OBJECTIVE: To compare the biomechanical differences among the five internal fixation modes in treatment of Day type Ⅱ crescent fracture dislocation of pelvis (CFDP), and find an internal fixation mode which was the most consistent with mechanical principles. METHODS: Based on the pelvic CT data of a healthy adult male volunteer, a Day type Ⅱ CFDP finite element model was established by using Mimics 17.0, ANSYS 12.0-ICEM, Abaqus 2020, and SolidWorks 2012 softwares. After verifying the validity of the finite element model by comparing the anatomical parameters with the three-dimensional reconstruction model and the mechanical validity verification, the fracture and dislocated joint of models were fixed with S ₁ sacroiliac screw combined with 1 LC-Ⅱ screw (S ₁+LC-Ⅱ group), S ₁ sacroiliac screw combined with 2 LC-Ⅱ screws (S ₁+2LC-Ⅱ group), S ₁ sacroiliac screw combined with 2 posterior iliac screws (S ₁+2PIS group), S ₁ and S ₂ sacroiliac screws combined with 1 LC-Ⅱ screw (S ₁+S ₂+LC-Ⅱ group), S ₂-alar-iliac (S ₂AI) screw combined with 1 LC-Ⅱ screw (S ₂AI+LC-Ⅱ group), respectively. After each internal fixation model was loaded with a force of 600 N in the standing position, the maximum displacement of the crescent fracture fragments, the maximum stress of the internal fixation (the maximum stress of the screw at the ilium fracture and the maximum stress of the screw at the sacroiliac joint), sacroiliac joint displacement, and bone stress distribution around internal fixation were observed in 5 groups. RESULTS: The finite element model in this study has been verified to be effective. After loading 600 N stress, there was a certain displacement of the crescent fracture of pelvis in each internal fixation model, among which the S ₁+LC-Ⅱ group was the largest, the S ₁+2LC-Ⅱ group and the S ₁+2PIS group were the smallest. The maximum stress of the internal fixation mainly concentrated at the sacroiliac joint and the fracture line of crescent fracture. The maximum stress of the screw at the sacroiliac joint was the largest in the S ₁+LC-Ⅱ group and the smallest in the S ₂AI+LC-Ⅱ group. The maximum stress of the screw at the ilium fracture was the largest in the S ₁+2PIS group and the smallest in the S ₁+2LC-Ⅱ group. The displacement of the sacroiliac joint was the largest in the S ₁+LC-Ⅱ group and the smallest in the S ₁+S ₂+LC-Ⅱ group. In each internal fixation model, the maximum stress around the sacroiliac screws concentrated on the contact surface between the screw and the cortical bone, the maximum stress around the screws at the iliac bone concentrated on the cancellous bone of the fracture line, and the maximum stress around the S ₂AI screw concentrated on the cancellous bone on the iliac side. The maximum bone stress around the screws at the sacroiliac joint was the largest in the S ₁+LC-Ⅱ group and the smallest in the S ₂AI+LC-Ⅱ group. The maximum bone stress around the screws at the ilium was the largest in the S ₁+2PIS group and the smallest in the S ₁+LC-Ⅱ group. CONCLUSION For the treatment of Day type Ⅱ CFDP, it is recommended to choose S ₁ sacroiliac screw combined with 1 LC-Ⅱ screw for internal fixation, which can achieve a firm fixation effect without increasing the number of screws.
