Routine pelvic X-rays in asymptomatic hemodynamically stable blunt trauma patients: A meta-analysis

Accepted Manuscript Title: Routine Pelvic X-rays in Asymptomatic Hemodynamically Stable Blunt Trauma Patients: a Meta-Analysis Authors: Jessica van Trigt, Niels Schep, Rolf Peters, Carel Goslings, Tim Schepers, Jens Halm PII: DOI: Reference:

S0020-1383(18)30490-X https://doi.org/10.1016/j.injury.2018.09.009 JINJ 7816

To appear in:

Injury, Int. J. Care Injured

Accepted date:

5-9-2018

Please cite this article as: van Trigt J, Schep N, Peters R, Goslings C, Schepers T, Halm J, Routine Pelvic X-rays in Asymptomatic Hemodynamically Stable Blunt Trauma Patients: a Meta-Analysis, Injury (2018), https://doi.org/10.1016/j.injury.2018.09.009 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Routine Pelvic X-rays in Asymptomatic Hemodynamically Stable Blunt Trauma Patients: a Meta-Analysis Jessica van Trigt1, Niels Schep2, Rolf Peters1, Carel Goslings3, Tim Schepers1, Jens Halm1

Unit, Department of Surgery, Amsterdam UMC, location AMC, Amsterdam,

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1Trauma

the Netherlands

3Department

of Surgery, Maasstad Hospital, Rotterdam, the Netherlands

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2Department

of General and Trauma Surgery, Onze Lieve Vrouwe Gasthuis,

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Amsterdam, the Netherlands

Meibergdreef 9

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Amsterdam UMC

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JA Halm, MD, PhD

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Corresponding author

1105AZ Amsterdam

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The Netherlands

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[email protected]

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+31-(0)20-66065

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Abstract Introduction There is no consensus on how pelvic X-rays should be ordered selectively in blunt trauma patients which may save time, reduce radiation exposure and costs. The aim of this systematic review and meta-analysis was to assess the need for routine pelvic X-rays in awake, respiratory and hemodynamically (HD) stable blunt trauma patients without signs of pelvic fracture. Criteria to identify patients who could safely forgo pelvic X-ray were evaluated. Methods A literature search was performed for prospective comparative cohort studies. Inclusion criteria were: blunt force trauma, hemodynamically and respiratory stable and awake patients, physical examination (PE) for pelvic fractures was adequately described, and the reliability of negative PE findings could be evaluated. Primary outcome was the negative predictive value (NPV) of PE for all and for clinically relevant pelvic fractures. Additionally sensitivity, specificity and positive predictive value (PPV) were calculated. Results Ten studies were included; yielding a total of 11,423 patients. The NPV of PE for all pelvic fractures ranged from 0.96 to 1.00 with a median of 0.996. Combining studies, total NPV was 0.991. For clinically relevant fractures, the NPV of PE ranged from 0.996 to 1.00 with a median of 1.00. In patients with negative findings during PE, 0.9% had fractures, and 0.1% had clinically relevant fractures, none requiring surgical management.

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Keywords: trauma, pelvis, blunt, imaging, physical examination

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Introduction Current Advanced Trauma Life Support (ATLS®) guidelines recommend routine pelvic X-rays as screening tools for severely injured blunt trauma patients1 . The manual also suggests that alert and awake patients without pelvic pain or tenderness do not require a pelvic radiograph1. Pelvic X-ray examination however is frequently part of a protocol

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driven assessment in all blunt trauma patients, without differentiation in injury severity.

Consequently, this may lead to overuse of radiographic examinations, especially in

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patients without obvious injuries or in monotrauma patients, including awake, hemodynamically and respiratory stable patients without signs of pelvic fracture.

Recent studies suggested that in certain patients (pelvic) X-rays may be ordered as

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targeted tests instead of being performed routinely2,3 . However, as opposed to the

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generally accepted national emergency x-radiography utilization study (NEXUS)

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criteria and the Ottawa ankle and knee rules, which limit unnecessary radiological

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pelvic X-rays in trauma patients.

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imaging in trauma patients4,5, no such consensus exists for avoiding unnecessary

Furthermore, a retrospective study found that most avoidable costs made during standard trauma work up were due to radiology and laboratory panels 3. Selective

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radiographic ordering might save time, reduce radiation exposure, and reduce costs.

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This systematic review and meta-analysis assessed the need for routine pelvic X-rays in awake, hemodynamically and respiratory stable blunt trauma patients without

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complaints, as suggested in the ATLS manual. In addition, criteria to identify these patients who could safely forgo pelvic X-rays were evaluated. Secondary objectives were to identify missed fractures and their clinical relevance, and to assess the influence of intoxication on the reliability of physical examination (PE) results. A decision instrument was proposed focusing on reduction of pelvic x-rays.

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Materials and Methods The present study was reported according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines (http://www.prismastatement.org/). Two authors independently conducted a search of the Cochrane

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Library, PubMed, EMBASE and GoogleScholar. The complete search strategy is

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depicted in Figure 1. No other resources were searched.

