Two and three-dimensional computed tomography for the classification and management of distal humeral fractures. Evaluation of reliability and diagnostic accuracy

A Partial Frontal Fracture of the Humeral Trochlea: A Case Report

Fractures of the lower end of the humerus are uncommon but serious, potentially compromising elbow function. This article reports the case of a young patient with a fracture of the inner cheek of the humeral trochlea, resulting from a public road accident. The diagnosis was established by radiography and CT scan, confirming a displaced fracture associated with an avulsion fracture of the coronoid process. Surgical treatment was carried out with fixation of the osteochondral fragment and evacuation of the intra-articular fragments. Two months after the operation, the patient regained good joint function with a resumption of professional activity.

Artificial intelligence and computer vision in orthopaedic trauma : the why, what, and how

Artificial intelligence (AI) is, in essence, the concept of 'computer thinking', encompassing methods that train computers to perform and learn from executing certain tasks, called machine learning, and methods to build intricate computer models that both learn and adapt, called complex neural networks. Computer vision is a function of AI by which machine learning and complex neural networks can be applied to enable computers to capture, analyze, and interpret information from clinical images and visual inputs. This annotation summarizes key considerations and future perspectives concerning computer vision, questioning the need for this technology (the 'why'), the current applications (the 'what'), and the approach to unlocking its full potential (the 'how'). Cite this article: Bone Joint J 2022;104-B(8):911-914.

Coronal Shear Fractures of the Distal Humerus

Coronal shear fractures of the distal humerus are rare, frequently comminuted, and are without consensus for treatment. The aim of this paper is to review the current concepts on the diagnosis, classification, treatment options, surgical approaches, and complications of capitellar and trochlear fractures. Computed Tomography (CT) scans, along with the Dubberley classification, are extremely helpful in the decision-making process. Most of the fractures necessitate open reduction and internal fixation, although elbow arthroplasty is an option for comminuted fractures in the elderly low-demand patient. Stiffness is the most common complication after fixation, although reoperation is infrequent.

Coronal shear fractures of the distal humerus managed according to the Modified Dubberley Classification System

BACKGROUND

Coronal shear fractures of the capitellum and trochlea are relatively uncommon and can be challenging to treat because of variable articular comminution and poor bone stock. Classification is valuable to help guide surgical decision making and prognosis. The aim of this study was to present a large series of coronal shear fractures treated according to the Modified Dubberley Classification System (MDCS).

METHODS

Forty-five patients with a coronal shear fracture were followed up (12-93 months, mean: 28 months) after surgical intervention. Fractures were classified according to the MDCS by 3 observers, and outcome data collected included Oxford elbow score (OES), visual analog pain score (VAS), range of motion, complications, and radiographic findings.

RESULTS

There were 10 type 1, 12 type 2, 8 type 3, and 15 type 4 fractures. There were 26 subtype B fractures (posterior comminution). A total of 37 patients underwent open reduction and internal fixation (ORIF) and 8 primary arthroplasty. The median OES and VAS were 43(16-48) and 2 (0-9), respectively. Median flexion extension arc was 125° (range, 70°-140°). There was no significant difference in OES, VAS, or range of motion according to fracture type (types 1-4), subtype (type a or b), or treatment method (arthroplasty vs. ORIF). The overall complication and reoperation rates were 31% and 33%, respectively. A total of 75% of complications occurred in type 3 and 4 fractures, and there was a nonsignificant trend toward higher complication rate in type B fractures than type A fractures (34% vs. 16%, P = .19). Patients with a type B fracture who underwent screw-only fixation had a significantly lower OES and higher complication rate compared with when they had combined plating with screws (OES, P = .03; complications P = .04) and compared with when an arthroplasty was performed (OES, P = .05; complications P = .04).

CONCLUSION

Consistently good outcomes can be achieved by classification and management according to the MDCS. It is recommended that type B fractures undergo combined plate and screw fixation and that type 4 fractures should be considered for arthroplasty because of the higher risk of complications with ORIF.

Assessment of Usefulness of CT Scan in AO Classification of Intertrochanteric Fractures: A Prospective Observational Study

OBJECTIVE

The sliding hip screw (SHS) is the gold standard for the management of stable intertrochanteric (IT) fractures. However, intramedullary implants are now being increasingly used for management of unstable IT fractures especially those with a compromised or vulnerable lateral wall. Therefore, accurate classification of fracture is important to ensure proper surgical planning and choice of implant. The AO classification for IT fractures is based on plain radiographs alone and many authors have reported it to have poor inter- and intra-observer agreement. Therefore, the objectives of the study were to assess the improvement in inter- and intra-observer agreement of the AO classification after addition of CT scan to plain radiographs, to assess the change in pattern of AO classification on addition of CT scan to plain radiographs and to assess percentage of times, stable lateral wall seen on plain radiographs is classified as unstable or broken on CT scans.

METHOD

Fifty-four patients of intertrochanteric fracture were included in study. Plain radiographs of patients were shown to three orthopedic surgeons. They were asked to document the AO classification of the fracture, and comment on the integrity of the lateral wall. Then, CT scans with 3D reconstructions of the same patients were provided along with the radiographs and they were asked to classify the fracture again. Inter- and intra-observer agreement of the AO classification based on plain radiographs alone and once CT scan with 3D reconstruction was added to the plain radiographs was determined using Kappa coefficients. Pattern of change in classification on addition of CT scan to plain radiographs was also assessed.

RESULT

The mean kappa value for inter- and intra-observer agreement for AO classification on plain radiographs alone were 0.58 (moderate) and 0.66 (substantial), respectively. Upon addition of CT scan to plain radiographs, both improved to 0.70 (substantial) and 0.77 (substantial), respectively. The AO classification of the fracture changed 28.70% times (93 of 324 observations) upon addition of CT scan to plain radiographs. 96.77% times (90 of 93 observations) the classification was upgraded to higher group, while it was downgraded in only 3.22% times (3 of 93). 55.91% times this change was observed in AO 31 A 2 group (52 of 93 observations). In 17.59% cases (57 of 324 observations), fractures which were classified as stable (A1.1-A2.1) on radiographs alone, were reclassified as unstable (A2.2-3.3) upon addition of CT scan to plain radiographs. In 11.4% cases (37 of 324 observations), the lateral wall was classified as vulnerable or broken on CT scans where it was classified intact on plain radiographs.

CONCLUSION

Addition of CT scans with 3D reconstructions to plain radiographs improves the intra- and inter-observer agreement of the AO classification. Addition of CT scan results in change in classification of the fracture in about one out of three cases. This most commonly happens in the AO 31 A 2 group. Most of the times, this results in the classification of fracture being upgraded. Many fractures which are initially classified as stable (A1.1-A2.1) on radiographs are reclassified as unstable (A2.2-3.3) on addition of CT scans. The lateral wall is also classified as vulnerable or broken more number of times on CT scans than plain radiographs alone. Therefore, we conclude that CT scan with 3 D reconstructions definitely helps in better pre-operative classification of intertrochanteric fractures especially in select group of fractures (AO 31 A 2) where stability and integrity of lateral wall is difficult to assess.

Coronal shear fractures of the capitellum and trochlea: interobserver variability in classifying the fracture and the need for a computed tomography scan for the correct surgical planning

Background

To determine interobserver agreement in the classification by X-rays and by computed tomography (CT) scan of the coronal shear fractures of the capitellum and trochlea as well as the agreement between these two tests.

Methods

Patients with coronal shear fractures of the capitellum who were managed at our center between January 2008 and December 2017 were included. This retrospective cohort study was carried out with the approval of the ethics committee of our institution (Nº: IIBSP-Cod-2019-02, Ref. 19/070). Clinical, radiographic, and elbow-specific outcomes, including the Mayo Elbow Performance Index, were evaluated. Three observers analyzed the preoperative X-rays from all the cases. Each one of them independently classified the fractures according to the Bryan and Morrey classification (with the modification of McKee et al). The interobserver agreement was calculated by Cohen kappa coefficient. The same methodology was used to analyze the CT scan. Thereafter, one single value was determined for each X-ray and CT scan, from the good interobserver agreements. Finally, the agreement between the global X-ray classification and the global CT scan classification was calculated using the agreement percentage and the Cohen kappa coefficient.

