Objective:To investigate the application value of computer-assisted preoperative planning (CAPP) in the treatment of AO/OTA type-C distal femoral fractures.Methods:A retrospective analysis was conducted on 150 patients with AO/OTA type-C distal femur fractures from January 2010 to December 2021 using the less invasive stabilization system-distal femur (LISS-DF). Patients were divided into a non-CAPP group and a CAPP group based on whether computer-assisted preoperative planning was utilized. The non-CAPP group included 81 patients (56 males, 25 females) with an age range of 39 to 67 years (mean 54.9±5.8 years), consisting of 22 type-C1 fractures, 35 type-C2 fractures, and 24 type-C3 fractures. The CAPP group comprised 69 patients (50 males, 19 females) with an age range of 45 to 63 years (mean 53.9±4.6 years), including 18 type-C1 fractures, 28 type-C2 fractures, and 23 type-C3 fractures. The study recorded the time of preoperative planning and compared the surgical duration, intraoperative blood loss, times of fluoroscopy intraoperatively, and hospital stay length between the two groups. At the last follow-up, knee function was evaluated using the Hospital for Special Surgery (HSS) knee score and pain was assessed using the visual analogue scale (VAS).Results:The preoperative planning time of CAPP was 22.5±3.4 min (range, 17-31 min). There were statistically significant differences between non-CAPP group and CAPP group in terms of surgical duration (non-CAPP, 110.9±7.7 min; CAPP, 94.4±6.3 min), intraoperative blood loss (non-CAPP, 299.3±34.2 ml; CAPP, 224.1±22.0 ml), times of fluoroscopy intraoperatively (non-CAPP, 11.3±3.1; CAPP, 6.7±2.2), and hospital stay length (non-CAPP, 12.8±3.2 d; CAPP, 6.4±1.9 d) ( P<0.001). All patients were followed up, with the CAPP group having a follow-up duration of 17.7±3.3 months and the non-CAPP group having 18.1±3.7 months. Both groups of patients achieved clinical healing of fractures. The healing time for fractures in the CAPP group and the non-CAPP group were 13.9±1.1 weeks and 14.0±1.3 weeks, respectively, with no statistically significant difference ( t=0.699, P=0.490). At the last follow-up, the average HSS score and VAS score of the patients in the CAPP group were 86.6±3.4 points and 0.9±0.4 points, which were both better than those of the non-CAPP group 79.2±5.1 points and 1.3±0.5 points ( P<0.001). No patients in either group experienced complications related to delayed fracture healing, nonunion, or internal fixation failure. Conclusion:When using LISS -DF steel plate to treat complex distal femoral fractures, CAPP can assist the operator in efficiently and accurately completing preoperative design. Compared with traditional preoperative planning, it can reduce surgical time, surgical trauma, and achieve more satisfactory postoperative outcomes.

Objective:To design a large-scale mobile emergency resuscitation unit based on 5G communication technology to improve the efficiency of prehospital transportation and treatment.Methods:The study was conducted in Hangzhou from November 2022 to September 2023. It's sorted out the application scenario requirements for prehospital first aid, transfer, and prehospital-intrahospital emergency linkage in carrying out the program design, single technology testing, onboard debugging, and integration debugging phases sequentially.Results:In September 2023, a large-scale 5G mobile emergency resuscitation unit was completed and delivered. The unit was converted from an electric bus and consists of five parts: (1) Vehicle appearance: the vehicle is 12.9 meters long, 2.3 meters wide and 2.6 meters high, with a single mileage of 200 kilometers; (2) The overall internal structure: the vehicle has one resuscitation bed and two stretcher positions. Additionally, there is a comprehensive operating table located at the front of the vehicle. The middle of the vehicle is equipped with a central digital control screen. (3) First aid materials and instruments: the vehicle's materials are modularly configured in accordance with the resuscitation, guardianship, surgery, inspection and testing, Communication modular configuration, equipped with a defibrillation monitor, transfer ventilator, extracorporeal membrane lung oxygenation and other critical care first aid and electrocardiogram, digital radiography, blood gas analyzer, chest pain 5 monitors and other inspection and testing equipment; (4) Vehicle communication and information systems: equipped with high-definition remote video interactive system, telemedicine terminal DP300 integrated system, a real-time panoramic experience system and centralized guardianship system; (5) Vehicle disinfection: a plasma disinfector installed on the top of the car can meet the hospital disinfection hygiene standardsⅡ class environmental management requirements.Conclusions:Incorporating 5G communication technology, the large-scale mobile emergency resuscitation unit is equipped with various advanced treatment equipment and remote consultation systems. It can accommodate the resuscitation needs of the most critically ill patients, offering substantial support for public emergency rescues. Further exploration of its potential is merited.

