Computed tomography of suspected scaphoid fractures

Understanding Pediatric Clinical Scaphoid Injuries: A Prospective Radiological Study

Background: Controversy exists in the management of children presenting with clinical suspicion of a scaphoid fracture but normal radiographs. The purpose of this study was to prospectively evaluate the potential role for advanced imaging in children with suspected scaphoid fractures. Methods: Participants with clinical suspicion of a scaphoid fracture but 2 sets of radiographs negative for fracture were casted and underwent both computed tomography (CT) and magnetic resonance imaging (MRI). The primary outcome was the prevalence of scaphoid fracture and other imaging findings. Results: Twenty-five participants were enrolled. Nine participants (36%) were found to have a scaphoid fracture on either CT or MRI. Concordance of CT and MRI was found in 64% of cases. Conclusion: Future studies are required to better understand the clinical significance of these injuries, the role of advanced imaging, and the most appropriate treatment in children with suspected scaphoid fractures.

Update on Management of Scaphoid Fractures

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Accurately diagnose scaphoid fractures through examination and appropriate imaging selection. 2. Recognize those fractures that can be treated with nonoperative management. 3. Outline the different surgical approaches for scaphoid fractures. 4. Appreciate the surgical options for management of scaphoid nonunion.

SUMMARY

This article includes the most up-to-date information on the diagnosis, work-up, and treatment of scaphoid fractures.

Deep Convolutional Neural Networks Provide Motion Grading for High-Resolution Peripheral Quantitative Computed Tomography of the Scaphoid

In vivo high-resolution peripheral quantitative computed tomography (HR-pQCT) studies on bone characteristics are limited, partly due to the lack of standardized and objective techniques to describe motion artifacts responsible for lower-quality images. This study investigates the ability of such deep-learning techniques to assess image quality in HR-pQCT datasets of human scaphoids. In total, 1451 stacks of 482 scaphoid images from 53 patients, each with up to six follow-ups within one year, and each with one non-displaced fractured and one contralateral intact scaphoid, were independently graded by three observers using a visual grading scale for motion artifacts. A 3D-CNN was used to assess image quality. The accuracy of the 3D-CNN to assess the image quality compared to the mean results of three skilled operators was between 92% and 96%. The 3D-CNN classifier reached an ROC-AUC score of 0.94. The average assessment time for one scaphoid was 2.5 s. This study demonstrates that a deep-learning approach for rating radiological image quality provides objective assessments of motion grading for the scaphoid with a high accuracy and a short assessment time. In the future, such a 3D-CNN approach can be used as a resource-saving and cost-effective tool to classify the image quality of HR-pQCT datasets in a reliable, reproducible and objective way.

Which clinical features best predict occult scaphoid fractures? A systematic review of diagnostic test accuracy studies

BACKGROUND

Plain radiographs cannot identify all scaphoid fractures; thus ED patients with a clinical suspicion of scaphoid injury often undergo immobilisation despite normal imaging. This study determined (1) the prevalence of scaphoid fracture among patients with a clinical suspicion of scaphoid injury with normal radiographs and (2) whether clinical features can identify patients that do not require immobilisation and further imaging.

METHODS

This systematic review of diagnostic test accuracy studies included all study designs that evaluated predictors of scaphoid fracture among patients with normal initial radiographs. Quality assessment was undertaken using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Meta-analyses included all studies.

RESULTS

Eight studies reported data on 1685 wrist injuries. The prevalence of scaphoid fracture despite normal radiographs was 9.0%. Most studies were at overall low risk of bias but two were at unclear risk; all eight were at low risk for applicability concerns. The most accurate clinical predictors of occult scaphoid fracture were pain when the examiner moved the wrist from a pronated to a supinated position against resistance (sensitivity 100%, specificity 97.9%, LR+ 45.0, 95% CI 6.5 to 312.5), supination strength <10% of contralateral side (sensitivity 84.6%, specificity 76.9%, LR+ 3.7, 95% CI 2.2 to 6.1), pain on ulnar deviation (sensitivity 55.2%, specificity 76.4%, LR+ 2.3, 95% CI 1.8 to 3.0) and pronation strength <10% of contralateral side (sensitivity 69.2%, specificity 64.6%, LR+ 2.0, 95% CI 1.2 to 3.2). Absence of anatomical snuffbox tenderness significantly reduced the likelihood of an occult scaphoid fracture (sensitivity 92.1%, specificity 48.4%, LR- 0.2, 95% CI 0.0 to 0.7).

CONCLUSION

No single feature satisfactorily excludes an occult scaphoid fracture. Further work should explore whether a combination of clinical features, possibly in conjunction with injury characteristics (such as mechanism) and a normal initial radiograph might exclude fracture. Pain on supination against resistance would benefit from external validation.

TRIAL REGISTRATION NUMBER

CRD42021290224.

What Is the Diagnostic Performance of Conventional Radiographs and Clinical Reassessment Compared With HR-pQCT Scaphoid Fracture Diagnosis?

BACKGROUND

Conventional radiographs and clinical reassessment are considered guides in managing clinically suspected scaphoid fractures. This is a unique study as it assessed the value of conventional radiographs and clinical reassessment in a cohort of patients, all of whom underwent additional imaging, regardless of the outcome of conventional radiographs and clinical reassessment.

QUESTIONS/PURPOSES

(1) What is the diagnostic performance of conventional radiographs in patients with a clinically suspected scaphoid fracture compared with high-resolution peripheral quantitative CT (HR-pQCT)? (2) What is the diagnostic performance of clinical reassessment in patients with a clinically suspected scaphoid fracture compared with HR-pQCT? (3) What is the diagnostic performance of conventional radiographs and clinical reassessment combined compared with HR-pQCT?

METHODS

Between December 2017 and October 2018, 162 patients with a clinically suspected scaphoid fracture presented to the emergency department (ED). Forty-six patients were excluded and another 25 were not willing or able to participate, which resulted in 91 included patients. All patients underwent conventional radiography in the ED and clinical reassessment 7 to 14 days later, together with CT and HR-pQCT. The diagnostic performance characteristics and accuracy of conventional radiographs and clinical reassessment were compared with those of HR-pQCT for the diagnosis of fractures since this was proven to be superior to CT scaphoid fracture detection. The cohort included 45 men and 46 women with a median (IQR) age of 52 years (29 to 67). Twenty-four patients with a median age of 44 years (35 to 65) were diagnosed with a scaphoid fracture on HR-pQCT.

RESULTS

When compared with HR-pQCT, conventional radiographs alone had a sensitivity of 67% (95% CI 45% to 84%), specificity of 85% (95% CI 74% to 93%), positive predictive value (PPV) of 62% (95% CI 46% to 75%), negative predictive value (NPV) of 88% (95% CI 80% to 93%), and a positive and negative likelihood ratio (LR) of 4.5 (95% CI 2.4 to 8.5) and 0.4 (95% CI 0.2 to 0.7), respectively. Compared with HR-pQCT, clinical reassessment alone resulted in a sensitivity of 58% (95% CI 37% to 78%), specificity of 42% (95% CI 30% to 54%), PPV of 26% (95% CI 19% to 35%), NPV of 74% (95% CI 62% to 83%), as well as a positive and negative LR of 1.0 (95% CI 0.7 to 1.5) and 1.0 (95% CI 0.6 to 1.7), respectively. Combining clinical examination with conventional radiography produced a sensitivity of 50% (95% CI 29% to 71%), specificity of 91% (95% CI 82% to 97%), PPV of 67% (95% CI 46% to 83%), NPV of 84% (95% CI 77% to 88%), as well as a positive and negative LR of 5.6 (95% CI 2.4 to 13.2) and 0.6 (95% CI 0.4 to 0.8), respectively.