Selection of studies

Two reviewers independently reviewed all titles and abstracts for relevance. If title and

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abstract did not provide sufficient information, full text was examined. There were no

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language or date restrictions. The current study was limited to prospective comparative

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cohort studies only. Retrospective research, meta-analyses, review articles and

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articles not available in full text were excluded from this study. Also excluded were

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articles without a description of PE, those in which the study included only unconscious patients and studies of CT scan for trauma. Prospective comparative cohort studies were included if they met the following criteria:

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1. The mechanism of trauma was blunt force trauma.

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2. The patient population included patients considered to be hemodynamically and respiratory stable.

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3. The patient population included patients described as alert or awake. Glasgow Coma Scale (GCS) was allowed to vary. 4. The patients were examined for pelvic fractures (more extensive than pelvic stability evaluation only). 5. The PE for pelvic fractures was adequately described.

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6. The reliability of negative findings on PE was evaluated or could be evaluated using the study data.

Assessment of methodological quality and reporting bias For the assessment of methodological quality and the risk of bias, two reviewers

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assessed the included studies independently and findings were entered into RevMan version 5.3 (Review Manager (RevMan) [Computer program] Version 5.3.

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Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration; 2014).

Data extraction and management

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Two reviewers independently extracted data from eligible studies using a data

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collection form. Items extracted were: study setting, physician(s) who performed PE,

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trauma mechanism, hemodynamic and respiratory status, patients' GCS score,

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method of the PE, true positive (TP), false positive (FP), false negative (FN) and true

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negative (TN) findings using PE for identifying pelvic fractures, patients with missed fractures and their clinical relevance, and intoxication status. The primary outcome was the NPV of PE on (clinically relevant) pelvic fractures. Clinical relevant fractures were

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defined as fractures that led to a change in management. Sensitivity, specificity and

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PPV of PE on diagnosing pelvic fractures were also calculated. Secondary outcomes were missed fractures by PE and their clinical relevance, and the influence of

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intoxication on the reliability of the PE results.

Statistical analysis and data synthesis Sensitivity, specificity, PPV and NPV of PE for diagnosing pelvic fractures were calculated using TP, FP, FN and TN findings whenever possible. Findings were

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entered into RevMan version 5.3 for calculation using a single test analysis and a 95% confidence interval for estimates of sensitivity and specificity.

Results Results of the search

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No Cochrane reviews or randomized controlled trails were found regarding routine pelvic radiography in blunt trauma patients. PubMed, EMBASE, and GoogleScholar

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yielded a total of 31 relevant articles regarding the role of routine pelvic radiography in

blunt trauma patients. A total of 10 prospective-comparative cohort studies that met

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Methodological quality and reporting bias

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our inclusion criteria remained (Figure 1).

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reviewers is shown in Figure 2.

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An overview of the methodological quality of the included studies as assessed by the

Study characteristics

An overview of the study demographics of the included studies is given in Table 1. The

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10 studies included a total of 11,559 patients. Age ranged between 31.5 to 39.8 years,

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however one study 6 did not mention the average patient age. Three of the ten studies did not use age as an inclusion criterion 7-9. For the purpose of this review, patients in 8

grouped into the unconscious (GCS≤8) or impaired

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the study by Civil et al.

(8
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analyzed

various routine tests. The current meta-analysis excluded the patients for which Koksal et al.2 did not analyze the routine use of pelvic X-ray (n=4). A total study population of 11.423 patients remained. Holmes et al. 10 tested 2 different clinical decision rules. For

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the purpose of this review, data from the clinical decision rule consisting of the following variables was used: hypotension, GCS<14, pelvic bone instability, pelvic bone tenderness and distracting painful injury.

Setting and examining physicians

2,7,9,14.

or University Hospitals

Physicians performing the PE were trauma or emergency medicine residents

residents or attending physicians 6,10, and attending physicians 7,8,12. Three studies

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2,11,

6,7 9-13

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All studies were performed in Level 1 trauma centers

did not report on the type of physicians performing the PE

In case of doubt,

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Yugueros et al. 14 consulted an orthopedic surgeon.

9,13,14.

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Trauma mechanism

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In 6 of the 10 studies, motor vehicle collision was the most common trauma

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mechanism, ranging in occurrence from 51.5 to 83 percent (median 65.4%) 2 9-13. One study 14 mentioned pedestrian and motorcycle collision as the most common trauma mechanism (no percentage was given), and 3 studies

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did not report further data

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regarding the mechanism of trauma. None of the studies reported on the relation

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between trauma mechanism and missed fractures in patients with negative PE findings. Holmes et al.

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found that pelvic fractures were most prevalent in crush

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injuries to the torso (24.5%) and Civil et al.

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reported that all pelvic fractures in alert

and awake symptomatic patients were due to motor vehicle accidents.

