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 Table of Contents  
ORIGINAL RESEARCH REPORT
Year : 2018  |  Volume : 15  |  Issue : 4  |  Page : 201-206

Evaluation of the usefulness of plain radiography in the imaging of nontraumatic neck pain: A retrospective survey at a tertiary hospital in Lagos, Nigeria


1 Department of Medical Radiography, Faculty of Clinical Sciences, College of Medicine, University of Lagos, Surulere, Lagos, Nigeria
2 Department of Medical Radiography, Faculty of Health Sciences, College of Medicine, Nnamdi Azikiwe University, Nnewi, Anambra, Nigeria

Date of Web Publication3-Dec-2018

Correspondence Address:
Dr. Cletus Uche Eze
Department of Medical Radiography, Faculty of Clinical Sciences, College of Medicine, University of Lagos, Ishaga Road, Idi-Araba, Surulere, Lagos
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jcls.jcls_51_18

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  Abstract 


Background: Plain radiography rather than magnetic resonance remains the first-line modality in the evaluation of patients with nontraumatic neck pain (NNP) in most hospitals in Lagos, Nigeria. Objective: The objective of the study is to determine the usefulness of plain radiography in the detection of causes of NNP. Subjects and Methods: A sample of 596 patients was evaluated in a retrospective study carried out at a tertiary hospital. Request forms were used to sort patients into the type of X-ray views requested by physicians while radiologists' reports were used to sort patients according to radiological findings, type of X-ray views, and type of imaging modality requested by radiologists for further evaluation of patients. Results: No abnormality detected was reported in 67.6% of patients while computed tomography or magnetic resonance imaging was requested for further evaluation in 74.6% of patients. Physicians requested anteroposterior (AP) and lateral views for most patients (71.1%) while AP, both oblique and lateral as well as AP, open-mouth, and lateral views were requested for 12.5% and 16.4% of patients, respectively. Radiologists requested either oblique or open-mouth view for 214 patients after film review. The mean age of patients was 46 ± 6 years; 39.3% of patients were men while 60.7% were women; pain was most common after the 5th decade of life. Conclusion: Plain radiography was useful in the evaluation of patients with NNP in the tertiary hospital studied although it was not totally done in line with any standardized pathway for imaging of patients with NNP.

Keywords: Imaging pathway, neck pain, Nigeria, plain radiography


How to cite this article:
Eze CU, Ohagwu CC, Abonyi LC, Irurhe NK, Ayeni TA. Evaluation of the usefulness of plain radiography in the imaging of nontraumatic neck pain: A retrospective survey at a tertiary hospital in Lagos, Nigeria. J Clin Sci 2018;15:201-6

How to cite this URL:
Eze CU, Ohagwu CC, Abonyi LC, Irurhe NK, Ayeni TA. Evaluation of the usefulness of plain radiography in the imaging of nontraumatic neck pain: A retrospective survey at a tertiary hospital in Lagos, Nigeria. J Clin Sci [serial online] 2018 [cited 2019 Jan 23];15:201-6. Available from: http://www.jcsjournal.org/text.asp?2018/15/4/201/246767




  Introduction Top


Chronic nontraumatic neck pain (NNP) is a frequent cause of consultation and therefore a major global public health problem. It affects about two-thirds of the adult population globally at one time or the other.[1] Although nonspecific neck pain resolves within days, it persists in about 10% of patients and results in algofunctional consequences responsible for physical disability and high health-care cost.[1] According to Hoy et al.,[2] the overall global 12 months and point prevalence of NNP ranged between 0.4% and 86.8% (mean: 23.1%), 4.8% and 79.5% (mean: 25.8%), and 0.4% and 41.5% (mean: 14.45%), respectively. Ogwumike et al.[3] attributed these differences in prevalence to differences in study population and genetic dispositions of participants. NNP is the second most common musculoskeletal presenting complaint[4] and the 12th most common overall presenting complaint in the primary care setting.[5] Neck pain is generally more common among women and more common among urban than rural dwellers.[1],[3],[6],[7] In Sweden, for instance, 43% of the working population are affected with 2 out of 5 males and 1 out of 4 females within the age range of 45–75 years having NNP.[6] In a university in Nigeria, 47.2% and 52.8% of male and female students, respectively, had chronic NNP,[8] with NNP equally reported to be common among dentists and dental auxiliaries in Nigeria.[9]