CONCLUSION

The accuracy of conventional radiographs (80% compared with HR-pQCT) and clinical reassessment (46% compared with HR-pQCT) indicate that the value of clinical reassessment is limited in diagnosing scaphoid fractures and cannot be considered directive in managing scaphoid fractures. The combination of conventional radiographs and clinical reassessment does not increase the accuracy of these diagnostic tests compared with the accuracy of conventional radiographs alone and is therefore also limited in diagnosing scaphoid fractures.

LEVEL OF EVIDENCE

Level II, diagnostic study.

The current management of scaphoid fractures in the emergency department across an Australian metropolitan public health service: A retrospective cohort study

BACKGROUND

Scaphoid fractures are commonly present to emergency departments (EDs), challenging medical practitioners to achieve accurate diagnosis and management. This is because of the prevalence of radiographically occult scaphoid fractures and complications associated with missed diagnoses. Clinical Guidelines are limited for treatment of suspected scaphoid fractures, and heterogeneity in the literature further complicates management. This study aimed to explore the differences in management between practitioners in the ED and determine if immobilizing clinically suspected scaphoid fractures is supported by current evidence. This study also aimed to establish if there are predictors to assist in the diagnosis of a scaphoid fracture in the ED.

METHODS

A retrospective cohort study analyzed clinical data from patient's charts who attended the ED for a scaphoid fracture in 2019. Using retrospective patient chart audits and a Data Extraction Form, the clinical data regarding the assessment, treatment, diagnosis, and follow-up outcomes were collected. Descriptive analysis and multivariable logistic regression were performed to assess current management and find out predictors of a scaphoid fracture.

RESULTS

There was significance between practitioners performing physical assessments and providing treatment (P < .001). Physiotherapists performed assessment and education combined treatment more frequently than nurse practitioners and doctors. Thirty-four cases (11.7%) were negative for fracture in ED and positive in follow-up at the orthopedic clinic. There was an estimated loss of income of $327,433.60 (Australian dollar) for 221 patients who missed work due to overtreatment with immobilization. The strongest predictors for a confirmed scaphoid fracture were of male gender (odds ratio, 3.2; 95% confidence interval, 2.1-5.0; P < .001) and a positive x-ray in ED (odds ratio, 36.6; 95% confidence interval, 17.4-77.0; P < .001).

CONCLUSION

Management of scaphoid fractures across the Gold Coast Hospital Health Service ED followed commonly accepted practices involving x-ray and immobilization; however, this conservative approach to management is associated with increased health costs and low rates of conversion to a confirmed scaphoid fracture. Male gender was the only significant predictor associated with a scaphoid fracture.

Acute scaphoid fractures: making decisions for treating a troublesome bone

Seven aspects of the management of acute scaphoid fractures are open to debate: Diagnosis of true fractures among suspected fractures, assessment of fracture displacement, cast immobilization strategies, the role of surgical fixation, proximal pole fractures, assessment of union, and the underlying objective of treatment. We reviewed current evidence, and our varied interpretations of it, to highlight areas of uncertainty where more evidence might be helpful.

Diagnosis of Suspected Scaphoid Fractures

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Suspected scaphoid fractures are a diagnostic and therapeutic challenge despite the advances in knowledge regarding these injuries and imaging techniques. The risks and restrictions of routine immobilization as well as the restriction of activities in a young and active population must be weighed against the risks of nonunion that are associated with a missed fracture.

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The prevalence of true fractures among suspected fractures is low. This greatly reduces the statistical probability that a positive diagnostic test will correspond with a true fracture, reducing the positive predictive value of an investigation.

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There is no consensus reference standard for a true fracture; therefore, alternative statistical methods for calculating sensitivity, specificity, and positive and negative predictive values are required.

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Clinical prediction rules that incorporate a set of demographic and clinical factors may allow stratification of secondary imaging, which, in turn, could increase the pretest probability of a scaphoid fracture and improve the diagnostic performance of the sophisticated radiographic investigations that are available.

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Machine-learning-derived probability calculators may augment risk stratification and can improve through retraining, although these theoretical benefits need further prospective evaluation.

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Convolutional neural networks (CNNs) are a form of artificial intelligence that have demonstrated great promise in the recognition of scaphoid fractures on radiographs. However, in the more challenging diagnostic scenario of a suspected or so-called "clinical" scaphoid fracture, CNNs have not yet proven superior to a diagnosis that has been made by an experienced surgeon.

Delayed diagnosis of carpal scaphoid fracture in a young boy

Carpal scaphoid fracture is rare in children and is important to recognize early because of an increased risk for serious complications including non-union, avascular necrosis, and osteoarthritis. In the skeletally immature patient, a scaphoid fracture can easily escape detection due to clinical and diagnostic imaging interpretation errors. We report complete healing of a pediatric scaphoid non-union fracture after a remarkable delay in diagnosis and emphasize the considerable biological potential of the immature skeleton, coupled with proper stabilization, for good clinical outcomes.

Improved Detection of Scaphoid Fractures with High-Resolution Peripheral Quantitative CT Compared with Conventional CT

BACKGROUND

Computed tomography (CT), magnetic resonance imaging, and bone scintigraphy are second-line imaging techniques that are frequently used for the evaluation of patients with a clinically suspected scaphoid fracture. However, as a result of varying diagnostic performance results, no true reference standard exists for scaphoid fracture diagnosis. We hypothesized that the use of high-resolution peripheral quantitative CT (HR-pQCT) in patients with a clinically suspected scaphoid fracture could improve scaphoid fracture detection compared with conventional CT in the clinical setting.

METHODS

The present study included 91 consecutive patients (≥18 years of age) who presented to the emergency department with a clinically suspected scaphoid fracture between December 2017 and October 2018. All patients were clinically reassessed within 14 days after first presentation, followed by CT and HR-pQCT. If a scaphoid fracture was present, the fracture type was determined according to the Herbert classification system and correlation between CT and HR-pQCT was estimated with use of the Kendall W statistic or coefficient of concordance (W) (the closer to 1, the higher the correlation).

RESULTS

The cohort included 45 men and 46 women with a median age of 52 years (interquartile range, 29 to 67 years). HR-pQCT revealed a scaphoid fracture in 24 patients (26%), whereas CT revealed a scaphoid fracture in 15 patients (16%). Patients with a scaphoid fracture were younger and more often male. The correlation between CT and HR-pQCT was high for scaphoid fracture type according to the Herbert classification system (W = 0.793; 95% confidence interval [CI], 0.57 to 0.91; p < 0.001) and very high for scaphoid fracture location (W = 0.955; 95%, CI 0.90 to 0.98; p < 0.001).

CONCLUSIONS

In the present study, the number of patients diagnosed with a scaphoid fracture was 60% higher when using HR-pQCT as compared with CT. These findings imply that a substantial proportion of fractures-in this study, more than one-third-will be missed by the current application of CT scanning in patients with a clinically suspected scaphoid fracture.

LEVEL OF EVIDENCE

Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Has NICE guidance changed the management of the suspected scaphoid fracture: A survey of UK practice

INTRODUCTION

Despite scaphoid fractures being relatively uncommon pro-active treatment of suspected fractures has been seen as a risk management strategy. The poor positive predictive value of X-rays has led to published guidelines advocating MRI as a first-line or early imaging tool. It is unclear whether UK hospitals have been able to introduce early scanning and this national survey sought to establish the current management strategies for patients with a suspected scaphoid fracture.

METHOD

An electronic survey of UK emergency departments (ED) was conducted to establish the initial and follow up strategies for patients with negative imaging. Comparison of first and second-line imaging modalities was undertaken together with review of the clinical speciality responsible for ongoing management.

