Controversy. The use of selective nerve root blocks: diagnostic, therapeutic, or placebo?

Diagnosis and Treatment of Transforaminal Epidural Steroid Injection in Lumbar Spinal Stenosis

Objectives:

Transforaminal epidural steroid injection reduces the low back-leg pain and enables daily activities of the patients. In this study, we aim to evaluate the treatment of transforaminal epidural steroid injection for lumbar spinal stenosis, which was mainly performed for lumbar disc herniation and share our diagnostic experience for lumbar spinal stenosis which is treated surgically.

Methods:

In our study, 37 patients were included who were treated by transforaminal epidural steroid injection for Grade B lumbar spinal stenosis in our clinic between June-2014 and June-2018. We evaluated the patients at the second weeks, third/sixth months and one year after the treatment by Oswestry-Disability-Index and Visual-Analogue-Scale and followed up for surgical treatment after one year.

Results:

The mean low back and leg pain Visual Analogue Scale was 5.1±0.3 before the transforaminal epidural steroid injection procedure, and it was 2.7±0.1 after two weeks. It was 2.8±0.2, 3.1±0.1 at three and six months after procedure, respectively. The improvement of low back-leg pain mean Visual-Analogue-Scale is statistically significant at two weeks, three and six months after transforaminal epidural steroid injection procedure, respectively. The mean Oswestry-Disability-Index was 29.6±0.4 before the transforaminal epidural steroid injection procedure, and it was 14.1±0.3 after two weeks. It was 15.3±0.5, 24.4±0.2 at three and six months after procedure, respectively. The improvement of Oswestry-Disability-Index is statistically significant at two weeks, three-six months.

Conclusion:

The transforaminal epidural steroid injection is safe procedure for non-surgical treatment of lumbar spinal stenosis and this procedure may be preferred support to the indication of the surgical treatment of level of lumbar spinal stenosis.

The Utility of Diagnostic Transforaminal Epidural Injection in Selective Percutaneous Endoscopic Lumbar Discectomy for Multilevel Disc Herniation with Monoradicular Symptom: A Prospective Randomized Control Study

BACKGROUND

The aim of this study was to analyze the clinical outcomes of diagnostic transforaminal epidural injection (DTEI) in selective percutaneous endoscopic lumbar discectomy for multilevel disc herniation with monoradicular symptom.

METHODS

A prospective randomized clinical study was performed from November 2013 to January 2018. A total of 99 consecutive patients with multilevel disc herniation and monoradicular symptom were divided randomly into the DTEI (n = 48) or control (n = 51) group based on a random number list. Operation time, blood loss, intraoperative fluoroscopy, and length of hospital stay were recorded and analyzed statistically. Visual analog scale (VAS) scores, Oswestry Disability Index (ODI), and the improved MacNab standard were used to assess the clinical outcomes of the 2 groups.

RESULTS

No differences were observed between the 2 groups in aspect of baseline data. The patients of both groups had significant improvement in VAS and ODI scores compared with preoperative value. However, the postoperative VAS and ODI scores of the DTEI group were significantly lower compared with the control group. The clinical outcomes of the DTEI group according to the improved MacNab standard were significantly better than that of the control group.

CONCLUSIONS

DTEI can improve the clinical outcomes of selective percutaneous endoscopic lumbar discectomy for multilevel disc herniation with monoradicular symptom, through improving the accuracy of confirmation of responsible level.

The role of needle tip position on the accuracy of diagnostic selective nerve root blocks in spinal deformity

PURPOSE

The specificity of a selective nerve root block (SNRB) is dependant on isolating only the required nerve root whilst avoiding injectate flow to traversing nerves. Needle tip position is therefore crucial. Nerve root blocks (SNRBs) in the presence of deformity can be particularly technically challenging to perform. The aims of this study were to document the relationship of needle tip position and SNRB accuracy in patients with and without spinal deformity.

METHODS

Over an 8-month period, all SNRBs performed by one spinal surgeon were included. Patients with radiographic evidence of spinal deformity were analysed separately and their lumbar deformity graded using the Schwab grading system. Needle tip position in relation to the superior pedicle and flow of contrast was documented.

RESULTS

76 patients received 85 injections without deformity, 26 patients with deformity underwent 30 SNRBs. In the normal spinal alignment group, there was on overall accuracy of 70.1% regardless of needle tip position, which improved to 91.8% for a lateral needle tip position (P < 0.001). In patients with deformity, the overall accuracy was significantly lower irrespective of needle tip position 36 versus 70%, respectively (P < 0.0019).