Adult ; Male ; Humans ; Finite Element Analysis ; Fracture Fixation, Internal/methods* ; Fractures, Bone/surgery* ; Pelvis ; Spinal Fractures/surgery* ; Fracture Dislocation/surgery* ; Joint Dislocations/surgery* ; Biomechanical Phenomena

OBJECTIVE: To investigate the effectiveness of osteotomy of non-core weight-bearing area of the lateral tibial plateau, reduction, and internal fixation in the treatment of tibial plateau fractures involving posterolateral column collapse. METHODS: A clinical data of 23 patients with tibial plateau fractures involving posterolateral column collapse, who had undergone osteotomy of non-core weight-bearing area of the lateral tibial plateau, reduction, and internal fixation between January 2015 and June 2021, was retrospectively analyzed. There were 14 males and 9 females with an average age of 42.6 years ranging from 26 to 62 years. The causes of injury included traffic accident in 16 cases, falling from height in 5 cases, and other injuries in 2 cases. According to Schatzker classification, there were 15 cases of type Ⅴ and 8 cases of type Ⅵ. The time from injury to operation was 4-8 days with an average of 5.9 days. The operation time, intraoperative blood loss, fracture healing time, and complications were recorded. The depth of articular surface collapse of posterolateral column and posterior inclination angle (PSA) of the tibial plateau were compared before operation and at 2 days and 6 months after operation; fracture reduction of tibial plateau fracture was evaluated by Rasmussen anatomic score. The recovery of knee function was evaluated by Hospital for Special Surgery (HSS) score at 2 days and 6 months after operation. RESULTS: All 23 patients were completed the operation successfully. The operation time was 120-195 minutes, with an average of 152.8 minutes; the intraoperative blood loss was 50-175 mL, with an average of 109.5 mL. All patients were followed up 12-24 months, with an average of 16.7 months. One patient had superficial wound infection after operation, and the incision healed after dressing change; primary healing of incision of other patients was obtained. The fracture healing time was 12-18 weeks, with an average of 13.7 weeks. No failure of internal fixation, varus and valgus deformity of the knee joint, and instability of the knee joint was found at last follow-up. One patient developed joint stiffness and the range of motion of the knee joint was 10°-100°; the range of motion of the knee joint of other patients was 0°-125°. At 2 days and 6 months after operation, the depth of articular surface collapse of posterolateral column, PSA, and Rasmussen anatomic scores significantly improved when compared with those before operation ( P<0.05). There was no significant difference between the two postoperative time points ( P>0.05). The HSS score at 6 months after operation was significantly higher than that at 2 days after operation ( P<0.05). CONCLUSION For tibial plateau fractures involving posterolateral column collapse, reduction and internal fixation through osteotomy of non-core weight-bearing area of the lateral tibial plateau has the advantages of fully expose the posterolateral column fragment, good articular surface reduction, sufficient bone grafting, and fewer postoperative complications. It is beneficial to restore knee joint function and can be widely used in clinic.
Male ; Female ; Humans ; Adult ; Retrospective Studies ; Blood Loss, Surgical ; Tibial Plateau Fractures ; Treatment Outcome ; Bone Plates ; Tibial Fractures/surgery* ; Knee Joint ; Fracture Fixation, Internal ; Osteotomy ; Weight-Bearing

Objective:To investigate the preoperative ascending aorta diameter in patients with acute type A aortic dissection in the Chinese population, compares and analyze the differences in preoperative blood biomarkers, and evaluate the impact of the preoperative ascending aorta diameter in this part of patients on the short-term prognosis of patients.Methods:A collection of 641 patients with acute type A aortic dissection who were enrolled in the " Acute Aortic Syndrome High-Risk Early Warning and Intervention Study" project from January 2018 to January 2020 were collected. Divide the patients into two groups (group Ⅰ<55 mm, group Ⅱ≥55 mm) according to the preventive intervention value of ascending aorta diameter recommended by the guideline for studying preoperative ascending aorta diameter difference in blood biomarkers and the influence of ascending aorta diameter on the short-term prognosis of patients. All patients had CT scans to assess the diameter of the ascending aorta before operation.Results:In this study, all patients with acute type A aortic dissection had a mean preoperative ascending aorta diameter of (46.9±9.7)mm. The preoperative ascending aorta diameter of all patients was less than 55 mm, accounted for 84.1%. Male patients were more likely to have aortic dissection than females; most patients' age was less than 60 years old. The preoperative blood inflammatory index counts were higher in the ascending aorta diameter ≥55 mm group. However, the long-term prognosis of patients with different ascending aorta diameters before surgery was not apparent in this study. The preoperative survival rate and short-term survival rate of patients with ascending aorta diameter <55 mm were higher than those of other groups, but the difference was not statistically significant.Conclusion:In patients with acute type A aortic dissection, the diameter of the ascending aorta is usually less than 55 mm. Moreover, the blood inflammatory index counts are high in the preoperative ascending aorta diameter ≥55 mm group. Meanwhile, patients with smaller ascending aorta diameter have better survival rate and short-term prognosis.

