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This paper proposes an algorithm of building keypoint matches on multimodal images by combining a bootstrap process and global information. The correct ratio of keypoint matches built with descriptors is typically very low on multimodal images of large spectral difference. To identify correct matches, global information is utilized for evaluating keypoint matches and a bootstrap technique is employed to reduce the computational cost. A keypoint match determines a transformation T and a similarity metric between the reference and the transformed test image by T. The similarity metric encodes global information over entire images, and hence, a higher similarity indicates the match can bring more image content into alignment, implying it tends to be correct. Unfortunately, exhausting triplets/quadruples of matches for affine/projective transformation is computationally intractable, when the number of keypoints is large. To reduce the computational cost, a bootstrap technique is employed that starts from single matches for a translation and rotation model, and goes increasingly to quadruples of four matches for a projective model. The global information screens for "good" matches at each stage and the bootstrap strategy makes the screening process computationally feasible. Experimental results show that the proposed method can establish reliable keypoint matches on challenging multimodal images of strong multimodality.
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Objective Risk factor of radial and horizontal tear for posterior horn of medial meniscus is analyzed in present study.Methods A total of 390 patients diagnosed with medial meniscus tear received during January 2011 to December 2012 were of retrospective analysis.94 cases with radial tear of medial meniscus posterior horn and 95 horizontal cases were chosen as research objects.Age,gender,duration of symptoms,body weight index,trauma history,posterior slop of tibia plateau,knee valgus angle and Outerbridge cartilage classification of patients with radial or horizontal tear were recorded and analyzed.Multifactor unconditioned Logistic regression analysis was employed to analyze risk factor of meniscus radial tear.Results Significant difference could be spotted in the analysis of gender (x2=9.059,P=0.003),body weight index (t=2.549,P=0.012),knee valgus angle (t=-5.609,P=0.000) and Outerbridge cartilage classification (x2=42.300,P=0.000) between patients with radial or horizontal tear.Meanwhile,no significant difference could be spotted in the analysis of trauma history (x2=0.368,P=0.544),posterior slop of tibia plateau (x2=1.021,P=0.312),age (t=-1.228,P=0.221) and symptom duration (t=0.272,P=0.786).According to the results of multi-factor analysis,valgus angle (OR=12.581,P=0.001),age (OR=0.875,P=0.026) and Outerbridge cartilage classification (OR=33.790,P=0.000; OR=15.558,P=0.000; OR=39.891,P=0.000; OR=91.041,P=0.000) were risk factors of meniscus radial tear.Conclusion High incidence of posterior horn of medial meniscus tear was found in patients with senile osteoarthritis.The incidence of radial tear of medial meniscus posterior horn in elderly patients with knee varus or serious articular cartilage was higher than that of horizontal tear.
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BACKGROUND:Proximal humeral fracture fixation can provide a more stable fixation, has a stronger biomechanical stability, but open reduction and fixation wil cause extensive soft tissue dissection and heavy damage to the rotator cuff. Closed wear nail has a high failure rate of fixation, fracture re-displacement and other defects. OBJECTIVE:To investigate the technical methods of applying closed reduction, percutaneous pinning anatomical external fixation in repair of proximal humeral fracture, and to analyze the application characteristics and safety in different types of proximal humerus fractures. METHODS:Based on the special anatomical structure of proximal humerus, a shoulder external fixator has been independently researched and developed by author. The clinical data of 23 patients treated with closed reduction and percutaneous pinning anatomical external fixation (homemade) because of proximal humerus fracture at the Department of Traumatology, Tianjin Hospital during March 2010 to March 2014 were retrospectively analyzed. In accordance with Neer classification type, there were 19 cases of 2-part fractures of the humerus, 4 cases of 3-parts fractures of the humerus, with greater tuberosity avulsion fractures, which were al fresh fractures and were treated with closed reduction pinning and external fixation. Regular fol ow-up was conducted after treatment. Radiographic assessment, pain and function evaluation were conducted during fol ow-up, so as to work out the functional recovery, determine the final repair result. RESULTS AND CONCLUSION:Al patients were fol owed up for 6-24 months. Total y 23 patients initial y healed in fracture within 8 weeks. After treatment, visual analogue pain score of patients was 0.8 points. In the final fol ow-up, the American Shoulder and Elbow Surgery Association of shoulder function scoring system (ASES) score was an average of (91.7±2.6) points, Constant shoulder function score was an average of (88.3±4.7) points, the University of California (UCLA) shoulder joint scoring system score was (31.9±3.1) points, simple shoulder test (SST) system score was an average of (9.6±2.4) points. The shoulder function assessment (UCLA score) of these 12 patients was excel ent, of 9 cases was good, and of 2 cases was poor. The excel ent rate reached 91%after treatment. These results suggest that the application of closed reduction, percutaneous nailing anatomical external fixation in repair of proximal humerus fractures has the features of stable fixation, and smal damage of soft tissue. Standardizing the angle of closed nailing and entrance point, fixing from the intersection of three planes in arcuate-shape and connecting with external fixation can achieve a more stable fixed effects.