RESULTS

166 UK NHS Trusts were identified with emergency department facilities of which 66 (39.8%) responded. All sites perform an X-ray as the initial examination. For those with a negative examination ED follow up was the most common approach (54.6%), although many sites refer patients to other specialities including orthopaedics (39.4%) for follow up. The data demonstrated inconsistencies in the number of follow-up episodes and the different imaging investigations utilised. Frustration with the challenges presented by this patient cohort was evident.

CONCLUSION

The suspected scaphoid fracture represents an ongoing challenge to the NHS with many resource intensive pathways reliant on access to complex imaging investigations.

IMPLICATIONS FOR PRACTICE

Our study identified that UK Emergency Departments have limited early access to complex imaging for scanning of the scaphoid. A range of strategies are used for follow up of suspected scaphoid fractures and these are resource intensive. Overtreatment of patients with suspected scaphoid fracture is used as a risk management approach.

A Review on 3D-Printed Templates for Precontouring Fixation Plates in Orthopedic Surgery

This paper is a systematic review of the literature on 3D-printed anatomical replicas used as templates for precontouring the fixation plates in orthopedic surgery. Embase, PubMed, Cochrane, Scopus and Springer databases were consulted for information on design study, fracture anatomical location, number of patients, surgical technique, virtual modeling approach and 3D printing process. The initial search provided a total of 496 records. After removing the duplicates, the title and abstract screening, and applying exclusion criteria and citations searching, 30 papers were declared eligible and included in the final synthesis. Seven studies were identified as focusing on retrospective non-randomized series of clinical cases, while two papers presented randomized case control studies. Two main approaches were highlighted in developing 3D-printed anatomical models for precontouring fixation plates: (a.) medical reconstruction, virtual planning and fracture reduction followed by 3D printing the model; (b.) medical reconstruction followed by 3D printing the model of the mirrored uninjured side. Revised studies reported advantages such as surgical time and blood loss reduction, while the reduction quality is similar with that of the conventional surgery. During the last couple of years there was an increase in the number of studies focused on precontouring orthopedic plates using 3D printing technology. Three-dimensionally-printed templates for plate precontouring were mostly used for acetabular fractures. Knowledge on medical virtual modeling and reconstruction is mandatory.

The interobserver reliability of the diagnosis and classification of scaphoid fractures using high-resolution peripheral quantitative CT

Aims

Besides conventional radiographs, the use of MRI, CT, and bone scintigraphy is frequent in the diagnosis of a fracture of the scaphoid. However, which techniques give the best results remain unknown. The investigation of a new imaging technique initially requires an analysis of its precision. The primary aim of this study was to investigate the interobserver agreement of high-resolution peripheral quantitative CT (HR-pQCT) in the diagnosis of a scaphoid fracture. A secondary aim was to investigate the interobserver agreement for the presence of other fractures and for the classification of scaphoid fracture.

Methods

Two radiologists and two orthopaedic trauma surgeons evaluated HR-pQCT scans of 31 patients with a clinically-suspected scaphoid fracture. The observers were asked to determine the presence of a scaphoid or other fracture and to classify the scaphoid fracture based on the Herbert classification system. Fleiss kappa statistics were used to calculate the interobserver agreement for the diagnosis of a fracture. Intraclass correlation coefficients (ICCs) were used to assess the agreement for the classification of scaphoid fracture.

Results

A total of nine (29%) scaphoid fractures and 12 (39%) other fractures were diagnosed in 20 patients (65%) using HR-pQCT across the four observers. The interobserver agreement was 91% for the identification of a scaphoid fracture (95% confidence interval (CI) 0.76 to 1.00) and 80% for other fractures (95% CI 0.72 to 0.87). The mean ICC for the classification of a scaphoid fracture in the seven patients diagnosed with scaphoid fracture by all four observers was 73% (95% CI 0.42 to 0.94).

Conclusion

We conclude that the diagnosis of scaphoid and other fractures is reliable when using HR-pQCT in patients with a clinically-suspected fracture. Cite this article: Bone Joint J 2020;102-B(4):478–484.

Systematic Review of Diagnosis of Clinically Suspected Scaphoid Fractures

Background  Scaphoid fracture accounts for approximately 15% of acute wrist fractures. Clinical examination and plain X-rays are commonly used to diagnose the fracture, but this approach may miss up to 16% of fractures in the absence of clear-cut lucent lines on plain radiographs. As such, additional imaging may be required. It is not clear which imaging modality is the best. The goal of this study is to summarize the current literature on scaphoid fractures to evaluate the sensitivity, specificity, and accuracy of four different imaging modalities. Case Description  A systematic-review and meta-analysis was performed. The search term "scaphoid fracture" was used and all prospective articles investigating magnetic resonance imaging (MRI), computed tomography (CT), bone scintigraphy, and ultrasound were included. In total, 2,808 abstracts were reviewed. Of these, 42 articles investigating 51 different diagnostic tools in 2,507 patients were included. Literature Review  The mean age was 34.1 ± 5.7 years, and the overall incidence of scaphoid fractures missed on X-ray and diagnosed on advanced imaging was 21.8%. MRI had the highest sensitivity and specificity for diagnosing scaphoid fractures, which were 94.2 and 97.7%, respectively, followed by CT scan with a sensitivity and specificity at 81.5 and 96.0%, respectively. The sensitivity and specificity of ultrasound were 81.5 and 77.4%, respectively. Significant differences between MRI, bone scintigraphy, CT, and ultrasound were identified. Clinical Relevance  MRI has higher sensitivity and specificity than CT scan, bone scintigraphy, or ultrasound. Level of Evidence  This is a Level II systematic review.

Diagnostic accuracy of history taking, physical examination and imaging for phalangeal, metacarpal and carpal fractures: a systematic review update

BACKGROUND

The standard diagnostic work-up for hand and wrist fractures consists of history taking, physical examination and imaging if needed, but the supporting evidence for this work-up is limited. The purpose of this study was to systematically examine the diagnostic accuracy of tests for hand and wrist fractures.

METHODS

A systematic search for relevant studies was performed. Methodological quality was assessed and sensitivity (Se), specificity (Sp), accuracy, positive predictive value (PPV) and negative predictive value (NPV) were extracted from the eligible studies.

RESULTS

Of the 35 eligible studies, two described the diagnostic accuracy of history taking for hand and wrist fractures. Physical examination with or without radiological examination for diagnosing scaphoid fractures (five studies) showed Se, Sp, accuracy, PPV and NPV ranging from 15 to 100%, 13-98%, 55-73%, 14-73% and 75-100%, respectively. Physical examination with radiological examination for diagnosing other carpal bone fractures (one study) showed a Se of 100%, with the exception of the triquetrum (75%). Physical examination for diagnosing phalangeal and metacarpal fractures (one study) showed Se, Sp, accuracy, PPV and NPV ranging from 26 to 55%, 13-89%, 45-76%, 41-77% and 63-75%, respectively. Imaging modalities of scaphoid fractures showed predominantly low values for PPV and the highest values for Sp and NPV (24 studies). Magnetic Resonance Imaging (MRI), Computed Tomography (CT), Ultrasonography (US) and Bone Scintigraphy (BS) were comparable in diagnostic accuracy for diagnosing a scaphoid fracture, with an accuracy ranging from 85 to 100%, 79-100%, 49-100% and 86-97%, respectively. Imaging for metacarpal and finger fractures showed Se, Sp, accuracy, PPV and NPV ranging from 73 to 100%, 78-100%, 70-100%, 79-100% and 70-100%, respectively.

CONCLUSIONS

Only two studies were found on the diagnostic accuracy of history taking for hand and wrist fractures in the current review. Physical examination was of moderate use for diagnosing a scaphoid fracture and of limited use for diagnosing phalangeal, metacarpal and remaining carpal fractures. MRI, CT and BS were found to be moderately accurate for the definitive diagnosis of clinically suspected carpal fractures.

