Testing System for Biomechanical Properties of Bone / 中国医疗器械杂志

A novel testing system is designed to simulate the mechanical performance and evaluate the biomechanical properties of the bone and the corresponding bone fixator. It is mainly composed of movement platform and servo motor system, sensors and hardware circuit system and software system. In order to prove the feasibility of the design, on the basis of the calibration for the force sensor, the fatigue experiment is carried out using the tibia of the sheep. It is concluded from the result that under the condition of 1 Hz in frequency, 50 kg in loading force and 18 000 cycles, the bone fixator can be still in good condition, which proves the feasibility of the design.

External pelvic reduction frame system combined with tunnel screw fixation for Tile C1 pelvic fracture / 中华创伤杂志

Objective To investigate the efficacy of external pelvic reduction frame system combined with tunnel screw fixation in the treatment of Tile C1 pelvic fracture.Methods A retrospective case series analysis of 15 patients with Tile C1 pelvic fractures from January 2014 to October 2016 was pedormed.Clinical data included seven males and eight females,aged 26-84 years (mean,48.9 years).According to Tile classification,there were five cases of type C1.1,three cases of C1.2,and seven cases of type C1.3.The average time from injury to surgery was 9.5 days (range,4-33 days).All patients received the treatment of external pelvic reduction frame system combined with tunnel screw fixation.The operation time,intraoperative blood loss,and complications were recorded.The fracture reduction quality was evaluated according to the Matta criteria,and the clinical function and neurological function were evaluated by the Majeed functional scoring system and the Gibbons sacral nerve injury grading,respectively.Results The patients were followed up for an average of 16 months (range,12-24 months).The mean operation time was 139 minutes (range,50-250 minutes),and the mean intraoperative blood loss was 90 ml (range,20-260 ml).No complications such as wound infection,loose internal fixation,rupture or loss of reduction occurred in the patients.According to the Matta score,14 patients obtained anatomical reduction,and one obtained satisfactory reduction.At the last follow-up,according to the Majeed functional scoring criteria,the results were excellent in all 15 patients,with an excellent and good rate of 100％.According to Gibbons sacral nerve injury grading,two out of the three patients with neurologic impairment before the operation recovered completely while the remaining one did not recover.Conclusion In the treatment of Tile C 1 pelvic fractures,external pelvic frame reduction system combined with tunnel screw fixation can attain satisfactory fracture reduction,reliable fixation,and good functional recovery.

Analysis of efficacy on calcaneal fracture by plate fixation combined with 64-slice CT 3D reconstruction / 医疗卫生装备

Objective To treat calcaneal fracture with plate fixation combined with 64-slice CT 3D reconstruction and to analyze the efficacy.Methods Totally 86 patients with Sanders Ⅲ and Ⅳ types of calcaneal fractures underwent surgical treatment,and 64-slice CT 3D reconstruction was used to record the length,height,width,Bohler angle and Gissane angle of calcaneus before and 1 d,2 d,3 d and 1 a after the treatment.Postoperative evaluation was executed based on AOFAS Ankle Hindfoot Scale.Results All the fractures healed,of which,there were 60 ones scored as excellence,19 ones in good condition and 7 ones in satisfactory condition with the excellence and goodness rate being 91.9％.Complications occurred in 4 patients,with 3 cases of delayed healing and one case of infection.Tbere were obviously differences between the lengths,heights,widths,Bohler angles and Gissane angles before and after the treatment,while the differences were not significant between the measured values 1 d and 1 a after the treatment.Conclusion 64-slice CT 3D reconstruction is an excellent clinical auxiliary tool,and is of great value for fracture typing,operational plan preparation,postoperative evaluation and late efficacy assessment.

