Side of symptomatic annular tear and site of low back pain: is there a correlation?

Longitudinal assessment of annular fissures of the cervical spine: overlooked and static

Background

Cervical annular fissures (AFs) have not been studied specifically as to their prevalence, imaging features, and persistence over time. We sought to determine the prevalence and natural history of cervical AFs. We hypothesized that these are static lesions that are not prevalent in the population.

Methods

This was a cross-sectional retrospective study of cervical MRI examinations performed between 2011-2021. We retrospectively reviewed the studies of 115 consecutive patients (63 female, 52 male) who had 2 or more MRI studies of the cervical spine to identify (1) imaging features of cervical AFs on various pulse sequences, (2) the concurrence of disc bulges/herniations, (3) changes in those imaging findings over time (mean follow-up 39.3 months) and (4) rate at which cervical AFs were mentioned in radiology reports. 620 initial and follow-up studies were reviewed.

Results

50/115 (43.5%) patients had cervical AFs; 21 patients had a single AF and 29 patients had multi-level AFs (total 109 AFs). The most common levels affected were C4-C5 (28%, n = 31) and C5-C6 (27%, n = 30). All cervical AFs were hyperintense on T2WI and, over time, 95% (n = 104/109) of the AFs remained hyperintense; 22% (n = 25) showed less hyperintensity, 10% (n = 11) more hyperintensity, and 60% (n = 66) the same hyperintensity. 5 AFs (4%) resolved completely. Only 2 (8%) of 25 cervical AFs enhanced with gadolinium. The rate of concomitant disc bulges and herniations was 71% (n = 78) and 22% (n = 24) respectively. The presence of cervical AFs did not increase the risk of progression to bulges or herniations. None of the cervical AFs were mentioned in the radiology reports.

Conclusions

Cervical AFs occurred in 43.5% of patients but were rarely reported. They usually remained bright on T2W but their brightness could vary over time. Cervical AFs were often associated with disc bulges/herniations and enhanced less frequently (8%) than lumbar disk AFs.

Does the location of low back pain predict its source?

OBJECTIVE

To evaluate the predictive utility of the pattern of low back pain (LBP) in detecting the source of LBP as internal disk disruption (IDD), facet joint pain (FJP), or sacroiliac joint pain (SIJP).

DESIGN

Retrospective chart review.

SETTING

University spine center.

PATIENT SAMPLE

A total of 170 cases from 156 patients presenting with LBP whose low back disorder was definitively diagnosed. The mean age was 54.4 years (SD, 16.2) and median duration of LBP was 12 months (interquartile ranges, 6-32).

METHODS

Charts of consecutive LBP patients who underwent definitive diagnostic spinal procedures including provocation diskography, facet joint blocks, and sacroiliac joint blocks were retrospectively reviewed. Each patient with LBP was queried as to the exact location of their LBP: midline, defined as in-line with the spinous processes, and/or paramidline, defined as lateral to 1 fingerbreadth adjacent to the midline.

OUTCOME MEASURES

In patients with a definitive diagnosis for the source of LBP, the proportion of each diagnosed source of pain was calculated. χ(2) tests were used to identify differences in the percentages of midline and paramidline LBP among the groups of patients testing positive for IDD, FJP, or SIJP. Diagnostic measures of sensitivity, specificity, positive and negative predictive values, diagnostic accuracy, and likelihood ratios of positive and negative tests using the presence/absence of midline and paramidline pain for the diagnosis of IDD, FJP, and SIJP were estimated.

RESULTS

With cases of IDD, significantly greater percentages of patients reported midline LBP (95.8%; χ(2) = 101.4, df = 2, P < .0001) as compared with cases of FJP (15.4%) or SIJP (12.9%). In cases of IDD, significantly lower percentages of patients reported paramidline pain (67.3%; χ(2) = 16.1, df = 2, P = .0003) as compared with cases of FJP (95.0%) or SIJ (96.0%). In cases of IDD, significantly greater percentages of patients reported midline LBP (95.8%; χ(2) = 101.4, df = 2, P < .0001) as compared with cases of FJP (15.4%) or SIJP (12.9%). The specificity of midline LBP for IDD, FJP, and SIJP was 74.8% (95% CI = 65.0%-82.9%), 28.0% (20.1%-37.0%), and 36.0% (28.0%-44.5%), respectively. The negative predictive value of paramidline LBP for IDD, FJP, and SIJP was 29.2% (95% CI = 12.6%-51.1%), 91.7% (73.0%-99.0%), and 95.8% (78.9%-99.9%). The diagnostic accuracy of midline LBP for IDD, FJP, and SIJP was 83.5%, 24.1%, and 31.8%, respectively.