Hemodynamic and respiratory status

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All studies evaluated forgoing pelvic X-ray in patients who were awake and could be evaluated clinically through physical examination. The PE went beyond mere testing for pelvic instability and required reliable patient responses. And although no studies explicitly reported on respiratory status, for extensive PE for pelvic fractures a stable patient status is presumed. Two of the ten studies only included hemodynamically (HD) 12,14.

HD stability was defined by Paydar et al.

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as a systolic blood

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stable patients

pressure (SBP) of >90 mmHg, and a heart rate of <100 beats per minute (bpm). 14

however, did not further define “hemodynamically stable”. In one

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Yugueros et al.

study, a SBP <90 mmHg was part of the high-risk variables used in deciding to obtain pelvic radiography before computed tomography (CT) 10. Seven studies did not report

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on, or draw conclusions based on, HD stability 2 11,13 6-9 However, Barleben et al. 7 did

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Glasgow Coma Scale (GCS)

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mention that patients forgoing pelvic X-ray should always be HD stable.

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Five of the ten articles used GCS as a criterion for patient inclusion 2 11-14. One article only included patients with a GCS of 15, two articles 11,12 with a GCS ≥14, one article

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with a GCS ≥13, and one article

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with a GCS ≥10. In the five remaining studies,

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patients were included regardless of their GCS 6-10. However, in four of these studies 6,10,

or

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PE was considered to be reliable in patients with a GCS of 15 8, a GCS of ≥14

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a GCS of ≥13 9. One study reports no GCS in their methods or results 7.

Physical examination The total number of patients with negative findings during PE was 8.082, which corresponds to 70.8% of the examined blunt force trauma patients (median 87.3%,

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range 44.8-100). The total number of patients with positive findings during PE was 3341, which corresponds to 29.2% of the examined blunt force trauma patients (median 13.8%, range 4.0-55.2). Of the patients with positive findings during PE, 82.3% were false positive (median 65.1%, range 32.1-88.8). None of the studies used the same criteria during PE. All methods of PE were reviewed and categorized into 10

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groups: 1) HD stability, 2) bleeding, hematoma and/or swelling of the pelvic area during inspection (included blood at the urethral meatus, gross hematuria, ecchymosis,

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swelling or abrasions of the pelvic area, lumbosacral or genital area), 3) deformities or signs of hip dislocation during inspection, 4) patient complaints of pelvic and/or hip

pain, 5) paresthesia or neuropathy of the groin and/or lower extremities, 6) tenderness

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during palpation of the pelvis (included palpation of pelvic girdle, pubic symphysis, iliac

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spines, inward and/or posterior iliac compression), lower back or sacrum, 7) pelvic

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instability during PE (included instability to lateral and medial compression on the iliac

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crests and rocking of the pelvis), 8) pain during hip flexion or rotation, 9) abnormalities

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in rectal examination, and 10) signs of intoxication or distracting injury. An overview of the PE performed per study is given in Table 2. Important to note is that 2 studies only included hemodynamically stable patients 12,14, one study excluded intoxicated patients and one study excluded patients with spinal injury

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2,

14.

No study makes mention of

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analgesic use prior to or after PE.

Sensitivity, specificity and positive predictive value (PPV) True positive (TP), false positives (FP), false negative (FN) and true negative (TN) findings, sensitivity and specificity of PE for all pelvic fractures are shown in Figure 3.

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Because Paydar et al. 12 excluded any patients with positive findings during PE, no TP and FP could be determined. Also, Duane et al. 9 did not perform any further imaging in patients with negative findings during PE, so FN and TN could not be calculated. As a result, the sensitivity and specificity for the aforementioned studies could not be calculated. Sensitivity (95% CI) ranged from 0.37 (0.25-0.51) to 1.00 (0.92-1.00) with

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a median of 0.94. Specificity (95% CI) ranged from 0.48 (0.44-0.51) to 0.98 (0.93-1.00) with a median of 0.94. Calculated sensitivity (95% CI) and specificity (95% CI) out of

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the total number of TP, FP, FN and FP, were 0.89 (0.86-0.91) and 0.74 (0.73-0.74) respectively. Excluding data by Duane et al. 9 and Paydar et al. 12, sensitivity (95% CI) was 0.89 (0.86-0.91), and specificity (95% CI) was 0.74 (0.73-0.74). PPV ranged from

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0.112 to 0.679 with a median of 0.349. PPV of pooled data was 0.178 for all studies

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combined and 0.173 excluding the studies by Duane et al. 9 and Paydar et al. 12 (Table

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Negative Predictive Value (NPV)

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3).

An overview of the NPV per included study is given in Table 3. The NPV for all pelvic fractures ranged from 0.96 to 1.00 with a median of 0.996. For clinically relevant

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fractures the NPV ranged from 0.996 to 1.00 with a median of 1.00. The NPV could

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not be calculated for Duane et al. 9 due to the fact that asymptomatic patients did not receive pelvic X-ray (or any other type of imaging), so TN and FN could not be verified.

