The oblique view: an unnecessary component of the initial adult lumbar spine examination

The value of L5/S1 vertebral junction projection in diagnostic radiology

INTRODUCTION

The aim of this study was to compare the diagnostic contribution of the standard lateral and coned lumbar vertebra five and sacral vertebra one (L5/S1) projection in diagnostic radiology for specific pathologies in the digital era.

METHODS

The study used a retrospective qualitative design through a systematic stepwise process. The steps included a retrospective analysis of lumbar spine radiology reports over 20 months. The objective of this step was to identify the most common lumbar spine pathologies observed among the source population records (N=354). A radiologist identified five different pathologies on standard lateral and coned lateral L5/S1 projections (n=96). Fischer's exact test was performed to examine the significance of the association between the standard lateral and coned lateral L5/S1 projection classifications for each of the top five lumbar spine pathologies separately.

RESULTS

The five most prevalent lumbar spine pathologies indicated were degenerative disc disease (n=235; 66.4%), disc space narrowing (n=175; 49.4%), osteophytes (n=92; 26.0%), endplate sclerosis 19.21% (n=68; =9.2%) and malalignment (n=61; 17.2%). The Fisher's exact test executed to compare the top five lumbar spine pathologies visible on the standard lateral and coned lateral L5/S1 indicated that except for endplate sclerosis (p=0.0023), no significant difference in additional diagnostic information was observed between the standard lateral and coned lateral L5/S1 projections at α=0.05.

CONCLUSION

Compared to the standard lateral projection, the coned lateral L5/S1 projection did not contribute statistically significant additional diagnostic information for specific lumbar spine pathologies in the digital era.

Do oblique views add value in the diagnosis of spondylolysis in adolescents?

BACKGROUND

Anteroposterior, lateral, and right and left oblique lumbar spine radiographs are often a standard part of the evaluation of children who are clinically suspected of having spondylolysis. Recent concerns regarding radiation exposure and costs have brought the value of oblique radiographs into question. The purpose of the present study was to determine the diagnostic value of oblique views in the diagnosis of spondylolysis.

METHODS

Radiographs of fifty adolescents with L5 spondylolysis without spondylolisthesis and fifty controls were retrospectively reviewed. All controls were confirmed not to have spondylolysis on the basis of computed tomographic scanning, magnetic resonance imaging, or bone scanning. Anteroposterior, lateral, and right and left oblique radiographs of the lumbar spine were arranged into two sets of slides: one showing four views (anteroposterior, lateral, right oblique, and left oblique) and one showing two views (anteroposterior and lateral only). The slides were randomly presented to four pediatric spine surgeons for diagnosis, with four-view slides being presented first, followed by two-view slides. The slides for twenty random patients were later reanalyzed in order to calculate of intra-rater agreement. A power analysis demonstrated that this study was adequately powered. Inter-rater and intra-rater agreement were assessed on the basis of the percentage of overall agreement and intraclass correlation coefficients (ICCs). PCXMC software was used to generate effective radiation doses. Study charges were determined from radiology billing data.

RESULTS

There was no significant difference in sensitivity and specificity between four-view and two-view radiographs in the diagnosis of spondylolysis. The sensitivity was 0.59 for two-view studies and 0.53 for four-view studies (p = 0.33). The specificity was 0.96 for two-view studies and 0.94 for four-view studies (p = 0.60). Inter-rater agreement, intra-rater agreement, and agreement with gold-standard ICC values were in the moderate range and also demonstrated no significant differences. Percent overall agreement was 78% for four-view studies and 82% for two-view studies. The radiation effective dose was 1.26 mSv for four-view studies and 0.72 mSv for two-view studies (difference, 0.54 mSv). The charge for four-view studies was $145 more than that for two-view studies.

CONCLUSIONS

There is no difference in sensitivity and specificity between four-view and two-view studies. Although oblique views have long been considered standard practice by some, our data could not identify a diagnostic benefit that might outweigh the additional cost and radiation exposure.