CONCLUSIONS

The presence of midline LBP increases the probability of lumbar IDD and reduces the probability of symptomatic FJ and SIJ dysfunction. The presence of isolated paramidline LBP increases the probability of symptomatic FJ or SIJ but mildly reduces the likelihood of lumbar IDD.

Clinical and radiological findings of discogenic low back pain confirmed by automated pressure-controlled discography

OBJECTIVE

Few studies on the clinical spectrum of automated pressure-controlled discography (APCD)-defined positive discs have been reported to date. Thus, the present study was undertaken to analyze clinical parameters critical for diagnosis of discogenic pain and to correlate imaging findings with intradiscal pressures and pain responses in patients with APCD-positive discs.

METHODS

Twenty-three patients who showed APCD-positive discs were selected for analysis. CT discogram findings and the degrees of nuclear degeneration seen on MRI were analyzed in comparison to changes of intradiscal pressure that provoked pain responses; and clinical pain patterns and dynamic factors were evaluated in relation to pain provocation.

RESULTS

Low back pain (LBP), usually centralized, with diffuse leg pain was the most frequently reported pattern of pain in these patients. Overall, LBP was most commonly induced by sitting posture, however, standing was highly correlated with L5/S1 disc lesions (p < 0.01). MRI abnormalities were statistically correlated with grading of CT discogram results (p < 0.05); with most pain response observed in CT discogram Grades 3 and 4. Pain-provoking pressure was not statistically correlated with MRI grading. However, it was higher in Grade 3 than Grade 4.

CONCLUSION

APCD-positive discs were demonstrated in patients reporting centralized low back pain with diffuse leg pain, aggravated by sitting and standing. MRI was helpful to assess the degree of nuclear degeneration, yet it could not guarantee exact localization of the painful discs. APCD was considered to be more useful than conventional discography for diagnosis of discogenic pain.

Burned-out discs stop hurting: fact or fiction?

STUDY DESIGN

Cross-sectional study of a general-population sample.

OBJECTIVE

The aim was to test the hypothesis that moderate disc degeneration (DD) is stronger associated with low back pain (LBP) than severe degeneration, and also to identify a possible dose-response relationship between numbers of degenerated discs and LBP.

SUMMARY OF BACKGROUND DATA

Among many clinicians there has been a belief that DD initially causes pain because of the penetration of fluid nuclear material through annular fissures, and that pain eventually resolves as the nucleus becomes fibrotic and can no longer penetrate the fissures.

METHODS

From a population-based cohort of 412 individuals, all aged 40, three groups were created for a primary analysis: those with exclusively normal discs (white nuclei on a T2-weighted MRI), those with moderate DD (grey) + normal, and those with severely degenerated (black) + normal discs. The number of individuals reporting LBP during the past year (the most relevant for chronic/intermittent pain) and the past month were separately related to DD. Second, a possible dose-response in terms of numbers of abnormal discs was analyzed.

RESULTS

The percentage of people with LBP was virtually not influenced by grey discs, where the fraction with pain during the past year was close to 69% irrespective of the presence or number of grey discs. Black discs, however, increased the corresponding fraction from 60%, if no black discs, to 86% for those with 2 (odds ratio of 2 per number of black disc). The risk for LBP during the past year attributed to black discs was 11%.

CONCLUSION

The data could not support the hypothesis that severely degenerated discs are "burned out" and become less painful. People with black discs had a higher prevalence of LBP compared to those with grey or normal discs, the latter 2 being equally often painful.

Evidence-informed management of chronic low back pain with epidural steroid injections

The management of chronic low back pain (CLBP) has proven very challenging in North America, as evidenced by its mounting socioeconomic burden. Choosing amongst available nonsurgical therapies can be overwhelming for many stakeholders, including patients, health providers, policy makers, and third-party payers. Although all parties share a common goal and wish to use limited health-care resources to support interventions most likely to result in clinically meaningful improvements, there is often uncertainty about the most appropriate intervention for a particular patient. To help understand and evaluate the various commonly used nonsurgical approaches to chronic low back pain, the North American Spine Society has sponsored this special focus issue of The Spine Journal, titled Evidence-Informed Management of Chronic Low Back Pain Without Surgery. Articles in this special focus issue were contributed by leading spine practitioners and researchers, who were invited to summarize the best available evidence for a particular intervention and encouraged to make this information accessible to nonexperts. Each of the articles contains five sections (description, theory, evidence of efficacy, harms, and summary) with common subheadings to facilitate comparison across the 24 different interventions profiled in this special focus issue, blending narrative and systematic review methodology as deemed appropriate by the authors. It is hoped that articles in this special focus issue will be informative and aid in decision making for the many stakeholders evaluating nonsurgical interventions for CLBP.