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However, patients without complaints for the remainder of their hospital stay (precise duration was not reported) were considered not to have clinically relevant fractures. All patients with negative findings on PE stayed asymptomatic for the remainder of their hospital stay, NPV for clinically relevant fractures was considered to be 1.00. The NPV for clinically relevant fractures could not be calculated for Koksal et al. 2 and Paydar et

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al.

12,

because these studies did not report on the clinical relevance of the missed

fractures. Total NPV for all fractures was 0.991, excluding data from Duane et al. 9 and Paydar et al. 12 the NPV for all fractures remained 0.991.

Patients with missed fractures and their clinical relevance

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Out of the 8,082 patients with negative findings on PE, a total of 70 (0.9%) patients

had a pelvic fracture (Table 4). This was excluding Duane et al. 9, for which missed

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fractures could not be verified. The number of patients with missed fractures per study

ranged from 0 to 37 fractures (median 2.5). This was 0.4% (median) of the total patient population ranging from 0 to 4.0%. One study had no fractures missed by PE 8.

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Two studies did not report on the clinical relevance of missed fractures

2,12.

The

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remaining eight studies, representing a total of 7.598 patients with negative findings

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on PE, did report on the clinical relevance of missed fractures 6-11 13,14. Out of these

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eight studies, a total of 66 (0.9%) patients with fractures, were missed by PE. A total

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of 8 patients, representing 12% of patients with missed fractures and 0.1% of the patients with a negative PE, required a change in management. These changes in management required no operations. Gonzalez et al. 11 reported that of the 7 patients

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with missed fractures, 2 patients required a “non-weight bearing”, and 5 patients 6

reported that of

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required a “weight bearing as tolerated” management. Gross et al.

the 2 patients with missed fractures, 1 required a “non-weight bearing” management.

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In the other patients with missed fractures, there was no change in management.

Intoxication Four of the ten studies did not mention intoxication

7,10,12,14.

One study excluded all

patients who were intoxicated but failed to mention what criteria for intoxication were

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used 2. The remaining five articles assessed all included patients for intoxication either clinically 6,8, by blood alcohol level 8,9,11,13, and/or by toxicology screening

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None of

the articles reported an independent correlation between intoxication and reliability of the PE. No mention is made of analgesic use in the included studies.

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Proposed decision instrument

As advocated in various studies, forgoing routine pelvic X-ray should only be

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considered in hemodynamically stable patients 7,10,12,14. This implies that patients considered for selective pelvic X-ray should be stable. Nine of the ten studies

analyzed in the current review based their conclusions on either awake/alert patients

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or used a GCS cut off value for PE to be considered reliable 2,6,8-14. All studies with a

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NPV >0.995 depended on PE if there was a GCS of ≥13

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≥14 11,12 or 15 8. For the

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purpose of the proposed decision instrument a GCS cut off value of ≥13 was

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recommended. Also, as suggested by Barleben et al. 7, pelvic radiography should not

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be omitted in patients going directly to the operating room. Furthermore, because of the fact that complaining of pelvic pain was considered as a sign of possible pelvic fracture 6,8,11,13, it was essential that communication was possible. Because the NPV

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tended to increase with the number of criteria used, seven criteria that were present

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in two or more of the four studies with a NPV >99.5% were used (divided into history, inspection and testing). In using the decision making instrument one is reminded that

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analgesics administered prior to PE may mask pelvic tenderness. Considering a recent study found that digital rectal examination was not useful as a

screening tool in trauma patients 15, this examination was excluded from the decision instrument. Finally, because in some studies pelvic X-ray fails to identify all clinically relevant fractures in symptomatic patients

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computed tomography (CT) could be

considered as an alternative in hemodynamically and respiratory stable patients with a GCS ≥13 and positive findings during PE. Additionally a CT may be especially considered in patients with a GCS<13. The proposed decision instrument is given in Figure 4.

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Discussion

This systematic review and meta-analysis suggests that in asymptomatic, awake,

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hemodynamically and respiratory stable trauma patients a normal PE almost certainly excludes the possibility of serious injury. Of all evaluated blunt trauma patients, 70.8% had negative PE findings. Total sensitivity and specificity of PE for all pelvic fractures

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were 0.89 (95% CI 0.87-0.92) and 0.74 (95% CI 0.73-0.74), respectively. PE for

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identifying all pelvic fractures had a combined NPV of 0.991. The NPV of PE for

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clinically relevant fractures had a median of 1.00 ranging from 0.996 to 1.00. Of the

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patients with negative PE findings, 0.9% had missed fractures. Only 0.1% of patients

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with negative PE findings had clinically relevant fractures, none of which required surgical intervention.

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One of the limitations of this meta-analysis was pooling data from 10 different studies.