Objective    To evaluate the preoperative risk factors for acute Stanford type A aortic dissection (ASTAAD) patients in our country by collecting multi-center data. Methods    We consecutively enrolled 700 patients who underwent surgery for ASTAAD in the multi-center hospital database from January 2018 to January 2020. According to the ascending aorta size (AAS), the patients were divided into two groups: a group AAS≥55 mm and a group AAS< 55 mm. Univariate and multivariate logistic regression analyses were used to investigate the related preoperative risk factors for the onset of ASTAAD. Results    According to the exclusion criteria, a total of 621 patients were finally enrolled, including 453 males and 168 females with an average age of 48.24±11.51 years, and 509 (81.94%) patients had AAS< 55 mm. Univariate and multivariate statistical analyses showed that smoking, hypertension, preoperative cardiac troponin I, and left ventricular ejection fraction were related to the occurrence of ASTAAD. The mortality rate of the patient during hospitalization was 13.04% (81 patients). Conclusion    In clinical practice, various preoperative risk factors affect ASTAAD patients, which should be paid attention to. Comprehensive evaluation and an individualized analysis of patients and timely prevention and intervention improve patients' survival rate.

Objective:To compare the clinical outcome of navigation-assisted percutaneous cannulated screw fixation and posterior percutaneous plate fixation for Day type II crescent fracture dislocation of pelvis (CFDP).Methods:A retrospective cohort analysis was performed on clinical data of 40 patients with Day type II CFDP treated in General Hospital of Central Theater Command of PLA from January 2012 to June 2021. There were 23 males and 17 females, with age range of 42-73 years [(54.2±7.8)years]. A total of 19 patients were treated with navigation-assisted percutaneous cannulated screw fixation (navigation group) and 21 with posterior percutaneous plate fixation (plate group). The incision length, operation time, intraoperative blood loss and in-hospital time were compared between the two groups. The reduction quality was evaluated by Matta radiographic standard at day 2 after surgery. The functional recovery was assessed by Majeed functional score at 3 and 6 months after surgery. The postoperative complications were observed.Results:All patients were followed up for 10-24 months [(13.6±2.9)months]. The incision length, operation time, intraoperative blood loss and in-hospital time was (2.4±0.3)cm, (43.1±5.2)minutes, (48.4±18.4)ml and (14.4±1.9)days in navigation group, showing significant difference compared with plate group [(8.8±0.4)cm, (132.2±19.4)minutes, (302.9±57.5)ml, (18.9±3.7)days] (all P<0.01). According to Matta radiographic standard at day 2 after surgery, the excellent and good rate was 89% in navigation group (excellent in 13 patients, satisfactory in 4 and poor in 2) and 95% in plate group (excellent in 15 patients, satisfactory in 5 and poor in 1) ( P>0.05). According to Majeed criteria at 3 months after surgery, the excellent and good rate was 89% in navigation group (excellent in 12 patients, good in 5 and poor in 2) and 95% in plate group (excellent in 15 patients, good in 5 and poor in 1) ( P>0.05). According to Majeed criteria at 6 months after surgery, the excellent and good rate was 95% in navigation group (excellent in 14 patients, good in 4 and poor in 1) and 95% in plate group (excellent in 17 patients, good in 3 and poor in 1) ( P>0.05). There was no iatrogenic neurovascular injury. The incidence of complications was 11% (2/19) in navigation group, including one patients with sacroiliac screw loosening and one with posterior iliac screw penetrating the medial cortex of the bone, while that was 29% (6/21) in plate group, including two patients with skin tenderness, two with deep vein thrombosis in the lower extremity and two with incision infection ( P<0.05). Conclusions:For Day type II CFDP, both navigation-assisted percutaneous cannulated screw fixation and posterior percutaneous plate fixation can attain satisfactory efficacy, but the former has advantages of shorter operation time, less surgical trauma, less bleeding, shorter in-hospital time and lower incidence of complications.

