Objective To investigate the value of electromagnetic field real-time system (EFRTS) in the distal locking of intramedullary nailing for humeral shaft fractures.Methods From April 2015 to January 2017,data of 32 consequent patients with humeral shaft fracture (22 males,10 females;ranged from 18 years to 78 years old,average of 40.4 years;9 domestic falls,15 traffic accidents,6 fall from height,and 2 sports injury;AO12 A1:9 cases;A2:14 cases;A3:4 cases;B2:5 cases) were retrospectively analyzed.All were treated with Humeral Antegrade Locking Nail.For inserting the two distal locking screws,the SURESHOT Distal Targeting System was used.Results Accurate placement of the distal screws was accomplished in all 32 cases,which meant one drilling and one screw locking.The mean duration of the two distal screw locking was 197±30 s (range,156-253 s) in the preparation phase and 393±39 s (range,336-481 s) in the operation phase.The mean follow-up period was 18 months,ranging from 11 to 25 months.All the fractures were healed in an average time of 15.9 weeks,ranging from 12 to 20 weeks.The range of motion was:80° to 180° in abduction (155° in average),80° to 180° in anteflexion (160° in average),60° to 100° in external rotation (80° in average),and 17 cases internal rotation to L3 level,10 to T12 level and 5 to T7 level.The mean score of ConstantMurley was 89,ranging from 74 to 96.All the patients obtained good results.27 patients restored self-care ability within 3 months after surgery.Shoulder discomfort occurred in 2 patients because of nail tail outside the articular surface.The symptom recovered after removal of the nail as well as joint release in arthroscopy.Conclusion The distal aiming device can be used in humeral intramedullary nailing,by which the distal screw can be inserted by one time.Meanwhile,it has the advantages of short time-consuming,secure operation,and no X-ray radiation.

Objective:To evaluate the hemostatic efficacy of N-carboxyethylchitosan fiber gauze (numbered NWL-K) in a leporine bleeding wounds of intraperitoneal parenchymal visceral.Methods:Sixty New Zealand rabbits were divided into two groups according to the randomized digital number method, with 30 rabbits per group. The leporine bleeding models of hepatic or splenic wound were made respectively. The two groups were subdivided into three groups: common gauze group, SURGICEL group and NWL-K group, with 10 rabbits per group. By analyzing the weight of excised liver tissue and amount of bleeding, the model stability was measured. The time to hemostasis and bleeding score in each group were analyzed every (20±5)seconds after compression for 30 seconds in the hepatic bleeding models or every (30±5)seconds after compression for 3 minutes in the splenic bleeding models. The adhesion between wound and gauze was evaluated at the same time.Results:There was no significant difference in the weight of excised liver tissue and amount of bleeding when the hepatic or splenic bleeding models were made ( P>0.05). It showed that the model was made stably and the hemostasis experiment would not be affected. In the splenic wound model experiment, the time to hemostasis was 255(233, 300)seconds in SURGICEL group and 210(180, 248)seconds in NWL-K group, both of which were significantly shorter than 465(383, 660)seconds in common guaze group ( P<0.05). NWL-K achieved shorter time to hemostasis than SURGICEL ( P<0.05). In the hepatic wound model experiment, the time to hemostasis was 90(85, 110)seconds in SURGICEL group and 70(70, 95)seconds in NWL-K group, both of which were significantly shorter than 250(225 290)seconds in common gauze group ( P<0.05). In the splenic wound model experiment, the bleeding score in NWL-K group and SURGICEL group decreased faster than that in common gauze group ( P<0.05). The difference of bleeding score was significant between NWL-K group and SURGICEL group at 180 seconds ( P<0.05). In the hepatic wound model experiment, the bleeding score in NWL-K group and SURGICEL group decreased faster than that in common gauze group at 50 seconds, 70 seconds and 90 seconds ( P<0.05). The bleeding score in common gauze group and NWL-K group showed significant difference at 30 seconds, 110 seconds and 130 seconds ( P<0.05). For the adhesion evaluation, both the water-absorbency and adhesion to tissue of NWL-K were better than common gauze and SURGICEL. Conclusions:For hepatic and splenic bleeding wounds, compared with other types of gauze, the application of NWL-K can effectively shorten the time to hemostasis and reduce the blood loss. The NWL-K shows high water-absorbency and firm adhesion to bleeding wound.