Results

There were 3 males and 6 females, with a mean age of 47 years (range, 18-83). The mean follow-up period was 18 months (12-40). The average Mayo Elbow Performance Index score was 85 (range, 65-100) points. The complications were nonunion in one patient (11 %), degenerative arthritis in 7 (78 %), joint step-off in 5 (55%), and heterotopic ossification in 7 (78%). The agreement analysis between the global X-ray classification and the global CT scan classification showed a 57.1% agreement, with a kappa coefficient of −0.167. These values imply the absence of agreement.

Conclusion

Our results demostrated that simple X-rays do not allow for the adequate interpretation of distal humeral coronal plane fractures. Although an acceptable interobserver agreement was found, there is no agreement when the same fractures were analyzed by CT scan. The authors routinely recommend CT scan to assess the extent of the fracture and perform surgical planning.

Coronal shear fractures of the distal humerus: Current concepts and surgical techniques

Coronal shear fractures of the distal humerus are a unique subset of distal humeral fractures which entail partial or complete articular fractures of the distal humerus without involvement of the columns. The very distal nature of these fragments, their small size and propensity for comminution render them challenging to treat surgically. The purpose of this article is to describe the classification, outcomes and surgical techniques currently used for the treatment of these fractures using the available literature and authors' clinical experience.

Does Computed Tomography Improve Reproducibility in the Classification of Transtrochanteric Fractures?

With the aging of the population, there was a significant increase in the prevalence of hip fractures, with high mortality rates, sequelae and expenses. Understanding the fracture profile and classifying it correctly is critical to define the appropriate treatment. Several radiographic classifications have been developed for transtrochanteric fractures, such as Tronzo, Evans-Jensen, AO and Boyd-Griffin, but their reproducibility is not always satisfactory. The present review aimed to elucidate whether the addition of computed tomography (CT) implies a greater reproducibility than simple radiography in the classification of transtrochanteric fractures, and whether this is a better examination to identify the fracture trait. A search was conducted in the PubMed, Lilacs, Scielo and Cochrane databases between July 2016 and June 2017, limited to the last 15 years. All retrospective, prospective and systematic reviews articles published in the English language, with evaluation of men and/or women, were considered for review. We have excluded case reports, studies that evaluated tomography or radiographs in isolation, and duplicate studies. The research presented 112 articles, of which 5 contemplated the proposed criteria. Reproducibility for the classification of transtrochanteric fractures presented variable results and was influenced by factors such as the type of classification, the use of the simplified or complete classification, the specialty of the evaluator, his experience, and the methodology proposed by the works. There are indications that there is benefit for the use of CT, especially for fractures considered unstable, but its use as a tool to ensure better reproducibility (intra- and interobserver) remains controversial and needs further studies.

Sonographic morphometry of abductor pollicis brevis: can direct contact yield images comparable with those obtained by the water bath technique?

PURPOSE

This study sought to compare ultrasound-guided measurements of the abductor pollicis brevis (APB) using the water bath technique (WBT) and the direct contact method (DM) and investigate whether the DM can reproduce the measurements that would be obtained with a non-contact method, such as the WBT.

METHODS

The APB muscles of 80 hands (40 healthy adults) were measured. The WBT was performed in a plastic container filled with water. The probe was placed adjacent to the skin surface without contact. In the DM, sonographic images were obtained with the probe and skin separated by sufficient transmission gel. The muscle thickness and cross-sectional area (CSA) were calculated with both methods. All subjects were examined three times by two examiners to estimate the inter- and intra-observer reliability. Bland-Altman analysis was performed to examine the agreement between the methods.

RESULTS

No significant differences in the thickness or CSA of the APB were found. The interclass correlation coefficients for the WBT and DM showed almost perfect intra- and inter-observer reliability (range 0.87-0.94). There was no systematic bias between the techniques in the Bland-Altman analysis.

CONCLUSION

Similar to the WBT, the DM provides measurements of the APB thickness and CSA without causing morphometric changes.

The role of the posterior bundle of the medial collateral ligament in posteromedial rotatory instability of the elbow

Aims

The aim of this study was to evaluate two hypotheses. First, that disruption of posterior bundle of the medial collateral ligament (PMCL) has to occur for the elbow to subluxate in cases of posteromedial rotatory instability (PMRI) and second, that ulnohumeral contact pressures increase after disruption of the PMCL.

Materials and Methods

Six human cadaveric elbows were prepared on a custom-designed apparatus which allowed muscle loading and passive elbow motion under gravitational varus. Joint contact pressures were measured sequentially in the intact elbow (INTACT), followed by an anteromedial subtype two coronoid fracture (COR), a lateral collateral ligament (LCL) tear (COR + LCL), and a PMCL tear (COR + LCL + PMCL).

Results

There was no subluxation or joint incongruity in the INTACT, COR, and COR + LCL specimens. All specimens in the COR + LCL + PMCL group subluxated under gravity-varus loads. The mean articular contact pressure of the COR + LCL group was significantly higher than those in the INTACT and the COR groups. The mean articular contact pressure of the COR + LCL + PMCL group was significantly higher than that of the INTACT group, but not higher than that of the COR + LCL group.

Conclusion

In the presence of an anteromedial fracture and disruption of the LCL, the posterior bundle of the MCL has to be disrupted for gross subluxation of the elbow to occur. However, elevated joint contact pressures are seen after an anteromedial fracture and LCL disruption even in the absence of such subluxation. Cite this article: Bone Joint J 2018;100-B:1060–5.

Radiographic predictors for bone mineral loss: Cortical thickness and index of the distal femur

OBJECTIVES

Researchers continue to seek easier ways to evaluate the quality of bone and screen for osteoporosis and osteopenia. Until recently, radiographic images of various parts of the body, except the distal femur, have been reappraised in the light of dual-energy X-ray absorptiometry (DXA) findings. The incidence of osteoporotic fractures around the knee joint in the elderly continues to increase. The aim of this study was to propose two new radiographic parameters of the distal femur for the assessment of bone quality.

METHODS

Anteroposterior radiographs of the knee and bone mineral density (BMD) and T-scores from DXA scans of 361 healthy patients were prospectively analyzed. The mean cortical bone thickness (CBTavg) and the distal femoral cortex index (DFCI) were the two parameters that were proposed and measured. Intra- and interobserver reliabilities were assessed. Correlations between the BMD and T-score and these parameters were investigated and their value in the diagnosis of osteoporosis and osteopenia was evaluated.

RESULTS

The DFCI, as a ratio, had higher reliability than the CBTavg. Both showed significant correlation with BMD and T-score. When compared with DFCI, CBTavg showed better correlation and was better for predicting osteoporosis and osteopenia.

CONCLUSION

The CBTavg and DFCI are simple and reliable screening tools for the prediction of osteoporosis and osteopenia. The CBTavg is more accurate but the DFCI is easier to use in clinical practice.Cite this article: Q-F. He, H. Sun, L-Y. Shu, Y. Zhu, X-T. Xie, Y. Zhan, C-F. Luo. Radiographic predictors for bone mineral loss: Cortical thickness and index of the distal femur. Bone Joint Res 2018;7:468-475. DOI: 10.1302/2046-3758.77.BJR-2017-0332.R1.

Distal Humeral Fractures-Current Concepts

Background:

Distal humerus fractures constitute 2% of all fractures in the adult population. Although historically, these injuries have been treated non-operatively, advances in implant design and surgical technique have led to improved outcomes following operative fixation.

Methods:

A literature search was performed and the authors’ personal experiences are reported.

Results:

This review has discussed the anatomy, classifications, treatment options and surgical techniques in relation to the management of distal humeral fractures. In addition, we have discussed controversial areas including the choice of surgical approach, plate orientation, transposition of the ulnar nerve and the role of elbow arthroplasty.

