Gastrotracheal fistula:Treatment with a covered self-expanding Y-shaped metallic stent

A 67-year-old man had a sev-ere cough and pulmonary infection for 1 wk before seeking evaluation at our hospital.He had undergone esophagectomy with gastric pull-up and radiotherapy for esophageal cancer 3 years previously.After admission to our hospital,gastroscopy and bronchoscopy revealed a fistulous communication between the posterior tracheal wallnear the carina and the upper residual stomach.We measured the diameter of the trachea and bronchus and determined the site and size of the fistula using multislice computed tomography and gastroscopy.A covered self-expanding Y-shaped metallic stent was implanted into the trachea and bronchus.Subsequently,the fistula was closed completely.The patient tolerated the stent well and had good palliation of his symptoms.

Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide) synthesized by ATRP

Novel Y-shaped block copolymers of poly（ethylene glycol） and poly（N-isopropylacrylamide）, PEG-b-（PNIPAM）2, were successfully synthesized through atom transfer radical polymerization （ATRP）. A difunctional macroinitiator was prepared by esterification of 2,2-dichloroacetyl chloride with poly（ethylene glycol） monomethyl ether （PEG）. The copolymers were obtained via the ATRP ofN-isopropylacrylamide （NIPAM） at 30℃ with CuCl/Me6TREN as a catalyst system and DMF/H2O （v/v = 3：1） mixture as solvent. The resulting copolymers were characterized by gel permeation chromatography （GPC） and ^1H NMR. These block copolymers show controllable molecular weights and narrow molecular weight distributions （PDI 〈 1.15）. Their phase transition temperatures and the corresponding enthalpy changes in aqueous solution were measured by differential scanning calorimetry （DSC）. As a result, the phase transition temperature of PEG45-b-（PNIPAM55）2 is higher than that of PNIPAM, however, the corresponding enthalpy change is much lower, indicating the significant influence of the macromolecular composition and architecture on the phase transition.

基于Y-shaped路网的早高峰拼车定价策略

针对交通资源配置有限导致的早高峰通勤拥堵问题,借鉴共享经济理论,引入拼车出行概念,充分考虑通勤者出行方式和Y-shaped路网特点,建立了基于通勤者出行效益的拼车定价模型.模型结合费用补偿机制,讨论了以平台利润最大化和系统负效用最小化为目标的拼车定价策略,并给出了定价策略有效的阈值条件.研究结果表明,当通勤者都参与到拼车服务中时,拼车平台利润和交通系统负效用在其相应拼车定价策略下均能达到最优值,并且以交通系统负效用最小化为目标的拼车定价策略能消除Y-shaped路网中瓶颈处的交通拥堵.

Deformation and defects in hydroforming of Y-shaped tubes

Hydroforming process of a Y-shaped stainless steel tube was investigated through numerical simulation and experiments. The forming process and reasons of typical defects were analyzed with three different loading paths. Thickness distribution of formed Y-shaped tube was obtained. It is shown by numerical and experimental results that the transition regions are depressed in the forming condition of low inner pressure and wrinkles occur, while fracture occurs in the forming condition of high inner pressure. After forming, the thickness in left transition fillet region is the largest, that in fight transition fillet region is thinner, and the thinnest thickness is at the top of the protrusion. The original thickness line is below the top of the protrusion. The thinning area occurs above this line, while the thickening area is below this line. The maximum thinning rate is significantly increased as the calibration pressure increases, while the maximum thickening rate remains almost unchanged.

Binary collision approximation for solitary waves in a Y-shaped granular chain

We implement a binary collision approximation to study solitary wave propagation in a two-dimensional double Y- shaped granular chain. The solitary wave was transmitted and reflected when it met the interface of the bifurcated branches of the Y-shaped granular chains. We obtain the analytic results of the ratios of the transmitted and reflected speeds to the incident speed of the solitary wave, the maximum force between the two neighbor beads in a solitary wave, and the total time taken by the pulse to pass through each branch. All of the analytic results are in good agreement with the experimental observations from Daraio et al. [Phys. Rev. E 82 036603 （2010）]. Moreover, we also discuss the delay effects on the arrival of split pulses, and predict the recombination of the split waves traveling in branches in the final stem of asymmetric systems. The prediction of pulse recombination is verified by our numerical results.

