Presence Of High-intensity Zone Research Articles

Vertebral Endplate Defects Induced Mechanical Alterations and Disc Calcification.

Cross sectional comparative study. The current study aims to explore the calcification potential (BMP2 expression) of intervertebral discs and its association with the presence of vertebral endplate defects visible on MRI. Forty-seven herniated lumbar disc samples obtained from patients aged 20-76 (31M/16F) undergoing surgery. Five-µm thin sections were stained with H&E in order to assign a histological degeneration score (HDS) from 0-15 on the basis of cell density (0-5), structural alterations (0-4), granular changes (0-3) and mucus degeneration (0-3). Sections were immuno-stained with anti BMP-2 antibodies to observe the calcification potential in these discs. In addition, pre-operativeT2-T1 W MRI images of the lumbar spine were analyzed for the presence and type (typical or atypical) of vertebral endplate defects, grade of disc degeneration (Pfirrmann grade I-V), presence of high intensity zones (HIZ), and Modic changes at the operated level. Vertebral endplate defects, Modic changes & HIZ were observed in 81%, 29% and 21% of patients respectively. Mean HDS & BMP-2 expression was 9 ± 2 and mean 71 ± 36spots/mm2 respectively. Discs with adjacent vertebral endplate defects showed increased cell density (P = .004), mucus degeneration (P = .002), HDS (P = .01) and BMP-2 expression (P = .01). Discs with HIZ also had increased HDS, but significance was seen with increased BMP2 expression (P = .006). HDS showed a positive correlation with BMP 2 expression (r = .30, P = .04). These findings suggest that the altered mechanical environment of discs is strongly associated with BMP-2 expression which is an important marker of intervertebral disc calcification.

Impact of High-intensity Zones on Their Corresponding Lumbar Spine Segments: A Propensity Score-matched Analysis.

Retrospective radiographic study. The aim of this study was to compare disks with and without high-intensity zones (HIZ) to understand the impact of an HIZ on the stability of corresponding lumbar spinal segments. Previous studies have established a relationship between back pain and the presence of HIZ on T2-weighted images of magnetic resonance imaging. These previous studies, however, used either plain radiographs or static (neutral position) magnetic resonance imaging to assess their chosen variables. We retrospectively reviewed 140 consecutive patients with MR images taken in weight-bearing neutral, flexion, and extension positions. We separated segments into those with HIZ and without HIZ and assessed the grade of disk degeneration for each segment. Subsequently, a matched control group was selected from the segments without HIZ. Multiple factors were compared in a univariate analysis. A multinomial logistic regression analysis was conducted to assess the association between angular range of motion (ROM) >10 degrees and translational motion >2 mm with multiple independent variables. Upon assessment of the 700 lumbar segments, 70 (10%) segments had an HIZ and 68 patients had a single HIZ. On univariate analysis, the presence of an HIZ was not found to be significantly associated with degree of fatty muscle degeneration (P=0.969), muscle volume (P=0.646), degree of facet joint osteoarthritis (P=0.706), intervertebral disk height (P=0.077), Modic change (P=0.951), lower endplate shape (P=0.702), upper endplate shape (P=0.655), or degree of disk degeneration (P=0.607). Multifactorial analysis showed that none of the independent variables significantly correlated with angular ROM >10 degrees. For translational motion, the only significant correlation was the Goutallier classification (P=0.017). The presence of HIZ did not significantly affect spinal stability as measured by angular ROM and translational motion and was not associated with significant changes in several quantitative measurements of spine pathology.

Factors associated with lumbar disc high-intensity zone (HIZ) on T2-weighted magnetic resonance image: a retrospective study of 3185 discs in 637 patients

BackgroundIt is well known that internal disc disruption (IDD) is accelerated by factors such as aging and injury. High- intensity zone (HIZ) on lumbar MRI is usually considered a marker of painful IDD. However, many painful IDD show no HIZ. This suggests that the risk factors of HIZ may be different to these of IDD. The purpose was to clarify the correlation between the HIZ on lumbar MR and the factors, including gender, age, body weight, and low back pain (LBP).MethodsCharacteristics were obtained from the medical record. The MR images, biplanar post-discography radiographs, and post-discography CT images were reviewed and rated by two experienced radiologists in a blinded fashion.ResultsAnnular HIZ correlated significantly with age (OR = 1.011), body weight (OR = 1.022), and LBP symptom (OR = 1.527). The lowest two HIZ prevalence rates were in the second and the third decades (11.54% and 7.84%). The highest prevalence was in the sixth decade (38.03%). The body weight was positively associated with the HIZ prevalence. There was a significant difference in HIZ prevalence between symptomatic and asymptomatic patients (36.16% vs. 26.96%, P < 0.05). All the HIZ discs exhibited grade 3 or grade 4 disruptions, but only 9 discs (9/16, 8 exhibited grade 4 annular tears) were detected with exact pain reproduction.ConclusionsIt is demonstrated that the presence of HIZ on lumbar MR image was associated with aging, high body weight, and low back pain symptom. HIZ sign indicated a part of the natural history of disc degeneration but was not an actual source of low back pain.