Conclusion:

Distal humeral fractures are complex injuries that require a careful planned approach, when considering surgical fixation, to restore anatomy and achieve good functional outcomes.

Tension band wiring for simple olecranon fractures: evaluation of surgical technique

Background

In some settings, specific techniques for open reduction and internal fixation are preferred based on the eminence of a surgeon or professional organization. An emphasis on technical aspects of surgery that are not proved superior and vary substantially from surgeon to surgeon can be confusing for trainees. This study applied a numerical grading of the technical aspects of tension band wire (TBW) fixation for olecranon fracture; assessed the interobserver agreement of each criterion; and measured the correlation of the technical grading and objective and subjective long-term outcomes.

Materials and methods

Forty observers were invited to rate the technical aspects of TBW fixation of the olecranon on 26 post-operative radiographs. The interobserver reliability of the rating was measured using the intra-class correlation coefficient. The correlation between the rating and motion, Mayo elbow performance index, and disabilities of the arm, shoulder and hand score was tested with the Spearman’s rank correlation test.

Results

None of the figure-of-eight TBW constructs were considered perfect according to the numerical grading: the majority of observers found three deviations per fixation. The interobserver agreement was only fair for the total number of deviations and no correlation between the number of deviations and long-term objective and subjective outcome was found.

Conclusions

A rating of the technical aspects of TBW for olecranon fractures was unreliable and did not correlate with subjective and objective outcomes. Emphasis on specific technical aspects of fixation might be confusing for trainees and could distract them from the principles of effective treatment.

Level of evidence

Level IV diagnostic study.

Clinico-radiological Outcome Analysis of Parallel Plating with Perpendicular Plating in Distal Humeral Intra-articular Fractures: Prospective Randomised Study

INTRODUCTION

The distal humeral fractures are common fractures of upper limb and are difficult to treat. These fractures, if left untreated or inadequately treated, leads to poor outcomes. Management of distal humeral fractures are pertained to many controversies and one among them is position of plates.

AIM

To compare the clinical and radiological outcomes in patients with intra-articular distal humerus fractures, treated using parallel and perpendicular double plating methods.

MATERIALS AND METHODS

A total of 38 patients with distal humerus fractures, 20 in perpendicular plating group (group A) and 18 in parallel plating group (group B), were included in this prospective randomised study. At each follow up patients were evaluated clinically and radiologically for union and the outcomes were measured in terms of Mayo Elbow Performance Score (MEPS) consisting of pain intensity, range of motion, stability and function. MEP score greater than 90 is considered as excellent; Score 75 to 89 is good; Score 60 to 74 is fair and Score less than 60 is poor.

RESULTS

In our study, 15 patients (75%) in group A, and 13 patients (72.22%) in group B achieved excellent results. Two patients (10%) in group A and 4 patients (22.22%) in group B attained good results. Complications developed in 2 patients in each groups. No significant differences were found between the clinical outcomes of the two plating methods.

CONCLUSION

Neither of the plating techniques are superior to the other, as inferred from the insignificant differences in bony union, elbow function and complications between the two plating techniques.

Online Studies on Variation in Orthopedic Surgery: Computed Tomography in MPEG4 Versus DICOM Format

The purpose of this study was to compare the observer participation and satisfaction as well as interobserver reliability between two online platforms, Science of Variation Group (SOVG) and Traumaplatform Study Collaborative, for the evaluation of complex tibial plateau fractures using computed tomography in MPEG4 and DICOM format. A total of 143 observers started with the online evaluation of 15 complex tibial plateau fractures via either the SOVG or Traumaplatform Study Collaborative websites using MPEG4 videos or a DICOM viewer, respectively. Observers were asked to indicate the absence or presence of four tibial plateau fracture characteristics and to rate their satisfaction with the evaluation as provided by the respective online platforms. The observer participation rate was significantly higher in the SOVG (MPEG4 video) group compared to that in the Traumaplatform Study Collaborative (DICOM viewer) group (75 and 43%, respectively; P < 0.001). The median observer satisfaction with the online evaluation was seven (range, 0-10) using MPEG4 video compared to six (range, 1-9) using DICOM viewer (P = 0.11). The interobserver reliability for recognition of fracture characteristics in complex tibial plateau fractures was higher for the evaluation using MPEG4 video. In conclusion, observer participation and interobserver reliability for the characterization of tibial plateau fractures was greater with MPEG4 videos than with a standard DICOM viewer, while there was no difference in observer satisfaction. Future reliability studies should account for the method of delivering images.

Interpretation of Post-operative Distal Humerus Radiographs After Internal Fixation: Prediction of Later Loss of Fixation

PURPOSE

Stable fixation of distal humerus fracture fragments is necessary for adequate healing and maintenance of reduction. The purpose of this study was to measure the reliability and accuracy of interpretation of postoperative radiographs to predict which implants will loosen or break after operative treatment of bicolumnar distal humerus fractures. We also addressed agreement among surgeons regarding which fracture fixation will loosen or break and the influence of years in independent practice, location of practice, and so forth.

METHODS

A total of 232 orthopedic residents and surgeons from around the world evaluated 24 anteroposterior and lateral radiographs of distal humerus fractures on a Web-based platform to predict which implants would loosen or break. Agreement among observers was measured using the multi-rater kappa measure.

RESULTS

The sensitivity of prediction of failure of fixation of distal humerus fracture on radiographs was 63%, specificity was 53%, positive predictive value was 36%, the negative predictive value was 78%, and accuracy was 56%. There was fair interobserver agreement (κ = 0.27) regarding predictions of failure of fixation of distal humerus fracture on radiographs. Interobserver variability did not change when assessed for the various subgroups.

CONCLUSIONS

When experienced and skilled surgeons perform fixation of type C distal humerus fracture, the immediate postoperative radiograph is not predictive of fixation failure. Reoperation based on the probability of failure might not be advisable.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

Interobserver reliability of the Schatzker and Luo classification systems for tibial plateau fractures

INTRODUCTION

Tibial plateau fracture classification systems have limited interobserver reliability and new systems emerge. The purpose of this study was to compare the reliability of the Luo classification and the Schatzker classification for two-dimensional computed tomography (2DCT) and to study the effect of adding three-dimensional computed tomography (3DCT).

MATERIALS AND METHODS

Eighty-one observers, orthopedic surgeons and residents, were randomized to either 2DCT or 2D- and 3DCT evaluation of a spectrum of 15 complex tibial plateau fractures using web-based platforms in order to classify according to the Schatzker and according to Luo's Three Column classification. Reliability was calculated with the use of Siegel and Castellan's multirater kappa measure. Kappa values were interpreted according to the categorical rating by Landis and Koch.

RESULTS

Overall interobserver reliability of the Schatzker classification was significantly better compared to the Luo classification (kSchatzker=0.32 and kLuo=0.28, P=0.021), however, 'fair' for both fracture classification systems. For the Schatzker classification observers agreed significantly better on 2DCT compared to 2D- and 3DCT (k2DCT=0.37 and k2D+3DCT=0.29, P<0.001). The addition of 3DCT did not improve the overall interobserver reliability for the Luo classification as well, as kappa values were not significantly different on 2DCT and 2D- and 3DCT (k2DCT=0.31 and k2D+3DCT=0.25, P=0.096).

CONCLUSIONS

The agreement between observers was significantly better for the Schatzker classification compared to Luo's Three Column classification, however agreement was fair for both classification systems. Furthermore, the addition of 3DCT reconstructions did not improve the reliability of CT-based evaluation of tibial plateau fractures. Considering that new classification systems and 3DCT do not seem to improve agreement between surgeons, other efforts are needed that lead to more reliable diagnosis of complex tibial plateau fractures.

Three-Dimensional Computed Tomographic Analysis for Comminution of Pertrochanteric Femoral Fracture: Comminuted Anterior Cortex as a Predictor of Cutting Out

Background:

Fixed angle sliding hip screw devices allow controlled impaction between the head neck fragment and the femoral shaft fragment in the surgical treatment of pertrochanteric fractures. This study was performed to evaluate the frequency and pattern of comminution at the fracture site, which may prevent the intended impaction.