CONCLUSIONS

Selective nerve root blocks are accurate in patients without deformity where a needle tip placement lateral to the middle third of the pedicle is achieved. The presence of spinal deformity significantly reduces the accuracy of SNRBs with a higher chance of epidural infiltration.

Factors that affect the efficacy of fluoroscopically guided selective spinal nerve root block in the treatment of radicular pain: a prospective cohort study

AIM

The fluoroscopically guided selective nerve root block (SNRB) is being used increasingly as a therapy for radicular pain as well as a diagnostic tool. However, studies and the literature reviews have yet to reach a definite conclusion on the efficacy in this setting. Our aim was to prospectively investigate factors that may affect the success of this procedure.

MATERIALS AND METHODS

A total of 301 treatment episodes with 283 patients were assessed over 25 months by patient questionnaire over a 7-day period. Changes in analgesic benefit over time, by operating consultant, referring specialty, spinal level, and the presence of periprocedural symptom provocation were evaluated. Statistical analysis was performed by using the χ(2) test, Wilcoxon test, and Kruskal-Wallis rank sum test, and the asymptotic marginal-homogeneity test. P < .05 was considered significant.

RESULTS

There was a statistically significant increase in pain relief over the 7 days after the procedure. Pain provocation during the procedure did not improve analgesic success. Cervical, lumbar, and sacral level procedures were equally efficacious. The specialist who referred the patient and the use of contrast to verify needle position during the procedure also did not affect the analgesic outcome. Overall, 69.1% of patients experienced some pain relief by day 7.

CONCLUSION

Analgesic success rates of selective nerve root blocks did not vary with spinal level, or use of contrast or periprocedural replication of symptoms, when using fluoroscopic guidance. Patients may expect a continued significant improvement in their symptoms for at least a week after the procedure.

Clinical outcome of nonoperative treatment for lumbar spinal stenosis, and predictive factors relating to prognosis, in a 5-year minimum follow-up

STUDY DESIGN

A prospective long-term follow-up study of nonoperative treatment for lumbar spinal stenosis (LSS) and multivariable analysis of the prognosis.

OBJECTIVES

To clarify the outcomes of nonoperative treatment for LSS over a long-term follow-up, and to extrapolate factors relating to the prognosis of treatment.

SUMMARY OF BACKGROUND DATA

The indicators of treatment for LSS remain controversial, and few reports have evaluated the prognosis of its nonoperative treatment, or extrapolated the factors that aid prognosis.

METHODS

One hundred twenty patients who received inpatient nonoperative treatment were followed up for 5 years or longer. Patients' nerve involvement and myelographic findings were classified, and the disturbance level of activities of daily living (ADL) at final follow-up was graded. The association between patients' age and sex, classification of nerve involvement and myelographic findings, recovery rate by initial nonoperative treatment, presence or absence of degenerative spondylolisthesis/scoliosis, and disturbance level of ADL were evaluated statistically to extrapolate prognostic factors.

RESULTS

In all, 52.5% of patients showed no hindrance to ADL at follow-up. Patients who were classified as radicular type, or responded well to initial nonoperative treatment, exhibited statistically better results than did other patients. In contrast, accompanying degenerative scoliosis tended to be related to a poorer prognosis.

CONCLUSION

The current study demonstrated the long-term follow-up outcome of nonoperative treatment for LSS. Important factors relating to the prognosis were demonstrated. These factors could aid the decision-making process for treatment of LSS patients.

Value of diagnostic lumbar selective nerve root block: a prospective controlled study

BACKGROUND AND PURPOSE

Although diagnostic lumbar selective nerve root blocks are often used to confirm the pain-generating nerve root level, the reported accuracy of these blocks has been variable and their usefulness is controversial. The purpose of this study was to evaluate the accuracy of diagnostic lumbar selective nerve root blocks to analyze potential causes of false results in a prospective, controlled, single-blinded manner.

MATERIALS AND METHODS

A total of 105 block anesthetics were performed under fluoroscopic guidance in 47 consecutive patients with pure radiculopathy from a single confirmed level: 47 blocks were performed at the symptomatic level, and 58 were performed at the adjacent asymptomatic "control" level. Contrast and local anesthetics were injected, and spot radiographs were taken in all cases. We calculated the diagnostic value of the block anesthetics using concordance with the injected level. We analyzed the potential causes of false results using spot radiographs.