The association of high-intensity zones on MRI and low back pain: a systematic review

BackgroundMagnetic resonance imaging (MRI) of the lumbar spine is commonly used to identify the source of low back pain (LBP); however, its use has been questionable. Throughout the years, numerous lumbar phenotypes (e.g., endplate abnormalities, Modic changes, black disc) have been studied as possible pain generators. High-intensity zones (HIZs) are of particular interest as they may represent annular tears. However, for over three decades, there has been heated debate as to whether these imaging biomarkers are synonymous with LBP. Therefore, the following study addressed a systematic review of the reported literature addressing the relationship of HIZs and LBP.MethodsA systematic review was conducted via MEDLINE, SCOPUS, Cochrane, PubMed, PubMed Central, EMBASE via Ovid, and Web of Science with the following search terms: “HIZ,” “high intensity zone,” or “high intensity zones” and “low back pain,” “pain,” “lumbago,” and/or “sciatica.” Specific exclusion criteria were also maintained. Two independent reviewers searched the literature, selected the studies, and extracted the data.ResultsWe identified six studies from our search strategy that met the inclusion criteria from a total of 756 possible studies. One cross-sectional population-based study and five comparison studies were identified, which provided information regarding the prevalence of HIZs. The prevalence of HIZs was 3 to 61% in subjects with LBP and 2 to 3% in subjects without LBP. Only three studies suggested a significant association between the presence of HIZ and LBP with or without sciatica.ConclusionsOur systematic review has found evidence that HIZs may be a possible risk factor for LBP; however, a mismatch of the clinical relevance of HIZs between studies still remains. The available evidence is limited by small sample size, heterogeneous study populations, and lack of standardized imaging methods for phenotyping. HIZs may be important lumbar biomarkers that demand further investigation and should be considered in the global imaging assessment of the spine, which may have immense clinical utility. Further large-scale studies with standardized imaging and classification techniques as well as the assessment of patterns of HIZs are necessary to better understand their role with LBP development.

Correlation between high-intensity zone on MRI and discography in patients with low back pain.

The aim of this study was to analyze the correlation between high-intensity zone (HIZ) on magnetic resonance imaging (MRI) of a lumbar disc and positive pain response assessed by discography for the diagnosis and treatment of discogenic low back pain (LBP). Thirty-seven patients aged 21 to 59 years with chronic LBP but without any neurological symptoms or lumbar disc herniation who underwent MRI and subsequent discography were included in this study. During discography, concordant pain was regarded as positive, whereas discordant pain and no pain were regarded as negative. X-ray and computed tomography (CT) after discography with positive pain response were analyzed to correlate with HIZ on MRI. A total of 98 discs underwent discography in 37 patients; 21 discs presented positive pain response, including 10 with HIZ (47.6%). Seventy-seven discs presented negative pain response, including 29 with HIZ (37.6%). The high grade of annular disruption group shows a high proportion of HIZ on MRI. A positive correlation between HIZ and degree of annular disruption was observed. However, no correlation between HIZ and positive pain response was established on discography. The findings confirm that the presence of HIZ on MRI is only a suggestive and screening iconography indication for the diagnosis of discogenic LBP and cannot replace the gold standard of the discography. MRI should be closely integrated with those of discography, and thus, they play a crucial role in selecting operative segments of multilevel lumbar degenerative disk disease.

Factors for Predicting Favorable Outcome of Percutaneous Epidural Adhesiolysis for Lumbar Disc Herniation.