Objective:To analyze the application value of three-dimensional computed tomography (3-D CT) reconstruction technique in the evaluation of related predictive parameters of osteoporotic hip fractures.Methods:From February 2014 to March 2019, 106 patients with hip fracture who underwent dual-energy X-ray bone density test of T≤ -2.5 SD on the hip were analyzed retrospectively. There were 58 males and 48 females; Age 73.50±5.59 years old (range, 65-88 years old); Height 170.12±7.43 cm (range, 152-187 cm); Weight (69.26±11.85) kg (range, 37-94 kg); Body mass index 23.60±2.37 kg/m 2 (range, 18.3-28.9 kg/m 2); There were 32 cases of femoral neck fractures, 68 cases of intertrochanteric fractures and 6 cases of subtrochanteric fractures. Anatomic parameters of the hip were the cortical thickness index (CTI), hip axis length (HAL), and femoral offset (FO). The above-mentioned predictive parameters of the hip fractures were measured based on X-ray and 3-D CT reconstruction images. Comparison of the two methods were analyzed using paired t test, liner Pearson analysis, and Bland-Altman analysis. Pearson analysis was used to evaluate correlation between CTI, HAL, and FO and T value. Results:106 cases were compared and analyzed with the measured values of X-ray and 3-D CT reconstruction images according to the preset measurement scheme. The mean value of CTI measured by conventional X-ray measurement method was 0.31±0.05, and the mean value of CTI measured by 3-D CT reconstruction images was 0.31±0.05. The result was not statistically significant ( t=0.938, P=0.35). The mean values of HAL, FO measured by conventional X-ray measurement method were 123.35±12.74 mm, 43.99±2.81 mm, and the mean values of HAL, FO measured by 3-D CT reconstruction images were 121.11±14.51 mm, 40.73±3.11 mm. The results were statistically different ( t=2.578, 18.502; all P< 0.05). The Bland-Altman results showed that there was no difference in the consistency of the two measurement methods for CTI while the measurement results of HAL, FO were quite different. CTI and HAL showed strong correlations with the T scores respectively ( r=0.784, -0.748; P< 0.001). Conclusion:Based on 3-D CT reconstruction technique, accurate measurement of related predictive parameters of osteoporotic hip fractures can be realized, which provides theoretical basis for the evaluation of osteoporotic hip fractures in the elderly and the formulation of accurate rehabilitation treatment plan.

Objective:To explore the feasibility and effectiveness of the construction of urban unmanned aerial vehicle (UAV) blood distribution system, and to provide a novel way for the distribution of emergency blood.Methods:The study was completed in Hangzhou from April 2019 to January 2021, and the main participants were from the Second Affiliated Hospital of Zhejiang University School of Medicine, Zhejiang Province Blood Center and Hangzhou Fast Ant Network Technology Co., Ltd. Firstly, an unmanned aircraft delivery system was built for urban emergency blood and a special blood storage box for drones were developed. The drone was used to deliver blood products from Zhejiang Province Blood Center to Binjiang Campus, the Second Affiliated Hospital of Zhejiang University School of Medicine, and the following indicators were obtained: (1) flight time of the drone blood delivery; (2) real-time temperature of blood products during transportation; (3) Baidu map software was used to measure the blood delivery time of road traffic, which was compared with the flight time of the drone.Results:The urban drone blood delivery system consists of intelligent logistics drones, cryogenic blood storage tanks, unmanned logistics hub stations, and cloud-based operation control platforms. The drone route distance from Zhejiang Provincial Blood Center to Binjiang Campus, the Second Affiliated Hospital of Zhejiang University School of Medicine was 2.36±0.06 km, and the ground distance was 5.8 km, with 27 flights from April 12, 2019 to January 29, 2021, and the drone flight time was, shorter than the road travel time for a round trip [(6.37±0.35) min vs. (17.00±1.94) min]. At different time points of the day, UAV blood delivery could save 15.98-4.28 min, with an average saving of 10.62±1.87 min. Conclusions:Urban UAV blood delivery systems have the advantages of being fast, unaffected by ground traffic conditions, and can ensure the safety of blood products during transportation, and are worthy of further exploration.