Diagnosis and minimally invasive treatment of lumbar discogenic pain--a review of the literature

Diagnosis and treatment of lumbar discogenic pain due to internal disc disruption (IDD) remains a challenge. It accounts for 39% of patients with low back pain. The mechanism of discogenic pain remains unclear and its clinical presentation is atypical. Magnetic resonance imaging (MRI) can find high-intensity zone as an indirect indication of IDD. However, relative low sensitivity (26.7% to 59%) and high false-positive (24%) and false-negative (38%) rates reduce the value of MRI in screening for the existence of painful IDD. Provocative discography can provide unique information about the pain source and the morphology of the disc. It may also provide information for selecting appropriate treatment for the painful annular tear. Adjunctive therapies, including nonsteroidal anti-inflammatory drugs, physical therapy, rehabilitation, antidepressants, antiepileptics, and acupuncture, have been used for low back pain. The value of these treatments for discogenic pain is yet to be established. Intradiscal steroid injection has not been proved to provide long-term benefits. Intradiscal electrothermal therapy may offer some pain relief for a group of well-selected patients. No benefits have been found for the intradiscal radiofrequency thermocoagulation. A block in the ramus communicans may interfere with the transition of painful information from the discs to the central nervous system. Disc cell transplantation is in the experimental stage. It has the potential to become a useful tool for the prevention and treatment of discogenic pain. Minimally invasive treatments provide alternatives for discogenic pain with the appeal of cost-effectiveness and, possibly, less long-term side effects. However, the value of most of these therapies is yet to be established. More basic science and clinical studies are needed to improve the clinical efficacy of minimally invasive treatments.

Discogenic lumbar pain: association with MR imaging and CT discography

OBJECTIVE

To correlate MR and CT discography findings with pain response at provocative discography in patients with discogenic back pain.

MATERIALS AND METHODS

Forty-seven patients aged 25-54 years who underwent MR imaging and subsequent CT discography (97 discs) were included in this study. MR images were retrospectively evaluated regarding disc degeneration, endplate abnormalities, facet joint osteoarthritis, and high intensity zone. During discography concordant pain was regarded as positive, whereas discordant pain and no pain were regarded as negative. MR and CT discographic findings were analyzed on the base of concordant pain using the Chi-square test.

RESULTS

: Concordant pain was significantly common in the following (P < 0.05): grade 4 or 5 disc degeneration [88% (30/34) in concordant pain versus 48% (30/63) in discordant pain and no pain], high intensity zone [56% (19/34) versus 30% (19/63)], combination of above two findings [53% (18/34) versus 25% (16/63)], fissured and ruptured disc at discogram [94% (32/34) versus 57% (36/63)], and contrast beyond inner annulus at CT discogram [97% (33/34) versus 57% (36/63)].

CONCLUSION

Typical MR findings with concordant pain at discography include grade 4 or 5 disc degeneration and presence of a high intensity zone. Typical CT discography findings with concordant pain were fissured/ruptured discs and contrast extending into/beyond the outer annulus on CT.

The Relation Between Annular Disruption on Computed Tomography Scan and Pressure-Controlled Diskography

OBJECTIVE

To analyze the relation between annular disruption determined by computed tomography (CT) scan and diskographic findings using pressure-controlled manometric diskography.

DESIGN

Cross-sectional using prospectively gathered data.

SETTING

Ambulatory spine intervention unit.

