Computed tomography measurements of the acetabulum in adult dysplastic hips: which level is appropriate?

A study has been performed to evaluate whether one or several levels are needed with computed tomography (CT) study to provide sufficient information regarding anteversion and acetabular support to the femoral head. A total of 23 hips in 14 adults with uni- or bilateral congenital hip dysplasia (center-edge angle less than 20°) were assessed by obtaining 5-mm contiguous CT slices and performing acetabular measurements at four levels. Both anterior and posterior acetabular supports as quantified by the anterior and posterior acetabular sector angles were significantly lower than normal at all levels. The sector angles increased in the proximal cuts, whereas the acetabular anteversion increased caudally. Because no important additional information was gained by measuring at different levels, we conclude that CT study at one level is sufficient for acetabular measurements and suggest that the slice through the center of the femoral head is the most appropriate one.     

Radiographic measurements of dysplastic adult hips

 Hip dysplasia is a not uncommon feature in adults and can vary from subtle acetabular dysplasia to complex sequelae of developmental dysplasia of the hip. This review article describes the most useful radiographic measurements used to evaluate the adult hip. The frontal projection of the pelvis permits measurement of the center-edge angle (CE angle) and ”horizontal toit externe” angle (HTE angle), both of which assess the superior coverage of the acetabulum. The femoral neck-shaft angle (NSA) is also measured on this view. The false profile radiograph of the pelvis is described. It allows measurement of the vertical-center-anterior angle (VCA angle), which determines the anterior acetabular coverage and detects early degenerative hip joint disease. When surgery is contemplated, computed tomography (CT) is useful to better determine the anterior acetabular coverage by use of the anterior acetabular sector angle (AASA), and the posterior acetabular coverage by use of the posterior acetabular sector angle (PASA). CT also permits measurement of femoral anteversion. These measurements are particularly useful in the evaluation of acetabular dysplasia and for the preoperative assessment of the dysplastic hip.     

Three-dimensional computed tomography analysis of non-osteoarthritic adult acetabular dysplasia

OBJECTIVE: Little data exists on the original morphology of acetabular dysplasia obtained from patients without radiographic advanced osteoarthritic changes. The aim of this study was to investigate the distribution and degree of acetabular dysplasia in a large number of patients showing no advanced degenerative changes using three-dimensional computed tomography (3DCT). MATERIALS AND METHODS: Eighty-four dysplastic hips in 55 consecutive patients were studied. All 84 hips were in pre- or early osteoarthritis without radiographic evidence of joint space narrowing, formation of osteophytes or cysts, or deformity of femoral heads. The mean age at the time of CT scan was 35 years (range 15-64 years). 3D images were reconstructed and analyzed using recent computer imaging software (INTAGE Realia and Volume Player). Deficiency types and degrees of acetabular dysplasia were precisely evaluated using these computer software. RESULTS: The average Harris hip score at CT scans was 82 points. Twenty-two hips (26%) were classified as anterior deficiency, 17 hips (20%) as posterior deficiency, and 45 hips (54%) as lateral deficiency. No significant difference was found in the Harris hip score among these groups. The analysis of various measurements indicated wide variations. There was a significant correlation between the Harris hip score and the acetabular coverage (p < 0.001). CONCLUSION: Our results indicated wide variety of deficiency type and degree of acetabular dysplasia. Hips with greater acetabular coverage tended to have a higher Harris hip score.     

腰椎退变的CT表现（附300例分析）

笔者对３００例腰椎退变病人作了ＣＴ检查，就其ＣＴ表现进行分析，探讨退变的病理变化，引起临床症状的原因，为腰椎退变提供可靠的影像学根据。     

Use of general purpose mechanical computer assisted engineering software in orthopaedic surgical planning: advantages and limitations

Two surgical plans were developed for an appropriately complex reconstructive orthopaedic surgery case. One plan was developed with customary methods using two-dimensional (2D) radiographs. The second plan was developed with general purpose mechanical computer assisted engineering (MCAE) software using x-ray computed tomography (CT) data. The limitations of each method are identified. To create a surgical plan using three-dimensional (3D) medical datasets and MCAE software, five necessary steps were identified: (a) data reduction; (b) contour extraction; (c) 3D model creation; (d) extraction of mass properties; (e) model idealization. The principal limitation of general purpose MCAE software is the lack of pre-processing modules with which to address the unique requirements of medical image datasets.     

Chronic septic arthritis of the adult hip: computed tomographic features

Abnormalities on computed tomography (CT) are described in 12 adults in whom septic arthritis of the hip was diagnosed. Presenting symptoms varied, as did CT findings. Soft tissue abnormalities ranged from intra-articular effusion to large abscess formation, and bone changes ranged from minimal erosion of articular surfaces to gross destruction of the proximal femur and acetabulum. CT can be helpful in the evaluation of septic arthritis of the hip because of its superior demonstration of soft tissue detail. An accurate diagnosis can be established in unsuspected cases and can be confirmed when clinical indicators are vague.     