Percutaneous osteoperiosteal decortication combined with distraction osteogenesis for treatment of nonunion of lower-extremity bones / 中华创伤骨科杂志

Objective To evaluate the curative effects of percutaneous osteoperiosteal decortication combined with distraction osteogenesis for treatment of nonunion of lower-extremity bones.Methods A retrospective analysis was performed of the 32 patients who had been treated using osteoperiosteal decortication combined with distraction osteogenesis from September 2011 to December 2014 for nonunion of lower-extremity fractures.They were 23 males and 9 females,with a mean age of 33.4 years (range,from 15 to 62 years).After their former internal or external fixators were removed,the 2 fracture ends were fixated by a retractile mono-lateral or circular external fixator.Under radiographic monitoring,a percutaneous incision was made with a 5 mm sharp chisel,down to the bone.Scar and ossified tissue between the fracture ends were debrided and cut along the fracture line.Mter the marrow cavity was reamed,a new irregular wound was created at sclerotic fracture ends.Scale-shaped chips (1 mm thin and 5 mm in diameter) were elevated using a chisel on surface of the cortical bone within 2 cm from the fracture ends.The external fixators were adjusted to compress the fracture sites.On the 8th day after operation,the eternal fixators were applied to distract and compress at nonunion sites to stimulate the osteogenesis.Results All the patients were followed up for an average of 12.5 months (range,from 8 to 42 months).Primary union was successfully achieved in 28 patients while delayed union occurred in 3 patients who finally achieved union after adjuvant therapies like shock wave and or local injection of bone marrow blood.The average time for union was 4.6 months(range,from 4 to 7 months).The mean time for external fixation was 6.2 months (range,from 5 to 8 months).One patient encountered nonunion of lateral tibial cortical bone 6 months after surgery but eventually achieved union by autologous ilium grafting.Joint functions in all postoperative patients were similar to those before operation.Conclusion Percutaneous osteoperiosteal decortication combined with distraction osteogenesis is a simple,minimally invasive and effective treatment for nonunion of lower-extremity bones,avoiding disadvantages brought by traditional surgery,like massive trauma and excessive bleeding.

Modification study of cyanoacrylate medical adhesive / 医疗卫生装备

Objective To perform modification study of cyanoacrylate (CA) medical adhesive and to select the optimal mo-difying material and the best ratio.Methods Carboxylic multi-walled carbon nanotubes (MWCNTs-COOH), multi-walled carbon nanotubes (MWCNTs), hydrophobic nano-silica, nitrile rubber, epoxy resin and polymethyl methacrylate (PMMA) were used to modify 5% triclosan/cyanoacrylate antimicrobial adhesive respectively. The bond strength, toughness and viscosity of the modified adhesive were examined in different concentrations.Results 0.064% MWCNTs-COOH, 6% nano-silica, 4% nitrile rubber and 6.4% epoxy resin all had good effects in strength modification. The bond strength were (14.71±1.48)MPa, (14.03±1.92)MPa, (14.6±1.78)MPa and (14.05±1.46)MPa respectively. 8% nano-silica had the lowest Tg of (1.1±0.24)℃ and the strongest viscosity of (15 536.68±28.4)cP. When the nano-silica concentration was 8%, the compound was very viscous and sticky. When the antimicrobial adhesive modified with 6% nano-silica, the bond strength was (14.03±1.92)MPa, the Tg was (3.6±0.68)℃, and the viscosity was (5 278.87±31.68)cP.Conclusion 6% nano-silica is the best modifying material, and has the optimal effect of modification.

