Classification of common acetabular fractures: radiographic and CT appearances

OBJECTIVE: Accurate characterization of acetabular fractures can be difficult because of the complex acetabular anatomy and the many fracture patterns. In this article, the five most common acetabular fractures are reviewed: both-column, T-shaped, transverse, transverse with posterior wall, and isolated posterior wall. Fracture patterns on radiography are correlated with CT, including multiplanar reconstruction and 3D surface rendering. CONCLUSION: In the evaluation of the five most common acetabular fractures, assessment of the obturator ring, followed by the iliopectineal and ilioischial lines and iliac wing, for fracture allows accurate classification. CT is helpful in understanding the various fracture patterns.     

髋臼骨折CT与X线平片检查比较

目的探讨CT与X线平片检查在髋臼骨折诊断中的临床应用价值。方法对照分析18例髋臼骨折CT、X线平片及临床治疗随访资料。结果18例髋臼骨折中前壁骨折4例,前柱骨折4例,后壁骨折2例,后柱骨折2例,复杂骨折6例。伴有盆腔内软组织肿胀11例。其中X线平片误漏诊4例。CT检出骨碎片27块,X线平片检出12块,其中关节腔内游离骨碎片CT检出17块,X线平片检出4块。股骨头脱位7例,伴股骨头骨折3例,其中X线平片漏诊1例。结论CT显示关节腔内碎骨片,确定骨折分型及了解盆腔软组织受损情况优于X线平片检查。     

Acetabular fractures revisited: part 2, a new CT-based classification

OBJECTIVE: The objective of this investigation was to provide a new CT-based classification of acetabular fractures. MATERIALS AND METHODS: The axial CT scans of 112 randomly selected acetabular fractures in patients admitted to a level 1 trauma center between January 1998 and December 2000 were analyzed by an experienced orthopedic trauma surgeon and two experienced emergency radiologists. When available, 3D reformatted images were analyzed as well. The fracture pattern for each acetabular fracture, with respect to column walls and extension beyond the acetabulum, when present, was recorded. Fracture comminution was not a defining characteristic. RESULTS: Analysis of the 112 acetabular fracture patterns showed that each fracture fell into one of four broad categories. Category 0 included wall fractures only. Category I included acetabular fractures limited to a single (anterior or posterior) column. Category II fractures included those involving both the anterior and posterior columns; category II fractures were further subdivided into those with no fracture extension beyond the acetabulum, those with superior or inferior extension, and those with both superior and inferior extensions beyond the acetabulum. Category III fractures included only the "floating" acetabulum, which is defined as an acetabular fracture in which the acetabulum is separated from the axial skeleton both anteriorly and posteriorly. CONCLUSION: The axial CT display of acetabular fracture patterns provides a basis for a classification of acetabular fractures that is simple, unambiguous, readily understood by both radiologists and orthopedic surgeons and provides clear direction for both diagnosis and surgical treatment planning. Category and subcategory fracture specificity creates a mechanism for intra- and interdepartmental postoperative assessment of any of the individual acetabular fracture types.     

Association of femoral head and acetabular fractures on computerized tomography: correlation with the Judet-Letournel classification

Purpose

Tha aims of this study were to identify the incidence of femoral head fractures in the setting of acetabular fractures and to determine the relationship between acetabular fracture pattern, the degree of acetabular fracture displacement, and the incidence of femoral head fractures.

Materials and methods

This is a retrospective cross-sectional study of 274 patients with 300 acetabular fractures diagnosed on pelvic CT. Acetabular fractures were categorized using the Judet-Letournel classification system.

Results

Femoral head fractures were present in 18.0% of acetabular fractures. Fracture patterns with a posterior wall component had a very high (56.3%) incidence of femoral head fracture. Anterior column and anterior column with posterior hemitransverse fractures have a very low (3.4%) incidence of femoral head fracture. Anterior hip dislocation had a 66.7% incidence of femoral head fracture, while posterior dislocation had a 71.9% incidence. Acetabular fractures displaced by more than 5 mm had a 26.9% incidence of femoral head fracture, while acetabular fracture displaced less than 5 mm had only 4.2% incidence of femoral head fracture.

Conclusion

Femoral head fractures are a very common associated finding in patients presenting with acetabular fractures. In patients with a posterior wall component of the fracture or associated hip dislocation, a femoral head fracture is more likely than not present. Conversely, in acetabular fractures with less than 5 mm displacement or anterior column fractures without posterior acetabular involvement, femoral head fractures are very unlikely in the absence of a dislocation event.