The Effect of Computed Tomography Scans Oriented Along the Longitudinal Scaphoid Axis on Measurements of Deformity and Displacement in Scaphoid Fractures

PURPOSE

Reformatting computed tomography (CT) scans along the scaphoid longitudinal axis improves the ability to detect scaphoid fractures compared with reformats along the wrist axis. However, it remains unclear whether scaphoid axis reformats affect measurements of displacement or deformity, which are factors that drive the clinical decision to perform open reduction internal fixation. Our null hypothesis was that reformatting CT scans along the scaphoid axis does not affect measurements of fracture displacement and deformity.

METHODS

Thirty patients with CT scans demonstrating scaphoid fractures (4 proximal pole, 17 midwaist fractures, and 9 distal) were identified and reformatted along 2 axes: the longitudinal axis of the scaphoid and the longitudinal axis of the wrist. The reformatted scans were sent to 2 musculoskeletal radiologists and 2 orthopedic hand surgeons who made the following measurements: (1) fracture gap, (2) displacement of the articular surface, (3) intrascaphoid angle, and (4) height to length (H:L) ratio.

RESULTS

The reliability of each of the measurements cited above was compared for all raters between the 2 axes using intraclass correlation coefficients. Measurement of fracture gap and articular displacement trended toward more reliability in the wrist axis, whereas measurement of H:L ratio and intrascaphoid angle trended toward more reliability in the scaphoid axis. However, no differences in measurements between the 2 axes were statistically significant.

CONCLUSIONS

This study demonstrates that reformatting CT scans in line with the axis of the scaphoid does not result in more reliable measurements of displacement or deformity.

CLINICAL RELEVANCE

Measurements of displacement and deformity in scaphoid fractures can be made in the wrist axis with comparative reliability to those in the longitudinal scaphoid axis.

Radiographic analysis of anatomic risk factors for scaphoid fractures; A case-control study

AIM

The purpose of this study was to investigate the role of anatomic variations in distal radius radiographic indices in patients with or without scaphoid fractures.

MATERIALS AND METHODS

Radial inclination (RI), volar tilt (VT), radial height (RH) and ulnar variance (UV) were measured on wrist radiographs of 320 patients with (Group I, n = 167) or without (Group II, n = 153) scaphoid fracture, fall on outstretched hand (FOOSH). Receiver operating characteristics (ROC) curve analysis was used to assess the diagnostic performance for each variable. Sensitivity (Sn), specificity (Sp), cutoff value, and area under the ROC curve were analyzed. Odds ratio was calculated for defined cutoff values.

RESULTS

The mean age of the groups was similar (29.3 ± 10.2 vs 31.1 ± 9.9 years, p = 0.060). RI (30.0 ± 2.9 vs 26.8 ± 2.3°) VT (11.4 ± 2.4 vs 10.5 ± 2.2°), RH (14.8 ± 2.1 vs 13.2 ± 1.9 mm), UV (-0.46 ± 1.7 vs 0.00 ± 1.5 mm) were higher in scaphoid fracture group (Gr I vs Gr II, p = 0.000, p = 0.000, p = 0.001, p = 0.012 respectively). Ulna minus variant was more prevalent in fracture group (p = 0.001). Optimal cutoff points for RI, VT, RH and UV in differentiating fractured and intact scaphoid were 28.6° (Sn = 81.0%, Sp = 26.3%), 12.2° (Sn = 80.4%, Sp = 67.1%), 14.85 mm (Sn = 80.4%, Sp = 52.1%) and 0 mm (Sn = 88.6%, Sp = 75.8%), respectively. Odds ratios for defined cutoff points for RI, VT, RH and UV were 10.4 (95% CI, 6.2-17.4), 1.8 (95% CI, 1.1-3.0), 3.7 (95% CI, 2.3-6.2) and 2.2 (95% CI, 1.3-3.7) respectively.

CONCLUSION

Increased RI, VT, RH and negative UV were found to be predisposing anatomical risk factors for scaphoid fracture when FOOSH.

Digital Tomography for Detection of Acute Occult Scaphoid Fractures

Diagnosis of occult scaphoid fractures remains a challenge. Traditional management consisting of 2 weeks of immobilization and repeat radiographs results in unnecessary immobilization of many patients without fracture. Magnetic resonance imaging (MRI) is sensitive but expensive. Digital tomography (DT) is an imaging technique that provides fine-cut visualization with minimal radiation exposure and may be used when there is high clinical suspicion despite negative findings on initial radiographs. The authors compared the ability of DT vs MRI to detect acute occult scaphoid fractures. This was an institutional review board-approved, prospective series. Adults for which clinical suspicion for acute scaphoid fracture (presenting within 96 hours of trauma) and negative findings on initial radiographs existed were included. Both a wrist tomogram and MRI were obtained. Wrists were immobilized and reevaluated at 10 to 14 days with repeat radiographs as a control. Studies were interpreted by a radiologist in a blinded fashion. Forty consecutive extremities in 39 patients met the inclusion criteria. Six (15%) of the 40 scaphoids were determined to be fractured on repeat radiographs. Digital tomogram yielded positive findings in 4 of these. Magnetic resonance imaging yielded positive findings in 8 (20%) of the 40 extremities. Sensitivities were 67% and 100% for digital tomogram and MRI, respectively (P=.0001). The positive predictive value was 100% for DT and MRI. The authors found that DT detects more occult scaphoid fractures than initial standard radiographs but is less sensitive than MRI. This is the first study to compare DT with MRI. Digital tomography can be used to augment radiographs and may increase diagnostic efficiency, minimize unnecessary immobilization, and reduce health care costs. [Orthopedics. 2017; 40(6):e1092-e1095.].

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.

Diagnosis of Occult Scaphoid Fractures: A Cost-Effectiveness Analysis

BACKGROUND

Scaphoid fractures are common but may be missed on initial radiographs. Advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) have improved diagnostic accuracy, but at an increased initial cost. The purpose of this study was to evaluate the cost-effectiveness of immediate advanced imaging for suspected occult scaphoid fractures.

METHODS

A decision analysis model was created to evaluate three diagnostic strategies for patients with concerning history and examination but negative radiographs: (1) empiric cast immobilization with orthopaedic follow-up and repeat radiography at two weeks post-injury, (2) immediate CT scanning, or (3) immediate MRI. Prevalence of occult scaphoid fracture, sensitivity and specificity of CT and MRI, and risks and outcomes of a missed fracture were derived from published clinical trials. Costs of imaging, lost worker productivity, and surgical costs of nonunion surgery were estimated on the basis of the literature.

RESULTS

Advanced imaging was dominant over empiric cast immobilization; advanced imaging had lower costs and its health outcomes were projected to be better than those of empiric cast immobilization. MRI was slightly more cost-effective than CT on the basis of the mean published diagnostic performance, but was highly sensitive to test performance characteristics. Advanced imaging would have to increase in cost to more than $2000 or decrease in sensitivity to <25% for CT or <32% for MRI for empiric cast immobilization to be cost-effective.

CONCLUSIONS

Given its relatively low cost and high diagnostic accuracy, advanced imaging for suspected scaphoid fractures in the setting of negative radiographs represents a cost-effective strategy for reducing both costs and morbidity. The decision to use CT compared with MRI is a function of individual institutional costs and local test performance characteristics.

Computed tomography versus magnetic resonance imaging versus bone scintigraphy for clinically suspected scaphoid fractures in patients with negative plain radiographs

BACKGROUND

In clinically suspected scaphoid fractures, early diagnosis reduces the risk of non-union and minimises loss in productivity resulting from unnecessary cast immobilisation. Since initial radiographs do not exclude the possibility of a fracture, additional imaging is needed. Computed tomography (CT), magnetic resonance imaging (MRI) and bone scintigraphy (BS) are widely used to establish a definitive diagnosis, but there is uncertainty about the most appropriate method.

