Tumour volume distribution can yield information on tumour growth and tumour control

BackgroundIt is shown that tumour volume distributions can yield information on two aspects of cancer research: tumour induction and tumour control.Materials and methodsFrom the hypothesis that the intrinsic distribution of breast cancer volumes follows an exponential distribution, firstly the probability density function of tumour growth time was deduced via a mathematical transformation of the probability density functions of tumour volumes. In a second step, the distribution of tumour volumes was used to model the variation of the clonogenic cell number between patients in order to determine tumour control probabilities for radiotherapy patients.ResultsDistribution of lag times, i.e. the time from the appearance of the first fully malignant cell until a clinically observable cancer, can be used to deduce the probability of tumour induction as a function of patient age. The integration of the volume variation with a Poisson-TCP model results in a logistic function which explains population-averaged survival data of radiotherapy patients.ConclusionsThe inclusion of tumour volume distributions into the TCP formalism enables a direct link to be deduced between a cohort TCP model (logistic) and a TCP model for individual patients (Poisson). The TCP model can be applied to non-uniform tumour dose distributions.     

手术治疗胫腓骨远端骨折36例

目的 :探讨胫腓骨远端骨折治疗术式的选择、术中术后应注意的问题及其疗效。方法 :对不同类型的胫腓骨远端骨折 36例进行 8～ 18个月的随访 ,并结合临床及影像学资料 ,对其诊断、手术方法及治疗效果进行分析总结。结果 :本组术后 2 5～ 3 5个月骨折均愈合。踝关节功能优良率 77 7%。结论 :熟悉骨折的分型及相应内固定术式的选择 ;注重踝穴骨折的解剖复位及固定和踝关节的功能位固定及早期功能锻炼。     

成都市暴雨洪涝与儿童手足口病关联分析及脆弱人群亚组识别

目的 刻画成都市2011—2017年暴雨洪涝与儿童手足口病(Hand, foot and mouth disease,HFMD)之间的短期滞后关系,并进一步量化在不同性别、年龄亚组中的效应,识别脆弱人群。方法 收集整理成都市2011年1月1日—2017年12月31日的15岁以下HFMD日发病数、气象因子和暴雨洪涝发生情况数据。以暴雨洪涝为关键自变量,运用准泊松分布滞后模型,探讨了暴雨洪涝发生后0~14天的滞后效应。结果 研究发现暴雨洪涝与儿童手足口病呈正相关关系。0~7天和0~14天的累积滞后效应分别为1.11(95% CI:1.01~1.22)和1.21 (95% CI:1.04~1.41)。性别和年龄亚组分析分别表明,男童和3岁以下儿童（<1岁婴儿和1~2岁幼儿亚组）存在单日滞后统计显著的正相关关系,且0~7天和0~14天的累积滞后均显著;女童的单日滞后没有统计学意义,仅0~14天累计滞后统计显著,且效应略低于男童（女童: RR =1.23(1.00~1.51),男童: RR =1.26(1.06~1.51)）;<1岁婴儿0~7天和0~14天的累积滞后效应最强,分别为1.26(95%CI:1.02~1.57)和1.68(95%CI:1.20~2.34)。结论 暴雨洪涝会增加儿童患HFMD的风险,尤其是男童和3岁以下的婴幼儿（对1岁以下的婴儿的影响最大）。利益相关者应充分意识到暴雨洪涝的健康风险。家庭、社区、学校和政府应共同努力,减少暴雨洪涝相关的儿童HFMD。     

Comparative Analysis of Osteosynthesis of Mandibular Anterior Fractures Following Open Reduction Using ‘Stainless Steel Lag Screws and Mini Plates’

Introduction

The purpose of this study was to compare the outcome of open treatment of mandibular fracture (symphysis or parasymphysis) using lag screw or mini plate clinically as well as radiologically in young (age range 12–45 years) and healthy individuals of poor socioeconomic status.

Method

This prospective study was conducted on 30 patients diagnosed as cases of displaced mandibular anterior fractures treated with open reduction and internal fixation. The patients were then randomly allocated to either of two groups––Group A: Two 2.5 mm stainless steel lag screws were placed in 15 patients. Group B: Two 2.5 mm stainless steel mini plates were placed in 15 patients for the fixation of fractures. Subsequent follow up was done on 2nd, 4th, 6th and 8th week postoperatively. During every follow up patient was assessed clinically for infection, malocclusion, loosening of plate/screw, sensory disturbance, plate fracture, malunion/non-union, devitalisation of associated dentoalveolar segment and masticatory efficiency. Radiographs were taken if necessary and patients were further assessed for any complaint. Pain was objectively measured using a visual analogue scale, bite force was measured using a bite force transducer at biweekly interval. The data collected was subjected to unpaired t test and paired t test for statistical analysis.