Background. Lower back pain is a common reason for disability and the most common cause is lumbar disc herniation. Percutaneous epidural adhesiolysis has been applied to relieve pain and increase the functional capacity of patients who present this condition. Objectives. In this study, we retrospectively evaluated the factors which predict the outcome of percutaneous epidural adhesiolysis in patients who were diagnosed with lumbar disc herniation. Methods. Electronic medical records of patients diagnosed with lumbar disc herniation who have received percutaneous epidural adhesiolysis treatment were reviewed. The primary outcome was the factors that were associated with substantial response of ≥4 points or ≥50% of pain relief in the numerical rating scale pain score 12 months after the treatment. Results. Multivariate logistic regression analysis demonstrated that the presence of high-intensity zone (HIZ) at magnetic resonance imaging was a predictor of substantial response to percutaneous epidural adhesiolysis for 12 months (P = 0.007). The presence of a condition involving the vertebral foramen was a predictor for unsuccessful response after 12 months (P = 0.02). Discussion and Conclusion. The presence of HIZ was a predictor of favorable long-term outcome after percutaneous epidural adhesiolysis for the treatment of lower back pain with radicular pain caused by lumbar disc herniation.

Clinical and Surgical Correlation with MRI Findings in Herniated Lumbar Disc: Towards Clinical and Surgical Application of the Current Classification Oriented Understanding of the Morphology of the Herniated Lumbar Disc

Background Data: Herniated lumbar discs requiring surgery are evaluated preoperatively by magnetic resonance imaging. This helps the surgeon to appreciate the size, direction and morphology of the herniated disc material and aids planningthe surgical procedure. The currently available MRI based classifications and terminology do correlate clinical, surgical and prognostic information. Purpose: Our study aims to find clinical and/or surgical correlation between the morphology of different disc herniations based on MRI findings with correlation to the clinical and surgical findings. Study Design: Retrospective analysis of 117 patients who had lumbar microdiscectomy for single level herniated lumbar discs.Patients and Methods: Preoperative MRI was thoroughly examined and the level, laterality, the presence of High Intensity Zone (HIZ) on T2 MRI and Modic changes were recorded. Furthermore, all disc levels were analyzed using theMichigan University Grading System (MSU), the Pfirmann grading for degree of disc degeneration. We subdivided the fragment according to its base diameter on sagittal MRI into: uniform, protruded, extruded and sequestrated. Noted was the fragment direction. The signal intensity of the herniated material in T2 weighted images was reported. We then correlated using statistical analysis each of the MSU Grade, Pfirmann Grade, fragment morphology, fragment signal and fragment migration with the preoperative duration of symptoms, self-reported Visual Analogue Score for leg pain (VAS), neurological deficit, sphincters dysfunction and straight leg raising, blood loss, incision length, bony work, the amount of disc material removed and the shape of the fragment, length of hospital stay, early postoperative sciatica, unintended durotomy, recurrent sciatica, redo surgery within the first year. Results: The mean age was 39.3 years, 70% were males, 47% were L4-5, and 47.9% were L5-S1. Unilateral left herniation was reported in 52.1%, right in 31.6%, central in 12%, and bilateral in 4.3%. Patients were classified as IIAB in 36, IIB in 28, III AB in 24, HIZ in 7. Caudal migration was reported in 28.2%, straight posterior in 64.1%, and cranial migration in 7.7%. The fragments were dark gray on T2WI in 66 (56.4%) patients. Fragment base was uniform in 53 (45.3%) patients. Most of our surgically treated disc prolapses were Pfirmann, Grade 3 and 4. There was no statistical significance between any of the preoperative clinical or the surgical or the postoperative parameters and Pfrimann grade, MSU grade, fragment base, fragment signal, sagittal extent(P>0.05). Except for a statistically significance between the disc size according to MSU classification and the severity of the preoperative leg pain (VAS) (P=0.01) and the preoperative SLR (P=0.005). There was also a statistically significant correlation between the operative time and the fragment base (P=0.006) Conclusion: Not all disc herniations are similar. On our first attempt to clinically and surgically correlate some of these classifications, we found few clinical and surgical correlations with herniated fragment morphology. A more surgically oriented classification scheme would be useful and applicable for surgeons to anticipate the degree of difficulty of surgery and the plan required for adequate nerve root decompression. (2015ESJ079)

Can discoblock replace discography for identifying painful degenerated discs?