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Although all included studies had a low or unclear risk of bias and met our inclusion criteria, they did not represent a completely homogenous group of patients. This was,

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among other things, a result of the difference in included patients resulting among others in heterogeneous blunt force trauma mechanisms. While three of the ten studies did not use age as an inclusion criterion 7-9, others used an age minimum of >17 6,10,12, >14 2,11, >13 14 or >12 years 13. Also, HD stability was an inclusion criterion for 2 studies 12,14,

while 7 other studies did not report on or draw conclusions on HD stability.

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However, the mean patient age in the studies differed little, ranging from 31.5 to 39.8 years. And, as advocated in various included studies

7,10,12,14,

patients considered to

forgo routine pelvic radiography should be hemodynamically stable. As suggested in the ATLS guidelines 1, hemodynamic stability was a prerequisite for considering

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selective pelvic X-ray in blunt trauma patients.

Another limitation was the differences in sensitivity and specificity of PE for all pelvic

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fractures among the included studies. First of all, sensitivity and specificity could not

be calculated for the studies by Duane et al. 9 and Paydar et al. 12 due to insufficient data. 2

were the only studies with sensitivity <

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Secondly Barleben et al. 7 and Koksal et al.

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0.90. This may be because Barleben et al. 7 used a decision instrument (for pelvic X-

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ray before CT), in which PE for pelvic fractures was limited to patient complaints of

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severe pelvic pain. Other PE’s were based on hemodynamic criteria and signs of femur

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fracture or hip dislocation. Koksal et al. 2 also only used PE for pelvic fractures, which was limited to severe pelvic pain during PE. The other criteria used were signs of intoxication and signs of femur fracture or hip dislocation. Also, Koksal et al.

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only

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included 99 patients for evaluation of pelvic fracture. Expanding their PE for pelvic

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fractures and including more patients would probably have led to a higher sensitivity of PE for pelvic fractures in these studies. Then again, Barleben et al. 7 included femur

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fractures as a positive finding for pelvic fractures, which could have led to a higher sensitivity than calculations with pelvic fractures alone. Thirdly, Gross et al. 6 and Holmes et al. 10 had a specificity of 0.48 (95% CI 0.44-0.51) and 0.58 (95% CI 0.56-0.59) respectively. All other studies had a specificity of 0.88 or higher. This might be explained by the fact that in the study by Gross et al. 6 there was

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biased enrolment in which not all patients underwent standard pelvic X-ray (due to, among other things, cost concerns). For these patients, excluded by Gross et al. 6, physicians did not find it necessary to order pelvic X-ray, probably due to low probability of pelvic fracture. Including these patients could have led to more true negatives and/or less false positives, leading to a higher specificity. Holmes et al. 10 used their decision

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instrument for identifying patients required to undergo pelvic X-ray before CT. This

required a high sensitivity using a number of high-risk clinical variables, limiting the PE

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for pelvic fractures to pelvic bone instability and/or pelvic bone tenderness on

palpation. Expanding PE of the pelvis and including patients who were not planned to undergo CT could have led to a higher number of true positives and thus, to a higher

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specificity.

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The GCS considered for a reliable PE ranged from ≥10 to 15. Eight of the ten studies

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hypothesized reliable PE results for GCS's of ≥13 9,13, ≥14 6,10-13, or 15 2,8. Also, a GCS

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of 13, 14 or 15 is one of the criteria in diagnosing "minor head injury"18. And, although Yugueros et al. 14 included patients with a GCS of ≥10, 74.3% of the included patients had a GCS of 15, 23.8% a GCS between 11 and 14 and only 1.8% a GCS of 10. Also,

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they suggested selective use of pelvic X-ray only on awake patients. In the study by

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Holmes et al. 10, using different GCS cut-off values of 15 and ≥14 resulted in an equal

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NPV (0.991).

PE criteria and the examining physician also varied per study. However, the following eight criteria were present in two or more of the four studies with a NPV >0.995: tenderness to palpation of the pelvis (described as palpation of pelvic girdle 9, pubic symphysis 8,10-13, iliac spines 8,10,12,13, inward and/or posterior iliac compression

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11,12),

lower back or sacrum, bleeding or swelling of the pelvic area, patient complaints of pelvic or hip pain, pelvic instability, pain during hip flexion or rotation, deformities or signs of hip dislocation, paresthesia of neuropathy of the groin or lower extremities, and gross blood or high riding prostate upon rectal examination. However, a recent study did not advocate digital rectal examination as a screening tool in trauma patients Hemodynamic stability and intoxication and/or distracting injury were the only

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criteria of PE performed that were not included in the abovementioned list. However,

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physical examination went beyond testing for pelvic instability in all studies and required reliable patient responses. Distracting injury was only part of the PE criteria in 2 studies

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as a part of the decision making instrument. Which injuries were

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considered distracting however was not defined. Generally speaking a distracting

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injury is defined as a painful injury that distracts patients from reporting pain in a critical

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area (e.g. cervical spine). This phenomenon has been studied extensively confirming

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source of potential error.

