The purpose of this study was to compare the biomechanical stability obtained by using our technique featured an anatomical plate and compression bolts versus that of the conventional anatomic plate and cancellous screws in the fixation of intraarticular calcaneal fractures. Eighteen fresh frozen lower limbs of cadavers were used to create a reproductive Sanders type-III calcaneal fracture model by using osteotomy. The calcaneus fractures were randomly selected to be fixed either using our anatomical plate and compression bolts or conventional anatomic plate and cancellous screws. Reduction of fracture was evaluated through X radiographs. Each calcaneus was successively loaded at a frequency of 1 Hz for 1000 cycles through the talus using an increasing axial force 20 N to 200 N and 20 N to 700 N, representing the partial weight bearing and full weight bearing, respectively, and then the specimens were loaded to failure. Data extracted from the mechanical testing machine were recorded and used to test for difference in the results with the Wilcoxon signed rank test. No significant difference was found between our fixation technique and conventional technique in displacement during 20-200 N cyclic loading (P=0.06), while the anatomical plate and compression bolts showed a great lower irreversible deformation during 20-700 N cyclic loading (P=0.008). The load achieved at loss of fixation of the constructs for the two groups had significant difference: anatomic plate and compression bolts at 3839.6±152.4 N and anatomic plate and cancellous screws at 3087.3±58.9 N (P=0.008). There was no significant difference between the ultimate displacements. Our technique featured anatomical plate and compression bolts for calcaneus fracture fixation was demonstrated to provide biomechanical stability as good as or better than the conventional anatomic plate and cancellous screws under the axial loading. The study supports the mechanical viability of using our plate and compression bolts for the fixation of calcaneal fracture.

The purpose of this study was to compare the biomechanical stability obtained by using our technique featured an anatomical plate and compression bolts versus that of the conventional anatomic plate and cancellous screws in the fixation of intraarticular calcaneal fractures. Eighteen fresh frozen lower limbs of cadavers were used to create a reproductive Sanders type-III calcaneal fracture model by using osteotomy. The calcaneus fractures were randomly selected to be fixed either using our anatomical plate and compression bolts or conventional anatomic plate and cancellous screws. Reduction of fracture was evaluated through X radiographs. Each calcaneus was successively loaded at a frequency of 1 Hz for 1000 cycles through the talus using an increasing axial force 20 N to 200 N and 20 N to 700 N, representing the partial weight bearing and full weight bearing, respectively, and then the specimens were loaded to failure. Data extracted from the mechanical testing machine were recorded and used to test for difference in the results with the Wilcoxon signed rank test. No significant difference was found between our fixation technique and conventional technique in displacement during 20-200 N cyclic loading (P=0.06), while the anatomical plate and compression bolts showed a great lower irreversible deformation during 20-700 N cyclic loading (P=0.008). The load achieved at loss of fixation of the constructs for the two groups had significant difference: anatomic plate and compression bolts at 3839.6±152.4 N and anatomic plate and cancellous screws at 3087.3±58.9 N (P=0.008). There was no significant difference between the ultimate displacements. Our technique featured anatomical plate and compression bolts for calcaneus fracture fixation was demonstrated to provide biomechanical stability as good as or better than the conventional anatomic plate and cancellous screws under the axial loading. The study supports the mechanical viability of using our plate and compression bolts for the fixation of calcaneal fracture.
Biomechanical Phenomena ; physiology ; Bone Plates ; Fracture Fixation ; methods ; Fractures, Bone ; physiopathology ; surgery ; Humans ; Male ; Middle Aged

Objective To investigate the efficacy and safety of intravesical instillation of BCG vaccine in the prevention of early recurrence of middle and high risk non-muscle invasive bladder cancer.Methods From July 2015,patients with non-muscle invasive bladder cancer aged 18-75 years with informed consent were screened and underwent transurethral resection of bladder tumor (TURBT).Immediately intravesical instillation of epirubicin 50 mg was given postoperatively.After pathology was comfirmed,patients was enrolled in group 1 (BCG15) or group 2 (BCG 19) or the control group (epirubicin 18) randomly with SAS 9.3 software.Data of follow-up and Adverse event was collected and analyzed.Results By May 31,2019,531 patients were enrolled in the study.The drop-off rate was 20.1％.167 patients (143 males and 24 females)in group 1,172 patients (141 males and 31 females)in group2 and 84(75 males and 9 females) in the control group with follow-up data were analyzed.There were no significant differences in age,gender,BMI,ECOG score,risk stratification between the three groups (P =0.8641,P =0.2906,P =0.9384,P =0.6126).The median follow-up time makes no statistical difference between the groups (P =0.9251),12.0 (6.0,22.5) months,13.0 (6.0,22.3) months,and 13.0 (7.0,22.3) months.The median recurrence time of the three groups was 4.0 (3.0,6.0) months,4.5 (3.0,9.8) months,4.5 (3.0,8.8) months.There was no statistical difference between the three groups (P =0.2852).Risk stratification in the patients got no significant difference between the three groups (P ＞ 0.05).The 1-year recurrence-free survival rates were 80.0％ in the group 1 and 88.3％ in the group 2 and 73.7％ in the control group.The group 2 was superior to the group 1 and the control group (P =0.0281,P =0.0031).There was no significant difference between group 1 and control group (P =0.2951).There was no significant difference in the cumulative recurrence-free survival between the experimental group 1 and the experimental group 2,(95％ CI 0.80-2.43,P =0.2433).The cumulative recurrence-free survival in the group 1 and the group 2 was better than the control group (95 ％ CI 0.31-0.92,P =0.0266;95 ％ CI 0.20-0.65,P =0.0008).All the cases underwent instillation were analyzed for adverse events.The incidence of overall AE(adverse events) in group 1 was 68.5％ (152/222),the incidence of grade Ⅰ-Ⅱ AE was 53.2％ (118/222),the incidence of grade Ⅲ-Ⅳ AE was 15.3％ (32/222).The incidence of overall AE in the group 2 was 71.8％ (160/223),the incidence of grade Ⅰ-Ⅱ AE was 60.1％ (134/223),and the incidence of grade Ⅲ-Ⅳ AE was 11.7％ (26/223).The overall AE rate in the control group was 53.2％ (59/111),of which the incidence of grade Ⅰ-Ⅱ AE was 42.4％ (47/111),and the incidence of grade Ⅲ-Ⅳ AE was 10.8％ (12/111).There was no difference in the incidence of overall AE between the group 1 and the group 2 (P =0.4497).The incidence of AE in the two experimental groups was higher than that in the control group (P =0.0062,P =0.0008).There was no difference in the incidence of grade Ⅲ-Ⅳ AE between the three groups (P =0.3902).Conclusions BCG(19 instillation schedule) has a better effect on preventing recurrence after 1 year of bladder surgery,which is superior to epirubicin group.The long-term efficacy of BCG in preventing recurrence and the efficacy of different schedules need to be further followed up.The lower urinary tract symptoms,which are mainly urinary frequency,are one of the causes of case fallout and should be fouced in future.Compared with epirubicin,BCG perfusion does not increase the incidence of grade Ⅲ-Ⅳ adverse reactions,and is safe to use.