BACKGROUND:The AO12-C type middle-proximal humeral fractures are usually caused by high-energy injuries,accompanied by comminuted fractures and a large number of butterfly-shaped bone fragments.These fractures are difficult to achieve good reduction and effective fixation.With the increasing understanding of the biological characteristics of bone and soft tissue,surgical treatment is gradually shifting towards minimally invasive steel plates and intramedullary nail fixation.However,there has been no consensus on which is the best surgical technique for treating humeral fractures in minimal invasive plate osteosynthesis and intramedullary nail.OBJECTIVE:To compare the clinical effect of minimal invasive plate osteosynthesis and intramedullary nail for treating AO12-C type middle-proximal humeral fractures.METHODS:A retrospective analysis was performed in 36 patients with AO12-C type middle-proximal humeral fracture who met the inclusion criteria admitted to the Guizhou Hospital of Beijing Jishuitan Hospital from January 2020 to December 2022.All patients were assigned to minimal invasive plate osteosynthesis group(18 cases)and intramedullary nail group(18 cases)according to the surgical treatment plan.The minimal invasive plate osteosynthesis group received minimally invasive plate osteosynthesis based on preoperative planning assisted by 3D printing,while the intramedullary nail group received intramedullary nail internal fixation.Operation time,intraoperative blood loss,hospital stay,and fracture healing time were compared between the two groups.Visual analog scale score at 1,3,and 6 months after surgery,shoulder joint function,Constant-Murley score,Quick Disabilities of the Arm,Shoulder and Hand(QuickDASH)score,and complications of the shoulder joint at the last follow-up were compared between the two groups.RESULTS AND CONCLUSION:(1)All patients were followed-up for average(15.56±4.05)months,and no difference was observed in hospital stay and fracture healing time between the two groups(P＞0.05).The minimal invasive plate osteosynthesis group had shorter operation time compared to the intramedullary nail group(P＜0.05).The intramedullary nail group had less intraoperative blood loss between the two groups of patients(P＜0.05).(2)In the intramedullary nail group,at 1 and 3 months after operation,the visual analog scale score was significantly lower than the minimal invasive plate osteosynthesis group(P＜0.05).No difference was observed in the visual analog scale in long-term follow-up,shoulder joint function,Constant-Murley score,Quick Disabilities of the Arm,Shoulder and Hand(QuickDASH)score at the last follow-up between the two groups(P＞0.05).(3)No complications such as nonunion or wound infection occurred in either group.Two cases of radial nerve palsy occurred in minimal invasive plate osteosynthesis group,both of which recovered within 3 months.The intramedullary nail group had 1 case of rotator cuff injury.There was no significant difference in the rate of complications between the two groups(P＞0.05).(4)To conclude,minimal invasive plate osteosynthesis and intramedullary nail can achieve good clinical efficacy in the treatment of AO12-C type middle-proximal humeral fractures,effectively improving shoulder joint function in patients.However,minimal invasive plate osteosynthesis exhibits obvious advantages in shorter surgical time with the assistance of 3D printing,which is a valuable,effective,and safe method for treating AO12-C type middle-proximal humeral fractures.

BACKGROUND:The AO12-C type middle-proximal humeral fractures are usually caused by high-energy injuries,accompanied by comminuted fractures and a large number of butterfly-shaped bone fragments.These fractures are difficult to achieve good reduction and effective fixation.With the increasing understanding of the biological characteristics of bone and soft tissue,surgical treatment is gradually shifting towards minimally invasive steel plates and intramedullary nail fixation.However,there has been no consensus on which is the best surgical technique for treating humeral fractures in minimal invasive plate osteosynthesis and intramedullary nail.OBJECTIVE:To compare the clinical effect of minimal invasive plate osteosynthesis and intramedullary nail for treating AO12-C type middle-proximal humeral fractures.METHODS:A retrospective analysis was performed in 36 patients with AO12-C type middle-proximal humeral fracture who met the inclusion criteria admitted to the Guizhou Hospital of Beijing Jishuitan Hospital from January 2020 to December 2022.All patients were assigned to minimal invasive plate osteosynthesis group(18 cases)and intramedullary nail group(18 cases)according to the surgical treatment plan.The minimal invasive plate osteosynthesis group received minimally invasive plate osteosynthesis based on preoperative planning assisted by 3D printing,while the intramedullary nail group received intramedullary nail internal fixation.Operation time,intraoperative blood loss,hospital stay,and fracture healing time were compared between the two groups.Visual analog scale score at 1,3,and 6 months after surgery,shoulder joint function,Constant-Murley score,Quick Disabilities of the Arm,Shoulder and Hand(QuickDASH)score,and complications of the shoulder joint at the last follow-up were compared between the two groups.RESULTS AND CONCLUSION:(1)All patients were followed-up for average(15.56±4.05)months,and no difference was observed in hospital stay and fracture healing time between the two groups(P＞0.05).The minimal invasive plate osteosynthesis group had shorter operation time compared to the intramedullary nail group(P＜0.05).The intramedullary nail group had less intraoperative blood loss between the two groups of patients(P＜0.05).(2)In the intramedullary nail group,at 1 and 3 months after operation,the visual analog scale score was significantly lower than the minimal invasive plate osteosynthesis group(P＜0.05).No difference was observed in the visual analog scale in long-term follow-up,shoulder joint function,Constant-Murley score,Quick Disabilities of the Arm,Shoulder and Hand(QuickDASH)score at the last follow-up between the two groups(P＞0.05).(3)No complications such as nonunion or wound infection occurred in either group.Two cases of radial nerve palsy occurred in minimal invasive plate osteosynthesis group,both of which recovered within 3 months.The intramedullary nail group had 1 case of rotator cuff injury.There was no significant difference in the rate of complications between the two groups(P＞0.05).(4)To conclude,minimal invasive plate osteosynthesis and intramedullary nail can achieve good clinical efficacy in the treatment of AO12-C type middle-proximal humeral fractures,effectively improving shoulder joint function in patients.However,minimal invasive plate osteosynthesis exhibits obvious advantages in shorter surgical time with the assistance of 3D printing,which is a valuable,effective,and safe method for treating AO12-C type middle-proximal humeral fractures.

BACKGROUND:Using degradable materials for bone tissue engineering to treat bone defects is the best choice at present. How to ensure adequate vascularization in materials in order to meet the need of blood supply and an exchange of nutrients for seed cells in the process of bone regeneration is becoming a critical problem reversed from basic research to clinical application.
OBJECTIVE:To review the biodegradable materials for bone tissue engineering and the ways to promote vascularization in materials.
METHODS:A computer-based search of PubMed and PMC databases was performed by the first author for the literature about biodegradable materials for bone tissue engineering and their vascularization published from 1993 to 2013. The key words were“degradable materials, bone tissue engineering, angiogenesis, vasculogenesis, osteogenesis”in English.
RESULTS AND CONCLUSION:The commonly used biodegradable materials for bone tissue engineering include synthetic polymer materials, magnesium al oy, bioactive glass ceramics, calcium phosphate ceramics and composites. We can promote the vascularization of tissue-engineered bone by the fol owing aspects:scaffold fabrication, growth factors, the application of endothelial progenitor cells, cells co-culture and microsurgical techniques. Although the research on the vascularization of tissue-engineered bone has made a great progress, there is stil a lot of shortcomings. We believe that, with the development of mechanism of angiogenesis, the vascularized tissue-engineered bone wil have a promising prospect because of improving the structure and properties of materials, promoting the ability of release-control ed growth factors and their synergies, optimizing the selection and mixed culture of seed cells and improving the microsurgical techniques.