Objective:To investigate the application value of three-dimensional morphological measurement in the treatment of displaced intra-articular calcaneal fractures in the elderly.Methods:A retrospective case series study was conducted to analyze the clinical data of 44 patients with displaced intra-articular calcaneal fractures admitted to East Hospital Affiliated to Tongji University from January 2015 to January 2018. There were 33 males and 11 females, aged 60-88 years (mean, 67.2 years). According to Sanders classification, 35 patients were with type II fractures and 9 with type III fractures. All patients were evaluated with digital technology and received open reduction and internal fixation. The operation time, intraoperative blood loss, intraoperative fluoroscopy frequency and complications were recorded. Three-dimensional morphological parameters of calcaneal fractures were compared before and at latest follow-up, including horizontal length of the calcaneus, height of the posterior articular facet, height and length of the anterior process, Gissane angle, and B?hler angle. The visual analogue scale (VAS) and American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot function score were also compared.Results:All patients were followed up for 12-30 months (mean, 17.1 months). There were 31 patients with posterior articular facet depression more than 2 mm, and 13 patients showed the back shift of the whole or part of posterior articular facet more than 3 mm and varying degree of fracture of the upper or lateral wall part of calcaneus body. The operative time was 55-105 minutes (mean, 85.1 minutes). The intraoperative blood loss was 30-130 ml (mean, 74.9 ml). The intraoperative fluoroscopy frequency was 5-8 times (mean, 6.5 times). During the operation, the internal fixation was not changed. Two patients suffered from skin incision infection after operation. At latest follow-up, the horizontal length of the calcaneus, height of the posterior articular facet, Gissane angle and B?hler angle were significantly improved from that before operation [(76.9±4.1)mm vs. (75.5±5.2)mm, (24.2±2.1)mm vs. (22.5±2.9)mm, (29.0±6.2)° vs. (18.3±5.5)°, (124.8±7.2)° vs. (107.6±8.5)°, respectively] ( P<0.01). No significance was found in the height and length of the anterior process ( P>0.05). At latest follow-up, the VAS and AOFAS ankle-hind foot function score were also significantly improved compared to preoperation [(1.1±0.9)points vs. (4.4±0.9)points, (86.4±6.2)points vs. (49.9±6.3)points, respectively] ( P<0.01). AOFAS ankle-hind foot function score was excellent in 13 patients, good in 26, fair in 5, with the excellent and good rate of 87%. Conclusion:Three-dimensional morphological measurement can fully evaluate the damage of calcaneal fractures and provide data reference for the preoperative planning of open reduction and internal fixation in the elderly, so as to restore the calcaneus structure, relieve pain and improve ankle function.