ObjectivesThe aim of the present study was to intra-individually compare provocative discography and discoblock (disc analgesia) of idiopathic degenerated discs (IDD) results to each other, to clinical parameters, and to MRI findings. By this the value of both diagnostic features should be critically reevaluated. Methods31 intervertebral IDD (Pfirrmann III°–IV°) of 26 patients were analyzed for surgery decision making by combined discoblock/discography procedure in an open MRI at 1T. A correlation analysis was performed between the Dallas Discogram Scale, pain discrimination score (PDS: concordant/discordant/no pain), positive discoblock (Numerical Rating Scale [NRS] reduction by ≥3, 60min after intervention), presence of Modic changes or high intensity zones (HIZ), patient sex and age, intervention level, injection pressure and discography endpoint analysis (pain/pressure/anatomic/volume). ResultsConcordant pain could be evoked in 35% of the IDDs whereas discoblock was positive in 64%. Patients’ age, sex, Dallas I, Dallas II, and Pfirrmann scores, as well as the presence of HIZ did not correlate to PDS or discoblock results. Discoblock correlated positively to concordant pain. Further positive correlation was found between PDS and intervention level/pressure, between discoblock and Modic changes/discography endpoint as well as between HIZ and discography endpoint. ConclusionsWe suggest discoblock to be an additional tool for surgery decision making in patients with IDD because it correlates to concordant pain evoked by provocative discography as well as to presence of Modic changes. Additionally, assessment of a release instead of provocation of pain can be of advantage.

HIZ’s relation to axial load and low back pain: investigated with axial loaded MRI and pressure controlled discography

The aims were to investigate if the detection of high-intensity zones (HIZ) is affected by axial load, and to study the correlation between HIZ and discogenic pain provoked with pressure controlled discography (PCD). 41 consecutive patients with chronic low back pain, referred for discography, were included. Each patient underwent PCD, CT, MRI, and axial loaded MRI (alMRI) within 24 h. 35 patients completed all MRI sequences (140 discs). The detection of HIZ was compared between conventional MRI and alMRI. PCD was performed in 119 of the discs examined at MRI. Provoked pain at PCD was classified into four categories (none/unfamiliar/similar/exact), with the patients' daily pain as reference, and correlated with presence of HIZ. AlMRI did not affect the detection of HIZ compared with conventional MRI. No significant correlation between HIZ and the 4-graded pain response at discography was found (p = 0.34), neither when combining similarly/exactly reproduced pain (p = 0.08). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of HIZ in detecting discs with exactly reproduced pain were 49, 69, 39 and 76 %. When combining similarly/exactly reproduced pain, PPV was higher but still only 70 %. The detection of HIZ was not influenced by axial load. With strict PCD, discogenic pain can neither be confirmed when having HIZ (PPV 39 %) nor ruled out in discs without HIZ (NPV 76 %). Larger PCD studies including quantification of HIZ at conventional and alMRI are needed, before any dynamic component affected by axial load can be ruled out completely.

Inter- and Intraobserver Reliability in Radiographic Assessment of Degenerative Disk Disease

Clinicians use descriptive classification systems when treating patients with low back pain as an adjunct to surgical decision making. Magnetic resonance imaging (MRI) changes, including Modic changes, the presence of a high-intensity zone, and internal disk desiccation, are commonly used descriptors. The question remains whether different clinicians interpret these terms similarly. This study evaluated the inter- and intraobserver reliability of commonly used MRI classifications in patients presenting with low back pain.Sixty-six patients who underwent lumbar spine fusion surgery at a single multiphysician spine specialty practice for degenerative disk disease were identified. For each surgical level, the following MRI variables were determined independently by 3 fellowship-trained spine surgeons: presence or absence of high-intensity zone and/or internal disk desiccation, presence and classification of disk herniation, Modic grade, and disk height. Each surgeon reviewed the same set of MRI studies a second time at least 2 weeks from the first reading. Inter- and intraobserver reliability was determined using multiobserver Kappa coefficients. Intraobserver reliability ranged from 0.563 to 0.988, with greatest agreement in determining disk height. The greatest interobserver agreement was for determining Modic changes (0.819).Controversy remains on the criteria for diagnosing degenerative disk disease. In patients presenting with low back pain diagnosed with degenerative disk disease, the inter- and intraobserver reliability with use of several common MRI diagnostic tools was substantial. These data imply that clinicians interpret these findings in a reproducible fashion and interpret these terms similarly.