Results

During follow up period a significant improvement in bite force was present in both the groups, with more improvement seen in the lag screw group (p < 0.01). There was a significant pain reduction present in the lag screw group (p < 0.01) and also masticatory efficiency showed a steadier improvement in lag screw group while mini plate group patients showed a tendency to masticate only food items of medium hard consistency.

Conclusion

The sample size is small to conclude lag screws are better than mini plates but the result of our study provides a basis for further studies done to conclude that the application of LAG SCREW is an effective, inexpensive, quick treatment modality to accelerate healing of fresh, displaced mandibular anterior fracture.     

宝鸡市区气象因素与手足口病的滞后效应研究

目的初步研究宝鸡市区气象因素与手足口病的滞后效应。方法手足口病资料来源于“国家疾病监测信息报告管理系统”中2012年4～10月网络直报数据;同期气象因素数据来源于宝鸡市气象局。数据分析用R3．0．2软件分布滞后非线性模型（distributedlagnon．1inearmoitels,DLNM）分析包。结果宝鸡市区手足口病日发病人数与平均气温、平均气压和平均水汽压相关,在温度较高（20℃以上）情况下,温度对手足口病发病滞后效应出现在大约5d左右;在温度较低（20℃以下）情况下,温度对手足口病发病滞后影响出现在大约10d左右。结论宝鸡市区气象因素对手足口病发病影响明显,温度对手足口病日发病存在明显的滞后效应。     

Minimal invasive para-rectus approach for limited open reduction and percutaneous fixation of displaced acetabular fractures

Introduction

Minimal invasive fixation has been reported as an alternative option for treatment of acetabular fractures to avoid blood loss and complications of extensive approaches. Closed reduction and percutaneous lag screw fixation can be done in minimally displaced acetabular fractures. Open reduction is indicated, if there is wide displacement. In this study, we report the use of a mini-open anterior approach to manipulate and reduce anteriorly displaced transverse acetabular fractures combined with percutaneous lag screw fixation.

Methods

This report included eight patients. All had anterior displaced simple transverse acetabular fractures. An oblique mini-incision was made above and medial to the mid-inguinal point, and lateral to the lateral border of rectus abdominis muscle. The external abdominal oblique aponeurosis was incised along its fibres. The arched fibres of internal abdominal oblique were displaced medially above the inguinal ligament to expose and incise the fascia transversalis. Care was taken to avoid injury of ilioinguinal nerve, inferior epigastric vessels, and spermatic cord. The external iliac vessels were palpated and protected laterally. A blunt long bone impactor was introduced through this small incision to manipulate and reduce the fracture under fluoroscopic control. Fluoroscopic guided percutaneous lag screw fixation was done in all patients.

Results

The average time to operation was 4 days. Average blood loss was 110 mL. Operative time averaged 95 min. Maximum fracture displacement averaged 10 mm preoperatively and 1.3 mm postoperatively. According to Matta score, anatomical reduction of the fracture was achieved in five patients and imperfect in three. Follow up averaged 27 months. Wound healing occurred without complications and fracture union was achieved without secondary displacement in all patients. Average time to fracture healing was 14 weeks. According to the modified Merle d’Aubigné score, functional outcome was good to excellent in all patients.

Discussion and conclusion

Limited open reduction can solve the problem of fracture reduction, which is the main concern in minimal invasive fixation of acetabular fractures. It may help the inclusion of displaced acetabular fractures for percutaneous lag screw fixation. This mini-para-rectus approach has the advantages of minimal soft tissue dissection with the possible anatomical reduction of simple transverse displaced acetabular fractures.     

