Impact of clinical history on radiographic detection of fractures: a comparison of radiologists and orthopedists

Are the methods used by radiologists in interpreting imaging studies different from those of attending physicians? We evaluated the influence that knowledge of localizing clinical signs has on the accuracy of fracture detection by orthopedic surgeons and compared the results with those of an identical study of radiologists performed earlier. The orthopedists studied had the same degree of experience as the radiologists. Forty radiographs of the extremities were examined twice by seven orthopedic surgeons. In 26 cases, a subtle fracture was present; 14 cases were normal. During one interpretation of the radiographs of each case, the precise location of pain, tenderness, or swelling was provided; during the other, this information was withheld. Analysis of receiver-operating-characteristic parameters indicates that the clues regarding location of trauma facilitate detection of fractures by orthopedists (an 11% improvement in Az, the area under the ROC curve, F[1,12] = 49.67, p less than .001). This finding is similar to the results of the earlier study with radiologists (a 6% improvement in Az, F[1,12] = 14.77, p less than .005). Statistical comparison of the two experiments showed that orthopedists depend on this information much more than do radiologists, demonstrated by a statistically significant prompting-by-specialty interaction (F[1,12] = 5.13, p less than .05). Localization clues improve ability of orthopedic surgeons to detect fractures in the trauma patient even more than they improve the ability of radiologists. The accuracy of the radiologist will suffer less than that of the orthopedist when localization clues are unavailable. Nonetheless, the findings show that localizing clues are important to both orthopedists and radiologists when searching for fractures.     

A careful evaluation of scout CT lateral radiograph may prevent unreported vertebral fractures

Objectives

Our purpose was to review scout CT lateral radiographs to reveal osteoporotic vertebral fractures unreported by radiologists and to explore scout CT as a potential diagnostic tool in the detection of vertebral fractures.

Methods

We considered 500 patients (303 males, 197 females, age 64.6 ± 13.5 year-old). Our investigation was firstly focused on scout CT lateral images to detect vertebral fractures with a combined semiquantitative and quantitative diagnostic approach. Findings addressed to vertebral fracture were subsequently confirmed by multiplanar sagittal CT reconstructions. Whenever a vertebral fracture was discovered the radiologist report was read and a collection of patient anamnesis followed to understand whether fractures were already known.

Results

In 44/500 patients (8.8%) the evaluation on scout CT was incomplete or limited for patient/technical-based conditions, and 15 were excluded from the analysis. In 67/485 patients (13.8%) 99 vertebral fractures were detected. Among 67 fractured patients only 18 (26.9%) were previously diagnosed by radiologists. However, in the clinical history of 32 patients vertebral fractures were already known.

Conclusions

The perception and sensibility to vertebral fractures among radiologists are still poor when the assessment of the spine is not the aim of the examination. Short time spent for the evaluation of scout CT lateral radiographs could improve our accuracy.     

Gaze dwell times on acute trauma injuries missed because of satisfaction of search

RATIONALE AND OBJECTIVES: The authors performed this study to determine whether satisfaction of search (SOS) errors in patients with multiple traumas are caused by faulty visual scanning, faulty recognition, or faulty decision making. MATERIALS AND METHODS: A series of radiographs were obtained in patients with multiple traumas. Radiologists interpreted each series under two experimental conditions: when the first radiograph in the series included a fracture, and when it did not. In the first experiment, the initial radiographs showed nondisplaced fractures of the extremities (minor fractures); in the second experiment, the initial radiographs showed abnormalities of greater clinical importance (major fractures). Each series also included a radiograph with a subtle (test) fracture and a normal radiograph on which detection accuracy was measured. In each experiment, gaze dwell time was recorded as 10 radiologists reviewed images from 10 simulated cases of multiple trauma. RESULTS: An SOS effect could be demonstrated only in the second experiment. Analysis of dwell times showed that search on subsequent radiographs was shortened when the initial radiograph contained a fracture; however, the errors were not based on faulty scanning. CONCLUSION: The SOS effect in musculoskeletal trauma is not caused by faulty scanning. Demonstration of an SOS effect on test fractures with major but not minor additional fractures suggests that detection of other fractures is inversely related to the severity of the detected fracture.     