Correlation Between MR Imaging and Discography With Provocative Concordant Pain in Patients With Low Back Pain

this study aimed to correlate magnetic resonance (MR) findings and discography with pain response at provocative discography in patients with low back pain. ninety-three patients who underwent MR imaging of the lumbar spine and subsequent provocation discography as part of a clinical evaluation of low back pain were enrolled in the study. MR images were then evaluated for disc degeneration, high-intensity zone (HIZ), and endplate abnormalities. In the procedure of discography, concordant pain was denoted as positive, whereas discordant pain and no pain were denoted as negative. Finally, MR and discographic findings were analyzed by w2 test based on results of concordant pain. discography was conducted on 256 discs successfully, 116 discs of which presented with concordant pain, and the others presented with discordant pain. There were 141 discs we reevaluated as Grade I-III on MR images, 17 of which presented with concordant pain; 115 were evaluated as Grade IV-V, 99 of which presented with concordant pain. HIZ was found in 60 discs,52 of which had concordant pain. The endplate abnormalities we reobserved in 58 discs, 51 of which manifested concordant pain. Concordant pain was significant correlated with Type IV-V discs on discography (w2=144.08, r=0.60, P<0.01), Grade IV-V disc degeneration on MR image (w2=137.11, r=0.59, P<0.01), the presence of HIZ (w2=51.93, r=0.41, P<0.01), and endplate abnormalities (w2=52.76, r=0.41, P<0.01). disc degeneration grades on MR imaging showedan association with discographic grades. Type IV-V discs on discography, Grade IV-V disc on MR images, the presence of HIZ,and endplate abnormalities might indicate discogenic pain inpatients with chronic low back pain.

Prospective Controlled Study of the Development of Lower Back Pain in Previously Asymptomatic Subjects Undergoing Experimental Discography

A prospective controlled longitudinal study. To determine whether subjects, asymptomatic for lower back problems, who undergo experimental discography, will develop lower back problems during the medium term to the full term. Previous work has shown significant pain on discographic injection in approximately 40% of asymptomatic subjects. It has been suggested that those subjects with painful injections would soon develop lower back pain (LBP) syndromes in the near future: that is, the experimental discography was detecting an imminent "pain generator" before clinically symptomatic. METHODS.: Fifty subjects without low back pain were recruited for clinical and psychometric testing, MRI scanning, and experimental lumbar discography to determine the rate of painful lumbar disc injections in select subjects without LBP history. After determining which subjects had painful injections, all subjects completing the discography protocol were prospectively followed at yearly intervals to determine the occurrence of LBP and LBP disability over time. Statistical methods were then used to determine the correlation, if any, between the asymptomatic subjects' clinical, MRI, and discography findings, and the subsequent LBP measures. Controls, not participating in the lumbar discography study, were also followed. Controls were matched for clinical features, sex, age, and occupational/recreational exposure. Follow-up examinations were performed at yearly intervals by blinded researchers using a scripted interview and completing standard questionnaires. A total of 46 of 50 completed the discogram, and all 46 subjects completed the final 4-year follow-up examination. There was a low incidence of LBP episodes in the experimental groups and control. A painful disc injection, independent of psychological profile, did not predict LBP or any other functional outcome measure at follow-up on multivariate analysis. The presence of an anular fissure seen on discography was weakly associated with the cumulative incidence of LBP episodes after discography (P = 0.08). The presence of high intensity zone on MRI in any disc was also weakly associated with the development of LBP episodes (P = 0.09). Psychometric profiles at the start of the study strongly and independently predicted future back pain (P = 0.01), medication usage (P = 0.002), and work loss (P = 0.01) over the 4-year study. Compared with controls not having undergone discography, there was no significant difference in back pain, function, work loss, doctors visits for back pain, or medication intake in any group. A subset in the injection group with somatization disorder had a higher LBP visual analog score compared with somatization disorder controls at 1 year,but this was not significant at 4 years after testing. Painful disc injections are poor independent predictors of subsequent LBP episodes in subjects initially without active lower back complaints. Anular disruption is a weak predictor of future LBP problems. Psychological distress and preexisting chronic pain processes are stronger predictors of LBP outcomes.

Clinical and Radiologic Factors Predicting the Low Back Pain after Discectomy

Study design : Retrospective analysis to evaluate predictive factors of low back pain after discectomy in lumbar disc herniation. Objective : We analysed clinical and radiological predictive factors which possibly contribute to postoperative low back pain in herniated lumbar disc disease. Summary of literature review : There was no statistically significant factors which contribute to postoperative low back pain. Materials and Methods : Ninety two patients with herniated lumbar disc who were treated by one level simple discectomy from June 1995 to June 2000 were included in this study. They were divided into two groups by severity of postoperative low back pain, back pain group and no back pain group. We analyzed clinical and radiological factors retrospectively in each group by medical records, preoperative radiographs and telephone interview. Then statistical analysis was performed with Chi-square test and logistic regression analysis. Confidence interval was 95%. R e s u l t s : Eighteen patients (19.6%) were in back pain group and seventy four patients (80.4%) were in no back pain group. Among patients over 50 years old and below 50 years old, the ratio of low back pain after discectomy was 33% and 13.8% respectively (Odds ratio=3.1, confidence interval 1.07~9.03). It was proved statistically that except age factor, such factors as follows did not affect postoperative lower back pain. Sex, smoking , preceeding low back pain before discectomy, level of discectomy, disc space narrowing, bony spur, grade of disc degeneration, presence of high intensity zone of disc. Conclusions : There was no other significant predictive factors of post-discectomy low back pain than the age over 50 years old.