Pseudotumoural fibrous dysplasia of the maxilla: Radiological studies and computed tomography contribution

Clinical, radiological, and histological problems arise relating to fibrous dysplasia of the maxilla. Clinically, 11 of our 39 cases developed so rapidly that the lesions were suspected of being malignant. The histological diagnosis may be very difficult, since any tumoural, reactive, or healing process may simulate fibrous dysplasia. As a general rule, the diagnosis is established most easily by the radiological examination. The radiologist's responsibility is important, as mistakes may have serious consequences.We report four pseudotumoural forms of maxillary sinus fibrous dysplasia. All were characterised clinically by rapid evolution, radiologically by opacity of the sinus with apparent destruction of its wall, and histologically by difficulty in establishing the diagnosis. In two cases indeed, the initial histological interpretation was an osteogenic sarcoma. Due to its excellent densitometric resolution, computed tomography provides an invaluable contribution by displaying the fibrous wall of an intact or even thickened maxillary sinus when conventional radiology has suggested a destructive process. In difficult cases of maxillary fibrous dysplasia, computed tomography should be used as a supplementary investigation to establish the correct diagnosis.     

Radiology of an atypical fibro-osseous lesion confined to the nasal cavity

Fibro-osseous lesions of the sinonasal region are relatively frequent, but those strictly confined to the nasal cavity are rare. We report an atypical fibro-osseous lesion in the nasal cavity and describe its radiological features. The differential diagnosis is discussed. Received: 18 November 1997 Accepted: 6 April 1998     

成人髋臼发育不良性骨关节病的X线及CT表现分析

目的:探讨成人髋臼发育不良性骨关节病的X线及CT表现特征。方法:对73例92个成人髋臼发育不良性骨关节病的X线及CT资料进行回顾性分析,73例均拍摄标准的骨盆前后位X线片,42例行CT扫描。X线片上测量反映髋臼发育的指标:外侧中心边缘角(LCE角)、臼顶倾斜角(AI角)、髋臼角(Sharp角)及股骨头突出指数(FEI)。结果:92个成人髋臼发育不良性骨关节病的X线改变为:髋臼发育不良及继发性骨性关节炎,均符合髋臼发育不良的测量指标。42例53个髋CT显示髋臼顶发育不良16髋,髋臼前部发育不良28髋,髋臼前后部均发育不良9髋。结论:髋臼浅小、倾斜及髋臼关节面下囊变、股骨头骨赘是成人髋臼发育不良性骨关节病的常见及较特征性的表现,CT能够比X线片更早且更详细显示。髋臼指标测量能够量化评估髋臼发育不良的程度。     

CT detection of basal ganglion lesions in neurofibromatosis type 1: correlation with MRI

Summary Prospective study of CT and MRI in 41 consecutive children with suspected type 1 neurofibromatosis revealed basal ganglion lesions on T2-weighted spin echo images in 22 cases (54%) and on CT in only 7 of those (32%). T2-weighted spin-echo MRI also revealed multiple signal changes in the supra- and infratentorial white matter and brain stem that went completely unnoticed on CT.     

椎间盘退变的MRI与病理学研究

为阐明退变椎间盘ＭＲＩ征象的病理学基础及临床意义，作者对１１具成人脊柱标本椎间盘进行了ＭＲＩ与病理检查。根据检查结果，将间盘分为四型：Ⅰ型：正常间盘。ＭＲＩ上其形态及信号强度未见异常，病理仅见纤维环局部断裂。Ⅱ型：退变间盘。其形态不规则，信号强度不均匀减低，间盘未超过终板后缘。病理发现纤维环及软骨终板内有坏死的软骨细胞、破碎的髓核、出血、炎症、肉芽组织、纤维化及囊变等。Ⅲ型：间盘膨出。在退变的基础上，间盘呈同心性扩大并超出终板后缘，但无髓核局部脱出。病理见纤维环断裂，累及外环，表层尚完整。Ⅳ型：间盘脱出。除有Ⅱ型的改变外，髓核通过破裂的纤维环向后脱出，后纵韧带移位或破裂。     

Unexpected finding of elevated glucose uptake in fibrous dysplasia mimicking malignancy: contradicting metabolism and morphology in combined PET/CT