RESULTS

On the basis of a definition of a positive block as 70% pain relief, determined by receiver-operator characteristic (ROC) analysis, diagnostic lumbar selective nerve root block anesthetics had a sensitivity of 57%, a specificity of 86%, an accuracy of 73%, a positive predictive value of 77%, and a negative predictive value of 71%. False-negatives were due to the following causes identifiable on spot radiographs: insufficient infiltration, insufficient passage of the injectate, and intraepineural injections. On the other hand, false-positives resulted from overflow of the injectate from the injected asymptomatic level into either the epidural space or symptomatic level.

CONCLUSION

The accuracy of diagnostic lumbar selective nerve root blocks is only moderate. To improve the accuracy, great care should be taken to avoid inadequate blocks and overflow, and to precisely interpret spot radiographs.

Cerebellar and brainstem infarction as a complication of CT-guided transforaminal cervical nerve root block

A 60-year-old man with a 4-year history of intractable neck pain and radicular pain in the C5 nerve root distribution presented to our department for a CT-guided transforaminal left C5 nerve root block. He had had a similar procedure on the right 2 months previously, and had significant improvement of his symptoms with considerable pain relief. On this occasion he was again accepted for the procedure after the risks and potential complications had been explained. Under CT guidance, a 25G spinal needle was introduced and after confirmation of the position of the needle, steroid was injected. Immediately the patient became unresponsive, and later developed a MR-proven infarct affecting the left vertebral artery (VA) territory. This is the first report of a major complication of a cervical root injection under CT guidance reported in the literature. We present this case report and the literature review of the potential complications of this procedure.

[Facet blockade, peridural and periradicular pain therapy]

More than 80% of vertebrogenic lumbar pain is unspecific and can only be attributed to a specific anatomic structure with difficulty. The pain can emanate from the intervertebral discs, intervertebral and sacroiliac (SI) joints, musculature, and ligaments. In a maximum of 7% of cases, the pain is radicular (4% due to intervertebral discs and 3% caused by stenoses). In 7-15% of cases, the pain's origin is located in the region of the vertebral joints and in up to 15% in the region of the SI joint. Although the overwhelming majority of pain has no clear structural cause, infiltrations of medications and nerve blockades are frequently employed. The efficacy of these procedures has however not been verified in controlled studies with the exception of epidural injection of corticosteroids for radicular pain. Epidural and epiradicular application of corticosteroids appear to be effective for radicular pain, at least on a short-term basis, although controlled studies have yielded controversial results. The difficulty lies partly in the exact placement at the affected root for applying the medication. This is hardly possible with a caudal injection, while with a lumbar peridural injection and periradicular injections it is only possible under X-ray control or even better CT guidance.

The value of nerve root infiltration for leg pain when used with a nerve stimulator

Randomized comparative study of the efficacy of nerve root infiltration (NRI) guided by neurostimulator to find the value of nerve stimulators in nerve root infiltration was undertaken. The response to nerve root infiltration using local anaesthetics and steroid is unpredictable, partly because the exact nerve root giving rise to pain may not be truly infiltrated. The nerve stimulator is advocated to identify the nerve root of concern prior to infiltration. The current study assessed the results of NRI with and without the nerve stimulator. Ninety-six patients with leg pain awaiting selective nerve root infiltration using long acting local aesthetic, were prospectively randomized into two groups, in the first one, the nerve root block was carried out without nerve stimulator (n = 39) and in the second group the block was carried out with the guidance of a nerve root stimulator (n = 57). Seventy-seven of the patients who had lateral canal stenosis (a total 81) responded to NRI; within this group nerve stimulator was used for 50 patients. Nerve root infiltration was used to relieve post-discetomy leg pain (ten), post-disc prolapse (four) and in one patient post-nucleotomy leg pain. Overall 89% of the patients were responders of NRI. Responders of around 65% had the NRI performed with the aid of stimulator. The response rate to pain was 96% when NRI was guided by a neurostimulator and 79% when no neurostimulator was used. When responded there was no significant statistical difference using the Oswestry disability score between both groups. After excluding disc bulge in patients who respond partially to NRI, it is worthwhile repeating the injection. There was a significant difference in response rate when NRI was done under guidance of a nerve stimulator, the stimulator is safe to use and increases the specificity of the block.

Selective Nerve Root Injections Can Predict Surgical Outcome For Lumbar and Cervical Radiculopathy

OBJECTIVE

Diagnostic selective nerve root injection (SNI) results were analyzed in 101 patients who underwent lumbar or cervical decompression for radiculopathy and compared to surgical outcome 1 year postoperatively. A comparison of surgical outcomes was also examined between magnetic resonance imaging (MRI) and SNI results.