There are several evidence-based diagnostic imaging practice guidelines for musculoskeletal complaints in adults.[10],[11],[12] Such standardized diagnostic pathways provide guidance on referral and imaging of adults with NNP in line with evidence-based practice. Consequently, it is an accepted best practice that physicians ought to observe “red flags” [Figure 1] such as immunosuppression, intravenous drug use, history of malignancy or unexplained weight loss of insidious onset, age >50 years, prolonged use of corticosteroids, osteoporosis, suspected or diagnosed rheumatological condition, and neurological signs or symptoms, for example., headache, dysphagia, vomiting, and focal neurologic deficit and use them as criteria in selecting patients to be referred for plain radiography in the investigation of the cause of NNP so as to increase its diagnostic yield.[10] In patients with NNP, magnetic resonance imaging (MRI) is not just the preferred first-line advanced imaging examination but should equally be performed if there are neurologic signs or symptoms, regardless of radiographic findings.[10] The sensitivity of MRI to detect cervical soft disc herniation is 94%; hence, it is the most accurate modality for detecting suspected malignancy and vertebral metastasis and determining disease extension around the spinal cord.[13],[14] MRI equally has high accuracy, sensitivity, and specificity in detecting vertebral compression fractures and can provide clues to differentiate malignant, osteoporotic, and infective causes and gives a better soft-tissue contrast which allows for evaluation of soft-tissue and osseous abnormalities.[15],[16],[17] Limited availability and high cost are, however, relative contraindications of MRI in resource-poor countries. Where MRI is either not available or is not advisable as may be the case in patients with metallic pacemakers and in those who are claustrophobic, computed tomography (CT) can be used to provide satisfactory results.[18] CT provides superior bone detail and is less sensitive to patient movements compared to MRI and hence its usefulness where bony anatomy is critical or in surgical planning.[10] In spite of this, CT is associated with ionizing radiation, and like in other imaging tests, abnormalities usually detected by CT including herniated discs and degenerative changes are sometimes detected in asymptomatic individuals, thereby reducing its specificity.[10]
Figure 1: Diagnostic imaging pathways – neck pain (nontraumatic)

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To the best our knowledge, there is no national guideline on the imaging of patients with NNP in Nigeria. To make matters worse, local rules on radiological procedures are not well defined in most tertiary hospitals including ours. It is little wonder then that we observed plain radiography often being done as the first-line imaging modality (in some cases, it is actually the only one) in the radiological investigation of NNP in our center. Requests for X-ray investigation of NNP in our center usually come from clinicians and go to senior radiographers who distribute them to radiographers working in diagnostic rooms for examination. In the absence of a standardized local protocol to use as a guide, radiographers in our center usually perform anteroposterior (AP) and lateral projections as requested by most physicians. The number of plain X-ray views (2 0r 3) done in the hospital studied is less than 5views recommended for evaluation of patients with NNP.[11] Even when less than five views were recommended, AP (for lower cervical), AP open-mouth (for upper cervical), and lateral radiographs are mandatory views to be done for NNP adult patients with radicular symptoms.[19] Rather, unfortunately, we observed that most radiographers in our center were not willing to do an additional oblique or open-mouth view for patients with NNP when the physician did not request them simply because of fear of who will pay for additional films used. Without the recommended number and type of views being done, plain radiographs may fail to provide needed answer(s) to the clinical question raised by the referring clinician. Even if a radiologist requests an additional view after the initial examination (they often do so in our center anyway), precious time would have been lost if the referring clinician were to tinker the patient's management regimen based on the radiologist's report.

Even when the recommended number and type of views are done, plain radiography is said to serve poorly either as a diagnostic or screening test in NNP as most patients with NNP have either normal cervical spine radiographs or age-related degenerative changes often not related to symptoms.[10],[14],[20] Due to its poor sensitivity, the use of plain radiography in the investigation of the cause of NNP is described as inappropriate.[10] With this in mind, developers of standardized imaging pathways and appropriateness criteria recommend that plain radiography is not indicated except for patients with “red flag” features suggestive of serious underlying disease are present or symptoms have persisted for more than 6 weeks.[10],[20] With medical exposure to ionizing radiation being steadily on the increase in the last two decades,[21] we believe that the use of plain radiography which is poorly sensitive and nonspecific[10],[20] in the evaluation of patients with NNP could unnecessarily contribute significantly to patient dose, especially if a standardized imaging pathway is not strictly adhered to. We, therefore, carried out a retrospective evaluation of plain cervical X-ray examinations and radiologists' reports in a tertiary hospital in Lagos, Southwest Nigeria, to determine the usefulness (or otherwise) of plain cervical radiography in the detection of cause(s) of NNP. The study was also carried out to determine whether plain radiography was done in line with standardized appropriateness criteria for imaging of patients with NNP.