Objective: evaluate the efficacy of a single medial locking plate and lag screws based on computer-assisted pre-operation plan (CAPP) for the treatment of pilon fractures. Methods: Between 2013 and 2016, data of 27 patients with pilon fractures who were treated using a single medial locking and lag screws based on CAPP were retrospectively analyzed. All the cas-es were AO/OTA 43-C type pilon fractures. According to the Rüedi-Allgöwer classification, there were 5 cases of type Ⅱ and 22 cases of type Ⅲ. Among 27 patients, 19 patients had fibula fracture. CAPP was performed for all fractures, including simulated re-duction, virtual surgery, and implantation of internal fixation. The time of CAPP, intraoperative realization of preoperative plan, op-eration time, intraoperative blood loss, and pre- and post-operative range of motion of ankle were recorded. Functional outcomes at final follow up were assessed using American Orthopedic Foot and Ankle Society (AOFAS) ankle hindfoot scale, visual analogue scale (VAS). Results: The mean time of CAPP was 25.8 minutes (range, 14-30 minutes). The average operating time was 138.5 minutes. The average intraoperative blood loss was 225.9 ml. All the twenty-seven patients were followed up for an average period of 18.6 months. The average AOFAS score, VAS score at the final follow-up was 82.9, 2.7 points respectively, which was signifi-cantly improved compared with those before operation (t=-19.358, 7.720; all P< 0.001). Conclusion CAPP system is convenient and efficient, which can facilitate the treatment of type C pilon fractures with a single medial locking plate and lag screws. In addi-tion, satisfactory clinical outcomes can be obtained.

Objective To compare the efficacy of early and delayed removal of debridement implant for infection after internal fixation of tibial fracture.Methods A retrospective case control study was conducted on the clinical data of 27 patients with tibial fractures who received plate or screw internal fixation admitted to the East Hospital Affiliated to Tongji University from March 2005 to September 2016.There were 21 males and six females,aged 18-81 years [(41.6 ± 14.3)years].According to the treatment methods,the patients were divided into the delayed implant removal group (Group A,10 patients) and the early implant removal group (Group B,17 patients).Group A was given debridement and anti infection treatment followed by continuous dressing change,and the implant was removed after the fractures were healed.Group B was given debridement and implant removal after one month of anti infection treatment and continuous dressing change when the infection was not clearly controlled.Patients with stable fracture ends were given only negative pressure closed drainage (VSD),and those with instable fracture ends were given external fixation and VSD.The time from infection to implant removal,the time of infection control,the fracture nonunion rate,the chronic bone infection rate,the knee joint function score of the American Hospital for Special Surgery (HSS),and the American Orthopedic Foot and Ankle Society (AOFAS) ankle hindfoot scale were compared between the two groups.Results All patients were followed up for 13-47 months,with the average of 28.4 months.There were significant differences between Group A and Group B in terms of the time from infection to implant removal [(49.9 17.1) weeks ∶ (19.3 ± 9.2) weeks],the time of infection control [(85.3 ±78.3)days∶ (6.3 ±2.8)days],fracture nonunion rate (30％ ∶ 0),and the chronic osteomyelitis incidence (30％ ∶ 0) (all P ＜0.05).No significant differences were found in HSS knee joint function score and AOFAS ankle hindfoot scale between the two groups (both P ＞ 0.05).Conclusion For patients with postoperative infection after internal fixation for tibial fracture,early thorough debridement and implant removal can quickly control the infection and reduce the incidence of nonunion and osteomyelitis.

Objective To investigate the three-dimensional morphological characteristics of tibial plateau based on CT image post-processing technique and analyze its significance in preoperative planning of tibial plateau fractures.Methods Multi-slice spiral CT data of 98 humans (56 males and 42 females) with normal tibial plateau and 30 patients (15 males and 15 females) with tibial plateau fractures were extracted.Morphological measurements of the tibial plateau were achieved by means of a three-dimensional measurement method based on points,lines and surfaces.Differences in threedimensional parameters between genders in normal tibial plateau and differences between normal tibial plateau and tibial plateau fractures were analyzed.Results Differences of males and females were significant in width of tibial plateau [(73.2 ± 3.7) mm,(65.5 ± 3.7) mm],anteroposterior dimension of medial tibial plateau [(39.8 ± 3.5) mm,(34.8 ± 2.6) mm] and anteroposterior dimension of lateral tibial plateau [(34.0 ± 3.3) mm,(29.8 ± 3 5) mm] (P ＜ 0.05),but not in varus inclination of tibial plateau [(3.19 ± 1.98) °,(3.16 ± 1.89) °],medial plateau posterior slope [(7.31 ± 3.04) °,(8.16 ± 2.46)°] and lateral plateau posterior slope [(5.23 ±2.35)°,(5.60 ±2.55)°] (P ＞0.05).Above parameters in three-dimensional morphological measurements of tibibial plateau fractures varied compared to the normal reference value (P ＜ 0.05).Intraclass correlation coefficient (ICC) for intra-observe and inter-observer agreement in normal tibial plateau measurement was excellent.Conclusions Present research provides a series of scientific and objective data for preoperative planning of tibial plateau fractures.Measurements of tibial plateau can assist the evaluation of reduction of tibial plateau fractures.