Spine fractures in falling accidents: analysis of multidetector CT findings

The purpose of the present study was to assess incidence, fracture type, and location of spine fractures due to falls. All emergency room CT requests during a time period of 26 months were reviewed retrospectively. Patients who had fallen or jumped and were initially examined with multidetector CT (MDCT) were included. The MDCT studies were evaluated by two radiologists for trauma location, fracture type, and multiple level involvement. A total of 237 patients (184 males, 53 female, age range 16–86 years, mean age 42 years) met the inclusion criteria. A total of 203 vertebral fractures were seen in 127 patients. Burst fracture (n=78) was the most frequent type of trauma, usually located in the thoracolumbar junction (50%). Also, compression fracture (n=52) was most common in the thoracolumbar junction (39%). Posterior column fracture (n=52) was most frequently detected in the cervical spine (40%). Multiple-level spine fractures were seen in 41 (32%) of the injured patients, of which 12 (29%) had fractures at noncontinuous levels. With increasing height the overall incidence of fractures increased, and burst fractures and multiple level spine fractures became more frequent. Age had no effect on fracture type or location. Spine fractures due to falls are common. Burst fracture is the most common fracture type and most frequently seen in the thoracolumbar junction. Multiple-level fractures were seen in 32% of the cases, of which 29% were seen at noncontinuous levels. Serious spine fractures are seen in all falling height and age groups.     

Radiographically occult femoral and pelvic fractures are not mutually exclusive: a review of fractures detected by MRI following low-energy trauma

Objectives

The purpose of this study was to review the MRI examinations of a large group of low-energy trauma patients in whom pelvic MRI had detected radiographically occult fractures, in order to characterize prevailing fracture patterns and determine how often co-existing proximal femoral and pelvic fractures were observed.

Methods

All patients having pelvic MRI over 5?years were identified. Word-search software selected 269 MRI reports containing the term ‘fracture’. Further scrutiny identified 168 with diagnosis of fracture. MRI request and imaging record review identified 102 low-energy trauma cases that had MRI for clinical suspicion of fracture despite normal radiographs. Sixty-six cases were excluded for the following reasons: no expressed clinical suspicion of occult fracture; history suggesting high-energy trauma; skeletal co-morbidity hindering acute fracture identification; interval more than 2?weeks between radiographs and MRI. The 102 study MRI examinations, which employed a limited two-sequence protocol, were reviewed. Any fracture that had not been appreciated on radiographs was recorded and characterized as femoral, pelvic, or co-existing femoral and pelvic fractures.

Results

The 102 study cases had a median age of 82?years. The median interval between pelvic radiographs and MRI was 3?days. MRI showed undiagnosed femoral fracture in 48/102 cases (47.1%), sacral fracture in 41/102 (40.2%), and pubic fracture in 55/102 (53.9%). In 11/102 cases (10.8%), MRI showed undiagnosed fractures of both proximal femur and pelvic ring (seven sacral, six pubic bone, two other site fractures). In 10/11 cases with co-existing femoral and pelvic fractures, the femoral fracture was incomplete.

Conclusions

Limited pelvic MRI found a high prevalence of radiographically occult femoral and pelvic fractures in low-energy trauma patients, with clinical suspicion of fracture despite normal radiographs. Co-existing occult femoral and pelvic ring fractures were commonly observed, and in such cases, the femoral fracture was likely to be incomplete and multiple pelvic fractures were typically present.     

Under-reporting of osteoporotic vertebral fractures on computed tomography

Purpose

Osteoporotic vertebral fractures are frequently asymptomatic. They are often not diagnosed clinically or radiologically. Despite this, prevalent osteoporotic vertebral fractures predict future osteoporotic fractures and are associated with increased mortality and morbidity. Appropriate management of osteoporosis can reduce future fracture risk. Fractures on lateral chest radiographs taken for other conditions are frequently overlooked by radiologists. Our aim was to assess the value of computed tomography (CT) in the diagnosis of vertebral fracture and identify the frequency with which significant fractures are missed.