RESULTS

Of the 101 patients, 91 (90%) had positive and 10 had negative SNI results at the level operated. Ninety-one percent of the patients with a positive SNI had good surgical outcomes, whereas 60% of the patients with a negative SNI had good outcomes. Of the patients with a positive MRI result, 87% had good surgical outcomes, whereas a similar percentage of the patients with a negative MRI (85%) had good surgical outcomes. When findings between SNI and MRI differed (n = 20), surgery at a level consistent with the SNI was more strongly associated with a good surgical outcome. Of the patients with a poor surgical outcome, surgery was most often performed at a level inconsistent with the SNI finding.

CONCLUSIONS

Our study found that a diagnostic SNI can safely and accurately discern the presence or absence of cervical or lumbar radiculopathy. The diagnostic SNI can persuade surgeons from operating on an initially suspicious, but incorrect, level of radiculopathy. In cases where MRI findings are equivocal, multilevel, and/or do not agree with the patient's symptoms, the result of a negative diagnostic SNI (ie, lack of presence of radiculopathy) becomes superior in predicting the absence of an offending lesion.

The prognosis of conservative treatments for lumbar spinal stenosis: analysis of patients over 70 years of age

STUDY DESIGN

A prospective study.

OBJECTIVES

To identify outcomes of aged patients with lumbar spinal stenosis (LSS) treated conservatively and to examine factors that control the prognosis.

SUMMARY AND BACKGROUND DATA

There have been no reports evaluating the outcomes of conservative treatments for elderly LSS patients.

METHODS

A total of 89 patients, 70 years of age and older, who underwent in-hospital conservative treatment were included. The Japanese Orthopedic Association's score (JOA score) and the disturbance level of activities of daily living (ADL) were used for evaluation. Nerve involvement was classified into radicular, cauda equina, and mixed type. Myelographic findings were classified into central defect with or without block and root defect. Associations between disturbance level of ADL, nerve involvement, and myelographic classifications were investigated.

RESULTS

The mean JOA score increased from 11.1 points at admission to 15.9 points at discharge, with 14.3 points maintained at the follow-up; 48.8% of radicular type showed no obstacle in ADL at the follow-up compared with 33.3% of the other types; 13.3% of central defect with block showed no obstacle in ADL compared with 47.8% of the other types with significant difference.

CONCLUSION

The prognosis of conservative treatment for aged LSS was relatively good. Radicular type may be a candidate for conservative treatment. However, patients with complete block in the myelogram may not respond favorably to conservative treatment.

Cervical Nerve Root Blocks: Indications and Role of MR Imaging

PURPOSE

To examine whether magnetic resonance (MR) imaging findings of the cervical spine can predict pain relief after selective computed tomography (CT)-guided nerve root block and thus assist in the appropriate selection of patients who are suitable for this procedure.

MATERIALS AND METHODS

Sixty consecutive patients with cervical radicular pain were examined with MR imaging and then treated with CT-guided cervical nerve root blocks (CNRBs). Various MR imaging findings were assessed and compared in terms of associated pain relief after CNRB. Pain relief was graded (0%-100%) by using a visual analogue scale (VAS). The relationship between MR imaging findings and level of pain relief was tested by using Mann-Whitney U and Kruskal-Wallis tests.

RESULTS

The mean percentage of pain reduction at VAS grading was 46%. There was a significant relationship between pain relief level and both location of disk herniation (mean pain reductions of 41% at median or mediolateral locations and 64% at foraminal locations, P =.034) and location of nerve root compromise (mean pain reductions of 19% at intraspinal, 45% at foraminal entrance, and 58% at foraminal locations; P =.019). There was an inverse relationship between pain relief level and absence or presence of spinal canal stenosis (mean pain reductions of 29% when stenosis present and 53% when stenosis absent, P =.013). Other parameters were not significantly related to pain relief.

CONCLUSION

MR imaging of the cervical spine assists in the appropriate selection of patients suitable for CNRB. Patients with foraminal disk herniation, foraminal nerve root compromise, and no spinal canal stenosis appear to have the greatest pain relief after this procedure.