Objective:To investigate the clinical effect of peroneal fracture line in the treatment of posterior Pilon fracture.Methods:The data of 26 patients treated with fibular fracture line from January 2017 to July 2019 were analyzed retrospectively, including 11 males and 15 females; the age ranged from 28 to 69 years, with an average of 42.2 years. There were 10 cases of falling injury, 9 cases of falling injury and 7 cases of traffic injury; all of them were fresh closed fibular fractures;According to Yu Guangrong's classification, there were 11 cases of type I, 8 cases of type II and 7 cases of type III; AGH was divided into 10 cases of type I, 5 cases of type IIa, 2 cases of type IIb, 5 cases of type IIIa and 4 cases of type IIIb. All cases were treated by opening the fibular fracture line through the posterolateral approach, the quality of fracture reduction was evaluated by Burwell Charnley radiological evaluation standard after operation; At the last follow-up, ankle function was evaluated by American Association of Foot and Ankle surgery (AOFAS) ankle and hindfoot scores.Results:All 26 patients were followed up for 12-23 months, with an average of 14.9 months; Bone healing was achieved in all fractures. The healing time was 3-6 months, with an average of 4.0 months. The quality of fracture reduction was evaluated according to the Burwell Charnley radiology evaluation standard after operation, including anatomical reduction in 23 cases and acceptable reduction in 3 cases. The anatomical reduction rate was 88% (23/26). At the last follow-up, AOFAS ankle and hindfoot scores ranged from 80 to 100, with an average of 89.9 points, of which 17 cases were excellent and 9 cases were good, and the excellent and good rate was 100%. At the last follow-up, no patient had complications such as reduction loss, skin necrosis, infection, internal fixation loosening or ankle stiffness.Conclusion:After the treatment of Pilon fractures via peroneal fracture line, the distal tibial articular surface and posterior ankle fracture gap can be fully exposed, which can be repositioned and fixed under direct vision, with high anatomical repositioning rate and good and safe clinical results.

Objective:To evaluate the clinical results of miniplates combined with reconstruction plate in treating comminuted posterior wall acetabular fractures.Methods:A retrospective case series study was conducted for 27 patients with comminuted posterior wall acetabular fractures treated in General Hospital of Central Theatre Command of PLA from October 2015 to June 2019. There were 18 males and 9 females, at age of 23-61 years［（45.9±10.9）years］. All patients were treated by using miniplates combined with the reconstruction plate. The operation time, intraoperative blood loss, intraoperative blood transfusion, length of hospital stay and time of fracture healing were recorded. The reduction quality was evaluated according to Matta radiographic standard at 2 days postoperatively. The modified Merle D'Aubigné-Postel score was adopted to evaluate the hip function at 3, 6 months postoperatively and the final follow-up. Postoperative complications were observed, and heterotopic ossification was assessed by Brooker grading standard.Results:All patients were followed up for 12-48 months［36（24, 36）months］. The operation time was 123-242 minutes［（165.4±29.8）minutes］; the intraoperative blood loss was 170-550 ml［（358.3±111.3）ml］; nine patients required intraoperative blood transfusion of 300-500 ml［（377.8±66.7）ml］. The length of hospital stay was 12-29 days［（21.4±4.7）days］. The fracture healing time was 12-24 weeks［（16.3±3.0）weeks］. According to Matta radiographic standard, the reduction quality was excellent in 21 patients, good in 3 and poor in 3 at 2 days postoperatively, with the excellent rate of 89%. The modified Merle D'Aubigné-Postel score was 9-16 points［（13.1±1.9）points］at 3 months postoperatively, was 10-18 points［（15.4±2.0）points］at 6 months postoperatively, and was 12-18 points［（16.9±1.8）points］at last follow-up（ P<0.01）. The modified Merle D'Aubigné-Postel score between 3 months and 6 months was significantly different（ P<0.01）, and the difference between 6 months and the follow-up was statistically significant（ P<0.01）. The modified Merle D'Aubigné-Postel score was graded as excellent in 0 patient, good in 7, fair in 11 and poor in 9 at 3 months postoperatively, with the excellent rate of 26%; graded as excellent in 3 patients, good in 19, fair in 2 and poor in 3 at 6 months postoperatively, with the excellent rate of 81%; graded as excellent in 18 patients, good in 5, fair in 3 and poor in 1 at the last follow-up, with the excellent rate of 85%（ P<0.01）. No iatrogenic sciatic nerve injury, deep vein thrombosis or wound infection occurred after operation. No hardware loosening or loss of reduction occurred during the follow-up. The post-traumatic arthritis was identified in 2 patients. The avascular necrosis of femoral head was observed in 1 patient and thereafter underwent total hip replacement. The heterotopic ossification occurred in 3 patients, among which 2 patients were graded as Brooker class I and 1 as class II, but there was no adverse effect on hip function. Conclusions:Miniplates combined with reconstruction plate in the treatment of comminuted posterior wall acetabular fractures have reliable fixation effect and attain good reduction, high fracture healing rate, less complications and satisfactory functional recovery.