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its importance when relying on physical examination 16-18 and should be considered a

Because this systematic review and meta-analysis aims to identify patients who could

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safely forgo pelvic X-ray, any proposed decision instrument must have a high NPV.

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The goal was not to diagnose pelvic fractures using only PE, but rather to minimize superfluous imaging. Diagnostic testing is judged by sensitivity and specificity, which

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in the case of PE in this review had a median of 0.94 (range 0.37-1.00) and 0.94 (range 0.48-0.98), respectively. However, CT imaging is more precise and regarded as the golden standard for diagnosing pelvic fractures in blunt trauma patients 19. The median for the NPV of PE for clinically relevant pelvic fractures was 1.00 (range 0.996-1.00). Hence almost all patients with negative findings on PE did not have a clinically relevant

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pelvic fracture. However, the study by Paydar et al.

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only included patients with

negative PE findings. In reality, a higher prevalence of pelvic fractures could be expected, which may have resulted in a lower NPV. Nevertheless, the narrow range of the NPV (0.996-1.00) found serves as indication for an overall high NPV for clinically relevant pelvic fractures. Only 8 (0.1%) patients with negative PE findings required a

required "weight bearing as tolerated" management change 6,11. 20

concluded that clinical evaluation for pelvic

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A retrospective study by Tien et al.

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change in management. Three patients required a "non-weight bearing" and 5 patients

fractures in patients with a GCS ≥13 was not influenced by intoxication (ethanol 100mg/dL or greater). In our study, none of the studies that analyzed for intoxication

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6,8,9,11,13.

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found that unconscious or intoxicated patients might have a

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although Civil et al.

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mentioned that the results of the PE were compromised by intoxication

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significant risk of pelvic fracture that could be missed by PE, no conclusions were

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drawn solely based on the state of intoxication. Furthermore, Gonzalez et al. 11 found

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a higher sensitivity for the intoxicated subgroup than for the overall patient population. This suggested that it is indeed the state of consciousness, and not the state of intoxication, which determined ability to report pain. Unfortunately the use of

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analgesics was not adequately covered in the included studies but should remain a

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serious caveat when relying on PE as diagnostic tool. Also, it is worth mentioning that in some studies pelvic X-ray failed to identify all clinically relevant fractures in

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symptomatic patients 10,11. CT scan should be considered as a reliable alternative for hemodynamically stable patients with a GCS ≥13 and positive findings on PE and be especially considered in patients with GCS<13 regardless of PE findings. The findings of this meta-analysis suggest that using specific criteria, blunt trauma patients who do not have serious pelvic injuries can be identified reliably by PE.

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Conclusions More than 70% of examined patients had negative findings on PE. In a very large number of patients there are no serious pelvic injuries to be found when PE is normal. This may well suggest that in awake, stable blunt trauma patients, PE could identify

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those patients who could safely forgo pelvic X-ray. Selective ordering of pelvic X-ray could lead to a decrease in patient work-up time, lower radiation exposure, and lower

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costs. A decision instrument was proposed aiming on reduction of pelvic x-ray keeping

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in mind to err on the side of caution (e.g. in the presence of distracting injuries).

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Compliance with Ethical Standards Disclosure of potential conflicts of interest Jessica van Trigt declares that she has no conflict of interest Niels Schep declares that he has no conflict of interest

Carel Goslings declares that he has no conflict of interest Tim Schepers declares that he has no conflict of interest

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Jens Halm declares that he has no conflict of interest

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Rolf Peters declares that he has no conflict of interest

Research involving Human Participants and / or Animals

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Meta-analysis of literature, informed consent not applicable

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Informed consent

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Meta-analysis of literature, informed consent not applicable

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Reference 1.

Advanced trauma life support (ATLS®): The ninth edition. Journal of Trauma

and Acute Care Surgery 2013;74:1363-6. 2.

Koksal O, Cevik SE, Aydin SA, Ozdemir F. Analysis of the necessity of routine

tests in trauma patients in the emergency department. Turkish Journal of Trauma and Emergency Surgery 2012;18:23-30. Tasse JL, Janzen ML, Ahmed NA, Chung RS. Screening Laboratory and

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3.

Radiology Panels for Trauma Patients Have Low Utility and Are Not Cost Effective. The Journal of Trauma: Injury, Infection, and Critical Care 2008;65:1114-6.

Appelboam A, Reuben AD, Benger JR, et al. Elbow extension test to rule out

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4.

elbow fracture: multicentre, prospective validation and observational study of diagnostic accuracy in adults and children. BMJ 2008;337:a2428-a. 5.

Morrison J, Jeanmonod R. Imaging in the NEXUS-negative patient: when we

Gross EA, Niedens BA. Validation of a decision instrument to limit pelvic

N

6.

U

break the rule. The American Journal of Emergency Medicine 2014;32:67-70.

7.