OBJECTIVES

The primary aim of this study is to identify the most suitable diagnostic imaging strategy for identifying clinically suspected fractures of the scaphoid bone in patients with normal radiographs. Therefore we looked at the diagnostic performance characteristics of the most used imaging modalities for this purpose: computed tomography, magnetic resonance imaging and bone scintigraphy.

SEARCH METHODS

In July 2012, we searched the Cochrane Register of Diagnostic Test Accuracy Studies, MEDLINE, EMBASE, the Database of Abstracts of Reviews of Effects, the Cochrane Central Register of Controlled Trials, the NHS Economic Evaluation Database. In September 2012, we searched MEDION, ARIF, Current Controlled Trials, the World Health Organization (WHO) International Clinical Trials Registry Platform, conference proceedings and reference lists of all articles.

SELECTION CRITERIA

We included all prospective or retrospective studies involving a consecutive series of patients of all ages that evaluated the accuracy of BS, CT or MRI, or any combination of these, for diagnosing suspected scaphoid fractures. We considered the use of one or two index tests or six-week follow-up radiographs as adequate reference standards.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts and assessed full-text reports of potentially eligible studies. The same authors extracted data from full-text reports and assessed methodological quality using the QUADAS checklist. For each index test, estimates of sensitivity and specificity from each study were plotted in ROC space; and forest plots were constructed for visual examination of variation in test accuracy. We performed meta-analyses using the HSROC model to produce summary estimates of sensitivity and specificity.

MAIN RESULTS

We included 11 studies that looked at diagnostic accuracy of one or two index tests: four studies (277 suspected fractures) looked at CT, five studies (221 suspected fractures) looked at MRI and six studies (543 suspected fractures) looked at BS. Four of the studies made direct comparisons: two studies compared CT and MRI, one study compared CT and BS, and one study compared MRI and BS. Overall, the studies were of moderate to good quality, but relevant clinical information during evaluation of CT, MRI or BS was mostly unclear or unavailable.As few studies made direct comparisons between tests with the same participants, our results are based on data from indirect comparisons, which means that these results are more susceptible to bias due to confounding. Nonetheless, the direct comparisons showed similar patterns of differences in sensitivity and specificity as for the pooled indirect comparisons.Summary sensitivity and specificity of CT were 0.72 (95% confidence interval (CI) 0.36 to 0.92) and 0.99 (95% CI 0.71 to 1.00); for MRI, these were 0.88 (95% CI 0.64 to 0.97) and 1.00 (95% CI 0.38 to 1.00); for BS, these were 0.99 (95% CI 0.69 to 1.00) and 0.86 (95% CI 0.73 to 0.94). Indirect comparisons suggest that diagnostic accuracy of BS was significantly higher than CT and MRI; and CT and MRI have comparable diagnostic accuracy. The low prevalence of a true fracture among suspected fractures (median = 20%) means the lower specificity for BS is problematic. For example, in a cohort of 1000 patients, 112 will be over-treated when BS is used for diagnosis. If CT is used, only 8 will receive unnecessary treatment. In terms of missed fractures, BS will miss 2 fractures and CT will miss 56 fractures.

AUTHORS' CONCLUSIONS

Although quality of the included studies is moderate to good, findings are based on only 11 studies and the confidence intervals for the summary estimates are wide for all three tests. Well-designed direct comparison studies including CT, MRI and BS could give valuable additional information.Bone scintigraphy is statistically the best diagnostic modality to establish a definitive diagnosis in clinically suspected fractures when radiographs appear normal. However, physicians must keep in mind that BS is more invasive than the other modalities, with safety issues due to level of radiation exposure, as well as diagnostic delay of at least 72 hours. The number of overtreated patients is substantially lower with CT and MRI.Prior to performing comparative studies, there is a need to raise the initially detected prevalence of true fractures in order to reduce the effect of the relatively low specificity in daily practice. This can be achieved by improving clinical evaluation and initial radiographical assessment.

Emergency department evaluation and treatment of wrist injuries

Correct diagnosis of wrist injuries is critical in preventing prolonged pain and dysfunction. Radiographs cannot diagnose a large percentage of injuries. Wrist sprain is considered one of the most common yet most treacherous emergency department (ED) diagnoses because radiographs do not always rule out all acute injuries. Knowledge of the anatomy, normal physical examination findings, and physical examination abnormalities associated with different pathological conditions, is paramount in making the correct diagnosis. This article focuses on the anatomy, diagnosis, and ED management of acute wrist injuries, including fractures and dislocations.

Prevalence and clinical significance of occult fractures in children with radiograph-negative acute ankle injury. A meta-analysis

BACKGROUND AND PURPOSE

Plain radiographs may fail to reveal an ankle fracture in children because of developmental and anatomical characteristics. In this systematic review and meta- analysis, we estimated the prevalence of occult fractures in children with acute ankle injuries and clinical suspicion of fracture, and assessed the diagnostic accuracy of ultrasound (US) in the detection of occult fractures.

METHODS

We searched the literature and included studies reporting the prevalence of occult fractures in children with acute ankle injuries and clinical suspicion of fracture. Proportion meta-analysis was performed to calculate the pooled prevalence of occult fractures. For each individual study exploring the US diagnostic accuracy, we calculated US operating characteristics.

RESULTS

9 studies (involving 187 patients) using magnetic resonance imaging (MRI) (n = 5) or late radiographs (n = 4) as reference standard were included, 2 of which also assessed the diagnostic accuracy of US. Out of the 187 children, 41 were found to have an occult fracture. The pooled prevalence of occult fractures was 24% (95% CI: 18-31). The operating characteristics for detection of occult ankle fractures by US ranged in positive likelihood ratio (LR) from 9 to 20, and in negative LR from 0.04 to 0.08.

INTERPRETATION

A substantial proportion of fractures may be overlooked on plain radiographs in children with acute ankle injuries and clinical suspicion of fracture. US appears to be a promising method for detection of ankle fractures in such children when plain radiographs are negative.

Computed tomography for suspected scaphoid fractures: comparison of reformations in the plane of the wrist versus the long axis of the scaphoid

BACKGROUND

Definitive diagnosis of occult scaphoid fractures remains difficult. We tested the null hypothesis that, for diagnosis of true fractures among suspected scaphoid fractures, computed tomography (CT) reformations along the long axis of the scaphoid have the same accuracy as reformations made relative to the anatomical planes of the wrist.

METHODS

In a prospective trial, 34 patients with a suspected scaphoid fracture underwent CT scanning within 10 days after trauma. CT reformations along the long axis of the scaphoid (CT-scaphoid) and along planes relative to the wrist (CT-wrist) were made. We used radiographs obtained 6 weeks after injury as the reference standard for a true fracture. A blinded panel including two surgeons and one radiologist came to a consensus diagnosis for each reformation plane.

RESULTS

The reference standard showed six fractures of the scaphoid (prevalence, 18 %). Using CT-wrist, a scaphoid fracture was diagnosed in five patients (15 %), with three false positive, four false negative and two true positive diagnoses. Using CT-scaphoid, a scaphoid fracture was diagnosed in five patients (15 %), with one false positive, two false negative and four true positive results. Sensitivity, specificity and accuracy were 33, 89 and 79 % for CT-wrist and 67, 96 and 91 % for CT-scaphoid, respectively. This resulted in positive predictive values of 36 % for CT-wrist and 76 % for CT-scaphoid. Negative predictive values were 87 % for CT-wrist and 94 % for CT-scaphoid. No significant differences were found with the number of patients available.

CONCLUSIONS

For diagnosis of true fractures among suspected scaphoid fractures, the diagnostic performance characteristics of CT scans reformatted along the long axis of the scaphoid were better than CT scans in the planes of the wrist, but the differences were not significant.