Objective:To compare the effect of interlocking intramedullary nail and locking plate in the treatment of varus proximal humeral fractures in the elderly.Method:A retrospective case-control study was conducted to analyze the clinical data of 46 elderly patients with varus proximal humeral fractures treated in Central Theater General Hospital of PLA from June 2016 to January 2019, including 27 males and 19 females, at age of 60-84 years［（71.9±5.7）years］. All fractures were fresh. Overall 25 patients were treated with interlocking intramedullary nail（intramedullary nail group）, and 21 patients were treated with locking plate（bone plate group）. The incision length, operation time, intraoperative bleeding and fracture healing time were compared between the two groups. Visual analogue scale（VAS）was used to evaluate the degree of pain relief at 1 week and 1 month after operation, and Constant-Murley score was used to evaluate the recovery of shoulder function at 1 month, 3 months and 1 year after operation. The cervical trunk angle was recorded at 2 days and 1 year after operation to judge whether there was a loss of cervical trunk angle. Postoperative complications were observed.Results:All patients were followed up for 12-32 months［（19.7±6.6）months］. The incision length［（7.1±0.6）cm］, operation time［（60.8±5.2）minutes］, intraoperative bleeding［（64.4±8.4）ml］and fracture healing time［（10.0±1.0）weeks］in intramedullary nail group were significantly less than those in bone plate group［（13.6±0.9）cm,（80.2±8.1）minutes,（151.0±15.2）ml,（11.0±1.5）weeks］（ P<0.05）. In both groups, the VAS decreased significantly over time, and markedly increased Constant-Murley score was detected as well（ P<0.05）. The VAS in intramedullary nail group［（2.8±0.2）points,（1.1±0.2）points］was significantly lower than that in bone plate group［（4.0±0.2）points,（1.5±0.1）points］at 1 week and 1 month after operation（ P<0.05）. The Constant-Murley score in intramedullary nail group［（59.9±6.9）points,（79.1±6.8）points］was higher than that in bone plate group［（50.1±8.5）points,（73.6±8.4）points］at 1 month and 3 months after operation（ P<0.05）, but the score showed no significant difference between intramedullary nail group［（89.1±5.3）points］and bone plate group［（86.4±6.4）points］at 1 year after operation（ P>0.05）. According to Constant-Murley score, 10 patients were evaluated as excellent and 15 patients as good in intramedullary nail group at 1 year after operation, with the excellent and good rate of 100%, while 8 patients were evaluated as excellent, 11 patients as good and 2 patients as fair in bone plate group at 1 year after operation, with the excellent and good rate of 91%（ P>0.05）. The cervical trunk angle in intramedullary nail group［（140.2±2.9）°,（139.6±2.3）°］had significant difference from that in bone plate group［（139.6±3.2）°,（138.8±3.3）°］at 2 days and 1 year after operation（ P<0.05）. In both groups, the cervical trunk angle had slight lost at 1 year after operation compared with that at 2 days after operation, but the difference was not statistically significant（ P>0.05）. In intramedullary nail group, 1 patient had subacromial impact. In bone plate group, 1 patient had screw cutting, 2 patients subacromial impact, and 2 patients delayed fracture healing. The incidence of complications in intramedullary nail group was 4%（1/25）, lower than 24%（5/21）in bone plate group（ P<0.05）. Conclusion:Compared with locking nail plate, interlocking intramedullary nail in the treatment of senile varus proximal humeral fracture has the advantages of small trauma, early fracture healing, less pain, early function recovery and less complications.

