一种平板流动腔重力灌流系统的力学分析

本文分析了一种采用重力灌流的平板流动腔灌流系统，并根据实验结果确定出相应的阻力系数，获得平板流动腔剪应力、雷诺数以及入口长度与流体重力灌流高度的关系。     

Failure of the rabbit tibial growth plate to respond to the long-term application of a capacitively-coupled electrical field

A continuous 5-V peak-to-peak, 60 kHz capacitively-coupled sine wave signal was applied to the proximal tibial growth plate in fifteen 9-week-old male New Zealand white rabbits for 6 weeks. A pair of flexible stainless steel "injectrodes" was held in place medially and laterally on the surface of the proximal hindlimb in each rabbit by means of tape wrappings. The electrodes were connected to a 9-V battery-operated power unit carried in a dorsal pouch in a body vest worn by each rabbit. Control animals wore the identical apparatus, only the power unit was inactive. Small Tantalum markers were inserted into the anteromedial aspect of the proximal tibial metaphysis 1 cm distal to the proximal tibial growth plate in all of the animals, control and experimental, 2 weeks prior to the onset of electrical stimulation. The distance between the proximal lateral tibial spine and the Tantalum marker, between the Tantalum marker and the apex of the distal tibial intercondylar notch, and between the proximal tibial spine and the distal notch was measured from roentgenograms made at the time of bone marker insertion, at the time of electrode application to the limb, and at the end of the stimulation period. Results indicate that there was no significant difference in tibial lengths between the stimulated and control groups. There was significantly less total body weight gain in both the experimental and control animals than that which occurred in paired normal animals during the same period of time. This failure to thrive may be responsible for the resultant lack of longitudinal growth stimulation of the capacitive coupling.(ABSTRACT TRUNCATED AT 250 WORDS)     

老年转子间骨折角型钢板治疗失误和并发症分析

目的分析角型钢板治疗股骨转子间骨折中出现的各种失误和并发症,并提出预防措施。方法1990年10月以来共治疗股骨转子间骨折68例,逐例分析治疗失误的原因。结果术中操作失误致股骨外侧皮质崩裂2例;钢板刀口穿破股骨头进入髋臼1例,术后切口感染1例,共8例出现并发症,发生率14．7％。结论角型钢板治疗股骨转子间骨折效果好,但不应忽视可能发生的各种失误和并发症。     

肝包虫囊肿压迫下腔静脉的外科治疗

目的探讨肝包虫囊肿压迫下腔静脉的外科治疗。方法采用回顾性描述性研究方法。收集2013年5月至2018年5月石河子大学医学院第一附属医院收治的10例肝包虫囊肿压迫下腔静脉病人的临床资料;男7例,女3例;年龄为(46±5)岁,年龄范围为38~51岁。根据术中肝包虫囊肿与下腔静脉的贴合程度以及囊肿完整切除的难易程度,分别行外膜内外囊完整切除术、外膜内外囊次全切除术、外膜内外囊完整切除联合下腔静脉部分切除术。观察指标:(1)手术情况。(2)术后情况。(3)随访情况。采用门诊和电话方式进行随访,于术后3、6、12、24个月门诊随访1次。行彩色多普勒超声检查了解病人肝包虫囊肿复发及下腔静脉栓塞情况。随访终点为术后2年,随访次要终点为肝包虫囊肿复发。随访时间截至2020年5月。正态分布的计量资料以x±s表示。计数资料以绝对数表示。结果(1)手术情况:10例病人均顺利完成手术,7例行外膜内外囊完整切除术,2例行外膜内外囊次全切除术,1例行外膜内外囊完整切除联合下腔静脉部分切除术。10例病人术中无大出血及感染性休克发生。10例病人手术时间为(99±27)min;术中出血量为(99±48)mL。(2)术后情况:10例病人术后2~5 d拔除引流管,无术后出血、术后残腔感染、术后胆瘘发生,无围术期死亡病人,术后住院时间为(7.1±1.8)d。(3)随访情况:10例病人中,9例完成终点随访,随访时间内均无肝包虫囊肿复发及下腔静脉栓塞形成;1例病人于术后12个月,第3次随访失访,此病人术后3、6个月随访未发现肝包虫囊肿复发及下腔静脉栓塞。结论外膜内外囊完整切除术、外膜内外囊次全切除术、外膜内外囊完整切除联合下腔静脉部分切除术均能完整切除肝包虫囊肿。     