2000 Volvo Award winner in clinical studies: Lumbar high-intensity zone and discography in subjects without low back problems.

A prospective observational study of patients with low back pain and those without was performed. To investigate the prevalence and significance of a high-intensity zone in a group of patients asymptomatic for low back pain, but who had known risk factors for lumbar disc degeneration. This asymptomatic group was compared with a symptomatic group of patients with respect to the presence of anular high-intensity zone and the pain response with discography. Some authors have estimated the prevalence of a high-intensity zone in a group of symptomatic patients to be 86%. They have reported a strong correlation between a high-intensity zone and positive discography in patients with low back pain. Other investigators have reported evidence either supporting or discounting these findings. Patients with low back pain and those without underwent physical examination, psychometric testing, plain radiograph, magnetic resonance imaging, and discography. The presence of a high-intensity zone, anular disruption, and positive discographic pain then were compared between the two groups. There were strict inclusion criteria for both groups. A total of 109 discs in 42 patients were evaluated in the symptomatic group and compared with 143 discs in 54 patients in the asymptomatic group. The presence of a high-intensity zone was determined by a standardized criteria on T2-weighted magnetic resonance images. Psychometric testing also was administered to each patient before discography. Standard discography was performed on all the patients, and the pain response was recorded using a visual analog scale according to the Walsh et al criteria. The prevalence of a high-intensity zone in the patient populations was 59% in the symptomatic group and 24% in the asymptomatic group. In the symptomatic group, 33 (30.2%) of 109 discs were found to have a high-intensity zone. In the asymptomatic group, 13 of 143 discs were found to have a high-intensity zone. In the symptomatic group, 72.7% of the discs with a high-intensity zone were positive on discography, whereas 38.2% of the discs without a high-intensity zone were positive. In the asymptomatic group, 69.2% of the discs with a high-intensity zone were positive on discography, whereas 10% of the discs without a high-intensity zone were positive. In the patients with normal psychometric testing, 50% of the discs with a high-intensity zone were positive on discography, as compared with 100% positive discography results in patients with abnormal psychometric testing or chronic pain. The presence of a high-intensity zone does not reliably indicate the presence of symptomatic internal disc disruption. Although higher in symptomatic patients, the prevalence of a high-intensity zone in asymptomatic individuals with degenerative disc disease (25%) is too high for meaningful clinical use. When injected during discography, the same percentage of asymptomatic and symptomatic discs with a high-intensity zone were shown to be painful.

The clinical significance of the high-intensity zone on lumbar spine magnetic resonance imaging.

Prospective observational study of anular tears, diagnosed by a high-intensity zone within the anulus on lumbar spine magnetic resonance imaging, and correlation with the clinical features. To assess the prevalence of high-intensity zones in patients who are investigated for back and leg pain and to determine whether there are clinical features that can be used for diagnosis of the presence of a high-intensity zone. Results in previous studies have shown that the presence of a high-intensity zone is associated with reproduction of a patient's pain on stress discography. Neural compression on magnetic resonance imaging has been shown to be associated with back pain, but to date, no study has correlated the presence of a high-intensity zone with the clinical features. The lumbar spine magnetic resonance images in 156 patients in whom back and leg pain were investigated were analyzed for the presence and appearances of high-intensity zones. The clinical features of those patients with a high-intensity zone but with no evidence of neural compression on magnetic resonance imaging were analyzed by t test and X2 test. A high-intensity zone occurred in patients at a prevalence of 45.5% and usually occurred posteriorly (77%) and posterolaterally (22%) within the anulus. There were no features within the history, functional disability questionnaire, or physical examination that aided in a clinical diagnosis of those patients with a high-intensity zone. A high-intensity zone is a common finding in patients in whom low back and leg pain are investigated, but the presence of a high-intensity zone does not define a group of patients with particular clinical features.