THE SYNTHESIS AND CHARACTERIZATION OFPOLY-L-LACTIDE USED FOR THE INTERNALFIXATION OF BONE FRACTURE

A high Mw of PLLA was synthesized, it intended to be used in the manufacture ofbioabsorbable screw applied in bone fracture internal fixation. The optical reactionconditions have been discussed.

MIPPO technique and LCP internal fixation for open tibial shaft fractures

Objective To explore the efficacy of minimally invasive percutaneous plate osteosynthesis (MIPPO) technique and locking compression plate (LCP) for open tibial shaft fractures.Methods From March 2005 to May 2009,16 cases with open tibial

Association between anterior internal fixation systems and post-operative lateral angulation in thoracolumbar fractures

Objective To explore the effects of the anterior internal fixation systems on the post-operative lateral angulation in treatment of thoracolumbar fractures.Methods A retrospective study was done to analyze the 172 patients who had

Percutaneous reduction combined with bone graft in treatment of displaced intra-articular calcaneal fractures

Objective： To introduce the experience and key points of percutaneous reduction combined with bone graft to treat calcaneal fractures. Methods： Percutaneous reduction and internal fixation combined with bone graft was performed from April 2004 to April 2006 on 15 cases （16 sides） with intra-articular calcaneal fractures including 13 males （14 feet） and 2 females （2 feet） ,with average age of 36. 6 years （24-61 years）. All patients underwent radiography including lateral and axial views for calcaneus, oblique view for foot and three-dimensional CT imaging reconstruction. According to Sanders classification, there were 12 feet of type Ⅱ （3 type Ⅱa, 3 type Ⅱb and 8 type Ⅱc） and 2 feet of type Illac. The length of calcaneus was recovered through traction by Steinmann pin which passed through calcaneal tubercle perpendicularly and the posterior facet was elevated until reduction by a curve scissors through an 0.5 cm incision along the primary fracture line of lateral calcaneus. The calcaneus was fixed with different cannulated cancellous screws according to the type of fractures. Then bone graft was injected to fill the defect of calcaneus through lateral incision. Results： All patients were followed up for an average of 18.4 months （ranged, 12 to 34 months）. No complication such as wound infection, screw breakage and calcaneum varus was found postoperatively. The average time for bone healing was 10 weeks. The results were excellent in 12 cases, good in 4 cases according to the American Orthopaedic Foot and Ankle Society （AOFAS） hindfoot score. The rate of excellent and good clinical results was 100%. The mean AOFAS hindfoot score in tongue type group （86.5±4.4） was better than in joint depression type group （81.2±1.7, P〈0.05）. Radiography showed basic restoration of Bohler＇s angle, Gissane＇s angle and calcaneal shape. Conclusion： The combination of percutaneous reduction and injectable bone graft is suitable for surgical treatment of Sanders Ⅱ and Ⅲ type calcaneal fractures, with advantages of simple operation, fewer complications and good clinical results.

Comparative Dimensional and Microscopic Analysis of the Strength and Hardness of Internal Fixation Plates

The fixation stability achieved with the use of plates and screws in oral and maxillofacial surgery is a decisive factor in treatment success. The mechanical and structural properties of the internal fixation materials have direct influence on the dimensional stability and resistance of a fixation system, thus influencing treatment outcomes. This study proposed to analyze the dimensional and resistance patterns of titanium plates used for obtaining stable fixation in orthognathic surgery and craniofacial trauma. For this study, 30 conventional 2.0 mm straight four hole plates with bridge from three brands commercialized in Brazil, were subjected to macroscopic, microscopic, strength and hardness analysis. The dimensional measurements were performed using a digital caliper. Energy-dispersive X-ray spectroscopy analysis was performed by scanning electron microscopy to analyze the chemical composition of the samples. The mechanical resistance tests were performed with a universal testing machine. The samples were then submitted to Vickers hardness analysis, complying with the standards of ASTM E92. The data collected from the dimensional study was submitted to statistical analysis of the coefficient of variation, while the values obtained during the mechanical tests were analyzed by variance (ANOVA) and Tukey’s test (p < 0.05). The sample groups presented different performances in resistance, hardness, size and surface, even though they were reported to be chemically similar compounds that allowed us to conclude the plates from Group 2 were more resistant than groups 1 and 3.