骨盆前环皮下内固定支架与微创经皮钢板内固定治疗骨盆前环骨折的疗效比较

目的 比较前环皮下内固定支架（INFIX）和微创经皮钢板内固定（MIPPO）治疗骨盆前环骨折的疗效。方法 回顾性分析2016年7月至2020年5月我院收治且符合标准的48例不稳定型骨盆骨折病人的临床资料,其中INFIX组22例,MIPPO组26例。INFIX组,男15例,女7例,年龄为（36.89±11.12）岁（21~58岁）。MIPPO组,男17例,女9例,年龄为（43.70±17.66）岁（21~71岁）。比较两组手术时间、术中出血量、骨折复位质量（Matta标准）、骨折愈合时间、骨折术后功能恢复情况（Majeed评分系统）,并记录并发症。结果 两组均获得随访,随访时间为5~17个月,平均为13个月。INFIX组手术时间[（75.41±15.25） min]低于MIPPO组[（85.62±17.92） min],差异无统计学意义（t=-5.154,P=0.101）;INFIX组术中出血量[（30.27±7.67） mL]明显低于MIPPO组[（111.15±24.30） mL],差异有统计学意义（t=-14.971,P=0.006）;两组负重时间[（16.00±2.06）周vs.（15.94±2.32）周]、Majeed评分[（81.90±7.73）分vs.（83.44±3.54）分]、骨折复位优良率[81.8% vs.84.6%]比较,差异均无统计学意义（P均＞0.05）,但MIPPO组能够达到更好的解剖复位。INFIX组1例病人出现股外侧皮神经损伤,两组病人未出现内固定失败情况。结论 治疗骨盆前环骨折,INFIX具有出血少、手术创伤小等优点,钢板能够达到更好的解剖复位,两组具有相似的术后功能恢复情况。可根据术者经验和病人具体情况选择适宜的固定方式。     

Tension band plates have greater risks of complications in temporary epiphysiodesis

PurposeThis study aimed to compare the efficacy of decreasing leg-length discrepancy (LLD) and postoperative complications between tension band plates (TBP) and percutaneous transphyseal screws (PETS).MethodsThis retrospective study reviewed LLD patients who underwent temporary epiphysiodesis at the distal femur and/or proximal tibia from 2010 to 2017 (minimum two years follow-up). Efficacy of decreasing LLD was assessed one and two years postoperatively. Complications were classified with the modified Clavien-Dindo-Sink complication classification system. Knee deformities were assessed by percentile and zone of mechanical axis across the tibial plateau.ResultsIn total, 53 patients (25 boys, 28 girls) underwent temporary epiphysiodesis (mean age, 11.4 years). The efficacy of decreasing LLD at two years between the TBP (n = 38) and PETS (n = 15) groups was comparable. Seven grade III complications were recorded in six TBP patients and in one PETS patient who underwent revision surgeries for knee deformities and physis impingement. Four grade I and two grade II complications occurred in the TBP group. The mechanical axis of the leg shifted laterally in the PETS group and medially in the TBP groups (+7.1 percentile versus -4.2 percentile; p < 0.05). Shifting of the mechanical axis by two zones was noted medially in four TBP patients and laterally in two PETS patients.ConclusionMore implant-related complications and revision surgeries for angular deformities were associated with TBP. A tendency of varus and valgus deformity after epiphysiodesis using TBP and PETS was observed, respectively. Patients and families should be informed of the risks and regular postoperative follow-up is recommended.Level of evidenceLevel III     

