BACKGROUND:The mechanical characteristics of intramedul ary and intramedul ary fixations for treating intertrochanteric fracture were hot research of finite element, but there was few comparative research on tension side and pressure side of proximal femur. In our study, we found that the distribution of the stress zone was important indication to researches on intertrochanteric fracture and internal fixation design. OBJECTIVE:To explore the effects of intramedul ary and extramedul ary fixations for treating intertrochanteric fracture on pressure side and tensile side of proximal femur. METHODS:CT scan and Mimics modeling of volunteer’s femur were conducted, and the model Evans type I intertrochanteric fracture was constructed and treated with proximal femoral nail antirotation and dynamic hip screw respectively. The stress condition of proximal femur in weight status was simulated. The Abaqus 6.13 was used for finite element analysis, and the tension side and pressure side of proximal femur in both fixations were also analyzed. RESULTS AND CONCLUSION:(1) The stresses of compressive side and tensile side in proximal femoral nail antirotation group were both less than that in dynamic hip screw group. The stress of proximal femur in proximal femoral nail antirotation group was more similar to that in physiological status. (2) These findings verified that for treating intertrochanteric fracture, intramedul ary fixation exerted better mechanical behavior than extramedul ary fixation. The protection of compressive side and tensile side of proximal femur had achieved by intramedul ary fixation.

Objective To explore the feasibility of visually assessment of angiogenesis in a murine model of subcutaneous matrigel plugs with ultrasound molecular imaging(UMI) using microbubbles(MB)targeted to endothelial αv-integrins. Methods Matrigel angiogenesis was created by subcutaneous implantation of FGF-2 enriched matrigel in 10 mice. On day 10, UMI of the matrigel was performed in all mice at 6 minutes after intravenous injection of either αv-integrin targeting microbubbles(MBα) or isotype control microbubbles(MBc) in random with 30 min interval,and the video intensity(Ⅵ) was measured. To further test the specificity of the signal coming from MBα,antibody against αv-integrin was injected 10 min before microbubbles injection. Following UMI,all matrigels were harvested for histological analysis. Results As expected,VI of the matrigel was significantly higher ( P ＜0.05) for MBα (20. 5 ± 3.3)U as compared with MBc (4. 8 ± 1.5)U. After blocking with antibody against αv-integrin,a great decrease was observed in the MBα group [VI (4.6 ± 1.2) U, P ＜0.05] while no significant difference was noted for MBc [VI (4. 9 ±1.5)U, P ＞ 0.05 ]. Neovessels within matrigel was positive for αv-integrin. Conclusions UMI with microbubbles targeted to αv-integrins can be effective and specific in evaluating the angiogenesis in a murine model of subcutaneous matrigel plugs.

【Objective】 To analyze the application value of transcutaneous electrical acupoint stimulation (TEAS) in treating blood donation-related vasovagal reaction (DRVR). 【Methods】 The donors, experienced DRVR in our No.1 and No.2 mobile blood donation trucks from January 2020 to November 2021, were selected as research subjects and divided into TEAS group and control group, according to different treatment methods.After the occurrence of DRVR, the control group adopted routine treatment methods, such as stoping phlebotomy immediately, laid flat on the back with the feet higher than the head, head tilted to one side, and loosing collar or tight clothes.In case of syncope, acupressure was given to Renzhong and Hegu, pulse and blood pressure were monitored, and blood donors were provided with proper amount of liquid after consciousness recovery.The TEAS group received extra TEAS treatment based on the above methods.According to the symptoms of DRVR, the two groups were sub-divided into non-syncope DRVR and syncope DRVR to observe the effect of different treatments. 【Results】 The total effective rate of TEAS in non-syncope DRVR(97.33%) and syncope DRVR group(97.06%) was higher than those of control group (vs 91.13% and 76.67%)(P<0.05). The changes of blood pressure and heart rate of blood donors before blood donation and after treatment with the two methods in the TEAS group were lower than those in the control group (systolic blood pressure change value 5.24±2.87 mmHg vs 7.42±3.44 mmHg, diastolic blood pressure change value 3.17±2.24 mmHg vs 3.67±2.51mmHg, heart rate change value 2.71±0.35 beats/min vs 3.46±0.49 beats/min), P<0.05. 【Conclusion】 TEAS has better effect than conventional treatments, especially for DRVR with syncope, and can quickly and effectively improve the syncope related symptoms and shorten the recovery time.Moreover, it is safe, non-invasive, simple economic and effective, which deserves application and popularization in mobile blood donation sites.

