1990, The British Journal of Radiology, 63, 535-536
Assessment of a single lumbar spine radiograph in low back pain By *S. Padley, MRCP, F. Gleeson, MRCP, FRCR, R. Chisholm, MRCP, FRCR and J. Baldwin, MRCP, FRCR Department of Radiology, Addenbrooke's Hospital, Hills Road, Cambridge (Received December 1989 and in revised form February 1990) Abstract. The lumbosacral spine radiographs of 200 patients with unexplained low back pain and without neurological signs were reviewed. The purpose of the study was to determine whether significant diagnostic information would be lost by replacing the standard three film series with a single radiograph, either in the lateral or antero-posterior projection. The contribution of the coned lumbosacral junction view was also assessed. The results show that a single lateral radiograph is diagnostically satisfactory and would have the added advantages of reducing patient radiation dose and radiographic workload.
The use of radiological services needs to be rationalized in order to control increasing demand and reduce patient irradiation. The standard lumbar spine series (antero-posterior (AP), lateral and coned lateral of the lumbosacral junction (LSJ)) account for some 3.5% of all radiological investigations (Brekkan, 1983). In addition, the radiation dose from the standard three film series is considerable, imparting a total body dose of 3.86 mSieverts (mSv). This is equivalent to about 66 lowkV chest radiographs, which have an individual dose of approximately 0.058 mSv (IRCP, 1982). The value of lumbar spine radiography is in doubt when used as an initial investigation in low back pain without obvious cause (Currey et al, 1979; Waddell, 1982; Butt, 1989). The aim of this study was to determine whether a single AP or lateral radiograph could replace the standard three film series, and also to assess the contribution of the coned LSJ view. Methods
The radiographs of 200 patients referred by their general practitioners with low back pain, and in whom there was no suspicion of malignancy or infection, no history of trauma and no neurological signs, were reviewed by a radiologist (J.B. or R.C.). The patients' radiographs were divided into two equal groups of 100. The AP projection was viewed first in Group 1 and the nature and severity of any abnormality was recorded according to the categories shown in Table I. After subsequent review of the lateral radiograph, any change in the observations was recorded (Table II). Finally, the LSJ film was viewed and any further change in the overall assessment was documented (Table HI). The same procedure was used in the second group except that the lateral projection was viewed first. Results
The influence of the second film on the final assessment (Table II) was found to be greatest when the AP was viewed first (Group 1), resulting in a change in 32% *Author for correspondence. Vol. 63, No. 751
Table I. Diagnostic categories and grades of severity Category
Severity
1. Normal 2. Spondylosis
(a)
Minimal osteophytes, no disc space loss (b) Larger osteophytes affecting more than three vertebrae (c) As (b) but with disc space loss 3. Osteoporosis (a) No collapse (b) End plate collapse (c) Vertebral body collapse (a) Spondylolysis 4. Osteoarthrosis of facet joints and pars (b) Spondylolisthesis defects (c) (a) and (b) 5. Other e.g. Old osteochondritis
of cases, as compared with 3% when the lateralfilmwas viewed first (Group 2). In 23% of cases in Group 1, a further diagnostic category was added, whilst in 8%, there was an increase in the severity of the pathology demonstrated. In no case was significant diagnostic information lost by examination of a single film, be it Table II. Influence of additional radiograph on original assessment of a single projection Change in observations
Group 1 (AP first) (%)
No change 68 Change of severity 8 Increase 0 Decrease Addition of further 23 category Addition of further category and change in severity 0 Increase 1 Decrease
Group 2 (lateral first) (%) 97 0 0 0
3 0
535
S. Padley, F. Gleeson, R. Chisholm and J. Baldwin Table III. Change of report after addition of third radiograph (LSJ) to series Change in overall assessment
% of total
No change Change
96 4
the AP or lateral. Additional information was gained from the LSJ view in 4% of cases (Table III). In all of these cases, the junction was excluded from the lateral film or was so underpenetrated as to be uninterpretable. In no case would this additional information have altered patient management. Discussion
Low back pain is the second largest medical cause of lost work in the UK after chronic bronchitis (British Medical Journal, 1979) and causes more days of lost work than industrial action (Waddell, 1982). As most patients with low back pain recover within a few weeks on conservative management (Currey et al, 1979; Butt, 1989), it can be argued that plain radiography has little to offer in the initial assessment of this condition. Currey et al (1979) have suggested that radiographs should be reserved for second line investigation of those patients whose symptoms have not settled after 3 months of conservative treatment. In addition, they felt that plain radiography had little to offer when the history and examination failed to indicate a specific pathology. Indeed, in those cases where a particular pathology was found, it had generally been suspected prior to the radiographic examination, often to the extent of being documented in the case notes. Neither their findings nor ours support the notion that plain radiographs are justified to detect occasional but unsuspected pathology such as ankylosing spondylitis or metastases. We would concur with their suggestion that the erythrocyte sedimentation rate (ESR) and other simple blood tests are more appropriate initial investigations. With this background, it is not suprising that