Evaluation of ultimate bearing capacity of Y-shaped vibro-pile

Based on Mindlin stress solution, a numerical computational method was proposed to calculate the stresses in the ground induced by side friction and the resistance of Y-shaped vibro-pile. The improved Terzaghi's and ЪерезанцевВГ's methods for ultimate bearing capacity evaluation were proposed by considering the stress strength induced by friction resistance at pile head level of Y-pile. A new method to calculate the ultimate bearing capacity of Y-pile was also proposed based on the assumptions of soil failure mode at the tip of Y-pile and the use of Mohr-Coulomb soil yield criterion and Vesic compressive correction coefficient with the induced stresses in the ground. Based on the comparisons with the field static load test results, it is found that the improved Terzaghi's method gives higher ultimate capacity, while the other two methods shows good agreement with the field results.

Unicompartmental knee arthroplasty vs high tibial osteotomy for knee osteoarthritis:A comparison of clinical and radiological outcomes

BACKGROUND Unicompartmental knee arthroplasty(UKA)and high tibial osteotomy(HTO)are well-established operative interventions in the treatment of knee osteoarthritis.However,which intervention is more beneficial to patients with knee osteoarthritis remains unknown and a topic of much debate.Simultaneously,there is a paucity of research assessing the relationship between radiographic parameters of knee joint alignment and patient-reported clinical outcomes,preoperatively and following HTO or UKA.AIM To compare UKAs and HTOs as interventions for medial-compartment knee osteoarthritis:Examining differences in clinical outcome and investigating the relationship of joint alignment with respect to this.METHODS This longitudinal observational study assessed a total of 42 patients that had undergone UKA(n=23)and HTO(n=19)to treat medial compartment knee osteoarthritis.Patient-reported outcome measures(PROMs)were collected to evaluate clinical outcome.These included two disease-specific(Knee Injury and Osteoarthritis Outcome Score,Oxford Knee Score)and two generic(EQ-5D-5L,Short Form-12)PROMs.The radiographic parameters of knee alignment assessed were the:Hip-knee-ankle angle,mechanical axis deviation and angle of Mikulicz line.RESULTS Statistical analyses demonstrated significant(P<0.001),preoperative to postoperative,improvements in the PROM scores of both groups.There were,however,no significant inter-group differences in the postoperative PROM scores of the UKA and HTO group.Several significant correlations associated a more distolaterally angled Mikulicz line with worse knee function and overall health preoperatively(P<0.05).Postoperatively,two clusters of significant correlations were observed between the disease-specific PROM scores and knee joint alignment parameters(hip-knee-ankle angle,mechanical axis deviation)within the HTO group;yet no such associations were observed within the UKA group.CONCLUSION UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with medial compartment knee osteoarthritis.Clinical outcome has a limited association with radiographic parameters of knee joint alignment postoperatively;however,a more distolaterally angled Mikulicz line appears associated with worse knee function/health-related quality of life preoperatively.

Transfer characteristics of dynamic biochemical signals in non-reversing pulsatile flows in a shallow Y-shaped microfluidic channel: signal filtering and nonlinear amplitude-frequency modulation

The transports of the dynamic biochemical signals in the non-reversing pulsatile flows in the mixing microchannel of a Y-shaped microfluidic device are ana- lyzed. The results show that the mixing micro-channel acts as a low-pass filter, and the biochemical signals are nonlinearly modulated by the pulsatile flows, which depend on the biochemical signal frequency, the flow signal frequency, and the biochemical signal transporting distance. It is concluded that, the transfer characteristics of the dynamic biochemical signals, which are transported in the time-varying flows, should be carefully considered for better loading biochemical signals on the cells cultured on the bottom of the microfluidic channel.

Y-Shaped Intra-Scleral Fixated Lens versus Retro-Pupillary Iris Claw Lens in the Treatment of Aphakia