Materials and Methods:

Three-dimensional computed tomography was used to investigate 101 pertrochanteric fractures treated with fixed angle sliding hip screw devices, with emphasis on the comminuted cortex. A comminuted fracture was defined as a fracture that had a third fracture fragment at the main fracture line.

Results:

There were 40 fractures without comminution and 61 with comminution. All 61 comminuted fractures had a comminuted posterior cortex, and 3 of 61 fractures also had comminution at the anterior cortex. The prevalence of cutting out of the implant from the femoral head was significantly higher in cases involving comminution at both the posterior and anterior cortices than in cases involving comminution only at the posterior cortex (66.7 % and 3.4 %, p < 0.0001).

Conclusion:

The posterior cortex was comminuted in 60.4% of pertrochanteric fractures and the anterior cortex in 3.0%. Intended impaction at the fracture site could not be obtained at any cortex in cases with comminution at both the anterior and posterior cortices; comminution at the anterior cortex may be a predictor of cutting out.

6-week radiographs unsuitable for diagnosis of suspected scaphoid fractures

INTRODUCTION

Six week follow-up radiographs are a common reference standard for the diagnosis of suspected scaphoid fractures. The main purpose of this study was to evaluate the interobserver reliability and diagnostic performance characteristics of 6-weeks radiographs for the detection of scaphoid fractures. In addition, two online techniques for evaluating radiographs were compared.

MATERIALS AND METHODS

A total of 81 orthopedic surgeons affiliated with the Science of Variation Group assessed initial and 6-week scaphoid-specific radiographs of a consecutive series of 34 patients with suspected scaphoid fractures. They were randomized in two groups for evaluation, one used a standard website showing JPEG files and one a more sophisticated image viewer (DICOM). The goal was to identify the presence or absence of a (consolidated) scaphoid fracture. Interobserver reliability was calculated using the multirater kappa measure. Diagnostic performance characteristics were calculated according to standard formulas with CT and MRI upon presentation in the emergency department as reference standards.

RESULTS

The interobserver agreement of 6-week radiographs for the diagnosis of scaphoid fractures was slight for both JPEG and DICOM (k = 0.15 and k = 0.14, respectively). The sensitivity (range 42-79 %) and negative predictive value (range 79-94 %) were significantly higher using a DICOM viewer compared to JPEG images. There were no differences in specificity (range 53-59 %), accuracy (range 53-58 %), and positive predictive value (range 14-26 %) between the groups.

CONCLUSIONS

Due to low agreement between observers for the recognition of scaphoid fractures and poor diagnostic performance, 6-week radiographs are not adequate for evaluating suspected scaphoid fractures. The online evaluation of radiographs using a DICOM viewer seem to improve diagnostic performance characteristics compared to static JPEG images and future reliability and diagnostic studies should account for variation due to the method of delivering medical images.

LEVEL OF EVIDENCE

Diagnostic level II.

Capitellar and Trochlear Fractures

Fractures of the capitellum and trochlea account for a small proportion of elbow trauma. Clinicians need to be vigilant in their assessment as they are commonly associated with other injuries about the elbow. To optimize outcomes, the goals of management include a stable, anatomic reduction and early range of motion. Closed reduction of noncomminuted fractures may be successful but requires close follow-up. Open reduction and internal fixation is the preferred management of displaced capitellum-trochlear fractures. Elbow stiffness is the most commonly reported complication in operatively treated fractures. Arthroscopic-assisted reduction and internal fixation and arthroplasty are evolving management options.

The effect of three-dimensional computed tomography reconstructions on preoperative planning of tibial plateau fractures: a case-control series

BACKGROUND

Tibial plateau fractures are a common intra-articular injury for which computed tomography (CT) scans are routinely used for preoperative planning. Three-dimensional reconstructions of CT scans have been increasingly investigated in recent years, however their role has yet to be defined. We wish to investigate the role of three-dimensional computed tomography reconstructions (3D-CT) in the preoperative planning of tibial plateau fractures.

METHODS

Twelve cases of tibial plateau fractures including plain film radiographs and conventional CT scans were distributed to 21 observers (orthopaedic residents and consultants). The observers filled out a preoperative plan checklist created for this study. Three months later the same cases were distributed, in random order, this time including 3D-CT reconstructions. The same preoperative checklists were completed, and compared to the previous checklists.

RESULTS

The preoperative plan checklist was able to detect differences between cases and between observers. No significant differences were detected between the total plan scores when comparing conventional CT to 3D-CT. Sub-analysis of plan specifics (incisions, hardware, adjuncts) was also not significantly different. The level of training of the observer or the fracture complexity did not affect these results.

CONCLUSIONS

No significant changes were made to observer's preoperative plans with the addition of 3D-CT. 3D-CT reconstructions come at a cost to the system, and therefore their usefulness should be investigated prior to widespread use. Our study demonstrates that the addition of 3D-CT reconstructions to the preoperative workup of tibial plateau fractures did not change management plans when compared to plans made using traditional CT-scans.

Is the cortical thickness index a valid parameter to assess bone mineral density in geriatric patients with hip fractures?

INTRODUCTION

Reduced bone quality is a common problem during surgical fixation of geriatric hip fractures. The cortical thickness index (CTI) was proposed to assess the bone mineral density (BMD) of the proximal femur on the basis of plain X-rays. The purpose of this study was to evaluate the inter- and intraobserver reliability of the CTI and to investigate correlation between CTI and BMD in geriatric patients.

METHODS

60 patients (20 pertrochanteric fractures, 20 femoral neck fractures, 20 without fractures) were included. All patients had ap and lateral hip X-rays and measurement of BMD by Dual Energy X-ray Absorptiometry at different areas of the hip. The ap and lateral CTI was measured twice by four blinded observers and correlation between mean CTI and BMD was calculated.

RESULTS

Mean ap CTI was 0.52 and mean lateral CTI was 0.45. Inter- and intraobserver reliability was good for ap CTI (ICC 0.71; 0.79) and lateral CTI (ICC 0.65; 0.69). A significant correlation between CTI and overall BMD was found in patients without fractures (r = 0.74; r = 0.67). No significant correlation between CTI and overall BMD was found in patients with proximal femoral fractures.

CONCLUSION

The CTI has sufficient reliability for the use in daily practice. It showed significant correlation with BMD in patients without hip fractures. In patients with proximal femoral fractures, no correlation between CTI and BMD was found. We do not recommend the CTI as parameter to assess the BMD of the proximal femur in geriatric patients with hip fractures.

Comparative use of the computer-aided angiography and rapid prototyping technology versus conventional imaging in the management of the Tile C pelvic fractures

INTRODUCTION

Computed tomography (CT) scan with three-dimensional (3D) reconstruction has been used to evaluate complex fractures in pre-operative planning. In this study, rapid prototyping of a life-size model based on 3D reconstructions including bone and vessel was applied to evaluate the feasibility and prospect of these new technologies in surgical therapy of Tile C pelvic fractures by observing intra- and perioperative outcomes.

MATERIALS AND METHODS

The authors conducted a retrospective study on a group of 157 consecutive patients with Tile C pelvic fractures. Seventy-six patients were treated with conventional pre-operative preparation (A group) and 81 patients were treated with the help of computer-aided angiography and rapid prototyping technology (B group). Assessment of the two groups considered the following perioperative parameters: length of surgical procedure, intra-operative complications, intra- and postoperative blood loss, postoperative pain, postoperative nausea and vomiting (PONV), length of stay, and type of discharge.