536
we have found that limiting the radiological investigations to a single lateral film has no influence on the final diagnosis. Despite this, it is likely that plain radiographs of the lumbar spine will continue to be requested as the initial investigation of low back pain, a practice which we believe should be increasingly questioned. Although limiting the examination to a single lateral film would appear to be a logical step, it might reasonably be argued that if the value of the test is in doubt it should not be performed at all. Our study indicates that a single lateral view, obtained using the technique described by Eisenberg et al (1979), would miss no significant pathology demonstrated on the conventional three film lumbar spine series. We suggest that the introduction of a single lateralfilmpolicy in patients with low back pain with no apparent or suspected cause should be acceptable medical practice. We do not feel that this could be reasonably opposed on medico-legal grounds. Such a policy would have added the advantages of reducing patient radiation dosage and radiographic workload. Prior screening of requests for lumbar spine radiographs would determine whether additional films were warranted in any particular clinical situation. References BREKKAN, A., 1983. Radiographic examination of the lumbosacral spine: an "age stratified" study. Clinical Radiology, 34, 321-324. BRITISH MEDICAL JOURNAL, 1979. Back pain—what can we
offer? (Editorial). British Medical Journal, 2, 709. BUTT, W. P., 1989. Radiology of back pain. Clinical Radiology, 40, 6-10. CURREY, H. L. F., GREENWOOD, R. M., LLOYD, G. G. &
MURRAL, R. S., 1979. A prospective study in low back pain. Rheumatology and Rehabilitation, 18, 94-104. EISENBERG, R. L., ATKIN, J. R. & HEDGCOCK, M. W., 1979.
Single well centred lateral view of the lumbosacral spine: is a coned view necessary? American Journal of Roentgenology, 133, 711-713. ICRP, 1982. Protection of the patient in diagnostic radiology. Annals of the ICRP, 9, 52. WADDELL, G., 1982. An approach to backache. British Journal of Hospital Medicine, 28, 182-218.
The British Journal of Radiology, July 1990
Assessment of a single lumbar spine radiograph in low back pain By *S. Padley, MRCP, F. Gleeson, MRCP, FRCR, R. Chisholm, MRCP, FRCR and J. Baldwin, MRCP, FRCR Department of Radiology, Addenbrooke's Hospital, Hills Road, Cambridge (Received December 1989 and in revised form February 1990) Abstract. The lumbosacral spine radiographs of 200 patients with unexplained low back pain and without neurological signs were reviewed. The purpose of the study was to determine whether significant diagnostic information would be lost by replacing the standard three film series with a single radiograph, either in the lateral or antero-posterior projection. The contribution of the coned lumbosacral junction view was also assessed. The results show that a single lateral radiograph is diagnostically satisfactory and would have the added advantages of reducing patient radiation dose and radiographic workload.
The use of radiological services needs to be rationalized in order to control increasing demand and reduce patient irradiation. The standard lumbar spine series (antero-posterior (AP), lateral and coned lateral of the lumbosacral junction (LSJ)) account for some 3.5% of all radiological investigations (Brekkan, 1983). In addition, the radiation dose from the standard three film series is considerable, imparting a total body dose of 3.86 mSieverts (mSv). This is equivalent to about 66 lowkV chest radiographs, which have an individual dose of approximately 0.058 mSv (IRCP, 1982). The value of lumbar spine radiography is in doubt when used as an initial investigation in low back pain without obvious cause (Currey et al, 1979; Waddell, 1982; Butt, 1989). The aim of this study was to determine whether a single AP or lateral radiograph could replace the standard three film series, and also to assess the contribution of the coned LSJ view. Methods
The radiographs of 200 patients referred by their general practitioners with low back pain, and in whom there was no suspicion of malignancy or infection, no history of trauma and no neurological signs, were reviewed by a radiologist (J.B. or R.C.). The patients' radiographs were divided into two equal groups of 100. The AP projection was viewed first in Group 1 and the nature and severity of any abnormality was recorded according to the categories shown in Table I. After subsequent review of the lateral radiograph, any change in the observations was recorded (Table II). Finally, the LSJ film was viewed and any further change in the overall assessment was documented (Table HI). The same procedure was used in the second group except that the lateral projection was viewed first. Results