Objective To discuss the curative effect of computer assisted pre-operation plan (CAPP) in treating the geriatric intertrochanteric femoral fracture.Methods The data of intertrochanteric fractures treated with PFNA-Ⅱ between March 2012 and June 2015 were retrospectively analyzed.They were divided into two groups by preoperative design.One group was the CAPP group consisting of 53 patients with a mean age of 75.3 years (range,60-92 years).According to the Evans Classification,there were 12 Evans type Ⅰb,9 Evans type Ⅰc,15 Evans type Ⅰd and 17 Evans type Ⅱ fractures.The other group was the non-CAPP group consisting of 74 patients with a mean age of 76.6 years (range,62-95 years).There were 18 Evans type Ⅰb,15 Evans type Ⅰc,20 Evans type Ⅰd and 21 Evans type Ⅱ fractures.Operation time,intraoperative blood loss,times of fluoroscopy during operation and days of hospital stay were compared.The hip joint function was evaluated by Harris score at the final follow-up.Results The CAPP meanly cost 24.7 min.The consistency of the surgery and CAPP was up to 100％.In the CAPP group,the average operation time was 46.8±6.5 min;the average times of fluoroscopy during operation were 12.0±2.3 times;and the average blood loss was 154.4±27.6 ml.In the non-CAPP group,the average operation time was 57.8±10.3 min;the average times of fluoroscopy during operation was 20.9±3.2;and the average blood loss was 235.0±65.8 ml.All above data in the CAPP group were significantly lower than those in the non-CAPP group.The mean days of hospital stay were 13.9±1.3 days in the CAPP group and 14.3±1.4 days in non-CAPP group.The days of hospital stay had no significant difference between the two groups.Forty-five patients with an average follow-up period of 18.3 months were reviewed in the CAPP group.Fifty patients were followed up with an average period of 19.2 months in the non-CAPP group.At the final follow-up,the average Harris score was 88.6±2.8 points (range,84-96 points) in the CAPP group and 87.5±3.2 points (range,80-95 points) in the non-CAPP group.Conclusion CAPP system is convenient and efficient.It can facilitate the treatment of intertrochanteric fracture effectively.

Objective To provide references for anatomical reduction and correct implantation in treatment of distal fibular fracture by analyzing morphological characteristics of distal fibula on three-dimensional (3D) modes.Methods 16-row spiral CT scans of 126 normal ankle structures from May 2009 to June 2014 were collected.Surface shaded display technique was used to reconstruct 3-D images of bones around the ankle.The distal fibula was extracted using 3D segmentation technique.The parameters of distal fibula were measured by selecting points,lines and surfaces on the 3D models.Results The morphological characteristics of distal fibula were complicated.Significant differences were observed between males and females in most parameters (P ＜ 0.05),but not in the length between the plane of the most lateral point of the tibial anterior node and the most distal point of the fibula,the length between the midpoint of lateral border of the fibula and its opposite cortex on the plane of the most proximal border of the fibular fossa or the mean angle of posterior crest of the fibula (P ＞ 0.05).The intra and interclass correlation coefficients (ICC) were excellent.Conclusions When a lateral plate is used for internal fixation of distal fibula,the plate should be placed as proximally as possible.When a posterior-lateral plate is used,the screws to be inserted on the plane proximal to the initial point of anterior node of the tibia can be fixed bi-cortically.When a posterior plate is used,pre-contour of the plate before insertion is required.