Background: Many reasons can lead to an aphakia without adequate capsular support for implantation of a posterior chamber intraocular lens (IOL), such as intraoperative unintentional rupture of posterior capsule during phacoemulsification, planned intracapsular cataract extraction, ocular trauma and lens dislocation due to congenital and acquired causes. Purpose: To compare Y-shaped intra-scleral fixation of a posterior chamber IOL with retro pupillary fixation of an iris-claw intraocular lens (IOL) for Aphakic eyes without sufficient capsular support as respects safety, visual recovery and complications of both methods. Patients and Methods: One hundred Aphakic eyes were arbitrarily distributed between two groups. Group A included 50 eyes treated with retropupillary fixation of iris claw lens and group B included 50 eyes treated with Y-shaped intra-scleral fixation technique. Preoperative, intraoperative and postoperative data were analysed including best corrected visual acuity (BCVA), intraocular pressure (IOP), surgical time, intraoperative problems, IOL malposition and postoperative complications. Following up on patients was carried out for at least six months. Results: The mean duration of surgery was 21 ± 5.3 min in group A and was 53.4 ± 6.9 min in group B (p-value 0.05). IOL tilt was found in 0 (0%) eyes in group A and in 5 (10%) eyes in group B (p 0.05). Conclusion: The results of our study indicated that both methods are satisfactory in correcting aphakia without sufficient capsular support as regards postoperative best corrected visual acuity (BCVA);however the surgical technique of retropupillary iris claw lens is easier, shorter, with low intra- and postoperative complications and safer than those used for intra-scleral fixation of IOL. But for eyes which lack both iris and capsular support, a scleral fixation of a posterior chamber IOL remains the only option.

Comparison of lag screws and double Y-shaped miniplates in the fixation of anterior mandibular fractures

BACKGROUNDMandibular fractures constitute about 80.79% of maxillofacial injuries inAlexandria University, either as isolated mandibular fractures or as a part ofpanfacial fractures. The combination of symphyseal and parasymphyseal fracturesrepresent 47.09% of the total mandibular fractures.AIMTo compare the effectiveness of lag screws vs double Y-shaped miniplates in thefixation of anterior mandibular fractures.METHODSThis study is a prospective randomized controlled clinical trial, performed onsixteen patients with anterior mandibular fractures. Patients were divided equallyinto two groups, each consisting of eight patients. Group 1: Underwent openreduction and internal fixation using two lag screws. Group 2: Underwent openreduction and internal fixation using double Y-shaped plates. The followingparameters were assessed: operating time in minutes, pain using a visual analogscale, edema, surgical wound healing for signs and symptoms of infection,occlusion status and stability, maximal mouth opening, and sensory nervefunction. Cone beam computed tomography was performed at 3 and 6 mo tomeasure bone density and assess the progression of fracture healing.RESULTSThe study included 13 males (81.3%) and 3 females (18.8%) aged 26 to 45 years(mean age was 35.69 ± 6.01 years). The cause of trauma was road traffic accidentsin 10 patients (62.5%), interpersonal violence in 3 patients (18.8%) and othercauses in 3 patients (18.8%). The fractures comprised 10 parasymphyseal fractures(62.5%) and 6 symphyseal fractures (37.5%). The values of all parameters were comparable in both groups with no statistically significant difference except forthe mean bone density at 3 mo postoperatively which was 946.38 ± 66.29 in group 1 and 830.36 ± 95.53 in group 2 (P = 0.015).CONCLUSIONBoth lag screws and double Y-shaped miniplates provide favorable means offixation for mandibular fractures in the anterior region. Fractures fixed with lagscrews show greater mean bone density at 3 mo post-operation, indicative ofhigher primary stability and faster early bone healing. Further studies with largersample sizes are required to verify these conclusions.

Knee Osteoarthritis Progression after Distal Femur Closing Wedge Osteotomy

Background: Despite the conservative treatment of tibio-femoral osteoarthritis through realignment osteotomies, the rate of total knee replacements following an osteotomy is increasing. The aim of this study was to identify the factors associated with the progression of knee osteoarthritis after a medial closing-wedge distal femoral osteotomy. Methods: Hospital-based observational study on 20 patients who underwent a medial closing-wedge distal femoral osteotomy evaluating the progression of osteoarthritis using the Kellgren and Laurence classification. The Wilcoxon test was used to compare the variation in the progressive stage of the Kellgren and Laurence classification of knee osteoarthritis preoperatively and at the final follow up. Univariate analysis made it possible to determine the factors associated with progression. The final significance threshold for statistical tests was set at 5% (p Results: Overall, the mean follow-up of 46 months ± 6.6 months, with a mean age of 43 years (range: 27 - 69 years) and a female predominance (M: F = 3/7). The progression of tibiofemoral osteoarthritis following a medial closing-wedge distal femoral osteotomy is associated with valgus or varum malalignment been a moderate valgus (OR 6.2 [1.5 - 42.7] at 95% CI;p-value = 0.02), a correction of the mechanical deviation angle with a valgus alignment (OR 2.7 [0.9 - 8.3] at 95% CI), and loss of correction (OR 3.8 [1.3 - 11.6] at 95% CI;p -value) for the lateral compartment while varus alignment (OR 1.7 [0.9 - 8.3] 95% CI, p-value = 0.05) and with rupture of the lateral cortex (OR 2.8 [1.7 - 11.5] 95% CI, p-value = 0.02) were those of the medial compartment. Conclusion: Distal femur closing wedge osteotomy does not definitively interrupt the progression of valgus knee osteoarthritis. The factors associated with the progression of this pathology are modifiable. Taking them into account when performing this surgical technique could improve the osteotomy survival curve.