Adult scaphoid fracture

OBJECTIVES

Scaphoid fractures are the most common carpal fracture, representing 70% of carpal bone fractures. The diagnostic accuracy of physical examination findings and emergency medicine (EM) imaging studies for scaphoid fracture has not been previously described in the EM literature. Plain x-rays are insufficient to rule out scaphoid fractures in a patient with a suggestive mechanism and radial-sided tenderness on physical examination. This study was a meta-analysis of historical features, physical examination findings, and imaging studies for scaphoid fractures not visualized on plain x-ray in adult emergency department (ED) patients, specifically to address which types of imaging tests should be recommended in patients with persistent concern for acute fracture after ED discharge.

METHODS

A medical librarian and two emergency physicians (EPs) conducted a medical literature search of PUBMED and EMBASE. The original studies' bibliographies were reviewed for additional references and unpublished manuscripts were located via a hand search of EM research abstracts from national meetings. All abstracts were independently reviewed by the two physicians, and Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2) was used to assess individual study quality. When two or more qualitatively similar studies were identified, meta-analysis was conducted using Meta-DiSc software. Primary outcomes were sensitivity, specificity, and likelihood ratios (LRs) for predictors of scaphoid fracture detected on follow-up in patients with normal ED x-rays.

RESULTS

A total of 957 unique citations were identified, yielding 75 studies eligible for inclusion in this systematic review. Studies were significantly heterogeneous in design, study population, and criterion standard. The majority of studies were conducted in non-ED settings (e.g., orthopedic clinics). No studies used accepted diagnostic research publishing guidelines, and the overall QUADAS-2 methodologic quality was low, indicating an increased risk of bias in the estimates of diagnostic accuracy. The prevalence of scaphoid fractures ranged from 12% to 57% with the point estimate of 25% pretest probability for adult ED patients with concern for scaphoid injuries, nondiagnostic index x-rays, and scaphoid fractures on later imaging studies. Except for the absence of snuffbox tenderness (LR- = 0.15), physical examination findings lack accuracy to rule in or rule out scaphoid fractures, and no validated clinical decision rules exist. In patients with persistent concern for injury, magnetic resonance imaging (MRI) is superior to bone scan, computed tomography (CT), or ultrasound (US) to both rule in and rule out scaphoid fractures. Both MRI and CT share the added benefit of identifying alternative etiologies for posttraumatic wrist pain.

CONCLUSIONS

Except for the absence of snuffbox tenderness, which can significantly reduce the probability of scaphoid fracture, history and physical examination alone are inadequate to rule in or rule out scaphoid fracture. MRI is the most accurate imaging test to diagnose scaphoid fractures in ED patients with no evidence of fracture on initial x-rays. If MRI is unavailable, CT is adequate to rule in scaphoid fractures, but inadequate for ruling out scaphoid fractures.

The scaphoid

The scaphoid is vitally important for the proper mechanics of wrist function. Its unique morphology from its boat like shape to its retrograde blood supply can present with challenges in the presence of a fracture. Almost completely covered with articular cartilage, this creates precise surface loading demands and intolerance to bony remodeling. Fracture location compounds risk of malunion and non-union. Scaphoid fractures may significantly impair wrist function and activities of daily living, with both individual and economic consequences.

Interobserver variability among radiologists for diagnosis of scaphoid fractures by computed tomography

PURPOSE

To determine the interobserver variability among radiologists for computed tomography (CT) diagnosis of scaphoid fractures.

METHODS

Four specialized musculoskeletal radiologists evaluated the CT scans of 150 consecutive patients who were clinically suspected of having sustained a scaphoid fracture but whose scaphoid-specific radiographs were normal. The radiologists were asked to determine the presence or absence of a scaphoid fracture and to localize the fracture. Interobserver agreement was calculated using the kappa statistic.

RESULTS

The radiologists diagnosed between 11 (7%) and 22 (15%) scaphoid fractures; the kappa value was 0.51.

CONCLUSION

Agreement on the presence of a scaphoid fracture and its location on a CT scan was moderate among the 4 radiologists. This finding raises the question as to whether scaphoid fractures could be under- or overdiagnosed in daily practice when CT is used to exclude or confirm a fracture. This should be kept in mind when interpreting clinical and radiological results in patients with suspected scaphoid fractures.

Predictors of fracture following suspected injury to the scaphoid

A prospective study was performed to develop a clinical prediction rule that incorporated demographic and clinical factors predictive of a fracture of the scaphoid. Of 260 consecutive patients with a clinically suspected or radiologically confirmed scaphoid fracture, 223 returned for evaluation two weeks after injury and formed the basis of our analysis. Patients were evaluated within 72 hours of injury and at approximately two and six weeks after injury using clinical assessment and standard radiographs. Demographic data and the results of seven specific tests in the clinical examination were recorded. There were 116 (52%) men and their mean age was 33 years (13 to 95; SD 17.9). In 62 patients (28%) a scaphoid fracture was confirmed. A logistic regression model identified male gender (p = 0.002), sports injury (p = 0.004), anatomical snuff box pain on ulnar deviation of the wrist within 72 hours of injury (p < 0.001), and scaphoid tubercle tenderness at two weeks (p < 0.001) as independent predictors of fracture. All patients with no pain at the anatomical snuff box on ulnar deviation of the wrist within 72 hours of injury did not have a fracture (n = 72, 32%). With four independently significant factors positive, the risk of fracture was 91%. Our study has demonstrated that clinical prediction rules have a considerable influence on the probability of a suspected scaphoid fracture. This will help improve the use of supplementary investigations where the diagnosis remains in doubt.

Diagnostic accuracy of imaging modalities for suspected scaphoid fractures

Follow-up radiographs are usually used as the reference standard for the diagnosis of suspected scaphoid fractures. However, these are prone to errors in interpretation. We performed a meta-analysis of 30 clinical studies on the diagnosis of suspected scaphoid fractures, in which agreement data between any of follow-up radiographs, bone scintigraphy, magnetic resonance (MR) imaging, or CT could be obtained, and combined this with latent class analysis to infer the accuracy of these tests on the diagnosis of suspected scaphoid fractures in the absence of an established standard. The estimated sensitivity and specificity were respectively 91.1% and 99.8% for follow-up radiographs, 97.8% and 93.5% for bone scintigraphy, 97.7% and 99.8% for MRI, and 85.2% and 99.5% for CT. The results were generally robust in multiple sensitivity analyses. There was large between-study heterogeneity for the sensitivity of follow-up radiographs and CT, and imprecision about their sensitivity estimates.

If we acknowledge the lack of a reference standard for diagnosing suspected scaphoid fractures, MRI is the most accurate test; follow-up radiographs and CT may be less sensitive, and bone scintigraphy less specific.

Early CT for suspected occult scaphoid fractures

In this study, the use of computed tomography (CT) early in the management of suspected occult scaphoid fractures was evaluated. We retrospectively reviewed the notes and radiology of patients who had scaphoid CT scans over the preceding 3 years. Eighty-four patients that had CT scans within 14 days from injury were identified. Of the CT scans, 64% (n = 54) excluded a fracture and these patients were promptly mobilized. No patients returned with any complications from this management. Overall, 36% of CT scans were abnormal (n = 30), 7% revealed occult scaphoid fractures, 18% revealed occult carpal fractures of the triquetrum, capitate, and lunate, respectively, and 5% revealed distal radius fractures. All patients diagnosed with fractures were successfully managed with plaster immobilization and there was one case of complex regional pain syndrome. Early CT alters therapeutic decision making in suspected occult fractures preventing unnecessary immobilization in a working population without increase in cost.