HIGH CYCLE FATIGUE PROPERTIES OF NICKEL-BASE ALLOY 718

The fatigue properties of nickel-base Alloy 718 with fine- and grain-coarse grains were investigated. In the fine-grain alloy, the fatigue strength normalized by the tensile strength was 0.51 at 107 cycles. In contrast, the fatigue strength of the coarse-grain alloy was 0.32 at the same cycles, although the fatigue strengths in the range from 103 to 105 cycles are the same for both alloys. The fracture appearances fatigued at around 106 cycles showed internal fractures originating from the flat facets of austenite grains for both alloys. The difference in fatigue strength at 107 cycles between the fine- and coarse-grain alloys could be explained in terms of the sizes of the facets from which the fractures originated.

Open reduction and internal fixation for displaced supracondylar fractures of the humerus in children with crossed K-wires via lateral approach

Objective： To assess the therapeutic results of open reduction and internal fixation with crossed K-wires via lateral approach for displaced supracondvlar fractures of the humerus in children. Methods： We prospectively followed 52 children who presented with Gartland type 3 displaced supraeondylar fractures of the humerus and were managed by open reduction and internal fixation with crossed K-wires via lateral approach.There were 37 male and 15 female patients; average age was 7.39 years. The most common mechanism of trauma was fall while playing （n=23）, followed by fall from height （n=20）, road traffic accidents （n-5） and fall from standing height （n=2）. In 2 cases, mode of injury was not available. The mean follow-up was 12 months and patients were assessed according to Flynn＇s criteria. Results： Lateral approach provided an excellent view of the lateral column between two nervous planes and enabled an anatomical reduction in all cases. Immobilizing the elbow at 90 degrees or more of flexion was not needed after cross K-wire fixation. Majority of patients regained full range of motion within 6 weeks of pin removal. Two patients had postoperative ulnar nerve injuries that resolved after pin removal. The common late complication of cubitus varus was not seen in any patient. Delayed presentation to the emergency department, repeated manipulations by bone setters and massage with edible oil were responsible for stiffness in 5 patients. Superficial pin tract infection was noted in 5 patients that resolved with dressings and antibiotics. No deep infection occurred. A detailed clinical examination and radiographic analysis was done at final follow-up. They included measurement of carrying angle and range of movements of both operated and normal sides, and radiographs of both upper limbs for comparison. According to Flynn＇s criteria, 90.4% patients showed satisfactory results. Conclusion： Lateral approach for open reduction and internal fixation of the widely-displaced supracondylar fracture of the humerus is safe and straightforward, ensuring anatomical reduction and excellent function. The approach is easy and familiar to most orthopedic surgeons in our setup.

Closed reduction and internal fixation versus total hip arthroplasty for displaced femoral neck fracture

Objective： To compare the clinical effects between closed reduction and internal fixation （CRIF） and total hip arthroplasty （THA） for displaced femoral neck fracture. Methods： In this prospective randomized study, 285 patients aged above 65 years with hip fractures （Garden III or IV） were included from January 2001 to December 2005. The cases were randomly allocated to either the CRIF group or THA group. Patients with pathological fractures （bone tumors or metabolic bone disease）, preoperative avascular necrosis of the femoral head, osteoarthritis, rheumatoid arthritis, hemiplegia, long-term bed rest and complications affecting hip functions were excluded. Results： During the had significantly higher 5-year follow-up, CRIF group rates of complication in hipjoint, general complication and reoperation than THA group （38.3% vs. 12.7%, P〈0.01; 45.3% vs. 21.7%, P〈0.01; 33.6% vs. 10.2%, P〈0.05 respectively）. There was no difference in mortality between the two groups. Postoperative function of the hip joint in THA group recovered favorably with higher Harris scores. Conclusion： For displaced fractures of the femoral neck in elderly patients, THA can achieve a lower rate of complication and reoperation, as well as better postoperative recovery of hip joint function compared with CRIF.

Outcome of open reduction and internal fixation of intraarticular calcaneal fracture fixed with locking cal- caneal plate