Osteotomy Protocol for Implant Insertion of One Day Biotech: One Drill, One Implant

Background: Four factors determine the quality of an implantology kit: 1) Heat generated by the drills;2) Morphology of the osteotomy according to the diameter of the implant;3) Efficiency of collecting autologous bone;and 4) Osteotomy execution time. Materials and Methods: This article examines the heat produced by drills during osteotomy, focusing on the effect of the following factors: drilling technique;volume of autologous bone harvested;drilling time;implant primary stability;and the percentage of osseointegrated implants after primary healing. Discussion: The four factors mentioned above are analyzed based on the data obtained for sequential, biological, and One Drill milling techniques. Conclusions: 1) One Drill is the fastest technique for performing the osteotomy;2) All techniques stay within the biological temperature range of living bone, with the lowest increase in temperature achieved using One Drill with irrigation;3) The bone harvested showed no statistically significant differences between biological milling and the One Drill technique, both far superior to the sequential technique;and 4) There is no statistically significant difference in the number of osseointegrated implants among the three techniques analyzed.

Clinical outcomes of triceps reflecting anconeus pedicle and olecranon osteotomy approach for distal humerus intercondylar fractures

BACKGROUND The preferred treatment for distal humeral intercondylar fractures is open reduction and internal fixation.While there is consensus about the posterior approach,several posterior approaches have been developed.It is debatable as to which approach is best.AIM To compare triceps reflecting anconeus pedicle(TRAP)and olecranon osteotomy approaches for internal fixation of distal humeral intercondylar fracture.METHODS In total,40 cases of Arbeitsgemeinschaft für Osteosynthesefragen/Association of the Study of Internal Fixation type C,closed,and Gustilo type I intercondylar humeral fractures were included.Patients ranged in age from 18 years to 70 years.The patients were randomized into two groups:TRAP group and olecranon osteotomy group,with 20 cases in each.All were followed up at 6 wk,3 months,6 months,and 12 months.Functional outcomes were measured in terms of flexion-extension arc,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance Score.RESULTS The mean age was 43.2 years in the TRAP group and 37.5 years in the olecranon osteotomy group.The mean operative time and mean duration of hospital stay in the TRAP group were significantly higher than in the olecranon osteotomy group(119.5 vs 111.5 min and 9.85 vs 5.45 d,respectively).The mean arc of flexion-extension,Disabilities of Arm,Shoulder and Hand score,and Mayo Elbow Performance Score were comparable without any significant difference in the groups at the 12-month follow-up(107.0 vs 106.2,18.3 vs 15.7,and 84.2 vs 86.2,respectively).Ulnar paresthesia and superficial infections were comparable in both groups(2 cases vs 3 cases and 3 cases vs 2 cases,respectively).Hardware prominence was significantly higher in the olecranon osteotomy group,mostly due to tension band wiring.CONCLUSION Both approaches were equivalent,but there is a need for further study including higher numbers of subjects and longer study duration to prove the benefits of one approach over the other.

Osteotomy combined with anterior cruciate ligament reconstruction for anterior cruciate ligament injury and biplanar deformity