Experimental study on new self and mutual-aiding occlusive dressing for wound / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Self and mutual-aiding occlusive dressing is a novel method to treat with the wounds in special circumstances. This study aims to prepare a new antimicrobial adhesive for the dressing and evaluate the application effects of the adhesive.</p><p><b>METHODS</b>The main component of the new antimicrobial adhesive was 5% triclosan / cyanoacrylate (CA) antimicrobial adhesive. The adhesive was modified with carboxylic multi-walled carbon nanotubes (MWCNTs-COOH), multi-walled carbon nanotubes (MWCNTs), hydrophobic nano-silica, nitrile rubber, epoxy resin and polymethyl methacrylate (PMMA) respectively. The bond strength, toughness and viscosity of the modified adhesive in different concentrations were examined to select the optimal modifying material and the best ratio to prepare the new antimicrobial adhesive according to the results. After that, the antimicrobial property of the new antimicrobial adhesive was tested by filter paper method. At last, we disposed the injury models in rats using the new antimicrobial adhesive to examine the application effects.</p><p><b>RESULTS</b>In individual tests, the bond strength modification performance of 0.064% MWCNTS-COOH is the best, the bond strength is (14.71 ± 1.48) Mpa. 8% nano-silica shows the best toughness modification performance, the Tg is (1.10 ± 0.24)°C. The viscosity modification performance of 8% nano-silica is the best, the viscosity is (15 536.68 ± 28.4) cP. However, consolidating three test results, 6% nano-silica/antimicrobial adhesive has the balanced bond strength, toughness and viscosity. Its bond strength is (14.03±1.92) Mpa, the Tg is (3.60 ± 0.68)°C, and the viscosity is (5 278.87 ± 31.68) cP. The inhibition zone diameter of 6% nano-silica/antimicrobial adhesive and antimicrobial adhesive group in Day 5 is (28.61 ± 0.91) mm versus (28.24 ± 2.69) mm (P > 0.05). In animal studies, both in blood routine test and pathological section, 6% nano-silica/antimicrobial adhesive group shows lower white blood cells count than gauze bandage group (P < 0.05).</p><p><b>CONCLUSIONS</b>6% nano-silica has the optimal effect of bond strength modification, toughness modification and viscosity modification, and the antimicrobial adhesive modified with it has a good antimicrobial property (resistant staphylococcus aureus).</p>

A novel method of defective vascular reconstruction using 2-octyl-cyanoacrylate and homemade prosthetic component / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Currently, adhesive technique is popular in vascular repair but not widely used for defective vessels. This study aimed to determine the feasibility and effectiveness of repairing defective vessels with 2-octyl-cyanoacrylate and a homemade prosthetic component.</p><p><b>METHODS</b>Homemade prosthetic component consisting of expanded polytetrofluoroethylene (ePTFE), terylene film, and homemade soluble hollow stent mixed with adhesive can replace autologous graft and suture in repairing defective vessels, can fix vessels better using the stent without occlusive bleeding. Forty male mongrel dogs were used, 20 for biomechanical tests and 20 for animal experiments. In the biomechanical test, dogs were randomly divided into two groups (n = 10 each), one group repaired on the two sides of the carotid arteries with 2-octyl-cyanoacrylate and homemade component and another group repaired with suture and ePTFE. Of the 40 specimens, 10 were used for adhesive and 10 for suture specimens for tension strength test, whereas the remaining specimens were used for bursting pressure test. In animal experiments, dogs were also divided into adhesive and suture groups (n = 10), only of the left carotid artery. Recording the operational time, bleeding or not. Vessels were tested using color Doppler ultrasound, the inner diameter was measured, and the degree of stenosis at 8 weeks was evaluated digital subtraction angiography (DSA) were also performed. Specimens were then analyzed histologically.</p><p><b>RESULTS</b>In the adhesive and suture groups, the specimens could afford atension strength of (23.80 ± 1.51) N versus (24.60 ± 1.08) N (P > 0.05), the bursting pressure was (52.03 ± 2.43) kPa versus (50.04 ± 3.51) kPa (P > 0.05), and the mean time of anastomosis was (15.20 ± 0.55) minutes versus (25.97 ± 0.58) minutes (P < 0.05). One dog in the adhesive group was bleeding from the suture. One dog from each group presented with thrombosis at 1 week. After measuring using ultrasound, the stenosis degree of all dogs were no more than 30% except the two thromboses. DSA and histological observation showed no obvious difference between the two groups.</p><p><b>CONCLUSION</b>Defective vascular anastomosis with 2-octyl-cyanoacrylate and our homemade prosthetic component is feasible, effective, timesaving, and easy to master.</p>

Control of hemorrhage during the operation of old pelvic fractures by temporary balloon occlusion of the common iliac artery / 中华骨科杂志