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Objective To investigate the clinical efficacy of arthroscopy with anchor treatment on acute patellar dislo?cation. Methods Retrospective analysis of patient with acute patellar dislocation cases who visited our hospital from March 2010 to June 2013 and were followed up for 10 months or more after being discharged. Patients all underwent physical exami?nation and imaging examination before operations. All operations were performed under arthroscopy. Joint hematoma were first drained, then articular cartilage injury were explored and repaired. Corresponding relationship between patella and femo?ral condyle were observed. After that, lateral retinaculum was released and medial patellofemoral ligament was repaired by suture anchors. Finally patellar reduction and its corresponding relationship with femur were observed after operation. Re?sults Medial patella cartilage injury and bone contusion of femoral condyle were all observed under arthroscopy. Medial patellofemoral ligament damage and tensed lateral patellar retinaculum were combined. By the time of follow-up at 10~18 months later, no dislocation was found and fear test are all positive. No recurrence of patellar dislocation was observed. Compared the conditions before operation and the last follow-up, Lysholm score(91.38±1.65 vs 60.04±3.93), Kujala score (90.62±2.08 vs 55.27±3.00),patellar camber angle(11.96°±1.43° vs 25.15°±2.13°)were all imporved(P<0.01). Conclu?sion Arthroscopy with suture anchors present good clinical effect in the treatment of acute patellar dislocation, which in?cludes alleviating keen pain, stabilizing joint instability and restoring knee stretching. It also present with less recurrence of patellar dislocation.
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In the elderly, patient who suffered from hip fracture need to stay in bed for a long time and has a higher prevalence of complications and mortality. Considering the factors of patients in the intraoperative death and postoperative re?habilitation, we take appropriate treatment measures during preoperative, intraoperative and postoperative period respective?ly based on the concept of Enhanced Recovery. Patient will benefit from rapid rehabilitation and reduction of incidence of complications and mortality. ERAS includes preoperative fasting, preventive anagelsia, intraoperative temperature control, anesthesia and surgical approach, postoperative intravenous restriction, nutritional support and painless early motion. This ar?ticle intends to review the security , reliability and clinic efficacy of ERAS.
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Objective To compare the stress distribution of calcaneal compression articular surface and normal surface in biomechanical analysis.Methods The posterior articular facet of the normal finite element model was wedged resected from inside to outside and from front to back,to imitate the malunion model with subtalar articular surface collapse after fracture.The B(o)hler angle was 35° before wedged,and 0° after wedged.On heel and Achilles tendon attachment point,320 N and 160 N loads were applied vertically upwards respectively.Compare calcaneal Vonmises stress distribution between malunion and normal model.Results Judging from the general stress distribution of malunion of calcaneal,subtalar joint stress reduced.The main stress area of normal bone joints was in articular surface,while the main stress area of malunion model was in the lateral calcaneal close to the calcaneocuboid joint.The main stress of the outboard is high-er than that of inboard.Outboard is the main part of supporting load.Judging from the detailed comparison with bone structure,first of all,the subsidence of subtalar joint top resulted in partial backward of the main stress of the calcaneus,which shifted to the Achilles tendon attachment point.It increased from normal (1.51±0.22) MPa to (3.11±0.24) MPa.Joint top of the stress reduced from normal (6.71±0.37) MPa to (2.83± 0.49) MPa.Secondly,the calcaneus stress of the former calcaneocuboid articulation significantly increased,which increased from normal (0.46±0.15) MPa to (2.13±0.15) MPa,and sustentaculum tali stress decreased from 5.18 MPa to 1.41 MPa.Conclusion By finite element model of this subject,the study proves that subtalar joint surface collapsed in calcaneal fractures is the main causes of most pathological changes.The problem of the joint surface subsidence should be resolved firstly in a clinical treatment,and the normal height of the calcaneus should be restored.The internal stress distribution of calcaneal is essential to the pain in the related part of calcaneal.