SPECIMENS

Two hundred seventy-nine disks from 86 patients (55 men, 31 women) who were referred for diskography of suspected chronic diskogenic low back pain.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The grade of annular disruption was rated using CT diskography and fluoroscopic imaging as follows: 0 (no disruption); 1 (extension into the inner third of the annulus); 2 (extension into the middle third of the annulus); 3 (extension into the outer third of the annulus); 4 (circumferential extension with a >30 degrees arc at the disk center); and 5 (contrast media leakage into the outer space). Diskography was performed via a pressure-controlled manometric technique using an injection rate of .05 mL/s and a restricted total volume of 3.5 mL. Pain was rated on a 0 to 10 numeric rating scale (NRS). Criteria for symptomatic disks included provocation of patient concordant pain (NRS score, > or =6/10) at 50psi or less above opening pressure, with 3.5 mL or less of total volume. Symptomatic disks were classified as "low pressure sensitive" or "high pressure sensitive" based on the pressure level that evoked pain. Disks classified as low pressure sensitive required an NRS score of 6 out of 10 or higher at 15 psi or less above opening pressure. Disks classified as high pressure sensitive required an NRS score of 6 out of 10 or higher at pressures within a range of 15 to 50 psi.

RESULTS

The numbers of disks at each annular disruption grade were 19 (6.8%) at grade 0, 29 (10.4%) at grade 1, 35 (12.5%) at grade 2, 42 (15.1%) at grade 3, 69 (24.7%) at grade 4, and 85 (30.5%) at grade 5. A total of 93 disks met the criteria for a symptomatic disk. The extent of annular disruption and the rate of symptomatic disks correlated significantly (P<.001). The highest symptomatic disk rate was observed in grade 4 disks. Of 93 symptomatic disks, 88 (94.6%) showed annular disruption of grade 3 or greater. Disks with grades 0 to 2 and grades 3 to 5 annular disruption differed significantly when the mean NRS relative to intradiskal pressure was compared (P<.001). Comparing the disk type of symptomatic disks at each annular disruption grade, there was a decreasing trend of low pressure sensitive disks relative to the extent of annular disruption (62.5% at grade 3, 39.4% at grade 4, 34.2% at grade 5).

CONCLUSIONS

Annular disruption reaching the outer annulus fibrosus is a key factor in pain generation. Disk morphology, including annular disruptions extending beyond the outer annulus, may permit increased diskography specificity.

Lumbar discography: current concepts and controversies

Lumbar provocation discography is an invasive diagnostic procedure to identify pain originating from within the lumbar discs. Specific morphological changes within the disc, classified as radial fissures, can be imaged following the injection of radiopaque contrast into the nucleus pulposus. The reproduction of concordant low back and/or referred somatic pain to the lower extremity under controlled conditions and the demonstration of annular radial tears are part of a spectrum of internal disc disruption that is separate from disc degeneration. A review of the validity and technique of lumbar discography as well as recently described causes of false positive responses are presented.

Intradiscal Electrothermal Annuloplasty

Low back pain is a common problem, and although the majority of cases of low back pain resolve, a subset of patients will continue to have intractable pain despite appropriate conservative treatments. Intradiscal electrothermal annuloplasty is a minimally invasive spinal procedure that has been proposed to treat provocation discography-proven internal disk disruption syndrome. The early uncontrolled and nonrandomized intradiscal electrothermal annuloplasty literature suggests it may provide some relief in a small proportion of strictly defined patients; however, more recent randomized, placebo-controlled trials have not substantiated these initial findings. This article will review the published literature, indications, contraindications, safety, and efficacy of the intradiscal electrothermal annuloplasty procedure for the treatment of chronic, intractable, axial back pain.

Centralization as a predictor of provocation discography results in chronic low back pain, and the influence of disability and distress on diagnostic power

BACKGROUND CONTEXT

The "centralization phenomenon" (CP) is the progressive retreat of referred pain towards the spinal midline in response to repeated movement testing (a McKenzie evaluation). A previous study suggested that it may have utility in the clinical diagnosis of discogenic pain and may assist patient selection for discography and specific treatments for disc pain.

PURPOSE

Estimation of the diagnostic predictive power of centralization and the influence of disability and patient distress on diagnostic performance, using provocation discography as a criterion standard for diagnosis, in chronic low back pain patients.

STUDY DESIGN/SETTING

This study was a prospective, blinded, concurrent, reference standard-related validity design carried out in a private radiology clinic specializing in diagnosis of chronic spinal pain.

PATIENT SAMPLE

Consecutive patients with persistent low back pain were referred to the study clinic by orthopedists and other medical specialists for interventional radiological diagnostic procedures. Patients were typically disabled and displayed high levels of psychosocial distress. The sample included patients with previous lumbar surgery, and most had unsuccessful conservative therapies previously.

