Pelvic granulocytic sarcoma

 Granulocytic sarcoma is an uncommon extraskeletal tumor most frequently associated with leukemia. We present a case of bone location with unusual pattern in a patient with no evidence of myeloproliferative disorder at presentation or follow-up.     

冲击载荷作用下骨盆三维有限元分析及其生物力学意义

目的:探讨骨盆受到冲击载荷作用的力学行为特征,为临床分析及判断骨盆骨折类型、力学分布、冲击载荷影响提供力学基础。方法:采用计算机仿真模拟方法,将所构建骨盆三维实体模型导入三维有限元分析软件AN-SYS7.0,计算单侧髂前上棘和单侧髂骨正后方部位冲击载荷作用下骨盆的力学行为表现,冲击载荷为0～8000N,峰值8000N,时间自0～40ms,分析主应力值、应力分布情况以及主应力方向上骨盆单元的位移。结果:冲击载荷作用于单侧髂前上棘时,0～10ms主要的应力沿髂后上棘到髂前上棘分布,在冲击后期10ms以后,骶髂关节、髋臼和耻骨支都会产生较大的应力分布;作用于单侧髂骨正后方部位时,0～20ms主要的应力沿髂骨纵行传导,应力分布并没有在冲击峰值10ms时达到最大,而是从20ms之后,应力开始向骶髂关节、双侧耻骨支、坐骨支以及髋臼等部位传导并可见到明显的应力分布。结论:分析冲击载荷作用下骨盆各部位应力分布以及骨盆各个单元在应力作用下的位移变化,有助于临床上进行骨盆损伤内固定力点的选择以及进一步明确骨盆内在应力值分布。     

A multicenter clinical trial of gadolite oral suspension as a contrast agent for MRI

The purpose of this study was to assess the effectiveness and safety of Gadolite Oral Suspension as a gastrointestinal (GI) contrast agent for MRI in a phase II and two phase III multicenter clinical trials. Gadolite was administered to 306 patients with known or suspected abdominal and/or pelvic disease. MRI with T1- and T2-weighted sequences was performed before and after ingestion. Efficacy was evaluated by having two masked readers rate the certainty of their MR diagnosis (0 = uncertain, 1 = probable, 2 = definite) on randomly presented pre- and post-Gadolite Oral Suspension enhanced images. Principal investigators also evaluated the images and established the final diagnosis. Vital signs, clinical chemistries, and adverse events were documented. Blood and urine samples were analyzed for gadolinium content to determine whether Gadolite Oral Suspension was absorbed systemically. Certainty in MR diagnosis increased significantly (P < .001) for both blinded readers between pre- and post-Gadolite images (.49–1.18 for reader 1; .46–1.53 for reader 2). Sensitivity, specificity, and accuracy also increased for both masked readers. No gadolinium was detected in blood or urine samples. There were no serious adverse events and no apparent drug-related trends in mean vital signs or laboratory values. Gadolite is a highly effective, safe, and well tolerated contrast agent for clinical use with MRI.     

盆环原发恶性肿瘤的切除与生物学重建

目的:探讨骨盆环恶性肿瘤的切除、重建方式与并发症的处理 .方法:手术治疗骨盆环原发恶性或低度恶性肿瘤5例,其中骶骨恶性畸胎瘤2例、脊索瘤1例,髂骨骨肉瘤1例、恶性骨软骨瘤1例.所有患者术前未行动脉栓塞、结扎髂内血管.髂骨翼肿瘤采用自体髂骨、髋臼肿瘤采用异体骨重建骨盆环、自体股骨头重建髋臼骨床 人工全髋关节置换术.结果:5例肿瘤均行根治性切除,3例骶骨肿瘤术中出血量150～800 mL,术后出血300～1 000 mL,1例切口感染,1例术后出现失血性休克.髂骨翼肿瘤和髋臼周围肿瘤术中出血量分别为1 000 mL和4 000 mL,术后分别为800 mL和1 100 mL.髂骨肿瘤切除与重建患者2月后恢复关节功能,髋臼肿瘤切除与重建患者6月后恢复功能,4例患者术后随访4～24个月,生存良好.结论:骨盆环恶性肿瘤的外科手术治疗关键是完整的手术切除,包膜外切除可以减少出血、预防复发,影响骨盆环稳定时应考虑重建,自体、异体骨移植能够恢复髋臼周围骨量、维持骨盆环生物学稳定.     

Reliability of the acetabular teardrop as a landmark

Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.

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La valeur du sourcil cotyloidien comme repère d'analyse radiologique

Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.