Objective：Debate continues regarding the management of calcaneal fractures,between open reduction and internal fixation and closed treatment.Hence we aim at evaluating the radiological and functional outcomes of open reduction and internal fixation in displaced joint depression type of calcaneal fractures fixed with locking calcaneal plate.Methods：In this series,28 patients （26 unilateral and 2 bilateral） with joint depression type of calcaneal fractures as per Essex-Lopresti classification system were operated on with locking calcaneal plate within 3 weeks of injury.Patients were evaluated in terms of associated injuries and X-rays of anteroposterior,lateral and axial views of the calcaneum.CT scan was done to assess the amount ofcomminution and articular depression.Patients were followed up clinically and radiologically at least for 1 year.Radiological assessment was done by Bohler＇s angle and Gissane＇s angle along with measurement ofcalcaneal height and width.Functional outcome was assessed using the American Orthopaedics Foot and Ankle Society （AOFAS） scale.Results：At average follow-up of 14.5 months,average AOFAS score was 86.3 （range 66 to 97）,with 86% having excellent to good results and 2 （7.7%） and 1 （3.7%） having fair and poor results respectively.All patients had stable ankle joint with all having dorsiflexion and plantar flexion more than 30°.Average subtalar range of motion was 17°.The mean Bohler＇s angle,mean Gissane＇s angle,calcaneal height and width were 25.47°,121.3°,4.32 cm and 3.81cm respectively at final follow-up.Three patients had flap necrosis at incision site and one had superficial and deep infection.Subtalar arthritis was seen in 5 patients,whereas sural nerve hypoaesthesia in 1 patient.None of the patients had compartment syndrome,heel pad problems,peroneal tendinitis,reflex sympathetic dystropy or implant failure.Conclusion：Open reduction and internal fixation with locking calcaneal plate gives sound functional outcome,i.e.restoring anatomically reconstruction of height,width,Bohler＇s and Gissiane＇s angles of the calcaneum,and allowing early mobilization.

Clinical effect of distal radius fracture treated with open reduction and internal plate fixation

Background For some specific comminuted unstable intra-articular fracture,the plaster cast can not maintain the alignment of the articular surface effectively.The aim of this study was to evaluate the clinical effects of distal radius fracture treated with open reduction and internal plate fixation retrospectively.Methods From January 2002 to March 2010,539 cases of distal radius fracture were treated with open reduction and internal fixation,including 184 males and 355 females aging 21-72 years （mean 57 years）.Fractures were caused by falling to the ground in 459 cases,by traffic accident in 62 cases and by athletic injuries in 18 cases.Of 539 cases,there were 523 cases of closed fracture and 16 cases of open fracture.According to Arbeitsgemeinschaft fur Osteosynthesefragen （AO） standards of classification,there were 14 cases of A2 type,22 of A3 type,18 of B1 type,24 of B2 type,62 of B3 type,91 of C1 type,162 of C2 type and 146 of C3 type.The time from injury to operation was 1-16 days （mean 5 days）.All patitents received open reduction and internal plate screw fixation.Forty-seven patients with bone defect were given 6-15 g autologous ilium and 75 cases were given 5 ml calcium sulphate artificial aggregate after reduction.Results All incisions healed by first intention after operation.Patients were followed up for 15 to 32 months postoperatively （mean 22 months）.The fractures healed within 10-18 weeks after operation （mean 12 weeks）.During the last follow-up,the mean palmar tilt was （7.0±0.9）° and the mean ulnar variance was （21.0±4.2）°,showing significant difference when compared with preoperation （（-5.0±1.2）° and （8.0±3.8）°）.The radial heights were not abbreviated.According to Gartland and Werley assessment system,the results were excellent in 314 cases,good in 163 cases,fair in 46 cases,and poor in 16 cases 12 weeks after operation,the excellent and good rate was 88.5%.Conclusions The clinical effect of distal radius fracture treated with open reduction and internal plate fixation was relatively satisfactory.Meticulous operation procedure and individual rehabilitation strategy contribute to the wrist joint functional recovery.

Internal fixation with headless compression screws and back buttress plate for treatment of old Hoffa fracture

Objective： To analyze the early clinical and radiographic outcomes of Hoffa fractures treated by a standard protocol of open reduction and internal fixation using headless compression screws combined with back buttress plate in a consecutive series of 8 Chinese patients. Methods： Open reduction and internal fixation was performed on all patients. The fractures were anatomical- ly reduced and held temporarily by K-wire. If the ends of fractures were atrophic, autologous bone graft from the ipsilateral iliac crest was packed between the ends. Then the fracture fragments were fixed with AO 6.5 mm headless compression cannulated screws. At least two screws were used to provide rotational stability. One pre-contoured reconstruction plate was placed on the nonarticular surface posteromedially or posterolaterally as back buttress plate. Results： All the patients were followed up for at least 12 months （range 12-25 months）. All fractures achieved anatomical reduction and healed clinically and radiographically. At recent follow-up, the mean flexion degree was 120.6° （range 110°-135°） and the mean extension degree was 2.5° （range 0°-5°）. The average visual analogue scale score was 1.6 points （range 0-3）. Six patients were assessed as excellent and 2 as good according to the hospital for special surgery knee score system. There were no superficial or deep infections, or hardware breakages. No patient had giving way or locking of the knee, though some had intermittent pain and swelling after strenuous exercise. Injury mechanism had significant influence on the functional outcome （P=0.046）. Conclusion： Headless compression screws combined with back buttress plate and/or autologous bone grafting to treat old Hoffa fracture is one of effective measures. It would be conducive to not only fracture healing but also early exercise and functional recovery.