RESULTS

The two groups were homogeneous when compared in relation to mean age, sex, body weight, injury severity score, associated injuries and pelvic fracture severity score. Group B was performed in less time (105 ± 19 minutes vs. 122 ± 23 minutes) and blood loss (31.0 ± 8.2 g/L vs. 36.2 ± 7.4 g/L) compared with group A. Patients in group B experienced less pain (2.5 ± 2.3 NRS score vs. 2.8 ± 2.0 NRS score), and PONV affected only 8 % versus 10 % of cases. Times to discharge were shorter (7.8 ± 2.0 days vs. 10.2 ± 3.1 days) in group B, and most of patients were discharged to home.

CONCLUSIONS

In our study, patients of Tile C pelvic fractures treated with computer-aided angiography and rapid prototyping technology had a better perioperative outcome than patients treated with conventional pre-operative preparation. Further studies are necessary to investigate the advantages in terms of clinical results in the short and long run.

The dorsal tangential X-ray view to determine dorsal screw penetration during volar plating of distal radius fractures

PURPOSE

To evaluate whether the dorsal tangential view (DTV) allows for reliable and valid in vivo measurement of the distance between screw tips and the dorsal radial cortex (STCD) during volar plating of distal radius fractures.

METHODS

Subjects included 22 patients with displaced distal radius fractures who had volar plate osteosynthesis. We performed standardized DTV images intraoperatively. After surgery, we performed computed tomography (CT) scans with reconstructions parallel to the distal screws. Three independent observers blinded to the study protocol measured the STCD on the basis of the DTV images and CT reconstructions. We calculated inter- and intraobserver reliability and the correlation between STCD values measured with DTV images and CT scans.

RESULTS

Eleven screws were changed intraoperatively. We observed no cases of postoperative screw perforations. Inter- and intraobserver reliability of STCD measurement was good when measured with DTV images and excellent when measured on the basis of CT reconstructions. Statistical analysis showed a good correlation between mean STCD values measured with DTV and CT.

CONCLUSIONS

The DTV allowed in vivo evaluation of the dorsal radial cortex and enabled reliable assessment of the distance between the screw tip and the dorsal cortex. It may allow detection of dorsal screw perforation during volar plating of distal radial fractures.

The effectiveness of skeletal imaging for quality assessment in posterior cruciate ligament reconstruction: reliability and validity of radiographs and computed tomography

PURPOSE

For intra- and postoperative evaluation of precise and anatomic graft tunnel position, radiographs (XR) and computed tomography (CT) scans have been suggested. The purpose of this study was to evaluate the reliability and validity of XR and CT for quality assessment following PCL reconstruction.

METHODS

Postoperative radiographs and CT scans were obtained in 45 consecutive patients following a standard single-bundle PCL reconstruction. Femoral and tibial tunnel apertures were correlated to femoral and tibial measurement grid systems. To assess the reliability and validity of XR and CT scans three independent observers evaluated radiographic and CT images for the position of femoral and tibial tunnel apertures.

RESULTS

Almost perfect inter- and intra observer agreement (0.79-0.99) was found for all CT measurements except for the distance of the tunnel position to the previous physis line. Almost perfect and strong inter- and intraobserver agreement (0.70-0.98) was found for all tibial measurements on XR which tended to increase with repeated interpretation and to decrease with low levels of observer qualification. Femoral measurements yielded only poor-to-moderate reliability (0.02-0.5) between raters on XR but strong intraagreement within experienced observers (0.45-0.86). Specificity for XR was calculated with 75.7 % for P2 and P3 and with 71 % for femoral tunnel depth and height.

CONCLUSION

XR and CT represent complementary imaging modalities and both offer considerable accuracy and precision for the determination of femoral and tibial tunnel apertures following PCL reconstruction and can be recommended for intra- and postoperative quality assessment.

Biomechanical studies: science (f)or common sense?

INTRODUCTION

It is our impression that many biomechanical studies invest substantial resources studying the obvious: that more and larger metal is stronger. The purpose of this study is to evaluate if a subset of biomechanical studies comparing fixation constructs just document common sense.

METHODS

Using a web-based survey, 274 orthopaedic surgeons and 81 medical students predicted the results of 11 biomechanical studies comparing fracture fixation constructs (selected based on the authors' sense that the answer was obvious prior to performing the study). Sensitivity, specificity, and accuracy were calculated according to standard formulas. The agreement among the observers was calculated by using a multirater kappa, described by Siegel and Castellan.

RESULTS

The accuracy of predicting outcomes was 80% or greater for 10 of 11 studies. Accuracy was not influenced by level of experience (i.e., time in practice and medical students vs. surgeons). There were substantial differences in accuracy between observers from different regions. The overall categorical rating of inter-observer reliability according to Landis and Koch was moderate (κ=0.55; standard error (SE)=0.01).

CONCLUSION

The results of a subset of biomechanical studies comparing fracture fixation constructs can be predicted prior to doing the study. As these studies are time and resource intensive, one criterion for proceeding with a biomechanical study should be that the answer is not simply a matter of common sense.

Reproducibility of classifications for olecranon fractures

INTRODUCTION

Fractures of the olecranon are relatively common injuries in adults and are of great clinical importance. Classification systems have been developed as tools to assist surgeons in grouping different types of fractures, to facilitate communication and to standardise treatment, but none of the systems used today is universally accepted for olecranon fractures.

METHODS

Fifty-nine olecranon fractures were classified according to the Schatzker, Colton, Mayo and AO/ASIF systems by four observers with different levels of expertise. Intra- and inter-observer agreement was assessed. Each observer analysed the images at three different times; the images were randomised and presented in a different sequence at each assessment.

RESULTS

There was higher mean intra-observer agreement in the AO/ASIF (0.60) and Mayo (0.64) classifications compared with the Schatzker (0.49) and Colton (0.38) classifications. Inter-observer agreement was better with AO/ASIF and Mayo (0.35 and 0.32, respectively) than with Schatzker and Colton (0.29 and 0.12, respectively).

CONCLUSION

The results of this study indicate that the most commonly used classifications for olecranon fractures are associated with low reproducibility.

Three-dimensional computed tomography is not indicated for the classification and characterization of calcaneal fractures

This study determined inter- and intra-observer reliability for measurement of the angles of Böhler and Gissane, for the decision between surgical or conservative management and for the three mostly used classification systems for calcaneal fractures with the use of 2D-CT imaging versus 2D- and 3D-CT imaging. A consecutive series of 38 fractures in 36 patients, treated at a level II trauma centre between 2005 and 2008, were evaluated in two rounds by five observers. We measured the inter- and intraobserver reliability for the Sanders', Zwipp and Essex-Lopresti classification systems using the kappa values as described by Cohen. The intraclass correlation coefficient as described by Shrout and Fleiss was used to analyze inter- and intra-observer reliability of the angles of Böhler and Gissane. Usage of 2D-CT imaging interobserver reliability was fair for the Sanders' and Zwipp classifications and for measurement of the angle of Gissane, and it was moderate for measurement of the Essex-Lopresti classification system and measurement of the angle of Böhler. With the addition of 3D-CT imaging, the interobserver reliability was fair for the Sanders', Zwipp and Essex-Lopresti classification systems. The intraobserver reliability was fair for measurement of the angle of Gissane and it was moderate for the Sanders', Zwipp and Essex-Lopresti classification systems and for the measurement of the angle of Böhler. The addition of three-dimensional CT imaging did not increase inter- and intraobserver reliability for the classification of calcaneal fractures. Authors commented they experienced no additional benefit from 3D-CT imaging for the assessment of calcaneal fractures.

Distal humerus shear-fractures: "Built-on" surgical technique

When treating a distal humeral shear fracture, comminution of the lateral column may preclude the reconstruction of the lateral articular fragments.

In this article a new strategy for the management lateral column comminuted shear-fractures (LCCSF) is presented, called the “built-on” surgical technique. Three goals are obtained by this technique: (1) Restoration of the lateral column bone stock; (2) Provision of a solid scaffold for the repair of the lateral ulnar collateral ligament (LUCL); and (3) Provision of a sable platform for the reconstruction and fixation of the articular fragments.

We will obtain these goals through the following surgical steps:

1/ Reconstruction of the lateral trochlea.

