Classification Of Acetabular Fractures Research Articles

Classification of Common Acetabular Fractures: Radiographic and CT Appearances

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. 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.

Interobserver Agreement for Letournel Acetabular Fracture Classification with Multidetector CT: Are Standard Judet Radiographs Necessary?

To retrospectively evaluate interobserver agreement for Letournel acetabular fracture classification with radiography alone and multidetector computed tomography (CT) alone and to retrospectively assess whether standard Judet views lead to a change in the classification. Institutional review board approval was obtained; informed consent was not required for this HIPAA-compliant study, which included 101 imaging studies performed in 99 patients (78 male, 21 female; mean age, 43 years; age range, 15-86 years) with acetabular fractures. Two musculoskeletal radiologists independently classified the fractures with radiography alone and multidetector CT alone. Multiplanar reformatted and three-dimensional (3D) CT images were reviewed at a computer workstation. Readers were shown radiographs at the end of multidetector CT image reading to see if this would change the multidetector CT-based classification. kappa Values were calculated to assess interobserver agreement. For surgically treated patients, the McNemar test was used to compare the accuracy of readers' classifications. The reference standard was a combination of preoperative radiographic and multidetector CT image findings and intraoperative findings. Interobserver agreement was moderate (kappa = 0.42) with radiography and substantial (kappa = 0.70) with multidetector CT. Multidetector CT classification was changed in two cases (one case for each reader) after standard Judet views were added. In 73 surgically treated patients, agreement with the surgeons' classification was higher with multidetector CT than with radiography (P < .01 for one reader, P = .06 for the other reader). There is substantial interobserver agreement for Letournel acetabular fracture classification with multiplanar reformatted and 3D multidetector CT images. Standard Judet pelvic radiographs add little information for changing the multidetector CT classification.

Reprodutibilidade da classificação de Tile para fraturas do acetábulo

Classificar corretamente as fraturas acetabulares é crucial para bom planejamento pré-operatório e para redução cirúrgica eficiente. Entretanto, para cumprir seus objetivos, qualquer sistema de classificação deve ser simples e reprodutível. O objetivo deste artigo é avaliar a reprodutibilidade interobservador da classificação de Tile para fraturas do acetábulo. Foram utilizadas 30 imagens radiográficas de 10 fraturas acetabulares nas incidências de Judet, analisadas por 10 observadores, sendo cinco especialistas em cirurgia de quadril e cinco residentes do terceiro ano de ortopedia. A concordância global obtida foi de 72,44% com Kappa (K) = 0,52 (0,48 entre residentes e 0,57 entre especialistas). Conclui-se que a classificação de Tile para fraturas acetabulares apresenta moderada concordância interobservador, não havendo diferença estatisticamente significante entre residentes e especialistas.

CT-Based Acetabular Fracture Classification

CT-Based Acetabular Fracture ClassificationSteven A. OlsonAudio Available | Share

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.

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

The objective of this investigation was to provide a new CT-based classification of acetabular fractures. 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. 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. 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.

CT of pelvic fractures

Although magnetic resonance imaging has become the dominant modality for cross-sectional musculo-skeletal imaging, the widespread availability, speed, and versatility of computed tomography (CT) continue to make it a mainstay of emergency room (ER) diagnostic imaging. Pelvic ring and acetabular fractures occur as the result of significant trauma secondary to either a motor vehicle accident or a high-velocity fall. These injuries are correlated with significant morbidity and mortality, both from the complications of pelvic ring fractures and from commonly associated injuries. The most commonly used classification of pelvic and acetabular fractures has been based on conventional radiographs that are, in the majority of cases, sufficient to determine the type of injury. However, because of the complexity of pelvic and acetabular fractures, precise pathological anatomy is not easily demonstrated by routine radiographs and in many cases details of fractures are not visible. Moreover, the insufficient co-operation of the patient or the difficulty of maintaining special positions can be overcome by using computed tomography. Spiral computed tomography provides information regarding the extent of the fractures and is complementary to radiography for ascertaining the spatial arrangement of fracture fragments. Spiral computed tomography is an effective tool for understanding complex fracture patterns, particularly when combined with multi-planar reconstruction two-dimensional (MPR 2D) reformatted images or three-dimensional images (3D) images. Including these techniques of reconstruction in routine pelvic imaging protocols can change management in a significant number of cases. Subtle fractures, particularly those oriented in the axial plane, are better seen on MPR images or 3D volume-rendered images. Complex injuries can be better demonstrated with 3D volume-rendered images, and complicated spatial information about the relative positions of fracture fragments can be easily demonstrated to the orthopaedic surgeons. The use of intravenous (i.v.) contrast material allows simultaneous evaluation of osseous and vascular structures within the affected area. Postoperative studies in patients with orthopaedic hardware also benefit from volume-rendered imaging. Volume rendering eliminates most streak artifact and produces high-quality images on which the relationships among hardware, bones, and bone fragments are well demonstrated.

