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Objective:To explore mechanical stability of Proximal Humeral Internal Locking Plate System (PHILOS) in the treatment of Vancouver B1 femoral periprosthetic fractures by three-dimensional finite element analysis.Methods:A three-dimensional finite element model of the femur was established by digital medical software (Mimics 21.0, 3-matic12.0, Geomagic12.0 and Hypermesh 2017.0) using the CT data of a femur from a volunteer (male, 34 years old, 173 cm in height and 65 kg in weight). After the femoral trochanter was cut in the femoral models, a femoral stem was implanted. PHILOS fixation (PHILOS group) and Cable-Ready GTR fixation (Cable group) were applied respectively. Loads of 700 N, 1,400 N and 2,100 N were applied to the 2 groups of finite element models. Distributions of Von Mises stress and deformation were investigated in the finite element models of 2 internal fixations; the mechanical stability was compared between the 2 groups of models.Results:The maximum deformation occurred on the femoral ball head in the 2 groups of models. At the load of 2,100 N, the maximum deformation was 3.77 mm in the PHILOS group, larger than 3.58 mm in the Cable group, and the maximum stress peak value in the PHILOS group was 491.54 MPa, about 49.2% lower than that in the Cable group (733.61 MPa). The peak stress in the PHILOS group was mainly distributed on the 4th and 5th fixation ends at the bone plate while the peak stress in the Cable group was mainly distributed on the second titanium cable under the fracture line.Conclusions:Under various loads, both PHILOS fixation and Cable-Ready GTR fixation can provide sufficient mechanical stability. As the peak stress of PHILOS fixation is much lower than that of Cable-Ready GTR fixation, PHILOS can be used as an effective fixation method for Vancouver B1 femoral periprosthetic fractures.
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Objective:To evaluate the clinical efficacy of high tibial osteotomy(HTO) plus arthroscopic surgery in the treatment of medial gonarthrosis.Methods:From January 2017 to May 2018, 40 patients were treated at Department of Joint Orthopaedics, Wujin Hospital Affiliated to Jiangsu University and at Department of Joint Orthopaedics, The First Affiliated Hospital to China Medical University for medial gonarthrosis. They were divided into 2 groups according to their different treatment methods. Group A was treated by HTO plus arthroscopic surgery; there were 20 cases, 8 males and 12 females with an age of 59.7 years ± 5.5 years. Group B was treated by only HTO; there were also 20 cases, 10 males and 10 females with an age of 58.2 years ± 4.3 years. The 2 groups were compared in terms of Hospital for Special Surgery (HSS) knee score, visual analogue scale (VAS), hip knee ankle angle (HKA), medial proximal tibia angle (MPTA) and posterior tibial slope angle (PTSA) at 6, 12 and 24 months postoperatively and at the last follow-up.Results:The 2 groups were comparable because there were no significant differences between them in the preoperative general data ( P>0.05). The HSS and VAS scores at 6 months after operation in group A (82.7±2.4 and 1.7±0.7) were significantly better than those in group B (78.4±2.6 and 2.2±0.8) ( P<0.05); the HSS score at 12 months after operation in group A (88.1±1.8) was significantly better than that in group B (82.9±1.7) ( P<0.05). There were no significant differences between the 2 group in the VAS score at 12 months after operation, or in the HSS or VAS scores at 24 months or at the last follow-up ( P>0.05). There were no significant differences either in the HKA, MPTA or PTSA scores between postoperative 6, 12, 24 months and the last follow-up ( P>0.05). Conclusion:In the treatment of medial gonarthrosis, high tibial osteotomy plus arthroscopic surgery may lead to better short-term outcomes than high tibial osteotomy alone, but the 2 methods may result in similar curative efficacy by 24 months after surgery.
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Objective To evaluate the effect of posteromedial combined with lateral surgical approach in treatment of trimalleolar factures.Methods The clinical data of 37 patients with trimalleolar factures underwent open reduction and internal fixation through posteromedial combined with lateral surgical approach were retrospectively ana-lyzed.There were 21 males and 16 females with average age of 55.0 years (ranged 35 -80).Complications such as infection,nonunion,fixation failures were observed.All patients were followed up at 6 months and 12 months after sur-gery and assessed functionally with American Orthopaedic Foot and Ankle Society Scores (AOFAS).After the 12 month follow up,the patients were also called for a radiological examination.Results Average follow -up time was 18.8 months (12 -27 months).All cases had no complications such as incision infection,skin necrosis,internal fixator loosening or rupture and bone nonunion.Using AOFAS,the scores were 82.9 and 89.7 respectively at the 6 month and 12 month follow up.The degree of arthrosis was grades Ⅰ in 2 ankles,Ⅱ in 1 ankle,and Ⅲ in 1 ankle according to Kellgren&Lawrence.Conclusion Posteromedial combined with lateral surgical approach for the treat-ment of trimalleolar factures has leaded to an satisfactory clinic outcomes.It is minimally invasive and has less compli-cations and cost.
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Objective To study the distribution characteristics of radon progeny at different air quality index (AQI) and evaluate health risks for the exposed population.Methods EQF3120 Monitor was used to monitor the concentration of radon and its daughters.The relevant air quality data was provided by the environmental monitoring station at Suzhou Industrial Park.SPSS 16.0 software was used for statistical description,principal component analysis and simple correlation analysis.Environmental radon exposure-caused effective dose to lung region was estimated by using the radon dose formulas.Results Radon progeny in fog haze weather in winter of Suzhou Industrial Park had relationships with NO2,SO2,O3,PM10 and PM2.5.The correlation coefficient of 214Bi were 0.741,0.681,-0.431,0.597 and 0.675.The correlation coefficient of radon progeny with PM2.5 was greater than that with PM10.When AQI ＞ 200,the effective dose to residents outdoor from radon and its short-lived progeny was 0.63 mSv/a.Conclusions Higher AQI results in higher concentration of attached radon progeny.There is little variation in concentration of unattached radon progeny.Fog and haze can increase exposure of the population to inhalated radon.