Materials and methods

The thoracic CT scans of 100 consecutive male and 100 consecutive female patients over 55 years were reviewed. CT images were acquired on General Electric Lightspeed multi-detector (MD) CT scanners (16 or 32 row) using 1.25 mm slice thickness. Midline sagittal images were reconstructed from the 3D volume images. The presence of moderate (25–40% height loss) or severe (>40% height loss) vertebral fractures between T1 and L1 was determined using an established semi-quantitative method and confirmed by morphological measurement. Results were compared with the formal CT report.

Results

Scans of 192 patients were analysed (95 female; 97 male); mean age 70.1 years. Thirty-eight (19.8%) patients had one or more moderate to severe vertebral fractures. Only 5 (13%) were correctly reported as having osteoporotic fractures in the official report. The sensitivity of axial CT images to vertebral fracture was 0.35.

Conclusion

Incidental osteoporotic vertebral fractures are under-reported on CT. The sensitivity of axial images in detecting these fractures is poor. Sagittal reformations are strongly recommended to improve the detection rate.     

The contribution of high-resolution multiplanar reformats of the skull base to the detection of skull-base fractures

AIM: To investigate the contribution of routine review of submillimetric multiplanar reformats to the diagnosis of skull-base fractures. METHODS: A prospective analysis was performed of 407 cases referred over a 6-month period for CT of the skull following cranial trauma. The reformatted 5-mm axial sections and subsequently the high-resolution multiplanar reformats (HRMPRs) were viewed on an ADW 4.1 workstation using bone windows and algorithm. All skull-base fractures and related features, recorded by the consensus of two radiologists, were classified as anatomically significant or non-significant on the basis of eight criteria. The clinical features of skull-base injury and any subsequent treatment were noted in all cases of skull-base fracture. RESULTS: HRMPRs detected 80 separate skull-base fractures in 36/407 cases. Of these 80 fractures, 57 were visible on 5-mm axial sections. In 8 of the 36 cases, the significant anatomical features were only evident on review of the HRMPRs. In 6 of the 36 cases, none of the skull-base fractures was visible on 5-mm sections, but these individuals had only minor associated clinical features and no therapeutic requirements. Review of HRMPRs could have been confined to patients with skull-base fractures, abnormal intracranial and extracranial air collections or opacified mastoid air cells revealed by 5-mm axial sections. This policy would have led to the detection of 79/80 (99%) of skull-base fractures and all significant anatomical features. CONCLUSION: The 5-mm axial sections demonstrated 71% of skull-base fractures and 78% of skull-base fractures with significant anatomical features, using HRMPRs as a gold standard. There were no significant clinical sequelae at short-term follow-up of those fractures only evident on HRMPRs.     

Wrist injuries; diagnosis with multidetector CT

The aim of the study was to assess acute-phase multidetector CT (MDCT) findings in wrist injuries. We retrieved all emergency room MDCT requests processed in the period from August 2000 to May 2003. All patients with a wrist injury who underwent MDCT initially were included. Imaging studies were evaluated in relation to injury mechanism, fracture location, and fracture type. A total of 6422 MDCT examinations were performed during this 34-month period, and 38 patients (24 male, 14 female, age range 21–73 years, mean age 40 years) met the inclusion criteria. MDCT revealed 56 fractures and 7 dislocations in 29 patients. In 9 patients (24%) MDCT findings were normal. Eleven patients (29%) underwent surgical procedures. The main injury mechanism was a fall (58%). In 33 cases the primary radiograph was available. Compared to primary radiographs, MDCT revealed 9 occult fractures, mainly in small carpal bones. In 14 cases a suspected fracture (of the scaphoid in 7 cases) was ruled out by MDCT. Due to high-quality two-dimensional reformatting, MDCT examinations were not dependent on the wrists position in the CT gantry. In the comparison with radiography, MDCT detected occult fractures and ruled out suspected fractures, both mainly in the small carpal bones. High-quality two-dimensional reformats gave significant information about the fracture anatomy. MDCT provides fast and valuable information in assessing complex wrist fractures or when the primary radiograph is equivocal.     