The influence of the second film on the final assessment (Table II) was found to be greatest when the AP was viewed first (Group 1), resulting in a change in 32% *Author for correspondence. Vol. 63, No. 751
Table I. Diagnostic categories and grades of severity Category
Severity
1. Normal 2. Spondylosis
(a)
Minimal osteophytes, no disc space loss (b) Larger osteophytes affecting more than three vertebrae (c) As (b) but with disc space loss 3. Osteoporosis (a) No collapse (b) End plate collapse (c) Vertebral body collapse (a) Spondylolysis 4. Osteoarthrosis of facet joints and pars (b) Spondylolisthesis defects (c) (a) and (b) 5. Other e.g. Old osteochondritis
of cases, as compared with 3% when the lateralfilmwas viewed first (Group 2). In 23% of cases in Group 1, a further diagnostic category was added, whilst in 8%, there was an increase in the severity of the pathology demonstrated. In no case was significant diagnostic information lost by examination of a single film, be it Table II. Influence of additional radiograph on original assessment of a single projection Change in observations
Group 1 (AP first) (%)
No change 68 Change of severity 8 Increase 0 Decrease Addition of further 23 category Addition of further category and change in severity 0 Increase 1 Decrease
Group 2 (lateral first) (%) 97 0 0 0
3 0
535
S. Padley, F. Gleeson, R. Chisholm and J. Baldwin Table III. Change of report after addition of third radiograph (LSJ) to series Change in overall assessment
% of total
No change Change
96 4
the AP or lateral. Additional information was gained from the LSJ view in 4% of cases (Table III). In all of these cases, the junction was excluded from the lateral film or was so underpenetrated as to be uninterpretable. In no case would this additional information have altered patient management. Discussion
Low back pain is the second largest medical cause of lost work in the UK after chronic bronchitis (British Medical Journal, 1979) and causes more days of lost work than industrial action (Waddell, 1982). As most patients with low back pain recover within a few weeks on conservative management (Currey et al, 1979; Butt, 1989), it can be argued that plain radiography has little to offer in the initial assessment of this condition. Currey et al (1979) have suggested that radiographs should be reserved for second line investigation of those patients whose symptoms have not settled after 3 months of conservative treatment. In addition, they felt that plain radiography had little to offer when the history and examination failed to indicate a specific pathology. Indeed, in those cases where a particular pathology was found, it had generally been suspected prior to the radiographic examination, often to the extent of being documented in the case notes. Neither their findings nor ours support the notion that plain radiographs are justified to detect occasional but unsuspected pathology such as ankylosing spondylitis or metastases. We would concur with their suggestion that the erythrocyte sedimentation rate (ESR) and other simple blood tests are more appropriate initial investigations. With this background, it is not suprising that
536
we have found that limiting the radiological investigations to a single lateral film has no influence on the final diagnosis. Despite this, it is likely that plain radiographs of the lumbar spine will continue to be requested as the initial investigation of low back pain, a practice which we believe should be increasingly questioned. Although limiting the examination to a single lateral film would appear to be a logical step, it might reasonably be argued that if the value of the test is in doubt it should not be performed at all. Our study indicates that a single lateral view, obtained using the technique described by Eisenberg et al (1979), would miss no significant pathology demonstrated on the conventional three film lumbar spine series. We suggest that the introduction of a single lateralfilmpolicy in patients with low back pain with no apparent or suspected cause should be acceptable medical practice. We do not feel that this could be reasonably opposed on medico-legal grounds. Such a policy would have added the advantages of reducing patient radiation dosage and radiographic workload. Prior screening of requests for lumbar spine radiographs would determine whether additional films were warranted in any particular clinical situation. References BREKKAN, A., 1983. Radiographic examination of the lumbosacral spine: an "age stratified" study. Clinical Radiology, 34, 321-324. BRITISH MEDICAL JOURNAL, 1979. Back pain—what can we
offer? (Editorial). British Medical Journal, 2, 709. BUTT, W. P., 1989. Radiology of back pain. Clinical Radiology, 40, 6-10. CURREY, H. L. F., GREENWOOD, R. M., LLOYD, G. G. &
MURRAL, R. S., 1979. A prospective study in low back pain. Rheumatology and Rehabilitation, 18, 94-104. EISENBERG, R. L., ATKIN, J. R. & HEDGCOCK, M. W., 1979.
Single well centred lateral view of the lumbosacral spine: is a coned view necessary? American Journal of Roentgenology, 133, 711-713. ICRP, 1982. Protection of the patient in diagnostic radiology. Annals of the ICRP, 9, 52. WADDELL, G., 1982. An approach to backache. British Journal of Hospital Medicine, 28, 182-218.
The British Journal of Radiology, July 1990