BACKGROUND It has been confirmed that the increased posterior tibial slope over 12 degrees is a risk factor for anterior cruciate ligament injury,and varus deformity can aggravate the progression of medial osteoarthritis.AIM To evaluate the efficacy of modified high tibial osteotomy(HTO)and anterior cruciate ligament reconstruction(ACLR)in the treatment of anterior cruciate ligament(ACL)injuries with varus deformities and increased posterior tibial slope(PTS)based on clinical and imaging data.METHODS The patient data in this retrospective study were collected from 2019 to 2021.A total of 6 patients were diagnosed with ACL injury combined with varus deformities and increased PTS.All patients underwent modified open wedge HTO and ACLR.The degree of correction of varus deformity and the PTS was evaluated by radiography and magnetic resonance imaging.RESULTS All 6 patients(6 knee joints)were followed up for an average of 20.8±3.7 months.The average age at surgery was 29.5±3.8 years.At the last follow-up,all patients resumed competitive sports.The International Knee Documentation Committee score increased from 50.3±3.1 to 87.0±2.8,the Lysholm score increased from 43.8±4.9 to 86±3.1,and the Tegner activity level increased from 2.2±0.7 to 7.0±0.6.The average movement distance of the tibia anterior translation was 4.8±1.1 mm,medial proximal tibial angle(MPTA)was 88.9±1.3°at the last follow-up,and the PTS was 8.4±1.4°,both of which were significantly higher than those before surgery(P<0.05).CONCLUSION Modified open wedge HTO combined with ACLR can effectively treat patients with ACL ruptures with an associated increased PTS and varus deformity.The short-term effect is significant,but the long-term effect requires further follow-up.

Extracorporeal shock wave therapy in treating ischial non-union following Bernese periacetabular osteotomy:A case report

BACKGROUND Extracorporeal shock wave therapy(ESWT)is increasingly being recognized as an advantageous alternative for treating non-union due to its efficacy and minimal associated complications.Non-union following Bernese periacetabular osteotomy(PAO)is particularly challenging,with a reported 55%delayed union and 8%non-union.Herein,we highlight a unique case of ischial non-union post-PAO treated successfully with a structured ESWT regimen.CASE SUMMARY A 50-year-old patient,diagnosed with left ischial non-union following the PAO,underwent six cycles of ESWT treatment across ten months.Each cycle,spaced four weeks apart,consisted of five consecutive ESWT sessions without anesthesia.Regular X-ray follow-ups showed progressive disappearance of the fracture line and fracture union.The patient ultimately achieved a satisfactory asymptomatic recovery and bone union.CONCLUSION The results from this case suggest that this ESWT regimen can be a promising non-invasive treatment strategy for non-union following PAO.

髋臼周围截骨治疗对发育性髋关节发育不良骨盆矢状位倾斜的影响

背景:发育性髋关节发育不良指髋臼、股骨近端存在骨性结构畸型,可导致髋关节不稳及髋骨关节炎。髋臼周围截骨术是青少年及成年人非终末期发育性髋关节发育不良治疗的主要方式。骨盆倾斜在髋关节生物力学中发挥至关重要的作用,它決定了髋关节的应力方向。在髋关节疾病中可出现骨盆代偿性倾斜,以尽量减少髋关节的异常应力。目的:观察发育性髋关节发育不良患者行髋臼周围截骨治疗是否改变患者骨盆矢状位倾斜,并探讨髋臼覆盖对骨盆矢状位倾斜的影响。方法:回顾性分析2019年8月至2022年6月在四川大学华西医院因发育性髋关节发育不良行髋臼周围截骨的患者29例,收集患者术前及术后6个月站立位骨盆正位X射线片,测量髋关节外侧中心边缘角、通力氏角、耻骨联合到骶髂关节距离、耻骨联合到骶髂关节连线中点距离、骶骨-股骨头-耻骨角及骨盆矢状位倾斜;所有患者均于术前及术后6个月采用髋关节残疾及骨关节炎评分及Harris评分行髋关节功能评估。结果与结论:(1)与术前相比,术后6个月髋关节外侧中心边缘角、耻骨联合到骶髂关节连线中点距离、骶骨-股骨头-耻骨角均较术前显著增大(P <0.05);而通力氏角及骨盆矢状位倾斜则显著减小(P <0.05);耻骨联合到骶髂关节距离与术前无明显差异(P> 0.05);(2)术后6个月髋关节残疾及骨关节炎评分及Harris评分均较术前显著提高(P <0.01);(3)提示髋臼周围截骨显著改善了发育性髋关节发育不良患者的髋臼覆盖,且骨盆出现显著前倾改变。