     

Assessment of instability in type B pelvic ring fractures

Pelvic ring fractures have increased in incidence and operative fixation over the past several decades. These are dynamic injuries but decisions on operative management are still often made on the basis of static imaging. Expert opinion varies greatly on which injuries require fixation and how much fixation. Examination under anaesthesia has been shown to guide management of pelvic injuries by more accurately assessing levels of instability.     

基于螺旋CT构建人体骨盆三维有限元模型

目的 利用作者所在研究所自行开发的两种图像处理软件GETCT和MedGraphics，构建骨盆三维有限元模型。方法 CT图像处理、截面轮廓线信息处理、数字有限元分析。结果 准确快速的建立了人体骨盆的三维有限元模型。结论 利用上述两种软件以及一些现有的软件可以准确，快速地构建人体骨盆的三维有限元模型，并进行计算。有限元分析结果表明该方法可用于构建骨盆有限元模型。     

Vesicouterine fistula: MRI diagnosis

A case of vesicouterine fistula in a young woman following caesarean section is presented. The diagnosis was established successfully using heavily T2-weighted MRI which clearly demonstrated fluid within the fistula, obviating the need for conventional radiographic contrast examination. Received: 21 October 1998; Revised: 27 January 1999; Accepted: 1 March 1999     

The value of ‘binder-off’ imaging to identify occult and unexpected pelvic ring injuries

AimsTo determine the effectiveness of ‘binder-off’ plain pelvic radiographs in the assessment of pelvic ring injuries.Patients and methodsAll patients requiring operative intervention at our tertiary referral pelvic unit/major trauma centre for high-energy pelvic injuries between April 2012 and December 2014 were retrospectively identified. Pre-operative pelvic imaging with and without pelvic binder was reviewed with respect to fracture pattern and pelvic stability. The frequency with which the imaging without pelvic binder changed the opinion of the pelvic stability and need for operative intervention, when compared with the computed tomography (CT) scans and anteroposterior (AP) radiographs with the binder on, was assessed.ResultsSeventy-three percent (71 of 97) of patients had initial imaging with a pelvic binder in situ. Of these, 76% (54 of 71) went on to have ‘binder-off’ imaging. Seven percent (4 of 54) of patients had unexpected unstable pelvic ring injuries identified on ‘binder-off’ imaging that were not identified on CT imaging in binder.ConclusionsTrauma CT imaging of the pelvis with a pelvic binder in place is inadequate at excluding unstable pelvic ring injuries, and, based on the original findings in this paper, we recommend additional plain film ‘binder-off’ radiographs, when there is any clinical concern.     

Accuracy of computer-assisted iliosacral screw placement using a hybrid operating room

IntroductionIn recent years hybrid operating rooms were established all over the world. In our setting we combined a 3D flat-panel c-arm (Artis zeego, Siemens) with a navigation system (BrainLab curve, BrainLab). This worldwide unique combination enables the surgeon to visualise an entire pelvis in CT-like image quality with a single 3D-scan. The aim of our study was to investigate, if utilisation of a hybrid operating room increases the accuracy of SI-screws in comparison to standard 3D-navigation.Material and methodsRetrospective, not randomised single centre case series at a level I trauma centre. Inclusion criterion was insertion of a percutaneous iliosacral screw using image-guidance in the hybrid operating room. 61 patients (35 female, 26 male) were included from June 2012 till October 2014. 65 iliosacral screws were inserted. Intraoperative 3D-scans and postoperative scans were examined to investigate screw placement. The results were compared to a preceding study performed in 2012 using conventional 3D-navigation. Statistical calculations were performed with Microsoft Excel 2011 and SPSS.Results65 iliosacral screws were implanted. Two different types of screws were implanted: 1. “Standard” iliosacral screws stabilizing one joint/a unilateral fracture. 2. Single SI-screws stabilizing both SI-joints and if present a bilateral fracture. Forty one patients were included in group 1 (screws n = 45). There was no perforation in 43 screws, grade 1 perforation in 2 screws. There was no grade 2 or 3 perforation in this group. Compared to the conventional 3D-navigated screws there was a highly significant difference (p < 0.001). Twenty patients could be included in group 2. Eleven screws showed a complete intraosseous position. There was grade 1 perforation in 2 screws, grade 2 perforation in 5 screws and grade 3 perforation in 2 screws.ConclusionImprovements in image quality and enlargement of the display window lead to better intraoperative visualisation of the entire dorsal pelvis. Thereby the accuracy of computer-assisted iliosacral screws could be increased using a hybrid operating room. Furthermore difficult tasks like a single screw for both joints can be accomplished.