Diagnostic performance tests for suspected scaphoid fractures differ with conventional and latent class analysis

BACKGROUND

Evaluation of the diagnostic performance characteristics of radiographic tests for diagnosing a true fracture among suspected scaphoid fractures is hindered by the lack of a consensus reference standard. Latent class analysis is a statistical method that takes advantage of unobserved, or latent, classes in the data that can be used to determine diagnostic performance characteristics when there is no consensus reference (gold) standard.

PURPOSES

We therefore compared the diagnostic performance characteristics of MRI, CT, bone scintigraphy, and physical examination to identify true fractures among suspected scaphoid fractures.

PATIENTS AND METHODS

We used data from two studies, one that prospectively studied 34 patients who had MRI and CT of the wrist, and a second that studied 78 patients who had MRI, bone scintigraphy, and structured physical examination. We compared the diagnostic performance characteristics calculated by latent class analysis with those calculated using formulas based on a reference standard.

RESULTS

In the first cohort, the calculated sensitivity and specificity with latent class analysis were different than those with traditional reference standard-based calculations for the CT in the scaphoid planes (sensitivity, 0.78 versus 0.67; specificity, 1.0 versus 0.96) and the MRI (sensitivity, 0.80 versus 0.67; specificity, 0.93 versus 0.89). In the second cohort, the greatest differences were in the sensitivity of MRI (0.84 versus 0.75) and the sensitivities of physical examination maneuvers (range, 0.63-0.73 versus 1.0).

CONCLUSIONS

The diagnostic performance characteristics calculated using latent class analysis may differ from those calculated according to formulas based on a reference standard. We believe latent class analysis merits further study as an option for assessing diagnostic performance characteristics for orthopaedic conditions when there is no consensus reference standard.

LEVEL OF EVIDENCE

Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

[Analysis of the management of occult fractures of the scaphoid through early magnetic resonance imaging]

INTRODUCTION

We aimed to evaluate the usefulness of magnetic resonance imaging (MRI) in the diagnosis of occult fractures of the scaphoid and to determine the advantages and cost in comparison with the traditional follow-up protocol.

MATERIAL AND METHOD

The traditional approach at our center consisted of immobilization and periodic clinical and radiological follow-up (plain-film X-rays and computed tomography in the final phase of the process). The new protocol called for a limited MRI study consisting of coronal T1- and T2-weighted fat suppression sequences if the findings at plain-film X-rays continued to be negative at the first follow-up examination with the traumatologist (10 days after trauma). We evaluated the MRI findings, the time the patient was immobilized, the cost of each protocol, and the dose of radiation received.

RESULTS

We included 33 cases of patients with clinically suspected fractures of the scaphoid and negative findings on plain-film X-rays. In 13 patients, the MRI findings were negative. In 12 patients, the MRI findings confirmed the diagnosis of a fracture of the scaphoid, which was associated with other pathology in 6 cases. In 8 patients, another pathological process was diagnosed. The cost of the new protocol was €131.06 per patient; the cost of the traditional protocol was €114.41 or €151.06 per patient, depending on the follow-up studies required. The new protocol reduced the dose of radiation by eliminating successive radiologic studies.

CONCLUSIONS

The new protocol improved the management of these patients, reducing the time of immobilization, improving joint rigidity, and reducing the time off work. The limited MRI study makes it possible to diagnose other radiologically occult lesions. The cost of the new protocol is similar to that of the traditional protocol and even lower in some cases. The new protocol results in a reduction in the dose of radiation.

Role of MRI in the diagnosis and management of patients with clinical scaphoid fracture

PURPOSE

The American College of Radiologists (ACR) recognises the value of magnetic resonance imaging (MRI) as the investigation of choice in patients with a clinically suspected scaphoid fracture but normal plain radiographs. The Royal College of Radiologists (RCR) in the UK produces no similar guidelines, as evidenced by the inconsistent management of such cases in hospitals around the UK. In discussion with our musculoskeletal radiologists, we implemented new guidelines to standardise management of our patients and now report our findings.

METHODS

A consecutive series of 137 patients referred to the orthopaedic department with clinically suspected scaphoid fracture but normal series of plain radiographs were prospectively followed up over a two-year period. We implemented the use of early MRI for these patients and determined its incidence of detected scaphoid injury in addition to other occult injuries. We then prospectively examined results of these findings on patient management.

RESULTS

Thirty-seven (27%) MRI examinations were normal with no evidence of a bony or soft-tissue injury. Soft-tissue injury was diagnosed in 59 patients (43.4%). Of those, 46 were triangular fibrocartilage complex (TFCC) tears (33.8%) and 18 were intercarpal ligament injuries (13.2 %). Bone marrow oedema with no distinct fracture was discovered in 55 cases (40.4%). In 17 (12.5%) cases, this involved only the scaphoid. In the remainder, it also involved the other carpal bones or distal radius. Fracture(s) were diagnosed on 30 examinations (22.0%).

CONCLUSIONS

MRI should be regarded as the gold standard investigation for patients in whom a scaphoid fracture is suspected clinically. It allows the diagnosis of occult bony and soft-tissue injuries that can present clinically as a scaphoid fracture; it also helps exclude patients with no fracture. We believe that there is a need to implement national guidelines for managing occult scaphoid fractures.

Delays and poor management of scaphoid fractures: factors contributing to nonunion

PURPOSE

Scaphoid fracture nonunion remains prevalent, and it was our purpose to examine the initial care, fracture site, and patient gender and age to determine factors contributing to fracture nonunion.

METHODS

The charts of 96 consecutive patients with 99 scaphoid fracture nonunions were reviewed for demographic information, and contact was made with 85 patients (with 88 scaphoid nonunions) to determine the pattern of presentation and initial treatment, if any.

RESULTS

Of the 88 scaphoid nonunions, 78 were in men, and 46 were sports injuries; 7 patients had no recollection of an injury. Twenty were proximal pole fractures. For 57 fractures, patients sought care following their injury, but only 42 were diagnosed with scaphoid fractures and received appropriate treatment, although one did not follow up in the clinic. Fifteen patients with nonunions did not receive radiographic investigations or did not have an identifiable fracture on initial x-rays and received no further follow-up or treatment. For 27 nonunions, medical attention was sought but was delayed, with an average time of 57 days between injury and initial assessment. For 31 fractures, medical attention was not sought for the acute injury but presented later following a re-injury (17 nonunions) or with progressive pain or stiffness (13 nonunions).

CONCLUSIONS

The high rates of delayed presentation and incomplete evaluation and treatment suggest a strong need for better patient and doctor education on the subject of scaphoid injuries and nonunions particularly because the initial injury is, unfortunately, sometimes perceived as trivial. Nonunions do occur despite appropriate immobilization. Proximal pole fractures and fractures that show inadequate progression toward union while being treated in a cast should be considered for surgical intervention based on the high number of such cases identified in this study.

Occult fractures of the scaphoid: the role of ultrasonography in the emergency department

OBJECTIVE

To evaluate ultrasonography (US) performed by an emergency radiologist in patients with clinical suspicion of scaphoid fracture and normal radiographs.

MATERIALS AND METHODS

Sixty-two consecutive adult patients admitted to our emergency department with clinical suspicion of scaphoid fracture and normal radiographs underwent US examination of the scaphoid prior to wrist computed tomography (CT), within 3 days following wrist trauma. US examination was performed by a board-certified emergency radiologist, non-specialized in musculoskeletal imaging, using the linear probe (5-13 MHz) of the standard sonographic equipment of the emergency department. The radiologist evaluate for the presence of a cortical interruption of the scaphoid along with a radio-carpal or scapho-trapezium-trapezoid effusion. A CT of the wrist (reference standard) was performed in every patient, immediately after ultrasonography. Fractures were classified into two groups according to their potential for complication: group 1 (high potential, proximal or waist), group 2 (low-potential, distal or tubercle).