LETOURNEL CLASSIFICATION FOR ACETABULAR FRACTURES

A fracture classification system enables communication among surgeons and provides guidelines for treatment as well as some estimate of prognosis. Thus, the system should be anatomically meaningful and reliable. The purpose of this study was to assess the interobserver and intraobserver reliability of Letournel's acetabular fracture classification and the effect of computed tomography on its reliability. Plain radiographs (anteroposterior and Judet views) and axial computed tomography scans were randomly chosen from an acetabular fracture database, with at least five cases of each fracture type and eight of the most common types. The study involved three groups of three orthopaedic surgeons: (1) surgeons who had studied under Letournel, (2) surgeons who specialized in acetabular fracture surgery, and (3) general trauma surgeons. Each observer read the radiographs twice, and at each session the fractures were classified first on the basis of the radiographs only and then in combination with the computed tomography scan. Observer agreement was then assessed with the unweighted kappa coefficient (kappa). We also calculated the frequency with which the observers agreed with the diagnosis made intraoperatively by the treating orthopaedic surgeon. The interobserver reliability without and with computed tomography during the first session was 0.70 and 0.74, respectively, for group 1, 0.71 and 0.69 for group 2, and 0.51 and 0.51 for group 3. The results of the second session were similar. When the two sessions were compared, intraobserver reliability without and with computed tomography was 0.80 and 0.83 for group 1, 0.80 and 0.80 for group 2, and 0.64 and 0.69 for group 3. The overall agreement of the radiographic observation with the fracture pattern observed at surgery was 74%. Letournel's acetabular classification with use of plain radiographs with or without supplemental computed tomography scans has substantial reliability (kappa > 0.7) when used by surgeons who have been taught how to interpret the images or by those who treat acetabular fractures on a regular basis. The value of computed tomography scans in the evaluation of acetabular fractures has been well established for the identification of loose bodies and articular impaction; however, they do not appear to be essential for the classification of acetabular fractures.

Improving reliability in the classification of fractures of the acetabulum.

Plain radiographs of the pelvis are routinely used in the initial assessment of patients with suspected fractures of the acetabulum. It is necessary for orthopaedic resident trainees, emergency physicians as well as orthopaedic surgeons who infrequently treat trauma patients to be able to describe these fracture patterns reliably to traumatologist orthopaedic surgeons who ultimately take over the patient care. Our purpose was two-fold: (1) to determine the reliability of the component parts of the Letournel classification of acetabular fractures involving six anteroposterior (AP) radiographic lines, and (2) to examine whether the addition of oblique radiograph views (Judet views) would improve the reliability. Thirty sets of AP and oblique radiographs (Judet views) of the pelvis were selected from a hospital database to represent various types of acetabular fractures. Six reviewers (three orthopaedic trainees and three community orthopaedic surgeons) independently reviewed the radiographs. For each radiograph, the reviewer classified the acetabular fracture according to the Letournel classification. In addition, each reviewer utilized a simplified classification scheme using six radiographic lines on the AP pelvic radiograph. Interobserver reliabilities among reviewers were reported along with the intraclass correlation coefficient (ICC) and kappa values. Agreement for the Letournel classification increased with increasing physician experience (trainees ICC=-0.14 and community surgeons ICC=0.56). Interobserver reliability between trainees and community surgeons improved when the six radiographic lines were used (range kappa=0.09-0.89). The oblique pelvic radiographs (Judet views) did not significantly improve reliability among physicians. In this study we report the following: (1) the reliability of the Letournel classification improves with level of training, (2) physicians with less experience with acetabular fractures have significantly better agreement in identifying fractures using the six radiographic lines on the AP film than the Letournel classification, and (3) agreement among the reviewers for the AP pelvic radiograph is not improved with additional oblique (Judet) views.

3D CT Versus Axial Helical CT Versus Conventional Tomography in the Classification of Acetabular Fractures: A ROC Analysis

AIM: To assess the diagnostic power of three-dimensional computed tomography (3D CT), axial helical computed tomography (CT) and conventional tomography in the classification of acetabular fractures by interdisciplinary review. MATERIALS AND METHODS: Receiver operating characteristics (ROCs) were assessed for two radiologists and two surgeons blinded to the presence of acetabular fractures in an animal model (a total of 62 porcine hips, 40 of them with artificial acetabular fractures). Main target parameter was the diagnostic accuracy in the classification of the artificial fractures following Judet et al. RESULTS: ROC analysis for radiologists showed Az values of 0·83 for 3D CT, 0·81 for axial helical CT, and 0·78 for conventional tomography; differences between the three techniques were not significant (P=0·46–0·73). Az values for the surgeons were 0·87 for 3D CT, 0·68 for axial helical CT, and 0·60 for conventional tomography; 3D CT was significantly better than axial helical CT (P=0·01) and conventional tomography (P=0·001). The differences between axial helical CT and conventional tomography were not significant (P=0·37). CONCLUSION: Acetabular fractures are best classified by 3D CT, followed by axial helical CT and conventional tomography when assessed by surgeons. 3D CT did not provide any additional significant benefit in the classification performed by radiologists. Kickuth, R. et al. (2002). Clinical Radiology57, 140–145.