     

CT detection of cortical fracture of the femoral head associated with posterior hip dislocation

Posterior dislocation of the femoral head is a common injury in automobile accidents and is frequently associated with fractures of the posterior acetabular rim. Fractures of the anterior cortex of the femoral head have not been described. One hundred sixty-four cases of posterior hip dislocation presenting consecutively to our shock trauma unit and emergency department during a 3-year period were evaluated with plain film radiology and CT. In 21 cases (13%), CT showed an anterior cortical fracture of the femoral head that could not be seen on plain radiographs. This injury is similar to the Hill-Sachs lesion of the humerus that results from anterior dislocation. The anterior cortical fracture was associated with fractures of the posterior acetabulum in 18 cases (86%). The anterior fracture is caused by impaction of the anterior femoral head against the posterior acetabular rim at the time of dislocation. We conclude that anterior cortical fracture of the femoral head is a common accompaniment to posterior acetabular dislocation.     

Evaluation of acetabular fractures with two- and three-dimensional CT.

The authors applied a widely used radiographic system of classifying acetabular fractures to axial computed tomographic (CT) scans and three-dimensional reconstructions in over 100 cases. In the classification system, fractures are analyzed according to the extent of involvement of two acetabular columns--the posterior and the anterior. To provide a better understanding of the CT anatomy of the acetabulum, the authors defined the boundaries of the columns on axial CT scans. They illustrated the most common fractures (posterior wall, transverse, transverse with posterior wall, and both columns) with radiographs, axial CT scans, and three-dimensional reconstructions. Axial CT scans readily demonstrated the fractures and presence of intraarticular fragments. Three-dimensional images helped in understanding the precise plane of the fracture, the degree of disruption of the articular surface, and spatial relationships of fragments. Although present three-dimensional CT is not without limitations, the authors believe that the technique is valuable and that, in their experience, it has facilitated preoperative planning.     

CT of acetabular fractures: analysis of fracture patterns

Thirty-one consecutive patients who sustained acetabular fracture or posterior femoral head dislocations were examined by computed tomography (CT). By analysis of closely spaced, thin CT images, it was possible to characterize the three-dimensional nature of these injuries. Traditional classification into anterior column, posterior column, and complex two-column fractures was facilitated. CT was especially useful in evaluation of the two-column fractures in which unique information concerning the configuration of the fracture, integrity of the acetabular dome and quadrilateral surface, and identification of the stable fragment was obtained. Surprisingly constant fracture patterns were identified. CT was also useful in determination of presence or absence of loose bodies in the joint and in evaluation of the femoral head and sacroiliac joint in all types of fracture.     

螺旋CT三维和多平面重建在髋臼骨折中的应用

目的：探讨螺旋CT三维（3D）和多平面重建（MPR）在髋臼骨折中的临床应用价值。方法：27例髋臼骨折的病人先经营骨盆螺旋CT薄层扫描，并在工作站上作髋臼三维和多平面重建。注重观察髋臼骨折的以及CT表现特征。结果：27例病人共计31个髋臼骨折。除1个T形骨折用三维和多平面重建判断为横行骨折外，其余30个骨折轴位CT、三给和多平面重建均显示。三维和多平面重建能更直观的显示病变的具体情况。结论“螺旋CT三维和多平面重建是轴位CT扫描的有价值的补充手段，在髋臼骨折中有很高的应用价值。     

螺旋CT三维重建(SSD、VRT)在髋臼骨折中的临床诊断价值:兼与X线、2DCT、MPR比较

目的　探讨螺旋CT三维表面遮盖法重建 (SSD)及容积重建技术 (VRT)显示髋臼骨折的诊断价值。方法　使用SIEMENSPLUS4螺旋CT机对 3 0例髋臼损伤患者进行扫描 ,在SIEMENS工作站进行SSD及VRT重建观察损伤细节 ,并与X线平片、二维CT(2DCT)、MPR比较。结果　 3 0例髋臼骨折 ,2DCT、MPR、VRT检查共发现了 169处骨折 ,X线发现 13 3处骨折 ,检出率是 78.7%。SSD发现 15 8处 ,检出率 93 .5 %。根据 2DCT扫描结果 ,经统计学分析 ,SSD、VRT检出骨折创伤量与X线、2DCT、MPR三者无显著性差异。3 0例髋臼骨折根据 2DCT按AO分类法分类 ,并经MPR、3DCT重建证实其分类 ,其中 2 2例经手术确诊 ,X线误诊 7例。 3DCT获得了髋臼骨折最直观、全面的图像。 12例进行了术后的 3DCT重建 ,VRT立体显示手术后骨盆及内固定物的形态、结构 ,SSD重建有时不能分辨内固定物和骨盆的形态、结构。结论　螺旋CTSSD及VRT是诊断髋臼骨折的有效手段 ,3DCT在骨盆及髋臼骨折分型中有重要的作用 ,对复杂性髋臼骨折的诊断应作为首选。VRT对术后固定针的位置及复位效果的判断有较高的价值     

The role of 3D CT in the assessment of acetabular fractures.