A

radiography in blunt trauma. The Journal of Emergency Medicine 2005;28:263-6. Barleben A, Jafari F, Rose J, et al. Implementation of a Cost-Saving Algorithm

M

for Pelvic Radiographs in Blunt Trauma Patients. The Journal of Trauma: Injury, Infection, and Critical Care 2011;71:582-4.

Civil ID, Ross SE, Botehlo G, Schwab CW. Routine pelvic radiography in severe

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8.

blunt trauma: Is it necessary? Annals of Emergency Medicine 1988;17:488-90. 9.

Duane TsM, Tan BB, Golay D, Cole FJ, Weireter LJ, Britt LD. Blunt Trauma and

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the Role of Routine Pelvic Radiographs: A Prospective Analysis. The Journal of Trauma: Injury, Infection, and Critical Care 2002;53:463-8. Holmes JF, Wisner DH. Indications and performance of pelvic radiography in

CC

10.

patients with blunt trauma. The American Journal of Emergency Medicine 2012;30:1129-33.

A

11.

Gonzalez RP, Fried PQ, Bukhalo M. The utility of clinical examination in

screening for pelvic fractures in blunt trauma1 1No competing interests declared. Journal of the American College of Surgeons 2002;194:121-5. 12.

Paydar S, Ghaffarpasand F, Foroughi M, et al. Role of routine pelvic

radiography in initial evaluation of stable, high-energy, blunt trauma patients. Emergency Medicine Journal 2012;30:724-7. 20

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Salvino CK, Esposito TJ, Smith D, et al. ROUTINE PELVIC X-RAY STUDIES

IN AWAKE BLUNT TRAUMA PATIENTS. The Journal of Trauma: Injury, Infection, and Critical Care 1992;33:413-6. 14.

Yugueros P, Sarmiento JM, Garcia AF, Ferrada R. Unnecessary Use of Pelvic

X-ray in Blunt Trauma. The Journal of Trauma: Injury, Infection, and Critical Care 1995;39:722-5. 15.

Shlamovitz GZ, Mower WR, Bergman J, et al. Poor Test Characteristics for the

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Digital Rectal Examination in Trauma Patients. Annals of Emergency Medicine 2007;50:25-33.e1.

Chang CH, Holmes JF, Mower WR, Panacek EA. Distracting injuries in patients

with vertebral injuries. J Emerg Med 2005;28:147-52. 17.

Heffernan DS, Schermer CR, Lu SW. What defines a distracting injury in

cervical spine assessment? J Trauma 2005;59:1396-9.

Ullrich A, Hendey GW, Geiderman J, Shaw SG, Hoffman J, Mower WR.

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18.

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16.

N

Distracting painful injuries associated with cervical spinal injuries in blunt trauma. Acad Emerg Med 2001;8:25-9.

den Boer TAW, Geurts M, van Hulsteijn LT, et al. The value of clinical

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19.

M

examination in diagnosing pelvic fractures in blunt trauma patients: a brief review. European Journal of Trauma and Emergency Surgery 2011;37:373-7. Tien IY, Dufel SE. Does ethanol affect the reliability of pelvic bone examination

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20.

A

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in blunt trauma? Annals of Emergency Medicine 2000;36:451-5.

21

Figure 1: Search method flow diagram with results

Searched independently by 2 reviewers: Cochrane, PubMed, EMBASE and Google Scholar

M

A

SC R

N

U

Relevant study titles / abstracts: 31

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Different combinations of the following key words were used: “Routine”, “Protocol”, “Initial Radiology”, “Radiology”, “Pelvic Radiology”, “Diagnostic Tests”, “Routine” [MESH], “Blunt Trauma” and “Trauma Patients”

Studies remained and meeting inclusion criteria for this systematic review: 10

A

CC

EP

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Full-text articles assessed for eligibility

22

21 full-text articles excluded for the following reasons: Retrospective studies (10), review articles (4), metaanalysis (1), included no awake patients (1), included patients already known to have a pelvic fracture (1), no description of physical examination (1), letter to editor (1), not available in full-text (2)

A

CC

EP

TE D

M

A

N

U

SC R

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Figure 2: Assessment of methodological quality and reporting bias

23

A

CC

EP

TE D

M

A

N

U

SC R

TP: true positive, FP: false positive, FN: false negative, TN: true negative

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Figure 3: TP, FP, FN, TN, sensitivity and specificity of PE for all pelvic fractures

24

Figure 4: Proposed decision making flow chart

ABC stable blunt trauma patient

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Otherwise: Pelvic x-ray (CT scan may be considered in GCS<13)

N

A

Patient has no: History 1. Subjective pelvic/hip pain

U

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Patient: Has a GCS ≥13 No direct surgical intervention required No communication barrier No distracting injury

M

Inspection 2. Bleeding/swelling pelvic area 3. Deformities or signs of hip dislocation

Otherwise: Pelvic x-ray

Routine pelvic x-ray can be safely omitted

A

CC

EP

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Testing 4. Paresthesia/neuropathy of groin/lower extremities 5. Tenderness to palpation of pelvic area 6. Pelvic instability 7. Pain during hip flexion/rotation