Classification of acetabular fractures. A systematic analysis of the relevance of computed tomography

The classification of acetabular fractures and especially the diagnosis of additional lesions can be misleading, when the personal experience is limited and the decisions are based only on conventional radiographs. The introduction of Spiral-CT with multiplanar reformations and 3-D views has improved the quality of visualization. Due to their higher costs, the need of these additional diagnostic tools is frequently questioned. This paper discusses the relevance of plain radiographs, 2-D-CTs, 3-D-CTs and Femursubtraction-CTs (FsCT) for the classification of acetabular fractures, based on a controlled study. Methods: Thirty physicians with different levels of experience in acetabular surgery were divided in three groups of 10 each: group I comprised residents without operative experience in acetabular surgery, group II was physicians with 3–10 years of operative experience, and group III was experts in acetabular surgery. A total of 10 complete radiographic cases of high quality providing all levels of preoperative diagnostics (plain radiographs, 2-D-CT, CT with multiplanar reformation, 3-D-CT, Fs-CT) of different acetabular fracture types were prepared. The task for each candidate was to classify the fracture according to Letournel and to identify all additional injuries within the hip joint (e. g. marginal impaction, head fractures, etc.). The different diagnostic “levels” could be ordered stepwise according to personal need and no time limit was given. The case was finished when the candidate presented his final diagnosis. The use of the different radiographs, the preliminary diagnosis, the changes in diagnosis, and the final decisions were recorded. These findings were correlated with the different levels of experience and against a “consensus classification” which was generated by thorough discussion, and the use of intraoperative information and postoperative radiographs not accessible to the candidates. Results: The “correct” fracture classification based on plain radiographs was: group I, 11 %; group II, 32 %; group III, 61 %. Based on 2-D-CT a “correct” diagnosis was reached by 30 % in group I, by 55 % in group II, and by 76 % in group III. With consideration of the “transient forms” in acetabular fractures based on Letournel and the 3-D-CT used mainly by group I, the rate of “correct” classifications rose to 65 % in group I, 64 % in group II and 83 % in group III. The modifiers were diagnosed “correctly” in group I by 37 %, in group II by 56 %, and in group III by 73 %. The use of the 3-D-CT and especially the Fs-CT by group I resulted in an improvement in the rate of correct classifications to 61 %, whereas in group II the Fs-Ct was used only exceptionally. The 2-D-CT was the basis for the diagnosis of the additional lesions in acetabular fractures within all groups resulting in 73 % complete diagnoses in group III. This study showed the importance of CT for the exact analysis and classification of acetabular fractures. In particular, the secondary reformations in CT and the 3-D-views dramatically improved the rate of “correct” classifications in the group of surgeons with limited personal experience in acetabular surgery. This allows the less experienced an acceptable level of “correct” diagnoses, so that the treatment options can be weighed correctly. Among the “experts” a rate of divergent classifcations of approximately 20 % was observed, especially in “transient” forms of acetabular fractures.

Fractures of the Acetabulum After a Total Hip Arthroplasty

Summary: This article outlines the classification and treatment of periprosthetic acetabular fractures. Although these fractures are uncommon, they may be on the rise with the use of cementless press-fit components and as more components remain in service for long periods of time with development of bone loss associated with component loosening.

Acetabular fractures: A systematic approach to classification

The classification of acetabular fractures is important for preoperative planning; interpretation of imaging studies, however, is often difficult. Plain radiography is the primary method for evaluation of these injuries, and computed tomography is now commonplace for the preoperative classification of patients with acetabular fractures. We have developed a systematic approach that aids in the classification of these fractures.

Classification and evaluation of acetabular fractures

Classification and evaluation of acetabular fractures

Complex Acetabular Fractures

Open surgery is recommended for complex fractures whenever primary conservative treatment fails to satisfactorily reduce the femoral head and the weight-bearing dome of the acetabulum. Surgical exposure has been a major problem in attempting open reduction of these fractures. The classification of acetabular fractures noted above is a useful guide to the indications for open operation. A transtrochanteric lateral approach provides a good extra and intraarticular access to the acetabulum. The excellent clinical results achieved in 28 cases of complex acetabular fractures with a mean of 5.7 year follow-up testify to the value of this approach.