A total of 16 patients with acetabular fractures were evaluated by plain radiography, axial computed tomography (CT) and three dimensional (3D) CT. It was possible to classify the fracture type in each case from the plain radiographs alone. Axial CT gave additional detail in certain areas, notably the region of the teardrop, the obturator foramen and the acetabular roof. Intra-articular and impacted roof fragments and associated soft tissue injuries were also shown. 3D CT provided the best and most easily interpreted overall assessment of the fractures. In addition to projections equivalent to the plain radiographs, two other views were of particular clinical value in demonstrating surgically inaccessible areas, namely the view of the pelvis from above and the view of the inner aspect of the fractured hemipelvis. However, fracture lines demonstrated on plain radiographs and axial CT were not always apparent on the 3D CT scans. Although 3D CT is a valuable addition to the imaging of acetabular fractures, it is not a substitute for good quality plain radiography and analysis of the axial CT images.     

Occult central fractures of the acetabulum.

Four cases of occult central acetabular fractures are presented. The oblique plane of the fracture line and the lack of displacement of the fracture fragments made the fractures difficult of impossible to visualize in the anteroposterior projection. The posterior oblique projection placed the fracture line perpendicular to the x-ray beam and, therefore, evident on the resultant roentgenogram. In the 3 cases in which this view was obtained, the fracture was disclosed. In the fourth case the fracture was demonstrated by tomography. In order to improve the roentgenographic assessment of pelvic trauma, consideration should be given to obtaining posterior oblique views of the pelvis as a matter of routine.     

Ⅰ期全髋关节置换治疗髋臼骨折

目的 探讨髋臼骨折后Ⅰ期全髋关节置换(total hip arthroplasty,THA)的手术适应证和手术方法,观察其临床疗效.方法 对11例髋臼骨折患者行Ⅰ期THA.其中前柱骨折3例,后壁骨折1例,后柱骨折2例,后柱合并后壁骨折2例,横形骨折1例,横形合并后壁骨折1例,两柱骨折1例.伤后8～37 d(平均24 d)接受THA.对新鲜髋臼骨折患者,先用重建钢板或螺钉固定骨折以恢复髋臼肇的形态,将切下的股骨头制成颗粒状或块状植于髋臼内后安置臼杯.陈旧性髋臼骨折有节段性髋臼骨缺损者,将切下的股骨头制成大块状进行髋臼内结构性植骨后再安置臼杯.结果 术后3个月完全负重,无人工关节脱位.随访时间6～45个月,平均28个月.Harris评分平均78分.髋关节屈伸平均活动度为95°.X线片示1例出现髋臼松动及骨溶解征象.结论 髋臼骨折移位明显,关节软骨面损伤严重,错过了手术复位时机,可以Ⅰ期行THA.如能创造稳定的髋臼杯结构,近期临床效果满意.     

髋臼骨折的CT与X线平片诊断比较

目的:比较CT与X线平片对髋臼诊断的价值。材料和方法:18例髋臼骨折病人,全部接受CT扫描确诊,其中,14例是先经X线平片诊断为骨折的,4例X线检查未发现骨折线。分析比较CT与X线平片的表现。结果:经CT扫描发现的5例后壁骨折,X线漏诊2例;1例股骨头前缘皮质凹陷骨折、7例髋臼腔内游离碎片和10例髋关节周围软组织肿胀,X线均未能发现。结论:CT可准确显示骨折线的数目和走行方向,显示骨折类型和关节面损伤程度,以及关节腔内有无骨折碎片等情况,为临床治疗提供比X线平片更可靠的信息。     

手术治疗髋臼骨折34例临床分析

目的：探讨髋臼骨折的手术方法和观察临床效果。方法：对2005-06～2010-06间共手术治疗髋臼骨折34例,采用Kocher-Langenbeck入路和髂腹股沟入路进行回顾性分析。结果：解剖复位28例,复位满意4例,复位不满意2例。全部病例获随访6～27月,平均10.2月,临床效果优良率为94.12%（32/34）。结论：手术是治疗髋臼骨折的有效方法,正确的手术入路选择、骨折解剖复位、稳定的内固定及早期功能锻炼是治疗的关键。     

Computed tomography in acetabular trauma

In a retrospective study of 16 acetabular fractures computed tomography (CT) clarified the type and extent of the injury. Computed tomography demonstrated intra-articular fragments of varying size in seven out of eight patients with fractures of the posterior acetabular margin. Abnormalities of the femoral head were also shown in six patients and the possible aetiology of these is discussed. The additional information provided by CT is likely to help in the management of patients with acetabular injuries.     