  Subjects and Methods Top


In the retrospective survey carried out between November 2016 and October 2017, a convenience sample of 596 plain cervical radiographs was evaluated. The Health Research and Ethics Committee at the hospital reviewed and approved our research proposal. Only patients aged 18 years and above who had no history of trauma but presented with persistent/recurrent neck pain and were referred for plain radiography of the cervical spine were included in the study. Patients whose X-ray request forms were not completed and signed by a physician, those whose radiographs were not reported by a radiologist, and those whose X-ray jackets and/or radiologist's report were not found were excluded from the study.

Data collection

Patients with NNP within the study period were identified from the departmental X-ray register. X-ray numbers were thereafter used to retrieve X-ray jackets, X-request forms, and radiologists' reports. Patient's sex, age, type of X-ray views requested, type of views actually done, the radiologist's diagnosis, and type of additional views requested by radiologists were recorded.

Data analysis

Patients were sorted into sex and age groups. Thereafter, patients were sorted into the type of views requested by physicians, type of views done by radiographers, radiological diagnosis, and type of additional views requested by the radiologist, respectively. Descriptive statistics such as mean plus standard deviation (for the age of patients) and proportion were computed for each category. Proportions were compared using Chi-square test. The proportion of patients who were referred for both oblique and open-mouth view by physicians and radiologists was computed and compared using Chi-square test. Thereafter, radiologists' reports were used to sort patients into groups with no abnormality detected (NAD), specific radiological diagnosis, and those referred for further evaluation using CT or MRI. Proportions were computed for all the groups after which the proportion of patients who had all three views (AP, both oblique and open mouth, and lateral) before films were reported was used to determine the conformity of plain radiography to standardized imaging protocol, while the proportion of patients who had specific radiological diagnosis was used to determine the usefulness of plain cervical radiography in the investigation of NNP. Data were managed using Epi-Info computer software version 3.2 (Windows 9x, NT 4.0, 2000, XP of Microsoft Inc; Redmond, Washington DC, USA), while alpha was set at 0.05.


  Results Top


NAD was reported in 67.6% of patients, while CT or MRI was requested for further evaluation in 74.6% of patients who had “specific radiological diagnoses” [Table 1]. Physicians requested only AP and lateral views for most patients (71.1%) but requested AP, both oblique and lateral, and AP open-mouth and lateral views in 12.5% and 16.4% of patients, respectively. Radiographers did all the views requested for each patient by physicians without alteration during examination [Table 2]. Radiologists, on the other hand, made additional 214 plain X-ray requests for both oblique and open-mouth views [Table 3] but placed a higher premium on both oblique and open-mouth views (109 and 105 additional requests, respectively) than physicians [P < 0.05; [Table 4]. The mean age of the 596 patients reviewed was 46 ± 6 years. Out of the 596 patients, 234 (39.3%) were men while 362 (60.7%) were women, while NNP was most common after the fifth decade of life [Figure 2].
Table 1: Findings from plain cervical spine radiographs and imaging modality requested by radiologists for further evaluation of some patients

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Table 2: Type of X-ray view requested by referring clinicians and type of X-ray view done during examination

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Table 3: Type of additional X-ray view done on request by radiologists

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Table 4: Comparison of the proportion of oblique and open-mouth views requested by both physicians and radiologists

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Figure 2: Bar charts showing that the development of nontraumatic neck pain tends to increase with the age of patients

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  Discussion Top


In the retrospective study designed to determine whether plain radiography was useful in detecting the cause of NNP as well as to ascertain whether plain radiography was performed in conformity with standardized pathway for imaging of patients with NNP in a tertiary hospital in Lagos, Nigeria, we found that it played a rather marginal role. This is because plain radiography did not detect any abnormality in most patients evaluated. With this result, we agree with the opinion of the Australian Acute Musculoskeletal Pain Guidelines Group[14] that “plain radiography serves poorly either as a diagnostic or screening test in NNP.” In particular, plain radiography did not perform satisfactorily as far as making of specific diagnosis of the cause of NNP in the present study is concerned with the radiologist making what we termed “specific diagnoses” in just 32.4% of patients reviewed. We are of the view that the proportion (74%) of patients with NNP who had 'specific radiological diagnoses and yet were referred for further evaluation using CT or MRI also highlights the marginal role played by PR in the imaging of NNP as we earlier pointed out. Although we could not trace their result, the large proportion of patients (74%) who were referred to undergo further evaluation using MRI or CT implies that radiologists were not convinced beyond a doubt that definitive diagnoses were actually made in spite of initial plain X-ray diagnoses. The rather small proportion of patients with specific radiological diagnoses in the present study supports the notion that plain radiography is not sensitive and nonspecific in detection of the cause(s) of NNP.[9],[10],[20]

