latarjet procedure under total arthroscopy can improve shoulder joint function in patients with severe anterior shoulder instability caused by bone defects, and imaging also indicates satisfactory placement of transplanted bone blocks.