2/ Reconstruction of the lateral column

3/ Fixation of the Capitellum

4/ Reconstruction of the LUCL

Usefulness and reliability of two- and three-dimensional computed tomography in patients older than 65 years with distal humerus fractures

BACKGROUND

Distal humerus fractures are difficult to characterise and to classify according to the AO system. In this multicentre study, our objectives were to assess the usefulness of computed tomography (CT) and to measure intra-observer and inter-observer reliability according to observer experience.

MATERIALS AND METHODS

An online survey of professional practice was performed using a questionnaire based on a clinical case. Participants were asked to determine the AO classification using radiographs then to reappraise their answers after the addition of CT images. For the reliability study, 16 observers in five centres evaluated radiographs and CT scans of 26 distal humerus fractures. They used the radiographs to determine the AO classification and assess the main fracture characteristics then reappraised their findings after adding the CT images. The radiographs and 2D CT images were read twice at an interval of 2 weeks, and during the second reading, 3D CT images were available also. At least 1 month later, the same observers performed similar readings 2 weeks apart (radiographs and 2D CT images at the first reading and addition of 3D CT images at the second reading).

RESULTS

Correct fracture classification was achieved in 95% of cases with the CT images compared to only 73% with the radiographs. CT led to diagnostic and therapeutic changes in 90% and 25% of cases, respectively. Inter-observer reliability was poor for both AO classification and fracture characteristics, not only with the radiographs and 2D CT images, but also with the added 3D CT images. In contrast, intra-observer reliability improved after the addition of 3D CT images. Assessment accuracy was influenced by image quality and geographic origin of the observer but not by observer experience.

CONCLUSION

CT improves diagnostic accuracy and, in some cases, changes the surgical strategy. In our study of a large number of observers, CT did not improve inter-observer agreement about the study variables. Intra-observer agreement was improved by 3D CT but not by 2D CT. Accuracy was not influenced by years of observer experience but was dependent on image quality, proficiency with computer-based tools and, above all, image observation and interpretation.

LEVEL OF EVIDENCE

Level III.

Articular fractures of the distal humerus

Distal humeral fractures represent 2% of all adult elbow fractures. Injury mechanisms include high-energy trauma with skin involvement, and low energy trauma in osteoporotic bone. Treatment goals are anatomical restoration in young, high-demand patients and quick recovery of activities of daily living in the elderly. Complete fractures are relatively easy to diagnose, but partial intra-articular fractures are not. The clinical diagnosis must take into account potential complications such as open injuries and ulnar nerve trauma. Standard X-rays with additional distraction series in the operating room are sufficient in complete articular fracture cases. Partial intra-articular fractures will need CT scan and 3D reconstruction to fully evaluate the involved fragments. SOFCOT, AO/OTA and Dubberley classifications are the most useful for describing fractures and selecting treatment. Surgery is the optimal treatment and planning is based on fracture type. Complete fractures are treated using a posterior approach. Triceps management is a function of fracture lines and type of fixation planned. Constructs using two plates at 90° or 180° are the most stable, with additional frontal screw for intercondylar fractures. Elbow arthroplasty may be indicated in selected patients, having severely communited distal humerus fractures and osteoporotic bone. Open fractures make fixation and wound management more challenging and unfortunately have poorer outcomes. Other complications are elbow stiffness, non-union, malunion and heterotopic ossification.

Diagnostic accuracy of two-dimensional and three-dimensional imaging and modeling of radial head fractures

To tests the hypothesis that classification and characterization of fractures of the radial head is more accurate with 3D than 2D computed tomography images and radiographs, using a prospective study design with intraoperative inspection as the reference standard. Treating surgeons and first assistants completed a questionnaire assigning a fracture type according to the Broberg and Morrey modification of Mason's classification, evaluating selected fracture characteristics, and electing preferred management based upon radiographs and 2D images alone; then adding 3D-CT; then 3D printed physical models; and finally intra-operative visualization. The addition of the 3D CT and physical models improved the sensitivity for fracture line separating the entire head from the neck, comminution of the radial neck, fracture involving the articular surface, articular fracture gap greater than 2 mm, impacted fracture fragments, greater than 3 articular fragments, and articular fragments judged too small to repair. There were no significant differences in diagnostic performance with the addition of 3D models. The addition of 3D CT and models improved the reliability of Broberg and Morrey classification. We conclude that 3DCT and 3D physical modeling provide more accurate fracture classification and characterization of fracture of the radial head with less proposed variability in treatment. We did not demonstrate a clear advantage for modeling over 3DCT reconstructions.

LEVEL OF EVIDENCE

Diagnostic, Level I.

The Roles of Mechanical Stresses in the Pathogenesis of Osteoarthritis: Implications for Treatment of Joint Injuries

Excessive joint surface loadings, either single (acute impact event) or repetitive (cumulative contact stress), can cause the clinical syndrome of osteoarthritis (OA). Despite advances in treatment of injured joints, the risk of OA following joint injuries has not decreased in the last 50 years. Cumulative excessive articular surface contact stress that leads to OA results from post-traumatic joint incongruity and instability, and joint dysplasia, but also may cause OA in patients without known joint abnormalities. In vitro investigations show that excessive articular cartilage loading triggers release of reactive oxygen species (ROS) from mitochondria, and that these ROS cause chondrocyte death and matrix degradation. Preventing release of ROS or inhibiting their effects preserves chondrocytes and their matrix. Fibronectin fragments released from articular cartilage subjected to excessive loads also stimulate matrix degradation; inhibition of molecular pathways initiated by these fragments prevents this effect. Additionally, injured chondrocytes release alarmins that activate chondroprogentior cells in vitro that propogate and migrate to regions of damaged cartilage. These cells also release chemokines and cytokines that may contribute to inflammation that causes progressive cartilage loss. Distraction and motion of osteoarthritic human ankles can promote joint remodeling, decrease pain and improve joint function in patients with end-stage post-traumatic OA. These advances in understanding of how altering mechanical stresses can lead to remodeling of osteoarthritic joints and how excessive stress causes loss of articular cartilage, including identification of mechanically induced mediators of cartilage loss, provide the basis for new biologic and mechanical approaches to the prevention and treatment of OA.

Diagnostic accuracy of 2- and 3-dimensional computed tomography and solid modeling of coronoid fractures

PURPOSE

This study measured the diagnostic performance characteristics and reliability of 2-dimensional (2DCT) and 3-dimensional (3DCT) computed tomography images and modeling of coronoid fractures.

METHOD

The treating surgeon and first assistant evaluated 28 fractures for fracture type, specific characteristics, and proposed treatment. The observers evaluated the fractures 4 times: first based upon 2DCT computed images and radiographs; second with the addition of 3DCT images; third with the addition of 3D models; and finally based upon intra-operative exposure, which was considered the reference standard.

RESULTS

The diagnostic performance characteristics did not improve with more sophisticate imaging and models. The addition of 3DCT reconstructions improved the inter-observer reliability for fracture classification, characteristics, and proposed treatment.

CONCLUSION

More sophisticated images and modeling improved reliability but not accuracy when characterizing coronoid fractures.

Midterm Results of 58 Fractures of the Coronoid Process of the Ulna and their Concomitant Injuries

BACKGROUND

In general, fractures of the coronoid process are rare and usually occur in combination with additional elbow joint injuries. The treatment of these injuries aims to regain a stable as well as a flexible and loadable joint. Although there is currently little evidence, therapy recommendations remain controversial. Therefore, the aim of this study was to prognostically determine relevant factors for therapy recommendation by analysing a representative patient population of two trans-regional trauma centres.

MATERIAL AND METHODS

Seventy-seven patients with a fracture of the coronoid process were treated within an 8-year period (2001 to 2009). After an average of 48 months (SD 31), treatment outcome of 58 patients (75%) was acquired. The results were statistically analysed.