ObjectiveTo discuss the clinical application of the temporary balloon occlusion of the common iliac artery in the control of hemorrhage in the operations of the old pelvic fractures.Methods From January 2006 to June 2009,twelve patients (10 males,2 females; mean age 33.9 years) with old pelvic fractures of Tile C type were treated operatively.Three cases were treated with external fixator.Operative treatments were delayed for the treatment of the life-threatening visceral injuries in six nonunions and three malunions.A balloon catheter was placed through intravascular intervention in the common iliac artery of the affected side.The balloon catheter was infolded when the osteotomy was performed and the operations were undertaken under temporary and total occlusion of the common iliac artery.Osteotomies and internal fixations were performed in 12 cases.Decompressions of lumbosacral trunk were undertaken in 4 cases complicated with injuries of sciatic nerve.ResultsThe mean time of operations was 290 min(range,210-367min).The mean time of occlusions was 65 min (range,45-90 min).The loss of blood ranged from 700 ml to 2800 ml,with an average of 1833 ml.All cases were followed up for 12-48 months,with an average of 35 months.The mean time of bone healing was 20.6 weeks (range,16-24 weeks).No thrombosis of the common iliac artery and deep venous thrombosis of the lower extremity or ischemic necrosis happened.In the four cases complicated with injuries of sciatic nerve,three recovered partly and could walk with a crutch and one recovered completely and could walk normally.Two cases limped and other six cases could walk normally.ConclusionThe effect of temporary balloon catheter occlusion of common iliac artery is reliable.It drastically reduces hemorrhage during the operation and avoid the complications of selective arterial embolism and ligation and makes the operations of the old pelvic fractures more safer.

Treatment of non-infective nonunion with locking plates following surgery for long bone fractures / 中华创伤杂志

Objective To investigate the cause of fracture nonunion and discuss the experience of locking plates fixation combined with autoallergic cancellous bone in the management of non-infective long bone nonunion.Methods A retrospective analysis was made in 38 patients(29 males and 9 females)with fracture nonunion treated with locking plates fixation combined with autoallergic cancellous bone from August 2006 to August 2010.Of all,22 patients were treated with plates and 16 with interlocking intramedullary nails.Results All the patients were followed up for a mean of 12 months(range,6-24 months).The bone union time for all the fractures averaged 5.3 months(range,3-7 months),with no complications like implant loosening or fracture.Conclusions Iatrogenic factor is the main cause for fracture nonunion after open reduction and internal fixation of long bone fractures and the locking plates combined with autoallergic cancellous bone are a safe and effective treatment procedure.

Analysis of failure of transpedicular screw fixation for thoracolumbar fractures / 中华创伤杂志

Objective To discuss the causes of failure of transpedicular screw fixation in treatment of thoracolumbar fractures. Methods A retrospective analysis was done to analyze the failure causes of 24 patients (15 males and 9 females) who received pedicle screw fixation for their thoracolumbar fractures from June 2002 to June 2008 in our department. There were two patients with delayed infection, eight with pedicle screw breakage, one with connecting rod breakage, 10 with internal fixation loosening (including nut loosening) and three with poor screw position. Results All patients received reo-perations including removal of internal fixation plus debridement and lavage in two patients, simple removal of internal fixation in nine patients, removal of inter fixation and posterior fusion in two, replacement of the lengthened fixation plus posterior fusion in nine, and adjustment of the position and orientation of screw in two. All patients were followed up for 6-18 months (average 11 months) , which showed no any complications. Conclusion Improper surgical indication or approach, ineffective fusion, incorrect postoperative rehabilitation exercise, too late removal of the screws and improper surgical operation are main causes for failure of internal fixation.

Effect of Percutaneous Laser Disc Decompression on Phospholipase A2 and Nerve Conduction Velocity in Rabbit with Prolapse of Intervertebral Disc / 中国康复理论与实践

@#Objective To explore the mechanism of percutaneous laser disc decompression (PLDD) for treating prolapse of intervertebral disc. Methods 15 rabbits were divided into 3 groups randomly: sham group, model group with PLDD treatment, model group without PLDD treatment. The nerve conduction velocity (NCV) of L6 nerve root and the activity of phospholipase A2 (PLA2) in the intervertebral disc of L5-6 were determined 2 weeks after the initial surgery. Results NCV in the group with PLDD was significantly faster than that in the group without PLDD (P<0.001); NCV in the group without PLDD was significantly lower than that in the sham group (P<0.001). The activity of PLA2 in the group with PLDD was significantly lower than that in the group without PLDD (P<0.001); The activity of PLA2 in the group without PLDD was significantly higher than that in the sham group (P<0.001). Conclusion The activity of PLA2 in the herniated discs is higher than that in normal discs, which result in NCV falls remarkably. The PLDD can reduces chemical factors such as PLA2.