Objective:To investigate the clinical efficacy of satellite rod revision surgery via a combined anterior and posterior approach for rod fracture after posterior vertebral column resection (PVCR) in patients with severe thoracolumbar kyphosis.Methods:A retrospective case series study was conducted on the clinical data of 11 patients with rod fracture after PVCR for severe thoracolumbar kyphosis, who were treated in Henan Provincial People′s Hospital from January 2013 to January 2021. There were 6 males and 5 females, with the age range of 21-62 years [(35.4±13.0)years]. Among them, 4 patients had traumatic kyphosis, 4 presented congenital kyphosis and 3 showed tuberculous kyphosis. All the patients had obvious low back pain. According to the American Spinal Injury Association (ASIA) score, 2 patients were found with grade C, 2 with grade D and 7 with grade E. All the patients underwent revision surgery for internal fixation using satellite rod via a combined anterior and posterior approach. The operation time, intraoperative blood loss and postoperative hospital stay were recorded. The imaging parameters such as kyphosis Cobb angle, scoliosis Cobb angle, distance between C 7 plumb line and central sacral vertical line (C 7-CSVL), and distance between C 7 plumb line and sagittal vertical axis (SVA) were measured preoperatively, at 1 week postoperatively and at latest follow-up. At the same time, the visual analogue scale (VAS), Oswestry dysfunction index (ODI), and simplified Chinese version of the scoliosis research society-22 (SRS-22) questionnaire were used to evaluate the clinical efficacy. At the latest follow-up, the osteotomy fusion was evaluated by Suk criterion and ASIA score was used to evaluate the recovery of neurological function. The complications were also recorded for the patients. Results:All the patients were followed up for 24-84 months [(47.5±16.2)months]. The operation time was 100-220 minutes [(149.4±37.6)minutes], with the intraoperative blood loss of 150-350 ml [(246.3±64.6)ml] and the postoperative hospital stay of 5-8 days [(6.1±1.1)days]. The kyphosis Cobb angles [(18.5±3.2)° and (19.3±2.9)°] and the scoliosis Cobb angles [(11.8±2.2)°, (11.1±2.2)°] at 1 week post-operation and at the latest follow-up were all improved significantly compared with the preoperative ones [(60.4±6.3)°, (21.7±5.5)°] (all P<0.01), with the average correction rates being 69.4% and 45.6%, respectively, with no significant differences between 1 week post-operation and latest follow-up (all P>0.05). The C 7-CSVL was reduced from preoperative (21.2±4.3)mm to (15.7±2.4)mm at 1 week post-operation, and to (15.9±2.2)mm at the latest follow-up (all P<0.01). The SVA was improved from preoperative (51.0±6.8)mm to (16.6±3.6)mm at 1 week post-operation, and to (15.3±3.9)mm at the latest follow-up (all P<0.01). There were no significant differences in C 7-CSVL or SVA at 1 week post-operation or at the latest follow-up (all P>0.05). The VAS [(2.5±0.9)points, (1.9±0.9)points], ODI (20.1±5.4, 18.4±5.2) and SRS-22 [(83.4±5.8)points, (85.0±4.1)points] at 1 week post-operation and at the latest follow-up were significantly improved compared with the preoperative ones [(6.0±1.4)points, 57.2±8.7, (62.0±9.1)points] (all P<0.01), but no significant differences were found between 1 week post-operation and latest follow-up (all P>0.05). At the latest follow-up, the bone grafts achieved osseous fusion in all the patients, and the ASIA grade was improved from grade C to grade D in 2 patients and from grade D to grade E in 2 patients. No complications such as serious neurological or vascular injury occurred during perioperative period. No pseudoarthrosis formation, internal fixation loosening or fracture occurred during follow-up. Conclusion:Satellite rod revision surgery via a combined anterior and posterior approach for rod fracture after PVCR in patients with severe thoracolumbar kyphosis has the advantages of less trauma and faster convalescence, excellent results of deformity correction, significant pain relief, functional improvement, and fewer complications.