复合髋臼骨折手术中后方入路的特点和选择

目的探讨后方入路(Kocher-Langenbeck,K-L)在治疗复合髋臼骨折中的特点和选择指征。方法自1994年10月～2010年1月,通过后方入路手术治疗59例复合髋臼骨折,对患者手术过程、术后复位情况和并发症进行随访评价。结果平均手术时间105分钟,平均出血量480m l,平均输血2U;解剖复位31例,良好复位17例,复位差11例;发生异位骨化11例。结论在复合髋臼骨折中,后柱+后壁、横断+后壁、部分T型和前方伴后方横形骨折,甚至少量双柱骨折可经后方入路完成复位和固定,手术创伤小,复位情况良好,并发症发生率低。     

Arthroscopic reduction and internal fixation of acetabular fractures

Arthroscopic reduction and screw fixation of acetabular fractures have not been reported. In this case report, arthroscopic treatment for acetabular fracture is reported for two patients. A 49-year-old man diagnosed with acetabular posterior wall fracture was treated by arthroscopic reduction and fixation using two screws. A 20-year-old woman who diagnosed with anterior column fracture was fixed using a screw using the arthroscopic technique prior to open reduction and internal fixation in the iliac bone fracture. Arthroscopic reduction and fixation in some case of acetabular fracture could be good indication with additional advantages of joint debridement and loose body removal. Level of evidence V.     

The "communication line" suggests occult posterior malleolar fracture associated with a spiral tibial shaft fracture

Objectives

To demonstrate radiographical characteristics of the relationship between distal spiral tibial shaft fractures and associated occult posterior malleolar fractures (PMF) that confirmed by CT and MRI.

Materials and methods

X-rays for a ninety-six patients with spiral tibia fracture and associated PMF were reviewed. All patients additionally had an ankle CT. Patients with a negative CT scans underwent an ankle MRI. Radiographic observations included fracture location, characteristics, and a presence of a fracture line between the two injuries.

Results

The spiral tibia fracture line was contiguous with PMF in 89 of 96 cases after evaluation with the CT and MRI. The line connecting the two injuries, which occurs between the medial inferior apex of the spiral tibia fracture line and the posterior superior apex of the PMF was identified as the “communication line”. In 47 of the 89 conjunction fractures, the “communication line” was detectable preoperatively and in 12 cases postoperatively by anteroposterior radiograph. By using the CT and MRI scans, we found that no “communication line” was present in only 7 cases.

Conclusion

It is important to understand the nature of the association between distal spiral tibial shaft fractures and occult posterior malleolar fractures for optimal stabilization of the fracture and for appropriate rehabilitation. The “communication line” is a useful diagnostic clue for early recognition the occult PMF and alerts a closer evaluation of the lateral view and further CT examination.     

Acetabular fractures revisited: a new CT-based classification

The objective of this investigation is to provide a new CT-based classification of acetabular fractures. The axial CT scans of 112 randomly selected acetabular fracture patients admitted to a Level 1 trauma center between January 1998 and December 2000 were analyzed by an experienced orthopedic trauma surgeon and two experienced emergency radiologists. When available, 3D reformatted images were analyzed as well. The fracture pattern for each acetabular fracture with respect to column(s) wall(s) and extension superiorly and/or inferiorly from the acetabulum, when present, was recorded. Fracture comminution was not a defining characteristic. Analysis of the acetabular fracture patterns showed that each fracture fell into one of four broad categories: Category 0--wall only; Category 1--single column; Category 2--both columns, with extension subcategories of (A) no extension, (B) superior extension only, (C) inferior extension only, and (D) both superior and inferior extension; and Category 3--the "floating" acetabulum. The axial CT display of acetabular fracture patterns provides a basis for a classification of acetabular fractures that is simple, unambiguous, readily understood by both radiologists and orthopedic surgeons, and provides clear direction for both diagnosis and surgical treatment planning. Category and subcategory fracture specificity creates a mechanism for intra- and interdepartmental postoperative assessment of any of the individual acetabular fracture types.