Greater trochanteric fracture with occult intertrochanteric extension

Proximal femoral fractures are frequently encountered in the emergency department (ED). Prompt diagnosis is paramount as delay will exacerbate the already poor outcomes associated with these injuries. In cases where radiography is negative but clinical suspicion remains high, magnetic resonance imaging (MRI) is the study of choice as it has the capability to depict fractures which are occult on other imaging modalities. Awareness of a particular subset of proximal femoral fractures, namely greater trochanteric fractures, is vital for both radiologists and clinicians since it has been well documented that they invariably have an intertrochanteric component which may require surgical management. The detection of intertrochanteric or cervical extension of greater trochanteric fractures has been described utilizing MRI but is underestimated with both computed tomography (CT) and bone scan. Therefore, if MRI is unavailable or contraindicated, the diagnosis of an isolated greater trochanteric fracture should be met with caution. The importance of avoiding this potential pitfall is demonstrated in the following case of an elderly woman with hip pain and CT demonstrating an isolated greater trochanteric fracture who subsequently returned to the ED with a displaced intertrochanteric fracture.     

The advantages of MRI in the detection of occult hip fractures

While the displaced hip fracture can be visualized easily by plain radiography, the non-displaced fracture may be radiographically occult and require different imaging modalities, e.g., MRI for proper visualization. The accuracy of readers and cost advantages of utilizing MRI have not been assessed. Therefore, we undertook a study of these factors. The medical records of all patients who had visited the emergency room from June 2002 until May 2003 with a clinically suspected hip fracture, negative or equivocal plain film and subsequent MRI examination were retrospectively reviewed. Two senior and two junior radiologists independently evaluated both the MR images and radiographs of all 33 patients in a blinded study. One of three possible evaluations was described for the images of each modality: absence, presence or possibility of fracture. The economic consequences of using MRI in the detection of occult hip fractures were calculated. For all four doctors participating in this study, MRI proved to be far more sensitive and specific in the detection of occult hip fractures than radiography. Using the MR images, the senior radiologists identified the occult hip fracture patients with 100% accuracy and were in complete agreement. The agreement between junior and senior radiologists was high (average =0.75). MRI also detected soft tissue injuries in 39% of the patients that could not be identified with radiography. Adoption of the new protocol using MRI saves hospitals from €242 to 627 per patient. By shortening the time to diagnosis and permitting a superior visualization of both bone and soft tissue injuries, MR imaging prevents unnecessary hospitalization and delays in definitive treatment. MR images should be assessed by senior radiologists.     

Fractures easily missed by conventional radiographic diagnosis]

Although conventional radiography is the mainstay for diagnosing fractures, there are multiple conditions in which a fracture can be overlooked by the radiologist. This report focuses on the radiographic findings of various presentations of fractures including (1) minimally displaced fractures, (2) avulsion fractures, (3) stress fractures, (4) incomplete fractures and physeal injuries in children, and (5) occult fractures complicated with overt injury. Radiologists need to be familiar with these relatively common entities and aware of the limitations of radiography for fracture diagnosis; there are cases that can be diagnosed clinically without radiographic findings of cortical disruption. Repeated radiographic examination, CT, or MRI may be indicated depending on the clinical situation. The involvement of radiologists in the routine interpretation of conventional radiographs in trauma settings is encouraged to improve the detection of subtle fractures.     

Second metatarsal stress fracture in sport: comparative risk factors between proximal and non-proximal locations

Background

Stress fractures of the second metatarsal are common injuries in athletes and military recruits. There are two distinct areas in the second metatarsal where stress fractures develop: one proximal (at the base) and the other non‐proximal (distal). Diagnosis can be difficult, and there is a difference in prognosis and treatment of the two types of stress fracture. Therefore differentiation of fracture location is warranted. Differences in risk factors and clinical outcomes between proximal and non‐proximal stress fractures have not been studied.

Objective

To determine whether different risk factors and/or clinical outcomes associated with proximal and non‐proximal stress fractures of the second metatarsal exist.