DIAGNOSIS

results of provocation discography.

INDEX TEST

The CP. Psychometric evaluation: Roland-Morris, Zung, Modified Somatic Perception questionnaires, Distress Risk Assessment Method, and 100-mm visual analog scales for pain intensity.

METHODS

Patients received a single physical therapy examination, followed by lumbar provocation discography. Sensitivity, specificity, and likelihood ratios of the CP were estimated in the group as a whole and in subgroups defined by psychometric measures.

RESULTS

A total of 107 patients received the clinical examination and discography at two or more levels and post-discography computed tomography. Thirty-eight could not tolerate a full physical examination and were excluded from the main analysis. Disability and pain intensity ratings were high, and distress was common. Sensitivity, specificity, and positive likelihood ratios for centralization observed during repeated movement testing for pain distribution and intensity changes were 40%, 94%, and 6.9 respectively. In the presence of severe disability, sensitivity, specificity, and positive likelihood ratios were 46%, 80%, 3.2 and for distress, 45%, 89%, 4.1. In the subgroups with moderate, minimal, or no disability, sensitivity and specificity were 37%, 100% and for no or minimal distress 35%, 100%.

CONCLUSIONS

Centralization is highly specific to positive discography but specificity is reduced in the presence of severe disability or psychosocial distress.

Comparison of discographic findings in asymptomatic subject discs and the negative discs of chronic LBP patients: can discography distinguish asymptomatic discs among morphologically abnormal discs?

BACKGROUND CONTEXT

Lumbar discography has been widely used for evaluating discogenic low back pain (LBP). Comparison of pain responses from suspected symptomatic discs with pain responses from asymptomatic negative discs is routine. However, the ability of discography to distinguish asymptomatic morphologically abnormal discs from those that are symptomatic has been understudied. In addition, the discographic characteristics of negative discs in patients with chronic discogenic LBP have not been reported. Criteria for negative morphologically abnormal discs may be valuable for excluding discs from further treatment and examination.

PURPOSE

To determine if discography can distinguish asymptomatic discs among morphologically abnormal discs in patients with suspected chronic discogenic LBP and establish the standard characteristics of negative discs.

STUDY DESIGN/SETTING

Prospective, experimental with control group.

PATIENT SAMPLE

Fifty-five discs from a control group of 16 healthy volunteers without current back pain (11 men, 5 women, 32-61 years of age, mean age: 47 years) and 282 discs from a patient group of 90 LBP patients (59 men, 31 women, 20-70 years of age, mean age: 44.7 years) were recruited.

METHODS

Discography was performed using a pressure-controlled manometric technique with an injection rate of 0.05 mL/s and a 3.5 mL restricted total volume. Concordance was rated as none/unfamiliar, or familiar. Pain was rated via a 0-10 numerical rating scale (NRS). The pressure and volume at which pain was evoked and NRS pain responses at 15, 30, and 50 psi were recorded. Annular disruption grade was rated during the procedure by computed tomography discography and fluoroscopic imaging. Negative discogram required no pain described by the participant as "familiar," with no pain responses >or=6/10 NRS at pressures <or=50 psi above opening pressure and <or=3.5 mL total injected volume. Patient discs were partitioned into two subgroups based on discographic findings: Neg-D (negative discs) and Pos-D (positive discs). Only discs with Grade 3 annular tears (Dallas Discogram Scale) were included in the study.

RESULTS

Among 55 asymptomatic control group discs, 32 (58.2%) exhibited Grade 3 annular tear. All discs in the asymptomatic control group satisfied negative response criteria. Among 282 patient group discs, 199 (70.6%) exhibited Grade 3 annular tear. Of 199 discs with Grade 3 annular tears, 104 (52.3%) satisfied negative response criteria and were categorized as the Neg-D group. The other 95 discs were categorized as a Pos-D group. Patients showed significantly lower pain tolerance relative to control subjects (p<.05). The control and Neg-D groups showed similar pressures and volumes at which pain was initially evoked. Mean control group pain scores were 0.47 NRS at 15 psi and 1.58 NRS at 50 psi. Mean Neg-D group pain scores were 0.11 NRS at 15 psi and 1.1 NRS at 50 psi. Discographic findings for the Pos-D group were significantly different from those of the control and Neg-D groups (p<.001).

