Objective:To compare the therapeutic effect of lateral position and half lithotomy position in Asian proximal femur intramedullary nail antirotation system (PFNA-II) for treating the elderly patients with femoral intertrochanteric fractures.Methods:A retrospective case control study was made on 141 patients with femoral intertrochanteric fractures admitted to Jiangjin Central Hospital from January 2016 to September 2017, including 54 males and 87 females, aged 65-99 years (mean, 80.4 years). According to AO classification, there were 42 patients with type A1 fractures, 88 with type A2 and 11 with type A3. Of all, 74 patients were stabilized by PFNA-II internal fixation in lateral position (lateral position group) and 67 patients by PFNA-II internal fixation in half lithotomy position (half lithotomy position group). The postural placement time, total incision length, operative time, intraoperative blood loss, fluoroscopy frequency, tip-apex distance, reduction quality, fracture healing time, postoperative complications and Harris hip function at 12 months after surgery were compared between the two groups.Results:All patients were followed up for 12-18 months (mean, 12.5 months), except that 13 patients were lost after 9 months, an average of 12.5 months. There were no statistically significant differences in postural placement time, operative time, fracture healing time, and Harris hip score between the two groups ( P>0.05). While significant differences were seen between lateral position group and half lithotomy position group regarding the incision length [(6.5±1.3)cm vs. (7.5±1.5)cm], intraoperative blood loss [(84.3±3.1)ml vs. (90.4±3.9)ml], fluoroscopy frequency [(13.1±1.9)times vs. (11.2±1.2)times], tip-apex distance [(20. 6±2.2)mm vs. (24.4±1.8)mm], good rate of reduction quality (80% vs. 85%) and implant related complications (5% vs. 2%) ( P<0.05 or 0.01). Conclusion:For treatment of elderly patients with intertrochanteric fractures, compared to the lateral position, the half lithotomy position in PFNA-II internal fixation can reduce frequency of fluoroscopy, improve quality of fracture reduction and reduce implant-related complications.

Objective:To study and design one kind of flash radiotherapy(Flash-RT)equipment with ultra-high dose rate,which can be used in the mechanism research of Flash-RT with ultra-high dose rate.Methods:Based on the technique roadmap of high-power petal accelerator,the Flash-RT equipment can realize the requirement of Flash-RT for ultra-high dose rate and multiple irradiation angles.The corresponding design and research work were carried out on the basis of the overall design of the equipment,the main components and characteristics,the dynamics design of beam,the construction of movable and preliminary experimental platform,etc.Result:The dose rate of the designed equipment can reach to 100 Gy/s at a distance of 0.8 meters from the target point,which is easy to realize the radiotherapy method with multi angles.Conclusion:The designed X-ray equipment based on the technique roadmap of high-power petal accelerator can realize the research for the mechanism of medical Flash-RT equipment with ultra-high dose rate.

The protection effect of flash-radiotherapy(Flash-RT)with super-high dose on normal tissue has obtained wide attention in therapeutic radiology since it was found in 2014 year.The increasing research demand of Flash-RT with super-high dose-rate proposed new challenge for the existing radiotherapy equipment.Based on the demands of FLASH-RT research and clinical application,this review analyzed the proposed new requirement of Flash-RT for equipment,and introduce current scientific facilities with the experimental ability of X-ray FLASH-RT,as well as the situation of the specialized FLASH-RT equipment which were developing.The research of Flash-RT mechanism need the existing equipment with high-energy X-ray source develop toward high power,while the clinical application of Flash-RT demand these transient high-power devices should possess a series of radiotherapy techniques such as multi angle irradiation,conformal radiotherapy and others.Currently,China's X-ray FLASH-RT research is at the forefront of the world,which is expected to achieve the first breakthrough of high-end medical equipment in the X-ray Flash RT field.