Three-dimensional evaluation of lumbar disc hernia and prediction of absorption by enhanced MRI

Differentiating Lumbar Spinal Etiology from Peripheral Plexopathies

Clinicians have managed and treated lower back pain since the earliest days of practice. Historically, lower back pain and its accompanying symptoms of radiating leg pain and muscle weakness have been recognized to be due to any of the various lumbar spine pathologies that lead to the compression of the lumbar nerves at the root, the most common of which is the radiculopathy known as sciatica. More recently, however, with the increased rise in chronic diseases, the importance of differentially diagnosing a similarly presenting pathology, known as lumbosacral plexopathy, cannot be understated. Given the similar clinical presentation of lumbar spine pathologies and lumbosacral plexopathies, it can be difficult to differentiate these two diagnoses in the clinical setting. Resultingly, the inappropriate diagnosis of either pathology can result in ineffective clinical management. Thus, this review aims to aid in the clinical differentiation between lumbar spine pathology and lumbosacral plexopathy. Specifically, this paper delves into spine and plexus anatomy, delineates the clinical assessment of both pathologies, and highlights powerful diagnostic tools in the hopes of bolstering appropriate diagnosis and treatment. Lastly, this review will describe emerging treatment options for both pathologies in the preclinical and clinical realms, with a special emphasis on regenerative nerve therapies.

Non-surgical treatment of giant tumor-like lumbar disc herniation based on enhanced MRI: A case series

RATIONALE

In recent clinical follow-up, it has been vertified that resorption in lumbar disc herniation (LDH) could be of great curative effect in non-surgical treatment for LDH. However, reports of resorption in giant tumor-like LDH are rarely mentioned due to its risk of irreversible neurological damage which could be caused by long-term non-surgical treatment. In our clinical observations, we have found that enhanced MRI helps to distinguish LDH from intradural tumours and to predict the probability of resorption in LDH. We analyzed 8 patients with giant tumor-like LDH who underwent non-surgical treatment, and these patients had resorption during follow-up. All patients were examined with enhanced MRI before treatment, and the type of "bull's eye" sign classification was determined by images. The MRI protrusion volume(VP), resorption rate(HR%) and JOA score of patients at the first visit and the last follow-up were recorded.

PATIENT CONCERNS

8 patients of Han ethnicity were admitted to the department of orthopedic complaining of low back pain for 1week to 12months. They were diagnosed with giant tumor-like LDH by enhanced MRI.

DIAGNOSES

These patients were diagnosed with giant tumor-like LDH.

INTERVENTIONS

We adopted a non-surgical treatment plan for the patients, including taking oral non-steroidal anti-inflammatory agents and performing rehabilitation exercise. In consideration of the risk of irreversible neurological damage, patients were closely observed during treatment and follow-up. Once the following conditions occur, surgical treatment is required immediately: The symptoms are not signifcantly relieved after 3 to 6 months of non-surgical treatment; The symptoms are aggravated by non-surgica treatment; The clinical manifestations of cauda equina syndrome.

OUTCOMES

After treated with oral non-steroidal anti-inflammatory agents and rehabilitation exercise, the resorption was accompanied by clinical symptom relief. No neurological damage occurred in all patients, and the clinical symptoms did not recur in the subsequent follow-up.

LESSONS

Clinicians should fully consider the possibility of resorption prior to surgical treatment in patients with giant LDH. We can predict the probability of resorption in patients with giant LDH based on enhanced MRI. For patients with a high probability of resorption, we can choose non-surgical treatment in the absence of progressive neurological impairment and cauda equina syndrome.

Characteristics and mechanisms of resorption in lumbar disc herniation

Lumbar disc herniation (LDH) can be spontaneously absorbed without surgical treatment. However, the pathogenesis and physiological indications for predicting protrusion reabsorption are still unclear, which prevents clinicians from preferentially choosing conservative treatment options for LDH patients with reabsorption effects. The purpose of this review was to summarize previous reports on LDH reabsorption and to discuss the clinical and imaging features that favor natural absorption. We highlighted the biological mechanisms involved in the phenomenon of LDH reabsorption, including macrophage infiltration, inflammatory responses, matrix remodeling, and neovascularization. In addition, we summarized and discussed potential clinical treatments for promoting reabsorption. Current evidence suggests that macrophage regulation of inflammatory mediators, matrix metalloproteinases, and specific cytokines in intervertebral disc is essential for the spontaneous reabsorption of LDH.

THE MICROSCOPIC AND ENDOSCOPIC TECHNIQUES IN LUMBAR DISCECTOMY: A SYSTEMATIC REVIEW

ABSTRACT Objectives: To compare microdiscectomy (MD) and endoscopic interlaminar discectomy (EID) as methods for the surgical treatment of lumbar disc herniation, describing their efficiency in reducing hospitalization time, pain, and neurological deficit, and comparing the findings and the quality of studies that used the microscopic and endoscopic techniques. Methods: A systematic literature review that used the PRISMA protocol as a methodology. The search was conducted in the PUBMED/MEDLINE and The Cochrane Library databases, using publications from the last 5 years in Portuguese and English. After applying the inclusion and exclusion criteria and validating the qualified studies via STROBE and CONSORT, there were a total of 16 studies for data compilation. Results: A sample of 1004 patients who underwent lumbar discectomy was obtained, 62% of whom were male, and 493 of whom underwent EID (49%) and 511 MD (51%). The mean patient age was 38.7 years and the predominant vertebral level operated was L5-S1 (64.8%). The EID had shorter surgical time (66.38 min) and hospitalization time (3.3 days), in addition to greater variation in the VAS LLLL score (5.38), while the MD presented greater variation in the VAS LUMBAR score (3.14). Conclusion: EID demonstrated efficacy like that of MD, given the similarity in the results obtained, in addition to non-inferiority in the reduction of pain and neurological deficit, and superiority in surgical and hospitalization times. Level of Evidence I; Systematic review .