Classification to guide internal fixation for tibial fracture

Objective： To explore a classification method which can provide the clinical guidance for internal fixation of tibial fracture. Methods： The different fractures were fixed according to their mechanical classification. Totally, 71 cases of tibial plateau fracture, tibial proximal fracture, tibial distal fracture and Pilon fracture were analyzed to test this selective principle. Results： All 71 patients were followed up for 6-32 months. The displacement was seldomly observed in cases treated acccording to the classification principle, while some cases against the principle had postoperative displacement.The difference was statistically significant （P〈0.05）. It was proved that there was remarkable correlation between tibial fracture classification, internal fixator and fixation methods. Conclusion： Types Ⅲa3, Ⅲb 1 and Ⅲb2 fractures without eccentric moment should be fixed with double plates or angle-stable materials combined with locking structure, otherwise displacement may occur.

Use of gentamicin-loaded collagen sponge in internal fixation of open fractures

Objective： To assess the outcome of immediate plate osteosynthesis via application of antibiotic impregnated collagen fleeces （gentamicin-collagen and an- tibiotic sponge） which gradually release antibiotic locally in the surgical treatment of open fractures presented to us 6 hours after injury. Methods： All cases were treated in our tertiary level trauma center and teaching hospital including 35 patients with open fractures who were treated by immediate open reduction and plate fixation from January 2008 to August 2010. Among them, 31 patients were available for adequate follow-up and assessment. All fractures were treated by irri- gation and debridement, immediate open reduction and plate fixation along with placement of antibiotic-releasing collagen fleeces around the plate just before closure of wound. Pa- tients were assessed to determine postoperative infection, delayed union or nonunion and development of other post- operative complications. It was hypothesized that immedi- ate plate osteosynthesis after thorough debridement and local antibiotics would give safe and acceptable clinical results in treatment of open fractures. Results： The 31 patients with adequate final follow-up were assessed at a mean time of 40 weeks （15-160 weeks）.Most fractures united primarily in an acceptable time period according to area of involvement. Local wound complica- tions （superficial infection and skin loss） were found in 3 patients （9.67%）. Deep infection was noted in 2 patients （6.45%）. None of these patients needed implant removal and both fractures united in due time. Delayed union was noted in 5 patients （16.13%）. No patient progressed to non- union or implant failure in long term follow-up. Excessive scarring was developed in 2 patients （6.45%）. Conclusions： Immediate plate osteosynthesis after adequate debridement and placement of collagen film eluting antibiotics locally produces excellent results regarding bone union and absence of deep infections and is a safe technique in the management of open bone injuries. These sponges can be used easily with any form of internal fixa- tion and there is no need of second surgery for the removal of these antibiotic carriers since they are bioabsorbable. Local antibiotic-impregnated collagen sponges along with systemic antibiotics for 3 to 5 days offer promising results in open fracture management.

Timing of internal fixation and effect on Schatzker IV-VI tibial plateau fractures

Objective： To study the effect of internal fixation performed at different times on therapeutic outcomes of Schatzker IV-VI tibial plateau fractureS. Methods： The clinical data of 42 cases ofSehatzker IV- VI tibial plateau fractures treated in our department were analyzed retrospectively. Among these 42 patients, 21 re- ceived surgical treatment within 12 h after injury, （Group I）, the other 2 [ were first treated by traction or piaster fixation followed by a delayed internal fixation after soft tissue swell- i ing subsided （Group II）. The surgical time, comPlications, length of hospital stay, cost of hospitalization, and time for i fracture union, as well as functional recovery were analyzed and compared between the two groups. Results： After 10-28 months follow-up （mean 16.5 months）, except 5 cases who lost to follow-upl no differ-ences were found between the two groups regarding surgi- cal time, preoperative and postoperative complications, heal- ing time or the Hospital for Special Surgery （HSS） score at the end of follow-up, but significant differences were found in the length of hospital stay, cost of hospitalization and HSS score at 3 months after operation （P〈0.05）. Conclusion： Under certain conditions, early internal fixation for Schatzker IV-VI tibial plateau fracture is feasible, which can shorten the length of hospital stay, decrease the cost of hospitalization and promote early functional rehabilitation.