Methods

Patients diagnosed with proximal stress fractures of the second metatarsal were included in the study. Retrospectively, an age‐matched control group with a non‐proximal stress fracture was selected for comparison. Statistical analysis involved bivariate comparisons of demographic variables and clinical measurement between the two groups.

Results

Patients with proximal stress fractures were more likely to be chronically affected, usually exhibited an Achilles contracture, showed differences in length of first compared with second metatarsal, were more likely to experience multiple stress fractures, and exhibited low bone mass. In addition, a high degree of training slightly increased the risk of a non‐proximal fracture, whereas low training volume was associated with a proximal stress fracture.

Conclusion

The signs, symptoms and clinical findings associated with proximal metatarsal stress fractures are different from those of non‐proximal stress fractures.     

Visual expertise in detecting and diagnosing skeletal fractures

Objective

Failure to identify fractures is the most common error in accident and emergency departments. Therefore, the current research aimed to understand more about the processes underlying perceptual expertise when interpreting skeletal radiographs.

Materials and methods

Thirty participants, consisting of ten novices, ten intermediates, and ten experts were presented with ten clinical cases of normal and abnormal skeletal radiographs of varying difficulty (obvious or subtle) while wearing eye tracking equipment.

Results

Experts were significantly more accurate, more confident, and faster in their diagnoses than intermediates or novices and this performance advantage was more pronounced for the subtle cases. Experts were also faster to fixate the site of the fracture and spent more relative time fixating the fracture than intermediates or novices and this was again most pronounced for subtle cases. Finally, a multiple linear regression analysis found that time to fixate the fracture was inversely related to diagnostic accuracy and explained 34 % of the variance in this variable.

Conclusions

The results suggest that the performance advantage of expert radiologists is underpinned by superior pattern recognition skills, as evidenced by a quicker time to first fixate the pathology, and less time spent searching the image.     

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

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

MRI as a reference standard for suspected scaphoid fractures

Objectives

Some have suggested that MRI might be the best reference standard for a true fracture among patients with suspected scaphoid fractures. The primary aim of this study was to determine the rate of false-positive diagnosis of an acute scaphoid fracture in a cohort of healthy volunteers.

Methods

In a prospective study, 33 healthy volunteers were recruited and both wrists of each were scanned, except for 2 volunteers for whom only one wrist was scanned. To simulate the usual clinical context the 64 scans of healthy volunteers were mixed with 60 MRI scans of clinically suspected scaphoid fractures but normal scaphoid radiographs. These 124 MRI scans were blinded and randomly ordered. Five radiologists evaluated the MRI scans independently for the presence or absence of a scaphoid fracture and other injuries according to a standard protocol.

Results

To answer the primary question, only the diagnoses from the 64 scans of healthy volunteers were used. The radiologists diagnosed a total of 13 scaphoid fractures; therefore, specificity for diagnosis of scaphoid fracture was 96% (95% confidence interval: range 94–98%). The 5 observers had a moderate interobserver agreement regarding diagnosis of scaphoid fracture in healthy volunteers (multirater κ=0.44; p<0.001).

Conclusions

The specificity of MRI for scaphoid fractures is high (96%), but false-positives do occur. Radiologists have only moderate agreement when interpreting MRI scans from healthy volunteers. MRI is not an adequate reference standard for true fractures among patients with suspected scaphoid fractures.The American College of Radiologists recommends MRI for diagnosis of true fractures among suspected scaphoid fractures [1]. A number of published studies cite sensitivities and specificities approaching 99% [2-9], but other studies have reported a lower sensitivity (80%) and substantial interobserver variation (κ=0.67) for diagnosis of a scaphoid fracture [2,8]. It has been difficult to agree upon a reliable reference standard for true fractures among suspected scaphoid fractures, and these studies often use only repeated radiographs 6 weeks after trauma as reference standard. However, it is also known that not all occult scaphoid fractures become apparent on repeated radiographs.It is not clear how to distinguish true fracture from other changes in bone signal that are detected with MRI. We propose that MRI of the wrists of healthy volunteers with no history of wrist or hand injury represents a reliable reference standard for the absence of an acute fracture of the scaphoid waist. By evaluating MRI scans of healthy volunteers, we may learn more about the diagnostic performance characteristics of MRI for suspected scaphoid fracture. A set of MRI scans with a reliable reference standard would also provide useful information about the reproducibility of the interpretation of MRI for suspected scaphoid fracture.The primary study question was to investigate the occurrence of false-positive diagnosis of an acute scaphoid fracture on MRI using a reliable reference standard (healthy volunteers). Secondarily we also investigated the interobserver variation of diagnosis of scaphoid fracture on MRI in healthy volunteers.     