Association between Osteoporotic Vertebral Compression Fractures and Age,Bone Mineral Density,and European Quality of Life-5 Dimensions in Korean Postmenopausal Women: A Nationwide Cross-sectional Observational Study

BackgroudThe purpose of this study was to investigate the characteristics of osteoporotic vertebral compression fractures (OVCFs) in Korean postmenopausal women and the association between OVCFs and clinical factors such as age, bone mineral density (BMD), and quality of life.MethodsAccording to the population distribution in four regions in Korea, 1,281 postmenopausal female patients were recruited from nationwide orthopedic outpatient clinics. Radiologic, asymptomatic, and within 3 months of OVCF groups were analyzed based on age, fracture location, and prevalence according to BMD. In addition, BMD, T-score, body mass index, and European Quality of Life-5 Dimensions (EQ-5D) were investigated in the three groups, and the differences between groups were compared and analyzed.ResultsThe prevalence of radiologic OVCFs at the T11–L1 was 3.7 times higher in the 70s group (44.0%) than in the 50s group (11.9%). Femur and total hip BMD were significantly lower in patients with thoracolumbar junction fractures than in patients with L2–5 fractures, whereas no difference was observed in lumbar spine BMD. Of the three OVCF groups, the within 3 months of OVCF group had the lowest lumbar spine T-score of −2.445. The asymptomatic OVCF group also showed significantly lower lumbar spine T-score than did the group without radiologic OVCFs (p < 0.001). The EQ-5D showed a significant decrease in the radiologic OVCF group (p < 0.001) and within 3 months of OVCF group (p < 0.001).ConclusionsThe prevalence of OVCFs in the thoracolumbar junction rapidly increases with old age and low BMD in Korean postmenopausal women. Femur and total hip BMD are more predictive of thoracolumbar junction fractures than lumbar spine BMD. Patients with radiologic OVCFs had a significantly lower quality of life than no OVCF group. Therefore, this study shows it is important to treat and prevent osteoporosis before an OVCF occurs.     

The association between caudal block and urethroplasty complications of distal tubularized incised plate repair: experience from a South China National Children’s Medical Center

BackgroundThe effect of caudal block (CB) on the incidence of urethroplasty complications in hypospadias repair remains controversial. The evidence is conflicting, and some confounding bias issues need to be addressed. We sought to study a more homogenous group of distal hypospadias patients undergoing primary tubularized incised plate (TIP) repair by a senior pediatric urology surgeon in the past 2 years to examine the relationship between urethroplasty complications and the use of CB.MethodsWe reviewed our database to identify consecutive patients who had undergone hypospadias repairs by a senior director surgeon at our Center between January 2018 and November 2020. To be eligible to participate in the study, patients had to meet the following inclusion criteria: (I) have distal hypospadias; (II) have undergone a primary TIP repair; and (III) have attended follow-up appointments for a minimum period of 6 months. The primary outcome was the development of urethroplasty complications during the follow-up period. The principal variable of interest was whether or not CB was used perioperatively. The patients were categorized into a CB group (general anesthesia combined with CB) or a control group (general anesthesia only). Other potential risk factors were analyzed, including patient age at operation, patient weight, glans width, and the length of the urethral plate defect.ResultsThirty (12.2%) of the distal patients developed postoperative surgical complications. The postoperative surgical complication rates were similar between the different anesthesia groups. Weight, the length of the urethral plate length, and glans width did not contribute to the risk. Age was the only independent risk factor for postoperative surgical complications, and the complication rates increased in older patients.ConclusionsOur data from consecutive TIP repairs in distal hypospadias patients indicated no association between the use of CB anesthesia and the postoperative urethroplasty complication rate. Patients who were older in age when they underwent surgery had a higher risk of complications.