CONCLUSIONS

Pain tolerance was significantly lower in patients relative to asymptomatic subjects. Negative patient discs and asymptomatic subject discs showed similar characteristics. Pressure-controlled manometric discography using strict criteria may distinguish asymptomatic discs among morphologically abnormal discs with Grade 3 annular tears in patients with suspected chronic discogenic LBP.

Guidelines for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 6: magnetic resonance imaging and discography for patient selection for lumbar fusion

Discography is an exquisitely sensitive but not specific diagnostic test for the diagnosis of discogenic low-back pain. The restriction of the definition of a positive discographic study to one that elicits concordant pain from a morphologically abnormal disc improves the definition's accuracy. Fusion surgery based on discography alone, however, is not reliably associated with clinical success. Therefore, discography is not recommended as a standalone test for treatment decisions in patients with low-back pain. Magnetic resonance imaging is a sensitive and noninvasive test for the presence of degenerative disc disease. Discography should not be attempted in patients with normal lumbar MR images. Discography appears to have a role in the evaluation of patients with low-back pain, but it is best limited to the evaluation of abnormal interspaces identified on MR imaging, the investigation of adjacent-level disc disease, and as a means to rule out cases of nonorganic pain from surgical consideration.

Imaging of disk disease and degenerative spondylosis of the lumbar spine

Low back pain is a common but poorly understood entity. Features of degeneration depend on which component of the motion segment is predominantly affected, and include disk space narrowing, vacuum phenomenon, disk desiccation, vertebral osteophyte formation, disk herniation, and facet arthrosis, but these features do not necessarily have any relationship to symptoms. Since most episodes of back pain resolve on their own, and most disk herniations spontaneously regress, imaging of low back pain, although widely performed, is probably not necessary in most cases.

Sensory innervation of the lateral portion of the lumbar intervertebral disc in rats

BACKGROUND CONTEXT

An annular tear extending to the outer one-third of the annulus is thought to be one of the causes of low back pain. However, some patients have bilateral low back symptoms, even if the annular tear is localized in the lateral disc. Because nociceptive information from the lateral disc is transmitted by the dorsal root ganglion (DRG) neurons innervating the lateral disc, we investigated the distribution of the DRG neurons innervating the lateral portion of the disc.

PURPOSE

To clarify the distribution and pathway of the DRG neurons innervating the lateral portion of the L5-L6 disc in rats.

STUDY DESIGN/SETTING

Using the retrograde tracing method, we studied the innervation pattern of the lateral portion of the L5-L6 intervertebral disc in rats.

METHODS

The retrograde transport of Fluoro-Gold (F-G; Fluorochrome, Denver, CO) was used in 22 rats. Subjects included a nontreated group (n=16) and a sympathectomized group (n=6). Seven days after the application of F-G crystals to the left lateral portion of the L5-L6 disc, bilateral T12-L6 DRGs were observed by fluorescent microscopy.

RESULTS

In the nontreated group, of all the F-G-labeled neurons, 93.1% were present in the left DRGs and 6.9% were in the right DRGs. The number of labeled neurons was largest in the left L2 DRGs. In the sympathectomized group, the numbers of labeled neurons in the T13, L1 and L2 DRGs were significantly lower than the numbers in the nontreated group.

CONCLUSION

Results of this study indicate that DRG neurons innervating the lateral portion of the disc are distributed mainly in the ipsilateral side but also in the contralateral side. The DRG neurons in T13, L1 and L2 innervate the lateral portion of the L5-L6 disc through the paravertebral sympathetic trunks.

Purification and quantification of opioid peptides in bone and joint tissues--a methodological study in the rat

The occurrence of methionine-enkephalin-Arg(6)-Phe(7) (MEAP) and dynorphin B (DYNB) representing two main precursors of opioids was analyzed in specimens from rat cortical bone, periosteum, bone marrow and joint tissue by radioimmunoassay (RIA). MEAP and DYNB were extracted in a solution of 4% EDTA in 2 M acetic acid previously proven suitable for extraction of sensory and autonomic neuropeptides in bone and joints. In crude extracts of cortical bone, the immunoreactive (ir) levels of both opioids were under the detection limit of RIA. As for DYNB this also applied to crude extracts of joints and periosteum. Therefore, two purification methods were tested and compared, i.e. reverse phase C 18 and ion exchange chromatography. RIA of the elution fraction disclosed a significant difference between the two methods in terms of recovery, i.e. <5% and 50%, respectively. Thus, purification by ion exchange chromatography prior to RIA appeared to be the most suitable by providing measurable levels of both MEAP and DYNB in all tissues analyzed (highest in bone marrow, lowest in cortical bone). The described method offers a means of quantifying opioid peptides in bone and joints, which may be utilized in the analysis of regulatory mechanisms of nociception, growth and immune responses in different conditions.