Objective:To investigate the physical indices and growth status of preterm children aged 0 to 4 years with different birth weight.Methods:Following the real world research approach, the current study retrospectively collected e-chart information of 8 496 preterm children from the child health care system of the Children′s Hospital of Chongqing Medical University from December 2010 to December 2017, with 203 123 full-term children followed up during the same period as controls. Premature children were divided into normal birth weight (NBW) group, low birth weight (LBW) group, and very low birth weight (VLBW) group based on their birth weights. The weight and length development within 48 months of age of preterm boys and girls in each group were measured and recorded to establish a numerical table and analyze the growth levels, growth rate, and proportionality. The t-test or chi-square test was used for between-group comparison. Results:Of the 8 496 preterm children, 4 839 were girls and 3 657 boys, including 525 in the VLBW group, with an average birth weight of (1.28±0.14) kg, 3 862 in the LBW group, with an average birth weight of (2.07±0.28) kg, and 4 109 in the NBW group, with an average birth weight of (2.86±0.35) kg. The weight at the actual age of 2-<3 months ((5.61±0.96) vs. (5.64±0.78) kg in boys, (5.11±0.67) vs. (5.18±0.71) kg in girls) and the length at the actual age of 8-<10 months ((70.3±2.4) vs. (70.6±2.4) cm in boys, (68.9±2.2) vs. (68.9±2.4) cm in girls) in the NBW group reached the average weight and length of full-term children. The difference of physical growth before 24 months of age between LBW and control group decreased as children age, with that of LBW group approaches the average of full-term children after 24 months of age, with a weight difference of 0.64-0.95 kg and height difference of 1.3-1.7 cm. The weight and height of the VLBW group were lower than those of full-term infants (2.80-2.86 kg and 3.3-4.3 cm, respectively) at 48 months of age. During 2-12 months of age, the corresponding values of the VLBW group were higher than that of the LBW and NBW groups by 0.35 kg and 0.71 kg, respectively. However, the corresponding values of the VLBW group were lower than that of the LBW and NBW groups(0.64 kg and 0.76 kg at 0-2 months of age, 1.04 kg and 1.49 kg at 12-48 months of age, respectively). The rates of delayed development, underweight, and emaciation were the highest in the VLBW group (all P<0.01), while the rates of overweight and obesity were the highest in the NBW group, with that of the VLBW group being lower than LBW group ( P<0.01) at the age of 24-<36 months. Conclusions:Prior to 4 years of age, the time for preterm children to reach the average physical indices of full-term children differ by birth weights, hence warranting further examination of the corrected gestational age for preterm children. Normal birth weight preterm children present with the highest incidence of overweight and obesity and very low birth weight preterm children present with the highest incidence of growth disorders, marking both groups at high risks of malnutrition.

Objective To analyze the characteristics of dynamic contrast enhanced MR imaging (DCE-MRI)in prostate cancer (PCa)at 3.0T,and to evaluate the diagnostic value of DCE-MRI.Methods 85 patients with suepected PCa received conventional MRI and DCE-MRI.The signal intense-time (SI-T)curve was analyzed.Then the time to maximum (Tmax),the maximum degree of enhancement (STmax%),and the rate of enhancement (Rmax)were calculated.The differences of styles of SI-T curve and the parameters between the positive and negative group were compared respectively.Results 59 cases of PCa were proved by biopsy,and there was no evidence of tumor in 26 cases.507 zones had histopathological results with 250 zones in positive group and 257 zones in negative group .The most common style of SI-T curve in positive group was rapidly ascending followed with descending curve,the most common style of SI-T curve in negative group was persistent ascending curve and plateau curve.The mean values of Tmax,SImax%,Rmax were (69.49±22.53)s,1.74±0.43,7.83±3.80 in positive group respectively,while (175.61±52.64)s,1.05±0.35,1.86±1.10 in negative group respectively,there were statistically significant differences between the two groups(t =-24.24,1 6.34,1 7.75,P <0.01)respectively. The mean values of Tmax,SImax% ,Rmax were (8 9 .1 9 ± 3 1 .7 2 )s,1 .5 8 ± 0 .4 6 ,5 .2 1 ± 3 .3 4 in the low-risk group (Gleason score 2 - 6 )respectively,while (64.25±14.68)s,1.76±0.43,8.25±3.70 in the high-risk group (Gleason score 7-10)respectively, there were statistically significant differences between them(t = 7.09,-8.74,- 7.83,P <0.01).Conclusion 3.0T DCE-MRI has great value in the diagnosis of PCa.