Continuous quality improvement for patients with back pain

Recent evidence has changed traditional approaches to low back pain, suggesting minimal bed rest, highly selective imaging, and early return to normal activities. However, there are wide geographical variations in care, and substantial gaps between practice and evidence. This project sought to merge scientific evidence about back pain and knowledge about behavior change to help organizations improve care for back pain. Participating insurance plans, HMOs, and group practices focused on problems they themselves identified. The year-long program included quarterly meetings, coaching for rapid cycles of change, a menu of potential interventions, and recommendations for monitoring outcomes. Participants interacted through meetings, e-mail, and conference calls. Of the 22 participating organizations, 6 (27%) made major progress. Typical changes were reduced imaging, bed rest, and work loss, and increased patient education and satisfaction. Specific examples were a 30% decrease in plain x-rays, a 100% increase in use of patient education materials, and an 81% drop in prescribed bed rest. Despite the complexity of care for back pain, rapid improvements appear feasible. Several organizations had major improvements, and most experienced at least modest improvements. Key elements of successful programs included focus on a small number of clinical goals, frequent measurement of outcomes among small samples of patients, vigilance in maintaining gains; involvement of office staffs as well as physicians, and changes in standard protocols for imaging, physical therapy, and referral.

What help and what confusion can imaging provide?

Low back pain is a very common but benign and, in general, self-limiting disease indicating that only a small proportion of patients will require sophisticated imaging studies. Recent studies have highlighted the fact that a simple relationship of structural abnormalities to low back pain is impossible because similar alterations can be found in symptomatic as well as in asymptomatic individuals. these findings question our current criteria for the diagnosis of low back pain disorders with regard to their discriminative power in differentiating diseased and non-diseased individuals. Structural abnormalities demonstrated by imaging studies should therefore only be interpreted in the light of the clinical findings. This review shows that only a few studies contribute to our understanding of the clinical efficacy of imaging studies in the evaluation of low back pain disorders. There is an absolute need for comprehensive, well conducted studies on the impact of specific imaging modalities on diagnosis and treatment of lumbar spinal disease.

Detection of significant abnormalities on lumbar spine radiographs

The purpose of this study was to determine the proportion of significant abnormalities detected on anteroposterior (AP) and lateral radiographs of the lumbar spine when viewed separately, in a series of cases where the prevalence of abnormalities had been artificially increased. Five radiologists of varying experience were required to report separately on the AP and lateral films of 300 cases in which randomly included were 30 cases with metastatic disease, a disc infection or an inflammatory spondylitis. At a later date, unaware of their initial observations, the radiologists repeated the exercise reviewing all the films together. As might be expected the false positive rate was relatively high, particularly in the least experienced radiologists' responses. Nevertheless the overall results indicate that the majority of early inflammatory spondylitis cases will be missed on a solitary lateral film as will many of the metastases. Conversely, fractionally more of the disc infections were observed on the lateral film than on the AP. Further analyses in terms of sensitivity, specificity, positive and negative predictive values are presented. The authors conclude that it is preferable to reduce the overall number of lumbar spine examinations performed, by adherence to accepted guidelines, than to prejudice the detection of significant, albeit rare, abnormalities by restricting the routine series of radiographs.

Guidelines for use of lumbar spine radiography

In deciding whether to obtain lumbosacral spine films, the emergency physician must not ask whether a diagnosis can be established, but whether obtaining films will affect management. Low back pain is a considerable problem for society with cost in billions of dollars. Gonadal radiation from lumbosacral radiographs is significant, and thus ordering films should be minimized. Plain radiographs are rarely indicated in otherwise healthy patients 20 to 50 years old with mechanical or root pain on initial presentation. In other patients alternative diagnostic methodologies such as computed tomography may be superior, with less radiation risk. Specific recommendations for emergency radiographic evaluation of the lumbosacral spine are offered.

Use of radiographic projections of knee

A study to determine the routine radiography practice for the investigation of acute trauma cases and those with suspected arthritis of the knee was carried out by questionnaires sent to radiologists in 41 countries. The role of radiology in the investigation of chondromalacia patellae was also ascertained. Some of the reasons for the diversities of practice are discussed. The necessity for further views of the knee to supplement the two standard projections was assessed for various diagnostic entities. It became clear that if occult fractures were not to be missed, patients with knee effusions following acute trauma required additional views if a lesion was not shown by the anteroposterior (AP) and lateral views. In contrast, two views of the knee sufficed for examination of most entities affecting the knee.

Symptomatic and asymptomatic spondylolysis and spondylolisthesis in young adults

The lumbar spine was examined radiologically for the presence of spondylolysis and spondylolisthesis in 936 asymptomatic soldiers prior to military placement and in 662 soldiers complaining of low back pain. The overall incidence of spondylolysis was 9.7% in both groups, but bilateral spondylolysis was more prone to be associated with symptoms than a unilateral defect. In the symptomatic group the incidence of spondylolisthesis was 5.3% but only 2.2% in the asymptomatic group. The defect was seen in the oblique views only in 18.7% of the cases of spondylolysis. The precise diagnosis is important for vocational counselling and military placement.