Clinical study of Osteoset~ synthetic bone transplants and internel fixations on calcaneus fracture / 中国矫形外科杂志

[Objective]To evaluate curative effects of Osteoset~ synthetic bone transplants and internel fixations on calcaneus fracture.[Method]Twenty-three patients with calcaneus fracture,who were treated by Osteoset~ synthetic bone transplants and internel fixation,were followed up by plain X-Rays and JOA functional questionnaires.Fracture patterns were based on Sanders methods.[Result]A series of 23 patients,7 of which were sanders Ⅱ,15 were sanders Ⅲ,3 were sanders Ⅳ,were treated with ORIF and Osteoset~ implants.The preoperative Blher's angle was 4.8 degrees(standard deviation 6.6 degrees).Blher's angle increased to a mean of 26.8 degrees(SD 8.6 degrees) postoperatively.In the first 3 months after surgery,a mean decrease in the Blher's angle of 0.4 degrees(SD 2.27 degrees) occurred.One month after surgery osteoset synthetic bone transplants,which was replaced by new bone,were gradually absorbed and degraded.JOA questionnaires suggested that the whole effective rate was 92 percent.[Conclusion]Osteoset synthetic bone transplants and internel fixations has good therapeutic effects on patients with comminuted calcaneus fracture.Osteoset~ synthetic bone has the same effects as autogenous bone.

Primary experimental study on a new sutureless vascular bonding method / 医疗卫生装备

Objective This paper is to study a new sutureless vascular bonding method. Methods New-Zealand rabbits were randomly assigned to one experimental group and one control group. 10 end-to-end bonding on rabbit femoral arteries (1.2mm vessel) were performed using the experimental technique with histoacryl glue (OB) and a central channel soluble stent. In the control group, 10 rabbit femoral arteries (1.2mm vessel) were anastomosed with the standard suture method. The patency rates and anastomotic time were recorded. The late anastomoses were evaluated with arteriograph and stoma tissue pathological section. Results The anastomosis mean time of the experimental group is 7.91 minutes and the one of the control group is 12.90 minutes. The immediate patency rates of two groups are both 100% and the late patency rates are 80% and 90% respectively. There are no haemorrhage when the clamp released and no distortion and stricture caused by sutures. Conclusion The sutureless vascular bonding method has no needs for suture needle and line, and thus the possible injuries during suture are reduced. The stent makes the vessel free from stoma stricture and binder invasion. The stoma leakage is also avoided through the adhensive. The enhanced suture speed results from the short clotting time and the hollow structure of the stent. With all the above-mentioned excellences, the method proves simple and efficient.

Study of Sealant Gels for Vascular Anastomosis with Adhesive, Cyanoacrylate Glue and Intravascular Soluble Hollow Stents / 医疗卫生装备

Objective To research and make one kind of sealant gel to prevent glue from leaking effectively,and protect vascular anastomosis site,raise the vascular anastomosis patency.Methods The experiment was carried out based on theory and methods in chemistry;According to the membrane performance,the membrane water solubility,and other characters,the author took experiment on the alginic acid sodium,chitsan,the gelatin and other biological materials.Results Through the experiment by membrane performance,the alginic acid sodium met the requirement,which became the membrane with the CaCl2 reaction at once.Its membrane was not dissolved in the water.And the characters of its 1%-3% solution were good on fluidity and surface contact angle determines.The biological compatibility of the compound of it with 20% CaCl2 solution was good.Conclusion The characters of the composition,which is double component sealant made from 1-3% alginic acid sodium and 20%CaCl2 solution,is best in the biological experiment.Before new medical glue appeared in clinical,this gel is hopeful to be applied in clinic and provide theory basis for clinical anastomosis.