We also found that the request for plain radiography was largely not in conformity with standardized protocol for imaging of patients with NNP because most physicians requested only AP and lateral views for most patients. This is contrary to the recommended “five-view” radiography as the first-line imaging procedure for a patient of any age with NNP or a patient of any age with a history of malignancy or surgery.[10],[11],[12] This is also not in line with the view of Bussières et al.[11] who opined that “AP, open-mouth, lateral, and both oblique (rarely) radiographs are indicated for adult patients with NNP and radicular symptoms.” Surprisingly, there was no evidence to show that patients with NNP in the present study had radicular syndrome as information pertaining to that was not given in the X-ray request forms. The omission of this vital information is similar to a previous report that most physicians in a tertiary hospital in Lagos, Nigeria, did not include important details in the patients' X-ray request forms.[22] To us though, it was not a surprise that radiologists in the hospital studied laid slightly more emphasis on both oblique than open-mouth view and equally placed a significantly higher premium on oblique and open-mouth views than other physicians probably because they (radiologists) are more conversant with diagnostic imaging best practices. The obvious disparity in type of plain X-ray requested by physicians and radiologists in the center could be attributed not only to the absence of a standardized imaging protocol for patients with NNP in Nigeria but also probably to the lack of synergy between medical (physicians) and radiology staff (radiographers and radiologists). In our view, therefore, plain radiography done in the evaluation of NNP in the present study could possibly have resulted in some patients being unnecessarily exposed to ionizing radiation during the period under review. It is, however, interesting to note that radiologists did request MRI and CT for further evaluation of patients with inflammatory and bone lesion, respectively. While this is in line with the opinion of Laker and Concannon,[19] it is pertinent to point out that not a single patient with “NAD” was referred for further evaluation. We do agree that most of those patients with NAD did not need further imaging evaluation. It is, however, likely that the few who might have needed them were not referred. This is important when we take the view that “negative radiographs” do not necessarily clear the patient when certain red flags are present[11] into cognizance.

In a sub-Sahara region of Africa where more men than women seek medical care due to the low-financial status of women as well as religious and cultural practices that hinder them,[23] it is rather a surprise that more women than men presented with NNP within the period studied. The predominance of women in the present study is in line with the widely reported notion that more women than men develop NNP.[1],[4],[5],[7] It is not unlikely that genetic differences and posture played roles in the development of NNP in both sexes. We are, however, inclined to believe that hormonal changes might just explain why more women had NNP. Although we did not establish their hormonal profile, it has been reported that women who are experiencing hormonal changes or are taking birth control pills or who are undergoing hormone replacement therapy tend to develop neuromuscular disorders.[24]

It is common knowledge that chronic NNP is associated with daily activities, improper body mechanics, psychological stress, and physiological changes, and it becomes more common with advancing age. In the present study, however, NNP was not restricted to any particular age group [Figure 2] although patients after their fifth decade of life were the most affected. Although we did not determine the impact of daily activities, improper body mechanics, psychological stress, and physiological changes on the development of NNP in the present study, the fact that the age range of patients was skewed toward those more than 40 years appears significant. The age distribution clearly suggests that the development of NNP is probably a gradual process that tends to reach a peak after the fifth to the sixth decade of life. This view seems to support that of Palmer et al.[21] who had earlier reported that age is a greater contributor to chronic neck pain than occupation.

A major limitation of the present study is that sensitivity and specificity of plain radiography in the diagnosis of NNP were not computed. Generalization of results from the present study could also be limited by the fact that only a single tertiary hospital in Lagos metropolis was studied. Another limitation of the study is that we did not include results of subsequent CT scans or MRI examination requested by radiologists for further evaluation of some patients with NNP as we believe that such results could have made our conclusion more interesting.


  Conclusion Top


In the tertiary hospital studied in Lagos, Southwest Nigeria, plain radiography played a role (albeit marginally) in the diagnosis of cause(s) of NNP in spite of the fact that it was largely not done in line with recommended diagnostic imaging pathways. An apparent lack of synergy found between physicians and radiologists on one hand, and between radiographers and radiologists on the other; brevity of clinical information with little reference to 'red flags' as well as inadequate number and type of plain X-ray views requested by physicians adversely affected the usefulness of PR in the diagnosis of the cause of NNP. Consequently, it is highly possible that some patients were subjected in the population studied were subjected to unnecessary exposure to ionizing radiation within the period reviewed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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