膝关节单髁置换与胫骨高位截骨治疗内翻性膝骨关节炎的比较

背景:早期膝关节炎可行单髁置换和胫骨高位截骨等方法保膝治疗,但两种保膝手术在术后不同时期膝关节恢复方面是否存在差异仍需进一步探讨。目的:比较单髁置换和胫骨高位截骨治疗膝关节内翻性骨关节炎的疗效及相关并发症等方面的差异,为临床决策提供参考。方法:选择2018年9月至2022年9月南通大学附属医院行手术治疗的膝关节内翻性骨关节炎患者103例,其中86例获得1年以上随访,根据手术方法分为单髁置换组(n=49)和胫骨高位截骨组(n=37)。分别对两组患者术前及术后4周、3个月、6个月、1年的膝关节功能、疼痛以及力线纠正情况进行评估,采用美国特种外科医院膝关节评分、美国西安大略大学和麦克马斯特大学功能评分、膝关节外侧间隙变化、关节活动度、本体感觉(位置觉)、术后活动恢复速度等指标综合评判。结果与结论:(1)两组患者术前美国特种外科医院膝关节评分、美国西安大略大学和麦克马斯特大学功能评分、膝关节外侧间室大小均无显著差异;(2)术后4周单髁置换组的美国特种外科医院评分高于胫骨高位截骨组(P<0.05);在术后3,6个月,对比两组患者的改善情况,单髁置换组的美国特种外科医院评分低于胫骨高位截骨组,差异有显著性意义(P<0.05);术后6个月关节活动度屈曲值以及位置觉方面胫骨高位截骨组患者要优于单髁置换组(P<0.05);(3)在膝关节活动恢复速度方面单髁置换组要优于胫骨高位截骨组(P<0.05);(4)然而在术后1年的随访中,两组在美国特种外科医院膝关节评分、伸展方向活动度以及膝关节外侧间隙宽度变化上未见明显差异;(5)所有患者的随访数据均超过1年,且在随访期间均未发现不良并发症;(6)提示采用胫骨高位截骨治疗的内翻性膝骨关节炎患者膝关节功能恢复短期效果优于单髁置换患者,但两种方案治疗内翻性膝骨关节炎的中长期疗效无明显差异。

3D打印个体化截骨导板结合定制钢板在开放楔形胫骨高位截骨中的应用

背景:3D打印个体化截骨导板辅助开放楔形胫骨高位截骨治疗膝骨关节炎具有手术时间短、透视次数少、矫正精准度高等优点。但之前报道的截骨导板对周围软组织破坏严重、锁定钢板位置不当等问题依旧明显。目的:探究3D打印个体化截骨导板结合定制钢板辅助开放楔形胫骨高位截骨治疗膝骨关节炎的临床疗效。方法:收集20例确诊为膝骨关节炎的患者,按手术方法分为3D组和常规组,每组10例。3D组采用3D打印个体化截骨导板结合定制钢板辅助开放楔形胫骨高位截骨手术,常规组进行常规开放楔形胫骨高位截骨手术。分析比较两组患者手术时间、透视次数、切口长度,术前和术后髋膝踝角、胫骨近端内侧角、胫骨后倾角以及计划矫正角度与实际矫正角度的差值,术前和术后1,3,6个月膝关节活动度及Lysholm评分,另外记录并发症发生情况。结果与结论:①3D组患者的手术时间、透视次数少于常规组,差异有显著性意义(P<0.001);②两组患者的术后髋膝踝角、胫骨近端内侧角均较术前增大,差异有显著性意义(P<0.001),而胫骨后倾角无明显改变;3D组术后髋膝踝角、胫骨近端内侧角及胫骨后倾角与术前计划值分别相差(-0.22±0.72)°、(-0.20±0.73)°和(0.23±0.37)°,但差异均无显著性意义;3D组计划矫正度数与实际矫正度数的差值较常规组小,差异有显著性意义(P<0.05);③两组患者术后膝关节活动度及Lysholm评分均逐步升高(P<0.001);3D组术后1,3个月的膝关节活动度及术后1个月的Lysholm评分优于常规组,差异有显著性意义(P<0.05);两组患者术后3个月的Lysholm评分、术后6个月的膝关节活动度及Lysholm评分差异无显著性意义(P>0.05);④两组患者均无并发症发生;⑤上述结果说明3D打印个体化截骨导板结合定制钢板辅助和常规方法均有良好的临床疗效,但前者的手术时间更短,透视次数更少,术后膝关节功能恢复更快;并且3D打印个体化截骨导板可精准实现术前规划。