Bilateral traumatic proximal humerus fractures managed by open reduction and internal fixation with locked plates

Fractures of the proximal humerus are uncommon in young patients.Although bilateral fracture of proximal humerus itself is rare,association with epilepsy and electrocution is frequent.Only one case of traumatic bilateral proximal humerus fracture has been reported in the literature.We report a rare case of bilateral traumatic displaced proximal humerus fractures in a 40 years old male patient,which was treated by means of open reduction and internal fixation with proximal humerus locked pates on both sides and obtained a good functional outcome.

QualiW of life following total hip arthroplasW in patients with acetabular fractures, previously managed by open reduction and internal fixation

Purpose： Total hip replacement （THR） is one of the most successful and cost-effective surgical procedures and remains the treatment of choice for long-term pain relief and restoration of function for patients with diseased or damaged hips. Acetabular fractures managed either conservatively or operatively by fixation tend to present later with secondary joint changes that require THR. In this study we evaluated the functional outcome and quality of life achieved by such patients. Methods： Our study was carried out as a retrospective trial by recruiting patients who underwent THR from June 2006 to May 2012. A total of 32 patients were included with a mean age of 46.08 years ranging from （25-65） years. We evaluated the quality of life in the patients using scoring techniques of Short Musculoskeletal Functional Assessment （SMFA） and the 12-1tem Short Form Health Survey （SF-12）. Functional outcome was assessed using Harris Hip Score （HHS）. Results： The mean HHS of the patients was 84.3 with a range from 56 to 100. The SMFA averaged 13.3. The SF-12 score averaged 49.1. The correlation of the HHS with SF-12 was positive （p - 0.001 ） while with SMFA there was a negative correlation （p - 0.001 ）. Conclusion： From this study it is inferred that the functional outcome of THR and quality of life in pa- tients who had acetabular fractures and were initially managed by open reduction and internal fixation is good.

Subciliary incision and lateral cantholysis in rigid internal fixation of zygomatic complex fractures

Objective: To introduce the technique of subciliary incision and lateral cantholysis with tri-dimension reduction and rigid internal fixation to treat zygomatic complex fractures. Methods: The subciliary incision and lateral cantholysis combined with tri-dimension reduction and rigid internal fixation of zygomatic complex fractures with titanium microplates were applied in 56 patients with zygomatic complex fractures. Another lateral eyebrow incision or sublabial incision was used to simplify the operation. Results: The postoperative follow-up period ranged from 6 months to 5 years. During the follow-up period, all the patients had satisfying postoperative results. All clinical symptoms disappeared except the numbness in the infraorbital region in 2 patients. In 94.6% patients no complications such as obvious scar, ectropion, entropion or blepharoedema were found, only 5.4% of the patients had slight ectropion 6 months after operation. Conclusions: The subciliary incision and lateral cantholysis have many advantages such as invisible scar, sufficient exposure, minimal injury, and few complications and combined with rigid internal fixation with titanium microplates this technique could be used as one of the routine operation methods to treat zygomatic complex fractures.

Treatment of displaced radial head fractures by internal fixation with absorbable pins

Objective： To study the effect of internal fixation with absorbable pins on treatment of displaced radial head fractures. Methods： From May 1999 to May 2004, 16 patients with displaced radial head fractures （Mason types Ⅱ and Ⅲ） were treated with internal fixation by absorbable pins. The duration of follow-up averaged 22.6 months （12-58 months）. The outcome was assessed on the basis of elbow motion, radiographic findings and the functional rating score delineated by Broberg and Morrey. Results： All fractures healed within 10 months without avascular necrosis of radial head. The mean elbow flexion loss was 15°（0°-35°） , and pronation and supination decreased by 10°（ 0°-30°） on average compared with those of the contralateral elbow. Five patients had an excellent result, 6 a good result, and 3 a fair result according to the criteria of Borberg and Morrey. Conclusions： Internal fixation with absorbable pins is an effective method in treating displaced radial head fractures. It can maintain the biomechanical stability of forearm, improve the elbow function and avoid second operation.

A novel method of removal of a broken drill bit in the femoral medullary canal during internal fixation of a type C distal femoral fracture： a case report

Breakage of surgical instruments and implants during operative procedures is not uncommon in any surgical discipline. The need for removal and the out come of leaving the broken instruments and implants in the surgical area have not been described in detail. Few studies have suggested removal if they are lying loosely in the tis sues or joint, close to neurovascular structures. Challenges and the amount of time spent in the retrieval of broken instruments and implants are well most choose to leave them in known among surgeons, so situ. We reported a novel method of retrieval of a broken drill bit in the femoral medul lary canal during internal fixation of a type C distal femoral fracture.