Percutaneous osteosynthesis in the pelvis in cancer patients

Purpose

Screw fixation (osteosynthesis) can be performed percutaneously by interventional radiologists. We report our experience in cancer patients.

Material/methods

We retrospectively reviewed all cases of percutaneous osteosynthesis (PO) of the pelvic ring and proximal femur performed in our hospital. PO were performed for fracture palliation or for osteolytic metastases consolidation. Screws were inserted under CT- or cone-beam CT- guidance and general anaesthesia. Patients were followed-up with pelvic-CT and medical consultation at 1 month, then every 3 months. For fractures, the goal was pain palliation and for osteolytic metastases, pathologic fracture prevention.

Results

Between February 2010 and August 2014, 64 cancer patients were treated with PO. Twenty-one patients had PO alone for 33 painful fractures (13 bone-insufficiency, 20 pathologic fractures). The pain was significantly improved at 1 month (VAS score?=?20/100 vs. 80/100). In addition, 43 cancer patients were preventively consolidated using PO plus cementoplasty for 45 impending pathologic fractures (10 iliac crests, 35 proximal femurs). For the iliac crests, no fracture occurred (median-FU?=?75 days). For the proximal femurs, 2 pathological fractures occurred (fracture rate?=?5.7 %, median-FU?=?205 days).

Conclusion

PO is a new tool in the therapeutic arsenal of interventional radiologists for bone pain management.

Key Points

? Screw fixation (osteosynthesis) can be performed percutaneously by interventional radiologists. ? CT- or CBCT-guidance results in high technical success rates for screw placement. ? This minimally invasive technique avoids extensive surgical exposure in bone cancer patients. ? Osteosynthesis provides pain relief for bone-insufficiency fractures and for pathologic fractures. ? Osteosynthesis plus cementoplasty provide prophylactic consolidation of impending pathological fractures.

     

Acute paediatric ankle trauma: MRI versus plain radiography

OBJECTIVE: To evaluate the diagnosis of acute physeal ankle fractures on plain radiographs using MRI as the gold standard. METHODS: Sixty consecutive children, 29 with a clinical diagnosis of lateral ligament injury and 31 with physeal ankle fractures, were examined using both radiographs and MRI in the acute period. The imaging data were reviewed by three "masked" radiologists. The fracture diagnosis and Slater-Harris classification of radiographs were compared with findings on MRI. RESULTS: Plain radiography produced five of 28 (18%) false negative and 12 of 92 (13%) false positive fracture diagnoses compared with MRI. Six of the 12 false positive fractures were due to a misclassification of lateral ligament disruption as SH1 fractures, Altogether a difference was found in 21% of cases in either the diagnosis or the classification of the fractures according to Salter-Harris. All bone bruises in the distal tibia and fibula and 64% of bone bruises in the talus were seen in association with lateral ligament injuries. Talar bone bruises in association with fractures occurred on the same side as the malleolar fracture; talar bone bruises in association with lateral ligament disruption were seen in different locations. The errors identified on radiographs by MRI did not affect the management of the injury. CONCLUSIONS: The incidence of false negative ankle fractures in plain radiographs was small and no complex ankle fractures were missed on radiographs. The total extent of complex fractures was, however, not always obvious on radiographs. In an unselected series of relatively mild ankle injuries, we were unable to show a single case where the treatment or prognosis based on plain radiography should have been significantly altered after having done a routine MRI examination. Plain radiography is still the diagnostic cornerstone of paediatric ankle injuries.     