Fibrous dysplasia is a common benign disorder of bone in which fibro-osseous tissue replaces bone spongiosa. Lesions have a typical appearance on computed tomography (CT) images and regularly show a markedly increased uptake in bone scintigraphy using ^99mTc-labelled methylene diphosphonate (^99mTc-MDP) as radiotracer. The glucose avidity of these lesions depicted by positron emission tomography (PET) using the radiolabelled glucose derivative ¹⁸F-fluoro-2-deoxy-glucose (FDG) is less well known since FDG-PET does not have a role in the assessment of this disease. However, single cases have been reported in which fibrous dysplasia was present in patients undergoing FDG-PET scanning for oncological reasons, and no significant FDG uptake was observed for lesions identified as fibrous dysplasia. We report on a 24-year-old man with known fibrous dysplasia who underwent combined FDG-PET/CT scanning because of suspected recurrence of testicular cancer. In contrast to prior reports, a markedly elevated uptake of FDG was seen in numerous locations that were identified as fibrous dysplasia by CT. Based on this result, we conclude that fibrous dysplasia may mimick malignancy in FDG-PET and that coregistered CT may help to resolve these equivocal findings.     

肥大性下橄榄核变性的MRI浅析

目的 探讨肥大性下橄榄核变性(HOD)的MRI特征与临床表现,以期提高对该病的认识.方法 回顾性分析16例HOD患者的MRI表现,原发病变为脑干出血6例,脑干梗死3例,脑干挫裂伤1例,脑干脑炎1例,小脑出血4例,小脑肿瘤1例.16例均行T1WI、T2WI、FLAIR序列扫描,其中10例加做扩散加权成像和磁敏感加权成像序列.结果 MRI表现为单侧或双侧下橄榄核体积增大或无明显变化,T1WI呈等或稍低信号,T2WI呈稍高或高信号,FLAIR呈等或稍高信号,扩散加权成像上呈等信号,表观扩散系数图上呈稍高信号,磁敏感加权成像上无异常信号,对出血病灶显示最好.与原发性病变发生同侧HOD 6例,发生对侧HOD 4例,发生双侧HOD 6例.结论 MRI能非常清楚地显示下橄榄核的变性改变,但需结合临床病史、症状与体征才能对HOD做出明确诊断.     

成人髋关节X线测量及其临床应用

本文对520例(男、女各半)正常成人及94例成人髋臼结构不良的髋关节进行测量分析。认为Sharp角、髋臼指数和髋顶切线角是判断成人髋臼发育优劣的主要指标。Sharp角男、女性上限值分别为45°和47°;髋臼指数<21、髋顶切线角<0°为异常。上述三项指标值有二项不在正常范围内可诊断髋臼结构不良。作者主张用股骨头覆盖指数评价股骨头与髋臼之间的关系,其测量方法简单,定量准确,正常值为86.9±5.77,<75则说明关节有半脱位。     

MMP-2与椎间盘退变的关系

目的：研究基质金属蛋白酶-2与椎间盘退变的关系。方法：①颈间盘标本采集：2005-06~12于住院并手术治疗颈间盘突出症患者12例为研究组,共取颈间盘标本20个;对照组为同期住院并手术治疗颈椎骨折或脱位患者5例,共取颈间盘标本10个;②腰间盘标本采集：2005-06~12住院并手术治疗的46例腰间盘突出症患者间盘标本46个。利用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法直接测定国人椎间盘组织中的基质金属蛋白酶-2含量,并用LUZEX-F图象分析仪将电泳条带的深浅转化为灰度值来表示基质金属蛋白酶-2含量的多少。结果：①颈椎患病组与对照组间盘中基质金属蛋白酶-2的含量比较,患病组间盘中基质金属蛋白酶-2的含量明显高于对照组;②在退变突出的腰间盘中有基质金属蛋白酶-2的表达,并且随着间盘退变程度的加重,间盘中基质金属蛋白酶-2的含量逐渐升高。结论：人类退变的颈间盘中基质金属蛋白酶-2的含量较未退变的颈间盘明显增高;人类退变突出的腰间盘中含有基质金属蛋白酶-2,间盘退变程度与基质金属蛋白酶-2含量显著相关;基质金属蛋白酶-2在椎间盘退行性变化中可能起到重要作用。     

Three-dimensional CT measurement of adult acetabular dysplasia: technique, preliminary results in normal subjects, and potential applications

Objective. To assess a three-dimensional computed tomography (3DCT) technique for measurement of acetabular coverage in adults. Design. We used 3DCT to define the geometric centre of the femoral head and to measure centre-edge angles (CEAs) at 10° rotational increments around the acetabular rim. The means, ranges, standard deviations and 95% confidence intervals for the CEAs at the various rotational increments were determined. Inter- and intra-observer variability was measured. The normal values are compared with two example cases of acetabular dysplasia. Patients. The normal hips of 15 subjects aged 19–49 years (mean 34.2 years) were measured. Results. The 3DCT measurements are reproducible (mean difference inter-observer, 1.7°–7.9°; mean difference intra-observer, 0.6°–6.9°). Mean normal CEA at the lateral rim was 33° with a 95% confidence interval of 23°–43°. Mean normal CEAs at 10° rotational increments from anterior to posterior rim were determined, and graphed as a ’normal curve’. Conclusion. This new 3DCT method of assessing acetabular dysplasia is simple, reproducible, and applicable to diagnosis, quantification and surgical planning for adult acetabular dysplasia patients.     