RESULTS

The average age of the patient was 51.8 years (SD 13.6); 36 were male and 34 had a fracture on the right arm. Applying the fracture types of the coronoid process in accordance with Regan/Morrey, the result was: Type I (19), II (17) and III (22). Further injuries were also detected: 40 radial head fractures, 17 proximal ulnar fractures and 2 fractures of the olecranon. A luxation was detected in 44 of the 58 patients (76%). The patients' average MEPS (Mayo Elbow Performance Score) was 80.6 points (SD 18), with significant differences between the various therapy strategies. Fifteen% of the coronoid process fractures were reconstructable to a limited extent only by means of osteosynthesis. In 33% of the patients, instabilities remained. The average extension/flexion came to 107° (SD 28), and pronation and supination 153° (SD 38).

CONCLUSION

At present, a surgical therapy of ligamentary injuries cannot be statistically justified. A stable osseous reconstruction appears to make more sense. The strongest negative prognostic parameters in our patient population were: therapy with an external fixator, immobilisation for more than 21 days, the occurrence of complications and unstable osteosyntheses on the coronoid process.

CT scan does not improve the reproducibility of trochanteric fracture classification: a prospective observational study of 53 cases

INTRODUCTION

The reproducibility of various classification systems for trochanteric fractures is poor. This problem could be related to a lack of readability when using conventional X-rays.

HYPOTHESIS

Computed tomography scanning (CT scan) will improve the interobserver reproducibility of the AO classification for trochanteric fractures.

PATIENTS AND METHODS

This was a prospective, observational, descriptive study following a group of 53 patients with trochanteric fractures. The fractures were evaluated with conventional X-rays, CT scan slices and 3D reconstruction (3DR). The resulting images were blinded and analysed by two observers using two classification systems: AO and Evans modified by Jensen (EVJE). A sample size of 53 was needed to show an improvement in the interobserver reproducibility when deciding the AO classification type with CT scan images. Kappa coefficients were used to measure interobserver reproducibility and agreement; agreement is the degree of consistency in the analysis by one observer who views the same fracture on two different imaging modalities.

RESULTS

The interobserver reproducibility for the AO classification was 0.28 for X-rays, 0.33 for CT scan and 0.28 for 3DR. For the EVJE classification, these coefficients were 0.50 for X-rays, 0.35 for CT scan and 0.47 for 3DR. The agreement rate between the two imaging modalities was between 0.38 and 0.58 for X-rays/CT scan and between 0.79 and 0.86 for CT scan/3DR.

DISCUSSION

The primary objective of this study was not achieved. CT imaging does not improve the interobserver reproducibility of various classification systems for trochanteric fractures. However, by providing images as slices, the complex nature of fractures in this area was revealed. The challenges related to classifying various fractures are not exclusively related to a "readability" problem, but also an understanding and analysis problem.

LEVEL OF EVIDENCE

Prospective diagnostic study, level III.

Distal humerus fractures in the elderly: osteosynthesis or endoprosthesis? Review of the literature

Fractures of the distal humerus in adults are rare but challenging for the orthopaedic trauma surgeon. The bimodal distribution reflects the trauma mechanism. While distal humerus fractures are caused by high-energy traumata in young male adults, a fall from a standing height is the most common reason for humerus fractures among elderly females. As a rule, fractures of the distal humerus are treated surgically. In young patients, open reduction and internal fixation (ORIF) with anatomic locking plates are the gold standard. In elderly patients, reconstruction is not always possible, and total elbow arthroplasty (TEA) becomes necessary. The present article provides an overview of the current diagnostic and treatment recommendations. The current literature is reviewed and the results discussed.

Coronal shear fractures of the distal humerus

Management of coronal shear fractures of the distal humerus has evolved considerably over the past 3 decades, with an increased appreciation of the complexity of these fractures, improvements in internal fixation techniques, and the use of more extensile exposures. Nearly all of these fractures are displaced, given the paucity of soft tissue attachments and correspondingly, nonsurgical management is fraught with complications including chronic pain, mechanical symptoms, and instability and is not recommended. Good to excellent outcomes can be achieved in the majority of patients with open reduction internal fixation, particularly when the fracture is limited to the radiocapitellar joint. Outcomes are worst for those with considerable medial extension or comminution. Computed tomography is highly recommended to guide surgical planning. The presence of posterior comminution or extension to the medial column might require more extensile exposures and supplemental fixation for adequate stability. Arthroscopic reduction and fixation techniques have been described for the simple fracture. Those not amenable to fixation might do better with total elbow arthroplasty in a select population. Long-term data demonstrate the durability of these elbows following open reduction internal fixation. Complications other than stiffness are rare. Radiographic avascular necrosis does not appear to affect outcome. Radiographic mild to moderate arthritis was observed in half of patients at 17-year follow-up.

Reducing interrater variability and improving health care: a meta-analytical review

OBJECTIVES

In the scientific literature about reliability, the main approach to increasing reliability seems to involve increasing the number of observers and improving the instrument used. Other aspects for improving reliability - like the training of raters - seem to receive less notice. It is worth asking whether this technical approach could be complemented by training the user of the instrument. A systematic meta-analytical review of the research literature was performed to answer this question and examine the effectiveness of planned interventions for improving interrater reliability of health care professionals.

METHOD

The databases of PubMed (MEDLINE), Embase, Omega and PsycINFO were searched. The inclusion criteria were met by 57 studies. Details extracted from the studies included the study design, the number of observers and the number of observed cases, the intervention, the type of instrument (whether or not it was highly technical), and statistical information about the agreement before and after the intervention. Interventions were categorized into three groups: training of professionals, improving the diagnostic instrument and a combination of training and improving the instrument. A meta-analysis was performed by means of linear regression.

RESULTS

The interventions were arranged according to their effectiveness in improving the diagnostic instrument (mean change: β = 0.13), training combined with improving the instrument (mean change: β = 0.10) and training (mean change: β = 0.09).

CONCLUSION

On average, although all types of interventions are effective, improving the diagnostic instrument seems to be the most effective. Especially when highly technical instruments were concerned, improvement proved to be very effective (β = 0.52). Because instrumental variables constitute a major source of error, improving the instrument is an important approach. However, this review offers solid arguments that can complement the literature and practice, with a focus on training the user of the instrument.

Total talar fracture - inter- and intra-observer reproducibility of two classification systems (Hawkins and AO) for central talar fractures

INTRODUCTION

We evaluated the inter- and intra-observer reproducibility of two classification systems for central talar fractures (Hawkins, as modified by Canal and Kelly and then by us; AO/AOT).

HYPOTHESIS

The analysis and classification of these fractures will be better with CT scans than with X-rays.

MATERIAL AND METHODS

Four observers evaluated 39 X-ray and CT scan files twice in the span of six weeks; each evaluation entailed classifying the fractures and describing their main features. Cohen's Kappa coefficient for inter-rater agreement was calculated and analysed.

RESULTS

The inter- and intra-observer reproducibility with CT scans was better with X-rays for most of the parameters evaluated. The modified Hawkins classification provided better reproducibility than the AO/AOT one. However, this classification system was not perfect, even after modifications and use of CT scans.

DISCUSSION

CT scans are an essential tool for the analysis of all talar fractures. We modified the Hawkins classification (as modified by Canal and Kelly) to include a Type 0 (no displacement or less than 2mm), include frontal body fractures that are displaced like neck fractures and take into account comminuted fractures and other trauma in the area.

LEVEL OF PROOF

IV - retrospective clinical study.

Diagnostic accuracy of 2- and 3-dimensional imaging and modeling of distal humerus fractures

PURPOSE

This investigation used prospectively recorded intraoperative evaluation as the reference standard for distal humerus fracture type and characteristics, in order to measure the diagnostic performance characteristics of computed tomography (CT) and physical models. In secondary analyses, we assessed the reliability of classification.

METHODS

Thirty-five fractures were evaluated by the treating surgeon and first assistant on radiographs and 2-dimensional CT (2DCT) images first; a second time based on radiographs and 2- and 3-dimensional CT (3DCT) images; a third time based on 2- and 3DCT as well as 3D physical models; and a fourth time based on intraoperative visualization of the fracture characteristics. The intraoperative evaluation of the attending surgeon was used as the reference standard.