数字化精准全膝关节置换与传统置换方法的短期效果对比

背景:传统全膝关节置换手术在术前的准备有限,作者提出基于计算机仿真和3D打印技术的数字化精准全膝置换方法,旨在通过充分的术前设计来提升置换效果。目的:利用计算机仿真和个性化手术导板建立数字化精准全膝关节置换方法,比较新方法和传统方法的临床效果。方法:回顾性分析97例全膝关节置换患者的临床资料,根据手术方法将患者分为2组,对照组(n=48)采取传统方式进行全膝关节置换手术,使用传统胶片模板;观察组(n=49)采用数字化精准全膝置换方法进行手术,使用计算机辅助技术选定假体尺寸型号。比较两组患者的手术时间、术中出血量、术前及术后美国特种外科医院膝关节评分以及股骨力线和膝关节面线夹角和胫骨角、髋膝踝角与标准角度的差值。结果与结论:(1)两组患者术前性别、年龄、体质量指数、美国特种外科医院膝关节评分,以及胫骨角、股骨力线和膝关节面线夹角、髋膝踝角与标准角度的差值相比差异均无显著性意义(P> 0.05);(2)与对照组比较,观察组手术时间缩短、出血量减少;两组术后3个月膝关节美国特种外科医院膝关节评分对比术前均显著升高(P> 0.05),且术后3个月观察组评分高于对照组(P> 0.05);(3)两组之间胫骨角、股骨力线和膝关节面线夹角、髋膝踝角与标准角度的差值相比差异均有显著性意义,观察组优于对照组(P <0.05);(4)观察组股骨假体预测准确率为94%,对照组为58%;胫骨假体预测准确率为96%,对照组为62%;(5)提示数字化精准全膝关节置换相较传统全膝关节置换的手术时间更短、出血量更少、术后膝关节功能评分和力线恢复更好,具有良好的短期临床效果。

有限元法在儿童发育性髋关节发育不良及治疗中的作用

背景:发育性髋关节发育不良常易导致患儿肢体畸形,其诊疗的相关研究已逐渐明确;近来有限元法因其优势在发育性髋关节发育不良的相关研究中受到学者重视。目的:通过文献检索综述有限元法在儿童发育性髋关节发育不良及治疗中的研究进展,分析总结其优势与不足,并探讨未来进一步研究的方向及应用前景。方法:应用计算机在Pub Med、SCI、CBM和中国知网数据库中检索2014年1月至2023年11月发表的相关文献,以“developmental dysplasia(dislocation) of the hip,dysplasia of the hip,finite element analysis(method),pavlik harness,fixation in herringbone position,biomechanics,pelvic osteotomies,pemberton,salter,dega,periacetabular osteotomy,children”为英文检索词,以“发育性髋关节发育不良,发育性髋关节脱位,髋关节发育不良,儿童,有限元,Pavlik吊带,人字型固定,生物力学,骨盆截骨术,髋臼周围截骨术”为中文检索词,同时纳入少量远期文献,通过筛选最终纳入62篇文献进行分析。结果与结论:(1)儿童发育性髋关节发育不良髋关节力学环境异常,髋臼内部压力不均匀、应力增大并集中,关节接触面积减小,股骨颈局部应力集中;(2)在Pavlik吊带及人字型固定位患髋力学环境改善,集中的高应力区域消失,关节接触面积增加,但外展角度过大会导致髋臼及股骨头外侧应力增加;(3)骨盆截骨术治疗后髋关节及骶髂关节应力环境得到改善,3种截骨术没有单一的铰链,其应力负载部位因患儿年龄而存在差异;(4)髋臼周围截骨术治疗后关节接触压力接近正常,而非球形股骨头者恢复困难;(5)术后X射线片表现不能说明关节接触力学达到最佳;(6)提示利用有限元法可以获得体内无法测量的信息,其在虚拟环境中操作不受时间和伦理的限制;能直观地看到正常与发育性髋关节发育不良患者髋关节应力变化的区域,从力学角度说明治疗的有效性,为需要截骨手术治疗的患者建立特定的有限元模型、量身定做手术计划;发育性髋关节发育不良的有限元建模及儿童髋关节材料特性参数尚无规范、统一的标准,由于有限元固有的局限性,目前还不能分析同时包含骨骼、软骨、韧带、肌肉等元素的模型;有限元分析操作难度较大,虽有优势但不具普适性,且目前的研究样本量较少,还需进一步扩大及验证。