Treatment of early cut-out of a lag screw using a trochanter supporting plate: 11 consecutive patients with unstable intertrochanteric fractures

Introduction Superior cut-out of a lag screw remains a serious complication in the treatment of intertrochanteric fractures. It is related to the stability of fracture reduction. We describe the application of a trochanter supporting plate (TSP) to restore the fracture stability after early cut-out of a lag screw in unstable intertrochanteric fractures.Materials and methods A total of 11 consecutive patients with superior cut-out of the lag screw of a dynamic hip screw (DHS) or a gamma nail in an unstable intertrochanteric fracture occurring within 6 months after surgery were included in the present study. They underwent repeat surgery for placement of a DHS and a laterally mounted TSP of our design. All patients were monitored for at least 6 months (median 15 months; range 6–28 months).Results There was no repeated cut-out of a lag screw, and 10 patients (91%) achieved bony union within 5 months. At the last follow-up, all patients could walk with or without aids.Conclusion It reveals that a TSP, as an adjuvant to a lag screw placed inferiorly, is an easy and safe solution for the treatment of early cut-out of a lag screw in unstable intertrochanteric fractures.     

Intramedullary hip screw fixation of reverse oblique and transverse trochanteric femur fractures

Introduction  Reverse oblique and transverse trochanteric femur fractures (31A3) are relatively rare. They are associated with a high failure rate, particularly in cases where extramedullary implants are used. This study investigated a second-generation intramedullary nail in this specific fracture type. Methods  Flinders Medical Centre is a level 1 trauma centre and the largest user of the Intramedullary Hip Screw (IMHS, Smith and Nephew, Memphis, USA) in the Southern Hemisphere. Two hundred and forty-eight IMHS cases completed between September 2003 and August 2005 were retrospectively analysed. All fractures were classified using the AO/ASIF system (Muller et al., The comprehensive classification of fractures of the long bones, Springer, Berlin, 1990) and 31A3.1, 2, 3 fractures were selected. The case notes and radiology were reviewed over a 1-year follow-up. Results  Twenty-six cases were classified as 31A3 fractures. Thirty-eight percent of the cases received a long stem IMHS. Mean patient age was 81.9 years with a 1-year mortality of 11.5%. Two of the 26 cases (7.7%) had surgical complications, including one cut-out (associated with a tip-apex distance of 40.9 mm) and one loss of reduction. Both cases required re-operation. There were no femoral shaft fractures or non-unions in this series. Conclusions  This second-generation intramedullary implant, the IMHS, performed well in this often difficult to fix fracture. The complication rate is considerably less than the rate published for extramedullary implants and is comparable to previous studies using a range of intramedullary techniques.     

下颌骨加压螺钉钉道预备器的研制与应用

目的:研制一种在以加压螺钉固定下颌骨骨折时,在下颌骨上准确,快速地预备出加压螺钉钉道的手术器械,方法:该器械的由主托架,骨固定夹,万向关节及麻花钻导和管组成,骨固定夹夹持固定骨折断端,万向关节用以选择预定钉道及角度,结果:该器械在固定骨折断端的同时,用麻花钻连续制备出骨糈端外侧及内侧的钉道,保证了断端内外侧钉道的同轴性,2年来该器械成功地应用于6例下颌骨骨折治疗,显示了该器械的优越性能.结论:研制出的下颌骨用加压螺钉钉道预备器简化了手术操作,准确,快速地预备出加压螺钉钉道.     

Open reduction and internal fixation of intraarticular tibial plateau nonunions

The vast majority of tibial plateau fractures heal uneventfully, and no case series on intraarticular tibial plateau nonunions exists. The purpose of the present study was to evaluate the radiographic and clinical outcome of these nonunions following surgical treatment in a single surgeon series. Five patients with tibial plateau nonunions were treated at our institution using a specific treatment protocol consisting of open reduction and debridement, deformity correction, internal fixation including lag screws, bone graft augmentation, and selective knee joint arthrolysis. Patient outcomes were assessed using radiographs and the Knee Society questionnaire scores. Following surgical treatment of the nonunion, all healed at an average of 12.8 weeks, and average follow-up was 44 months. Preoperative coronal plane deformity was corrected in all patients. The final knee motion arc averaged 120 degrees postoperatively. Both the pain and function subscales of the Knee Society Rating scale improved significantly. Four of the five returned to their normal pre-injury activities, but two patients required total knee arthroplasty which was performed successfully after healing of the nonunion. With meticulous surgical technique and a standard protocol, healing may be reliably achieved. Arthrosis occurs frequently, and may occur primarily at the time of injury or from chronic alteration of intraarticular contact forces secondary to development of a nonunion.