[Diagnostics and minimally invasive therapy for chronic low back pain]

Chronic low back pain is one of the most frequent causes for seeking medical help in Germany. Many factors play a causal role in its pathogenesis. This is where the dilemma resides in narrowing down the diagnosis and deciding on subsequent therapeutic intervention. There is overall agreement on the concept of when it is expedient to initiate further diagnostic measures. With the exception of clear pathomorphological findings and the presence of cardinal symptoms or warning signs, so-called "red flags", primary back pain should not be subjected to any specific diagnostic tests and therapy during the first 3 months. We present well-established techniques for blockade, discography, and minimally invasive treatment options such as cryotherapy, procedures for thermal ablation, and intradiscal electrotherapy. Vertebroplasty, currently a frequently applied method, is also included in the discussion of minimally invasive treatment for chronic low back pain.

Selective nerve root blocks

Selective nerve root blocks are valuable diagnostic and therapeutic procedures in patients with radicular symptoms. Understanding the anatomy, benefits, and risks, as well as precise needle placement, are important factors in performing successful nerve root blocks. The techniques we describe come from our training and ongoing experience. There are other acceptable methods as well.

Image-guided spinal injection for diagnosis and therapy

Over the past decade, major advances have been made in our ability to identify a putative cause of patients' spinal pain using image-guided injection techniques. These techniques might also provide a means of temporarily relieving patients' pain and facilitating increased mobility. This article aims to review the rationale for and the techniques of the more commonly used spinal injection techniques.

A novel technique for delivery of epidural steroids and diagnosing the level of nerve root pathology

Transforaminal epidural steroids are a commonly used technique for diagnosis and treatment of nerve root irritation secondary to herniated disc material. The recent reported occurrences of severe complications using the transforaminal technique have led to the search for a novel alternative that is both a safe and accurate method of steroid delivery. The technique described offers improved safety and diagnostic accuracy over traditional transforaminal steroid injections.

General principles of diagnostic testing as related to painful lumbar spine disorders: a critical appraisal of current diagnostic techniques

STUDY DESIGN

The literature on diagnostic tests available to the spine clinician for the evaluation of chronic low back pain was reviewed.

OBJECTIVES

To review critically the available information and data on invasive diagnostic tests used for evaluation of chronic low back pain.

SUMMARY OF BACKGROUND INFORMATION

Numerous published studies have described the technique and clinical results of diagnostic blocks for chronic low back pain. There are various methodologies, but most lack of an adequate "gold standard" with which to compare the results of the diagnostic test.

METHODS

The available published studies of diagnostic tests commonly used in the evaluation of chronic low back pain were reviewed, with a focus on invasive techniques. The techniques were evaluated on the basis of the data available to support the conclusions that could be drawn for each of these techniques. The principles of diagnostic testing, including specificity and sensitivity, were reviewed and applied in the context of the data available for each of these invasive tests.

RESULTS

The essential features the clinician seeks in a diagnostic test are accuracy, safety, and reproducibility. It is essential to have a gold standard with which to compare the accuracy of a given diagnostic test. There is no completely reliable gold standard with which to compare a diagnostic test (or injection) when the absence of pain is the end point. The clinical setting in which the test is used directly affects the test results. The prevalence of the disease therefore affects the meaningfulness of the test results. Imaging studies have their greatest value in the exclusion of other conditions. These studies alone were not adequate for predicting the patients who would respond to controlled diagnostic blocks of the facet joint. Facet joint diagnostic blockade probably is most accurately performed by median nerve branch block. The greatest specificity for a positive response to a facet denervation procedure is achieved when the diagnosis is established via highly controlled anesthetic blocks. Over the past few decades, the sacroiliac joint has received varying degrees of interest as an important pain generator of low back pain. Despite testimonials to the contrary, no diagnostic physical examination has correlated with sufficient specificity to diagnose this condition reliably from a clinical standpoint. Lumbar discography has been one of the single most controversial subjects in the management of degenerative, painful lumbar spine conditions. The specificity and sensitivity are high for the diagnosis of disc degeneration. The question that revolves around discography concerns the accuracy of this test for the diagnosis of discogenic pain. An integral part of the problem is the lack of an adequate gold standard. In a comparison of nerve root blockade, sciatic nerve block, posterior ramus block, and subcutaneous injection in a cohort of patients with sciatica, the sensitivity of nerve root block was very high, with only a moderate level of specificity. In the case of diagnostic selective nerve blocks used for evaluation of complex or protean nerve compression, surgical confirmation and clinical results should be a reliable gold standard. Conflicting results have been presented depending on the target lesion and method of study.