Evaluation and treatment of low back pain: an evidence-based approach to clinical care

Low back pain is a common reason for patient visits to a health care provider. For most patients, low back symptoms are nonspecific, meaning that the pain is localized to the back or buttocks and is due to a presumed musculoligamentous process. For patients with radicular leg symptoms, a precise etiology is more commonly identified. The history and physical examination usually provide clues to the uncommon but potentially serious causes of low back pain, as well as to those patients at risk for prolonged recovery. Diagnostic testing should not be a routine part of the initial evaluation, but used selectively based upon the history, examination, and initial treatment response. For patients without significant neurological impairment, initial treatments should include activity modification, nonnarcotic analgesics, and education. For patients whose symptoms are not improving over 2 to 4 weeks, referral for physical treatments is appropriate. A variety of therapeutic options of limited or unproven benefit are available for patients with radicular leg symptoms or chronic low back pain. Patients with radicular pain and little or no neurological findings should receive conservative treatment, but elective surgery is appropriate for those with nerve root compression who are unresponsive to conservative therapy.

Does needle insertion site affect diskography results? A retrospective analysis

STUDY DESIGN

A retrospective clinical data analysis was performed.

OBJECTIVES

To determine the effect of needle insertion site on provocative diskography results, and to ascertain whether performing diskography ipsilaterally to a patient's reported pain leads to a higher rate of false-positives.

SUMMARY OF BACKGROUND DATA

In certain groups of patients, provocative diskography is associated with a significant false-positive rate, which can lead to misdiagnosis and inappropriate treatment. Although purported by some to be a cause of false-positive diskogram results, the effect of needle insertion site on diskography results has yet to be determined.

METHODS

The charts of 127 patients who underwent diskography were evaluated to determine the relationship between the location of pain, needle insertion site, and diskography results.

RESULTS

Performing diskography on the side ipsilateral to a patient's pain did not result in a higher incidence of positive diskogram results.

CONCLUSION

False-positive diskography results are unlikely to result from performing the procedure on the same side as a patient's reported pain.

Guidelines for the use of discography for the diagnosis of painful degenerative lumbar disc disease

OBJECT

Discography has been used as a diagnostic test in the evaluation of patients with recalcitrant low-back pain. Recently, its usefulness has been questioned because of the occurrence of false-positive results as well as the influence of psychological factors on test results. The purpose of this review is to establish the literature support for and against the use of discography. A search of the English-language literature published between 1966 and 2001 was performed. Papers were selected based on inclusion criteria described in the text, and the quality of information was graded using previously described methods.

CONCLUSIONS

The authors propose a set of practice parameters based on the literature. Although the data were not judged adequate for the determination of a treatment standard, parameters for the use of discography are provided at a guideline and option level.

Vertebral osteonecrosis associated with the use of intradiscal electrothermal therapy: a case report

STUDY DESIGN

This report describes a case of vertebral body osteonecrosis associated with the use of intradiscal electrothermal therapy.

OBJECTIVES

To alert clinicians to a previously unreported complication, vertebral body osteonecrosis, after an intradiscal electrothermal therapy procedure.

SUMMARY OF BACKGROUND DATA

The intradiscal electrothermal therapy procedure is a new treatment that has been advocated in the management of chronic low back pain of discogenic origin. The intradiscal electrothermal therapy procedure uses a fluoroscopically guided thermal catheter to heat the intervertebral disc. A review of the literature regarding this procedure has not revealed osteonecrosis as a complication.

METHODS

The patient's work-up and postoperative course are documented, and all medical records were reviewed retrospectively.

RESULTS

The patient's pain had improved only minimally at initial follow-up after L5-S1 combined anterior and posterior spinal fusion, undertaken after intradiscal electrothermal therapy failure.

CONCLUSIONS

Intradiscal electrothermal therapy has gained increasing popularity in the treatment of discogenic low back pain, in large part because of its minimally invasive nature and perceived low risk for major complications. Previous reports in the literature have not noted any major complications associated with the proper use of this device. Clinicians should be advised that intradiscal electrothermal therapy can be associated with complications, which in the current case, led to osteonecrosis of the vertebral body.