Solution modes of intravascular stents for anastomosis / 医疗卫生装备

In this paper, the solution modes of two stents with different structures are compared, and then one involved is elected as the optimum stent for anastomosis. Made of PEG20 000, two stents are solid and hollow respectively. The result proves that the hollow one, with the advantages of nonblocking bloodstream, undeflected and rapid solution, low requirement for raw materials, is fitter for anastomosis than the solid one.

Twolayer structure of the hollow stent wall for bloodvessel anastomosis / 医疗卫生装备

A stent for bloodvessel anastomosis, with a slippery, soft out layer and a rapidly soluble inner layer, is developed in this paper. The out layer is made up of the gelatin with a high purity and a low molecular weight, and the inner one of polyglycol with a molecular weight of 20000. The structure changes of the stent surface are studied with anastomosis environment simulated. The result proves that the stent can be applied to bloodvessel anastomosis

Study of Model of Single Pedicle Separaration Flap / 医疗卫生装备

Objective To design a new flap model using for study on effects of some drugs which would maximize flap survival,and to evaluate its experimental availability.Methods The Wistar rat was used as the experimental animal.On the back of each rat,a skin flap,measuring 1.5 cm ? 6 cm,caudally based,was elevated and separated.Wound edges and the flap bed were separated from the flap by a silicone sheet and the drug was put in the areas between flap and sheet.On the seventh day after the flap elevation,historical and physiological measurement to blood flow and skin specimens would be done.The repeatability of the model was calculated.Results Single pedicle separaration flap needed 26 rats as samples when the resolution was 10% in testing,while the back flap model(10 cm ? 3 cm ) needed 28 rats.The needed samples were 2 rats and 5 rats respectively when the resolution was 25%.So it was believed that with high repeatability,the model of pedicle separation flap met the basic principle of testing design and was suitable for the study of the same kind.Conclusion The model can be used with confidence to study the effects of drugs on the flap survival.

Effects of Different Dose of VitC in Single Pedicle Separartion Flap Survival / 医疗卫生装备

Objective To study the effect of different dose of VitC in the flap survival.Methods The Wistar rat was used as the experimental animal.On the back of each rat,a skin flap,measuring 1.5cm?6cm,caudally based,was elevated and separated wound edges and the flap bed from the flap itself by a silicone sheet.The VitC 30mg/ml,120mg/ml,300mg/ml were taken in the areas between flap and sheet respectively.With 8 rats in each group,the VitC group was as trial group,while the physiological saline group was as control group.On the seventh day after the flap elevation,flap survival length measurement would be done.Results The flap survival length changed with the dose of VitC.When the dose of VitC was 120 mg/ml,the maximum length was got.When the dose of VitC amounted to 300 mg/ml,the flap will be necrotic.Conclusion The effect of VitC on flap is bidirectional: suitable dose can improve its survival in some way;the flap will be necrotic along with the increase of the dose.The clinical side effect of VitC in whole body toxic effect is often noticed,such as renal toxicity,while the partial side effect is often ignored.The experiment shows that large local dose of VitC will result in side effect.So the dose of VitC should be controlled to reduce side effect.

Effect of different drugs in single pedicle separation flap survival / 医疗卫生装备

Objective To study the effect of the VitC, bFGF, Magnesium sulfate and Papaverine in single pedicle separation flap survival. Methods The Wistar rats were used as the experimental animal. On the back of each rat, a skin flap, measuring 1.5 cm?6cm, caudally based, was elevated. Wound edges and the flap bed were separated from the flap itself by a silicone sheet. The VitC, bFGF, Magnesium sulfate and Papaverine were taken in the areas between flap and sheet. With 8 rats in each group, the drug-taken group was as trial group, while the physiological saline group was as control group. On the seventh day after the flap elevation, flap survival length was measured. Results The selected drugs could improve flap survival in some way, among which the effects of the VitC was the most distinct. Conclusion All the drugs can improve blood-flow, so it is believed the selected drugs can improve flap survival by improving flap’s blood-flow.