MR imaging findings of acetabular dysplasia in adults

Objective To evaluate the diagnostic accuracy of MR imaging in the identification of labral and articular cartilage lesions in patients with acetabular dysplasia.Design and patients Pre-operative MR imaging was performed on 27 hips in 25 consecutive patients (16 males, 9 females, age range 19–52 years, mean age 31.2 years) with radiographic evidence of acetabular dysplasia (centre-edge angle of Wiberg <20 degrees). The average duration of symptoms was 16.2 months. Two musculoskeletal radiologists assessed MR images in consensus for the presence of abnormality involving the acetabular labrum and adjacent acetabular articular cartilage. A high resolution, non-arthrographic technique was used to assess the labrum and labral chondral transitional zone. Surgical correlation was obtained in all cases by a single surgeon experienced in hip arthroscopy and ten patients with normal hip MRI were included to provide a control group.Results The acetabular labra in the dysplastic hips demonstrated abnormal signal intensity, and had an elongated appearance when compared with the control group (mean length 10.9 mm vs 6.4 mm). Morphological appearances in the labra included surface irregularity, fissures and cleft formation. MR imaging correctly identified the severity of chondral abnormality in 24 of 27 hips (89%) when compared with arthroscopic findings.Conclusions MR imaging demonstrates an elongated labrum, focal intra-substance signal change and irregularity and fissuring of the margins in patients with acetabular dysplasia. Abnormality is also identified at the labral chondral transitional zone, where fissuring, focal clefts, chondral deficiency and subchondral cyst formation may be apparent. A high-resolution, non-arthrographic technique can provide an accurate preoperative assessment and evaluate the presence of premature osteoarthritis.     

Arthrography of painful hips following arthroplasty: digital versus plain film subtraction

Digital and manual subtraction images obtained during the arthrographic evaluation of 78 painful hip prostheses were reviewed retrospectively. Revision arthroplasty was performed in 53 of these cases, and the arthrographic and surgical findings were correlated. The digital and manual subtraction images were evaluated without knowledge of the surgical results using established criteria for component loosening. Digital subtraction arthrography of the femoral component demonstrated a 96% sensitivity and 100% specificity for the diagnosis of component loosening. Sensitivity and specificity for acetabular component loosening were 83% and 80%, respectively. Plain film subtraction of the femoral component demonstrated a 79% sensitivity and 100% specificity; the sensitivity and specificity for the acetabular component were 75% and 80%, respectively. The difference between detection of femoral component loosening on digital as opposed to manual subtraction images was statistically significant (P<0.05). This study demonstrates that digital subtraction improves the evaluation of femoral component loosening in painful hip prostheses.     

成人髋臼发育不良性骨关节病的影像学表现

目的　探讨成人髋臼发育不良性骨关节病的影像学表现。方法　对 5 1例 87个髋成人髋臼发育不良的影像资料进行回顾性分析。患者除男性 4例外均为女性 ,年龄 2 2～ 78岁 ,平均42 6岁。所有患者均摄有标准的骨盆前后位X线片 ,18例行CT扫描 ,10例行MR扫描。结果　 87个发育不良髋臼的主要X线改变为髋臼浅小 ,倾斜度增加和对股骨头覆盖不全。测量中心边缘角 (CE)为 - 10°～ 3 0°,平均 12 9°。测量髋臼指数为 3 5°～ 67° ,平均 45 3°。其中 75髋 (84 2 % )有继发性骨关节炎 ,5 4髋 (62 1% )出现髋臼或股骨头负重区软骨下囊性变 19髋 ,伴有髋关节半脱位。CT和MRI发现平片不能显示的小囊变和股骨头向前移位者分别为 13髋和 10髋。结论　髋臼或股骨头囊样病变是髋臼发育不良性骨关节病的常见表现 ,CT或MRI能显示其早期征象     

游离神经末梢和感觉小体溃变过程的实验研究

目的：研究神经损伤后，感觉神经末梢的溃变过程。方法：选用恒河猴9只，除拇 指外随机选择20个手指，其中15指切断指神经，另外5指为正常的和指，不进行任何手术，于术后2，4，12，20，32和48周采用镀银染色技术对神经末梢进行形态学观察。结果：失神经后2周，游离神经末梢和感觉小体开始溃变，20周，游离神经末梢结构消失，48周，触角小体，环层小体全部失神经支配。结论周围神经损伤后，原有神经成分首先溃变，非神经成分随之溃变，最终被胶原替代。