RESULTS

A scaphoid fracture was demonstrated by CT in 13 (21%) patients: eight (62%) of them belonged to group 1 (three in the proximal pole, five in the waist), five (38%) to group 2 (three in the distal part, two in the tubercle). US was 92% sensitive (12/13) in demonstrating a scaphoid fracture. It was 100% sensitive (8/8) in demonstrating a fracture with a high potential of complication (group 1).

CONCLUSIONS

Our data show that, in emergency settings, US can be used for the triage to CT in patients with clinical suspicion of scaphoid fracture and normal radiographs.

Assessment of the suspected fracture of the scaphoid

A suspected fracture of the scaphoid remains difficult to manage despite advances in knowledge and imaging methods. Immobilisation and restriction of activities in a young and active patient must be balanced against the risks of nonunion associated with an undiagnosed and undertreated fracture of the scaphoid.

The assessment of diagnostic tests for a suspected fracture of the scaphoid must take into account two important factors. First, the prevalence of true fractures among suspected fractures is low, which greatly reduces the probability that a positive test will correspond with a true fracture, as false positives are nearly as common as true positives. This situation is accounted for by Bayesian statistics. Secondly, there is no agreed reference standard for a true fracture, which necessitates the need for an alternative method of calculating diagnostic performance characteristics, based upon a statistical method which identifies clinical factors tending to associate (latent classes) in patients with a high probability of fracture.

The most successful diagnostic test to date is MRI, but in low-prevalence situations the positive predictive value of MRI is only 88%, and new data have documented the potential for false positive scans. The best strategy for improving the diagnosis of true fractures among suspected fractures of the scaphoid may well be to develop a clinical prediction rule incorporating a set of demographic and clinical factors which together increase the pre-test probability of a fracture of the scaphoid, in addition to developing increasingly sophisticated radiological tests.

Diagnostic accuracy of multidetector computed tomography for patients with suspected scaphoid fractures and negative radiographic examinations

PURPOSE

The aim of this prospective study was to evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) in detecting occult scaphoid fractures.

MATERIALS AND METHODS

A total of 54 patients with a clinically suspected scaphoid fracture and negative initial conventional radiographs were evaluated with 64-row MDCT wrist examinations within 1 week of the trauma. The gold standard used was the diagnosis on MRI done within 1 week after MDCT. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDCT were calculated.

RESULTS

MRI showed a total of 22 fractures in 20 of 55 (36%) wrists. Fractures included 14 scaphoid and 8 other carpal bones. MDCT showed a total of 19 fractures in 17 of 55 (30%) wrists. Two isolated scaphoid fractures and one trapezium fracture were missed on MDCT. The sensitivity, specificity, PPV, and NPV of MDCT were 86%, 100%, 100%, and 91%, respectively.

CONCLUSION

MDCT offers highly accurate results, especially concerning cortical involvement, and is a useful alternative in facilities lacking MRI.

Comparison of CT and MRI for diagnosis of suspected scaphoid fractures

BACKGROUND

There is no consensus on the optimum imaging method to use to confirm the diagnosis of true scaphoid fractures among patients with suspected scaphoid fractures. This study tested the null hypothesis that computed tomography (CT) and magnetic resonance imaging (MRI) have the same diagnostic performance characteristics for the diagnosis of scaphoid fractures.

METHODS

Thirty-four consecutive patients with a suspected scaphoid fracture (tenderness of the scaphoid and normal radiographic findings after a fall on the outstretched hand) underwent CT and MRI within ten days after a wrist injury. The reference standard for a true fracture of the scaphoid was six-week follow-up radiographs in four views. A panel including surgeons and radiologists came to a consensus diagnosis for each type of imaging. The images were considered in a randomly ordered, blinded fashion, independent of the other types of imaging. We calculated sensitivity, specificity, and accuracy as well as positive and negative predictive values.

RESULTS

The reference standard revealed six true fractures of the scaphoid (prevalence, 18%). CT demonstrated a fracture in five patients (15%), with one false-positive, two false-negative, and four true-positive results. MRI demonstrated a fracture in seven patients (21%), with three false-positive, two false-negative, and four true-positive results. The sensitivity, specificity, and accuracy were 67%, 96%, and 91%, respectively, for CT and 67%, 89%, and 85%, respectively, for MRI. According to the McNemar test for paired binary data, these differences were not significant. The positive predictive value with use of the Bayes formula was 0.76 for CT and 0.54 for MRI. The negative predictive value was 0.94 for CT and 0.93 for MRI.

CONCLUSIONS

CT and MRI had comparable diagnostic characteristics. Both were better at excluding scaphoid fractures than they were at confirming them, and both were subject to false-positive and false-negative interpretations. The best reference standard is debatable, but it is now unclear whether or not bone edema on MRI and small unicortical lines on CT represent a true fracture.

The emergent evaluation and treatment of hand and wrist injuries

The anatomy of the hand is complex, which allows for the dexterity, strength, and adaptability of the most functional aspect of the musculoskeletal system. The evaluation and management of injuries to this area can be time consuming and pose a significant medicolegal risk to the emergency physician. Improperly diagnosed and managed injuries can lead to chronic pain, inability to perform activities of daily living, and even seemingly minor injuries can lead to missed work causing a significant cost to the individual and society. The purpose of this article is to review injuries to the hand and wrist and discuss diagnostic studies and treatment plans that the emergency physician can use to treat patients effectively and minimize their exposure to risk.

Clinical prediction rule for suspected scaphoid fractures: A prospective cohort study

BACKGROUND

The low prevalence of true fractures amongst suspected fractures magnifies the shortcomings of the diagnostic tests used to triage suspected scaphoid fractures.

PURPOSE

The objective was to develop a clinical prediction rule that would yield a subset of patients who were more likely to have a scaphoid fracture than others who lacked the subset criteria.

METHODS

Seventy-eight consecutive patients diagnosed with a suspected scaphoid fracture were included. Standardised patient history, physical examination, range of motion (ROM) and strength measurements were studied. The reference standard for a true fracture was based on the results of magnetic resonance imaging, bone scintigraphy, follow-up radiographs and examination.

RESULTS

Analysis revealed three significant independent predictors: extension <50%, supination strength ≤ 10% and the presence of a previous fracture.

CONCLUSION

Clinical prediction rules have the potential to increase the prevalence of true fractures amongst patients with suspected scaphoid fractures, which can increase the diagnostic performance characteristics of radiological diagnostic tests used for triage.

Management of late-diagnosed scaphoid fractures

BACKGROUND

Scaphoid fractures are among the most common types of carpal bone injury; they can be easily overlooked in the acute stage. Scaphoid fractures detected in the subacute stage require a more meticulous and prompt approach, to prevent chronicity and regain wrist function.

METHODS

The records of 30 patients were selected from 97 with scaphoid fractures surgically treated between 1994 and 2002. Fractures that were diagnosed between 2 weeks and 5 months (average, 2.2 months) after the injury were included. We report the fracture patterns and locations, as determined from radiographs, as well as the surgical methods used. The mean follow-up was 2.5 years.

RESULTS

Oblique fractures (60%) were the most commonly overlooked fractures. Twenty-six patients (87%) underwent open surgery, and 23 (77%) required bone grafts. Percutaneous fixation was indicated for only four patients, whose fractures were reducible via either fluoroscopic or arthroscopic guidance. Osseous unions were achieved for 29 (97%) patients; these patients returned to their pre-injury level of activity. The average union time was 10.6 weeks.

CONCLUSION

Oblique-type scaphoid fractures are potentially unstable and may result in detrimental sequelae if overlooked in the acute stage. Accurate diagnosis is possible through critical skepticism and the meticulous scrutiny of radiographs. Prompt surgical intervention is associated with promising outcomes.