Isolated Tympanic Plate Fracture Frequency and Its Relationship to Mandibular Trauma

Purpose

This study evaluated the prevalence of isolated tympanic fractures and their correlation with mandibular fractures by using maxillofacial computed tomography (CT).

Materials and Methods

We retrospectively evaluated the maxillofacial CT of 1590 patients who presented to our emergency department with maxillofacial trauma between December 2010 and December 2012. Maxillofacial CT was used as the criterion standard for evaluating patients with maxillofacial fractures. The CT images were evaluated by using an electronic picture archiving and communications system and interpreted independently by 2 radiologists.

Results

The maxillofacial CT images revealed mandibular fractures in 167 of the patients and isolated tympanic plate fractures in 35 of these 167 patients. Four patients (11%) had a bilateral tympanic plate fracture, and 31 patients (89%) had unilateral tympanic plate fracture. Of all the tympanic plate fractures, 19 (54%) were on the right side and 16 (46%) were on the left side (P > .05). In our results, a significant correlation between the presence of a right-sided tympanic plate fracture and fracture of the ipsilateral condylar process was found (P = .036). However, a statistically significant difference between the presence of a tympanic plate fracture and other mandible fractures, additional soft-tissue findings, or the number of fractures was not determined (P > .05). Sex had no impact on the presence of tympanic plate fracture (P > .05).

Conclusion

The frequency of isolated tympanic plate fractures in maxillofacial trauma is low, but it is an important anatomic location. Condyle fractures are significantly associated with isolated tympanic plate fractures. The presence of these injuries should raise suspicion of a concomitant isolated tympanic plate fracture.     

Who is more accurate in the diagnosis of neck of femur fractures, radiologists or orthopaedic trainees?

Objective

Our study aims to compare the sensitivity and specificity between orthopaedic trainees and radiologists in diagnosing occult hip fractures from pelvic radiographs.

Methods

All patients undergoing computed tomography (CT) of the hip for a suspected occult hip fracture at our two centres between November 1, 2010 and October 31, 2011 were retrospectively identified. Two orthopaedic trainees (RJ and ED) independently reviewed the initial radiographs, and if both agreed a fracture was present this was recorded. The reports from the radiologist of the initial radiograph and subsequent CT were recorded, with the CT report used as the standard of reference for comparison of performance.

Results

239 CTs were performed for suspected neck of femur fractures during the study period, compared to only 20 in 2006–07, reflecting a 1,095 % increase. The interpretation of radiographs by the orthopaedic trainees showed a sensitivity of 55.4 % and specificity of 96.6 %. In comparison, the radiologists had a sensitivity of 60.7 % and specificity of 92.9 %; this difference was shown not to be statistically significant. Radiologists and orthopaedic trainees agreed when interpreting the majority of radiographs with a Kappa co-efficient of 0.77 (a statistical measure of inter-rater agreement). In 20 of the 174 cases (11.5 %) where the radiologist and orthopaedic trainees agreed no fracture was present, the subsequent CT revealed a fracture.

Conclusion

Orthopaedic trainees and radiologists have similar accuracy at interpreting pelvic radiographs for suspected hip fractures, so the trainee’s opinion can be relied upon. If uncertainty exists, then either the orthopaedic trainee or radiologist should request further imaging urgently as we believe this will expedite diagnosis and treatment of hip fractures, and ensure judicious use of CT.     

Imaging of stress fractures in the athlete

Osseous stress fractures and stress reactions represent the effect of abnormal repetitive stress on normal bone. An accurate and thorough clinical history and sequential radiographs often suffice 40 make the diagnosis especially when the fracture occurs in one of the common locations, such as the tibia, metatarsals, or calcaneus. In cases that are atypical in location or clinical presentation the authors rely more on MR imaging, radionuclide bone scanning, and occasionally CT. MR imaging detects early changes of osseous stress injury and allows precise definition of anatomy and extent of injury, and is the preferred modality for evaluating the continuum of osseous manifestations of stress injury. MR imaging is useful in evaluating shin splints, early osseous stress injuries, and overt stress fracture. In the elite athlete prompt diagnosis and early rehabilitation are the goals.