CONCLUSIONS

There are inherent limitations in the accuracy of all diagnostic tests. The tests used to diagnose the source of a patient's chronic low back pain require accurate determination of the abolition or reproduction of the patient's painful symptoms.

Diagnostic selective nerve root blocks: indications and usefulness

Diagnostic SNRIs are a useful tool in the diagnosis of radicular pain in atypical presentations. Diagnostic SNRI is indicated in the following circumstances: (1) for atypical extremity pain; (2) when imaging studies and clinical presentation do not correlate; (3) when electromyography and MRI are not corroborative or are equivocal; (4) for anomalous innervations, such [figure: see text] as conjoint nerve roots or furcal nerves [71]; (5) for failed back surgery syndrome with atypical extremity pain; and (6) for transitional vertebrae. Patients should have demonstrated a failure to improve with less invasive treatment. In these patients, a diagnostic SNRI may localize the pain to a specific spinal nerve. It must be emphasized that the diagnostic SNRI only determines if pain is emanating from a specific nerve root or spinal nerve. A diagnostic SNRI does not determine what has caused the nerve root or spinal nerve pain, nor does it provide prognostic information. The etiology of the nerve root pain, mechanism of injury, underlying anatomy, duration of symptoms, comorbidities, patient desire, physician skill, and a host of other factors determine the appropriate treatment and prognosis.

Radiofrequency facet joint denervation in the treatment of low back pain: a placebo-controlled clinical trial to assess efficacy

STUDY DESIGN

A prospective double-blind randomized controlled trial was performed.

OBJECTIVE

To assess the efficacy of percutaneous radiofrequency articular facet denervation for low back pain.

SUMMARY OF BACKGROUND DATA

Uncontrolled observational studies in patients with low back pain have reported some benefits from the use of facet joint radiofrequency denervation. Because the efficacy of percutaneous radiofrequency had not been clearly shown in previous studies, a randomized controlled trial was conducted to assess the efficacy of the technique for improving functional disabilities and reduce pain.

METHODS

For this study, 70 patients with low back pain lasting of more than 3 months duration and a good response after intraarticular facet injections under fluoroscopy were assigned randomly to receive percutaneous radiofrequency articular facet denervation under fluoroscopic guidance or the same procedure without effective denervation (sham therapy). The primary outcomes were functional disabilities, as assessed by the Oswestry and Roland-Morris scales, and pain indicated on a visual analog scale. Secondary outcomes included spinal mobility and strength.

RESULTS

At 4 weeks, the Roland-Morris score had improved by a mean of 8.4% in the neurotomy group and 2.2% in the placebo group, showing a treatment effect of 6.2% (P = 0.05). At 4 weeks, no significant treatment effect was reflected in the Oswestry score (0.6% change) or the visual analog pain score (4.2% change). At 12 weeks, neither functional disability, as assessed by the Roland-Morris scale (2.6% change) and Oswestry scale (1.9% change), nor the pain level, as assessed by the visual analog scale (-7.6% change), showed any treatment effect.

CONCLUSIONS

Although radiofrequency facet joint denervation may provide some short-term improvement in functional disability among patients with chronic low back pain, the efficacy of this treatment has not been established.

The imaging of lumbar spinal stenosis

Lumbar spinal stenosis (LSS) is a relatively common condition of varied aetiology which results in chronic compression of the cauda equina. It becomes clinically relevant when giving rise to symptoms of neurogenic claudication or leg pain. Lumbar spinal stenosis can be classified based on anatomy or aetiology and the diagnosis in any single case should include a consideration of both the site and the cause. Plain radiography is of limited value. Myelography with erect lateral flexion/extension views will demonstrate the dynamic component of the stenosis which cannot be appreciated on plain computed tomography (CT) or magnetic resonance imaging (MRI). Therefore, in patients with a good history of symptomatic LSS, and a borderline stenosis on MRI, CT myelography is recommended as the definitive pre-operative imaging investigation.

Nonoperative treatment of low back pain

Low back pain is a common problem with substantial social and economic issues. Physicians continue to have difficulty managing this condition despite an increased awareness of its magnitude. In addition, there is a misperception about the outcome of patients affected with low back pain; most continue to suffer from pain. We present a nonoperative approach and review various diagnostic and treatment strategies with respect to both scientific and clinical merit. Although many treatment strategies have not been well proved in the scientific literature, thoughtful review of the available information provides a basis for the use of these treatment methods in the patient with refractory pain. This approach can be used in conjunction with existing information to assist clinicians in the management of patients with acute low back pain.