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Objective To investigate the influential factors for refracture of the adjacent vertebral body following percutaneous vertebroplasty (PVP) treatment of patients with osteoporotic vertebral compression fractures (OVCFs).Methods A retrospective analysis was conducted on OVCFs patients undergone mono-segmental PVP from July 2007 to March 2010.Patients' age,gender,bone density,bone cement infusion dosage,bone cement leakage and pre-and post-operative fracture reduction were documented.Kaplan-Meier remaining rate curve was used to predict the trend of time to refracture.The related factors for adjacent vertebral body refracture following PVP were analyzed.Results In all,216 patients (98 males and 118 females; age range of 55-76 years,average 65.4 years) were enrolled in this study.Follow-up lasted for 12-18 months.Ninety-two patients sustained refracture including 68 patients with refracture of the adjacent vertebral body.Refracture of the adjacent vertebral body presented time-concentrated tendency and 66% (45/68) occurred within 100 days followed by a notably lower incidence.Whereas the time to refracture of the non-adjacent vertebral body was not obviously centralized.Bone cement infusion dosage and vertebral body reset condition were strongly associated with the refracture incidence of the adjacent vertebral body,while opposite results were observed in regard of age,gender,bone density and bone cement leakage (or not).Conclusion PVP predisposes OVCFs patients to refracture of the adjacent vertebral body and its influential factors may be associated with bone cement infusion dosage and vertebral body reduction condition.
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Objective To build a three-dimension finite-element model of patella and to make a preliminary mechanics analysis on the model.Methods According to the model-building principle of Ansys software which started from point to line to area to volume,a three-dimension finite-element patella model was reconstructed on the basis of the images of spiral CT.Then,loading on the model patella were simulated and the stress magnitude and distribution on the patella were analyzed.Results Finite element analysis of the patella showed that stress concentration zone located in the middle and lower patella,indicating that fracturepredilectionsitesinthelower patellar.TheVon misesstresson thetensionsidewas significantly greater than that on pressure side.Conclusion The established finite element model of the patella can reflect the real geometry of patella treated in clinics.
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Objective To discuss external fixation method for the complex diaphyses fracture involving condyles of femur and evaluate its clinical efficacy.Methods A retrospective study was done on 42 patietns with comminuted femur diaphyses fracture combined with distal intra-articular fractures treated surgically from January 2001 to Janurary 2007.There were 24 males and 18 females at mean age of 33 years (20-66 years).According to AO/ASIF classification,there were 18 patients with type C2 fractures and 24 with type C3 ones.Simple internal fixation plus external fixation was performed on patitents with C3 fractures but only external fixation on those with C2 fractures.Four patients were treated with intramedular fixation.Results All patients were followed up for 1-12 months.According to Kotmert's assessment standard on function of proximal femur,the knee function was satisfactory in 35 patients (83% ) ,good in six (14% ) and unsatisfactory in one (2% ).Conclusions Minimally invasive external fixation can utmostly restore relative length of the femur and regulate between articular face of the femur and longitudinal axis of femur shaft to reach a symmetrical relation with middle and inferior part of opposite femur.Postoperative exercise is important for maximal recovery of the knee function.Attention should be paid to reconstruction of tubiform structure of the femur.
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BACKGROUND: Clinical observation demonstrates that accelerated fracture healing or lower limb heterotopic ossifications always occur in patients with paraplegia. It indicates that peripheral nervous system may play an important role in fracture healing process.OBJECTIVE: To observe bone histomorphometery parameter, callus formation and biochemical change during the process of fracture healing of unilateral lower limb denervated tibia.DESIGN: Self-control animal experiment.SETTING: Tianjin Hospital.MATERIALS: Totally 36 six-month-old healthy male Wistar rats, with mean body mass of 210 g, were used in this experiment.METHODS: This experiment was carried out at Animal Experimental Center of Tianjin Hospital from March 2001 to March 2004. Denervated tibia fracture model and innervated tibia fracture model were made in the same rat. Animals were executed under anaesthetic status at week 2 and week 4 after fracture. Bilateral tibias were chosen to take radiografts.Biomachamical strength was measured and non-decalcification sections were prepared to perform bone histomorphometery observation.MAIN OUTCOME MEASURES: ① Comparison of wet weight of bilateral tibias and callus of rats between two groups after fracture. ②X-ray plain film scoring. ③ Biomechanical testing of tibial samples. ④ Histomorphological observation of fracture healing RESULTS: ① Wet weight of bilateral tibia and callus of rats in denervated group was much higher than that in innervated group at weeks 2 and 4 after fracture [(0.94±0.15) vs (0.76±0.14) g, (1.06±0.26)vs (0.81±0.10) g,P < 0.05]. ②In X-ray plain film scoring, callus formation was significantly increased in denervated group (P < 0.01). ③In biomechanical testing of three-point bending of tibial sample, callus intensity was significantly lower at weeks 2 and 4 after fracture in denervated group than in innervated group[ (9.88±8.49)vs ( 16.62±13.38 ) N, ( 12.77±7.55 )vs (20.19±10.60) N,P < 0.05]. ④Bone histomorphometery showed that compared with innervated group, mineralized bone trabecula width of denervated group was significantly reduced (P < 0.05), osteoid width was increased , osteoclast index and bone absorption area were significantly increased (P < 0.05), and there were no significant difference of fibroblast index and bone formation area between two groups; Compared with innervated group, mineralized deposition rate in the denervated group was significantly reduced (P < 0.05), the mature time of osteoid was elongated (P < 0.05).CONCLUSION: Peripheral nervous system may play an important role during early and middle period of fracture healing. Intact innervation is essential for normal fracture healing.