Note: analgesics administered prior to testing may mask pelvic tenderness. 25

Table 1: Summary of characteristics of included studies

GCS considered Mean age Study

N

m:f

Patients with Number of

to result in

Intoxicated

Propose pelvic

patients

X-ray as targeted test

negative PE

in years

pelvic fractures reliable

(% of N)

PE

Barleben 2011

978

642:336

38

59

921 (94.2)

mentioned

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Yes (in patients No GCS

unknown

undergoing CT during workup)

Civil 1988

133

unknown

32.5

15

0

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Included 110 (82.7)

(percentage

Yes

unknown)

520

336:139

34.1

≥13

unknown

Gonzalez 2002

2176

1338:838

35.9

≥14

96

Gross 2004

973

unknown

unknown

≥14

Holmes 2011

4737

unknown

39.8

83

Yes

1921 (88.3)

463

Yes

436 (44.8)

unknown

Yes

2592 (54.7)

unknown

N

M

A

62

348 (66.9)

U

Duane 2002

TE D

≥14

289

Yes (in patients undergoing CT during workup)

99

72:31

35

15

5

95 (95.6)

Excluded

Yes

Paydar 2013

389

283:106

32.1

≥14

1

389 (100)

unknown

Yes

Salvino 1992

810

532:278

33

≥13

39

746 (92.1)

295

Yes

33

≥10

59

524 (86.2)

unknown

Yes

608

443:165

CC

Yugueros 1995

EP

Koksal 2012

11423

8082 (70.6)

A

Total

26

Table 2: Physical examination performed in included studies

Barleben Civil Duane Gonzalez Gross Holmes Koksal Paydar Salvino Yugueros Physical examination

2011

HD stable

Bleeding and/or

1988 2002

2002

2004

2011

2012

2013

1992

1995

+

-

-

-

-

+

-

+

-

+

-

+

+

+

-

+

-

-

+

-

+

-

-

+

-

-

+

+

-

-

-

-

-

-

+

+

+

-

+

+

-

+

+

-

-

-

-

+

+

-

-

Deformities and/or

Intoxication and/or

Patient complaints of pelvic and/or

+

-

-

-

-

+

+

Tenderness during palpation (pelvis and/or lower back/

Pelvic instability

Pain during hip flexion/

CC

Rotation

-

+

+

+

+

+

+

+

+

+

-

+

+

-

-

+

-

-

-

+

-

-

+

+

-

-

-

+

+

-

-

-

+

+

-

-

-

-

+

-

EP

sacrum)

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M

extremities

A

Paresthesia or neuropathy of the groin and/or lower

-

N

hip pain

-

U

distracting injury

SC R

signs of hip dislocation

Gross blood or high riding

A

prostate upon rectal examination

27

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pelvic swelling

Table 3: Negative predictive value (NPV) and positive predictive value (PPV) of PE for pelvic fractures PPV for all

NPV for clinically

pelvic fractures

Pelvic fractures

relevant fractures

Barleben 2011

0.960

0.386

1

Civil 1988

1

0.348

1

Duane 2002

unknown

0.262

1

Gonzalez 2002

0.996

0.349

0.996

Gross 2004

0.995

0.112

Holmes 2011

0.994

0.128

Koksal 2012

0.968

0.500

Yugueros 1995

SC R U

relevance not reported clinical relevance not reported 1

0.996

0.679

1

0.991

0.178

0.991

0.173

A

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EP

Total excl. Duane/Paydar

clinical

0.563

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Total

M

0.996

1

unknown

A

0.997

Salvino 1992

0.998

N

Paydar 2013

28

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NPV for all

Study

Table 4: Patients with missed fractures and their clinical relevance Clinical relevance

Patients with missed pelvic fractures on PE

Fracture type (n)

and change in

a

(%)

management (n) femur (21), pubic bone (17), sacrum (17), coccyx

Barleben 2011 37 (4.0)

Duane 2002

Gonzalez 2002

None

0 (0)

-

-

Unknown

Unknown

None

acetabular (3), pubic rami (2), iliac wing (1),

7 (0.4)

Non-weight bearing (2),

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Civil 1988

(17), acetabulum (15), ilium (9), hip dislocation (1)

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Study

acetabular and rami (1)

weight bearing as tolerated (5)

non-displaced unilateral superior pubic ramus (1), Gross 2004

2 (0.5)

unilateral superior ramus and non-displaces iliac

Salvino 1992

Yugueros 1995

not mentioned

1 (0.3)

transverse fracture of pubic rami

not reported

3 (0.4)

type not mentioned, all stable fractures

None

2 (0.4)

a

N

3 (3.2)

A

Paydar 2013

not mentioned

M

Koksal 2012

Non-weight bearing (1)

15 (0.6)

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Holmes 2011

U

wing (1)

not mentioned

None

not reported

None

A

CC

EP

Percentage given is of the total of patients with negative findings during PE

29