RESULTS

The addition of 3DCT and the 3D models to 2DCT and radiographs led to significant improvements in sensitivity, but not specificity, in the diagnosis and proposed treatment, and improved the interobserver agreement with respect to specific fracture characteristics but not classification.

CONCLUSION

Increasingly sophisticated imaging and modeling leads to slight but significant improvements in diagnostic performance characteristics and interobserver agreement on fracture characteristics.

Two-dimensional and three-dimensional computed tomography for the classification and characterisation of tibial plateau fractures

BACKGROUND

Complex tibial plateau fractures can be difficult to characterise on plain radiographs and two-dimensional computed tomography (2D CT). The present study evaluated whether three-dimensional computed tomography (3D CT) reconstructions can improve the reliability of complex tibial plateau fracture characterisation and classification.

METHODS

Forty-five consecutive intra-articular fractures of the tibial plateau were evaluated by six independent observers for classification according to standard systems and for the presence of six characteristics: (1) posteromedial shear fracture; (2) coronal plane fracture; (3) lateral condylar impaction; (4) medial condylar impaction; (5) tibial spine involvement; and (6) separation of tibial tubercle necessitating fixation. Two rounds of characterisation and classification were performed: the first classification after a combination of plain radiographs and 2D CT and the second one after 3D CT information were added.

RESULTS

3D CT improved the average 'inter'-observer reliability of the Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) classification (κ2D=0.536, 95% confidence interval (CI): 0.481-0.591 vs. κ3D=0.545, 95% CI: 0.478-0.612), the Hohl and Moore classification (κ2D=0.668, 95% CI: 0.605-0.732 vs. κ3D=0.746, 95% CI: 0.605-0.732) and of the Schatzker classification (κ2D=0.545, 95% CI: 0.494-0.596 vs. κ3D=0.596, 95% CI: 0.538-0.654). 'Intra'-observer reliability also improved non-significantly for all systems after the addition of 3D CT for individual observers. 3D CT did improve the 'intra'-observer reliability for the identification of the following fracture characteristics: coronal plane fracture (average κ2D=0.700, interquartile range (IQR): 0.551-0.820 vs. average κ3D=0.774, IQR: 0.692-0.847); lateral condylar impaction (average, κ2D=IQR: 0.675-0.901 to 1.000 vs. average, κ3D=0.785, IQR 0.737-0.807); medial condylar impaction (average κ2D=0.631, IQR: 0.537-0.670 vs. κ3D=0.719, IQR: 0.679-0.895); tibial spine involvement average (κ2D=0.621, IQR 0.545-0.678 vs. average κ3D=0.705, IQR: 0.652-0.794); separation of tibial tubercle necessitating fixation (average κ2D=0.332, IQR: 0.080-0.574 vs. average κ3D=0.441, IQR: 0.325-0.681). The only improvement that was found to be statistically significant was for recognition of medial condylar impaction as the IQR did not overlap. 3D CT had limited influence on average 'inter'-observer reliability for the recognition of all specific fracture characteristics (κ2D=0.488 vs. κ3D=0.485, both moderate agreement for all fracture characteristics) but showed a non-significant improvement of the recognition of coronal plane fractures (fair to moderate; κ2D=0.398, 95% CI: 0.273-0.523 to κ3D=0.418, 95% CI: 0.262-0.574) and recognition of impaction of the lateral condyle (κ2D=0.614, 95% CI: 0.467-0.760 to κ3D=0.693, 95% CI: 0.538-0.849).

CONCLUSIONS

The added value of 3D CT after 2D CT is limited and does not significantly improve reliability of characterisation and classification of tibial plateau fractures.

Interobserver reliability of radial head fracture classification: two-dimensional compared with three-dimensional CT

BACKGROUND

The Broberg and Morrey modification of the Mason classification of radial head fractures has substantial interobserver variation. This study used a large web-based collaborative of experienced orthopaedic surgeons to test the hypothesis that three-dimensional reconstructions of computed tomography (CT) scans improve the interobserver reliability of the classification of radial head fractures according to the Broberg and Morrey modification of the Mason classification.

METHODS

Eighty-five orthopaedic surgeons evaluated twelve radial head fractures. They were randomly assigned to review either radiographs and two-dimensional CT scans or radiographs and three-dimensional CT images to determine the fracture classification, fracture characteristics, and treatment recommendations. The kappa multirater measure (κ) was calculated to estimate agreement between observers.

RESULTS

Three-dimensional CT had moderate agreement and two-dimensional CT had fair agreement among observers for the Broberg and Morrey modification of the Mason classification, a difference that was significant. Observers assessed seven fracture characteristics, including fracture line, comminution, articular surface involvement, articular step or gap of ≥2 mm, central impaction, recognition of more than three fracture fragments, and fracture fragments too small to repair. There was a significant difference in kappa values between three-dimensional CT and two-dimensional CT for fracture fragments too small to repair, recognition of three fracture fragments, and central impaction. The difference between the other four fracture characteristics was not significant. Among treatment recommendations, there was fair agreement for both three-dimensional CT and two-dimensional CT.

CONCLUSIONS

Although three-dimensional CT led to some small but significant decreases in interobserver variation, there is still considerable disagreement regarding classification and characterization of radial head fractures. Three-dimensional CT may be insufficient to optimize interobserver agreement.

Computer-assisted virtual surgical procedure for acetabular fractures based on real CT data

OBJECTIVE

To develop and evaluate a computer-assisted virtual surgical procedure for preoperative planning that simulates the reduction and plate fixation for acetabular fractures based on real computed tomography (CT) data using computer softwares on personal computers.

METHODS

Virtual preoperative planning for reduction and plate fixation for seven acetabular fractures was performed. Three-dimensional (3D) models of acetabular fractures based on real CT data in Dicom format were built to perform reduction first. Then fixation was undertaken after plate contouring. Virtual planning was compared with real surgery with respect to operative approach, plate length and screw count. Furthermore, the time required for virtual surgery was recorded.

RESULTS

Virtual surgery was successfully achieved and identical to the real operation in all cases. The mean time required was 79 min.

CONCLUSION

The virtual surgical procedure for acetabular fractures is feasible and useful clinically for surgeons to determine surgical planning. It may be a valuable tool for surgeons in learning about the nature of the fracture and in formulating an appropriate surgical plan.

Quantitative 3-dimensional computed tomography measurement of volar shearing fractures of the distal radius

PURPOSE

We used a method for quantitative measurement of articular surface area based on 3-dimensional computed tomography (CT) images to test the hypothesis that among volar shearing fractures of the distal radius, complete articular fractures have on average larger volar fracture fragments than partial articular fractures.

METHODS

We analyzed 25 adult patients with a quantitative 3-dimensional CT scan of a volar shearing fracture of the distal radius. We identified 3 major fracture patterns: 10 fractures were complete articular fractures (AO C-type; complete dorsal fracture line); 8 fractures had an intact dorsal lunate facet (radial dorsal fracture line; labeled transitional type B fractures); and 7 fractures had no dorsal fracture (true AO type B partial articular fractures).

RESULTS

All of the type C and transitional type B fractures, but only one of the true type B fractures had a split (fragmentation) in the dorsal articular surface (p < .001). Four of 10 type C, 6 of 8 partial type B and 2 of 7 type B fractures had fragmentation of the volar articular surface (p = .19). The articular surface area of the volar fragments in type B fractures tended to be larger (average 56%; range, 38% to 78% of the total articular surface area) compared with partial type B (average 42; range, 28% to 51%) and type C (47%; range, 25% to 68%) fractures although the differences were not statistically significant with the numbers available.

CONCLUSIONS

We identified 3 major volar shearing fracture patterns (complete, transitional partial, and partial articular). Although the differences in the average volar fractures surface area were not statistically significant with the numbers available, complete fractures and transitional partial fractures (intact dorsal lunate facet) were significantly more likely to have dorsal comminution.