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[Objective]To develop a mini-pressure-sensor(MPS)for measurement of plantar pressure(PP)and to evaluate its clinical application.[Method]The MPS was installed in the shoes,and computer was used to accumulate and analyze the change of PP in whole walking stage.Pathologic changes of PP in clinical patients were also analyzed by MPS.[Result]In normal walking,the PP of forefoot was 49% of body weight(BW)and of midfoot and heel was totally 51% of BW,but at pathologic state,the equilibrium of walking was dynamically disrapted inducing a pathologic changes of foot bearing.[Conclusion]Self-developed MPS for measuring PP is help for dynamic analysis of normal PP and is valuable to recognize the pathologic distribution of PP in pathological state and to provide a guide for treatment.
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[Objective]To investigate the treatment of nonunion after Pilon fracture with fibula approach fixation of tibia and ankle joint fixation and its clinical efficacy.[Method]Six cases of nonunion after Pilon fracture were collected from 1999 to 2004,which included 4 males and 2 females,with the average age of 34.7 years(21~53 years).All fractures were found invasion to the tibia-fibula joint and ankle malformation.Fibula and tibia were opened from posterolateral approach and reconstruction plate was placed laterally on the fibula,with screws crossing the fibula into the tibia directly.Autogenous bone graft was used in fracture position and area between tibia and fibula to gain tibia-fibula fusion.[Result]All cases were followed up from 8 months to 4 years with the average of 22 months.Bone fusion were gained in 5 cases with the average time of 3.5 months.Plate broken was found in 1 case for too early weight bearing.[Conclusion]Fibula approach fixation of tibia and ankle joint fixation has advantages of promoting fracture healing,preventing complications,and correction joint malformation.It is a convenient and reliable method for clinical surgeons.
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[Objective]To summarize the experience about treatment of segmental and comminuted femoral fractures with intramedullary nail in multiple injuries.[Method]From March 2002 to July 2006,28 patients with segmental and comminuted femoral fractures were treated surgically,13 with AO type C1,9 with C2 and 6 with C3.All of the fractures were treated with close reduction static intramedullary nail fixation.[Result]The postoperative follow-up ranged from 11 to 34 months with an average of 21 months.All of the fractures were healed.Limit load was required for 5 patients who had delayed union without special treatment.After 18-30 months the patients healed up.There were no fat embolisms.No complications such as infection,intramedullary bending or break occurred.[Conclusion]Treatment of femoral fractures with intramedullary nail is a standard method.However,to achieve satisfactory results,comprehensive treatment,careful planning and procedure should be taken for segmental and comminuted femoral fractures in multiple injuries.
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The characteristics and purpose of treatment of tibiofibular comminuted fracture is reviewed in this paper.The present points of view is that tibiofibular comminuted fracture is a kind of smash fracture,that is valuable for restoring its tubular structures.The appearance of a series of new type plates and external fixations represents the trend of researching.The combination of internal/external-fixation and sequential treatment is waited for more research.
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Literatures about patella fracture fixation in recent years are analyzed retrospectively in this paper.Its characteristics and therapeutic purpose are investigated.A series of new type of internal fixations and external fixations are emphasized.
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Objective To study the effects of peripheral nervous system on early and middle periods of fracture healing. Methods Denervated tibia fracture model and innervated tibia fracture model were made at the same rat. The animals were executed at day 15 and day 30 after operation respectively. Callus sizes were evaluated by radiograph. The mechanical properties of calluses were recorded in a three point bending test. The callus microstructures were measured by bone histomorphometry.Results Radiograph showed an increased callus formation in the denervated group both on day 15 and day 30 after operation (P0.05). Compared with the innervated groups, 30 days dynamic parameters indicated that mineral appositional rates of the denervated sides significantly decreased (P