Predictors of the conservative management outcomes in patients with lumbar herniated nucleus pulposus: A prospective study in Indonesia

BACKGROUND

The objective of this study was to identify the predictors of the conservative management outcomes in patients with lumbar herniated nucleus pulposus (HNP).

METHODS

A prospective study was conducted between June 2010 and April 2012 in Banda Aceh, Indonesia. Clinical and baseline neurologic examinations such as passive straight leg raising test (SLRT), cross SLRT, and patellar and Achilles reflexes were assessed prior to the conservative management. The patients were evaluated at 2nd, 4th, 8th, 12th and 24th week following commencement of the conservative management.

RESULTS

We recruited and followed 171 HNP patients of which 35.7% of them had good outcome. At univariate analysis, patients with more than 12 months duration of complaint, those with dominant radicular pain, severe pain intensity (visual analogue scale 7-10), positive SLRT, positive cross SLRT, and reduced motor power of knee extensors (muscle strength grade 1-4), were associated with poor outcome. Multivariate analysis suggested that patients with dominant radicular type of pain were likely to had poor outcome compared to those with dominant back pain (odd ratio (OR) 10.57 with 95% confidence interval (CI) 1.15-96.93). Patients with reduced motor power of knee extensors also had a higher chance to have poor outcome compared to those who were normal (OR: 10.57; 95% CI: 1.15-96.93).

CONCLUSION

Type of pain and the strength of lower extremities could be able to predict the failure of conservative management in patients with lumbar disc herniation. However, further studies with the bigger sample size are warrant to validate our results.

The incidence of regression after the non-surgical treatment of symptomatic lumbar disc herniation: a systematic review and meta-analysis

BACKGROUND

Although the regression of symptomatic lumbar disc herniation (SLDH) has been widely reported, little data exist regarding the generalized incidence of regression (IR). We aimed to review the varying IRs and to synthesize the pooled IR of non-surgically-treated SLDH.

METHODS

Four electronic databases were searched for relevant studies pertaining to the regression of SLDH after non-surgical treatment and for potential studies that may have reported morphological changes in lumbar disc herniation in the follow-up results of SLDH patients treated non-surgically. The main outcome was the regression of SLDH. A random effects model was used to determine the pooled IR of SLDH.

RESULTS

We identified 13,672 articles, 38 of which were eligible for analysis. Our analysis included 2219 non-surgically treated SLDH patients, 1425 of whom presented regression. The pooled IR was 63% (95% CI 0.49-0.77). In subgroup analyses, studies that quantitatively measured the regression of SLDH yielded statistically higher pooled IRs than those that used qualitative methods. The pooled IRs gradually increased in randomized controlled trials and prospective and retrospective studies. The pooled IR varied from 62 to 66% after the sequential omission of any single study. Meta-regression showed that study types, herniation levels and regression measurements caused heterogeneity.

CONCLUSIONS

We report an overall IR of 63% among non-surgically treated SLDH patients, thus providing clinical decision makers with quantitative evidence of IR. Based on our systematic review, we suggest a follow-up timeline with time points 4 and 10.5 months after onset when deciding whether to perform surgery for SLDH.

Predicting conservative treatment failure in patients with lumbar disc herniation. Single center, case-control study

OBJECTIVES

The aim of this study was to identify independent predictors of conservative treatment failure in patients presenting due to lumbar disc herniation-associated low back pain and sciatica.

PATIENTS AND METHODS

This is a single institution, case-control study including 240 patients that were selected for microsurgical or conservative treatment due to lumbar disc herniation in a 2,5-year period. Bivariate and multivariate analyses were performed in order to identify independent predictors among demographic, clinical and radiographic factors.

RESULTS

Statistically significant differences were observed between conservatively and surgically managed groups in bivariate analysis. Logistic regression models further revealed that leg paresthesia (p =  0,003; OR = 5,136) and percentage of spinal canal stenosis ratio (p < 0,001; OR = 1,055) had the strongest, independent correlation with conservative treatment failure in our cohort. Back-to-leg ratio did not reach statistical significance although it proved a strong correlation in bivariate analysis (p < 0,001, Cramér's V = 0,53).

CONCLUSION

Increasing % canal compromise ratio (cut-off value 23%) and co-occurrence of leg paresthesia were the most important risk factors for surgery in our series of patients.

The probability of spontaneous regression of lumbar herniated disc: a systematic review

OBJECTIVE

To determine the probability of spontaneous disc regression among each type of lumbar herniated disc, using a systematic review.

DATA SOURCES

Medline, Cochrane Library, CINAHL, and Web of Science were searched using key words for relevant original articles published before March 2014. Articles were limited to those published in English and human studies.

REVIEW METHODS

Articles had to: (1) include patients with lumbar disc herniation treated conservatively; (2) have at least two imaging evaluations of the lumbar spine; and (3) exclude patients with prior lumbar surgery, spinal infections, tumors, spondylolisthesis, or spinal stenosis. Two reviewers independently extracted study details and findings. Thirty-one studies met the inclusion criteria. Furthermore, if the classification of herniation matched the recommended classification of the combined Task Forces, the data were used for combined analysis of the probability of disc regression of each type. Nine studies were applicable for probability calculation.

RESULTS

The rate of spontaneous regression was found to be 96% for disc sequestration, 70% for disc extrusion, 41% for disc protrusion, and 13% for disc bulging. The rate of complete resolution of disc herniation was 43% for sequestrated discs and 15% for extruded discs.

CONCLUSIONS

Spontaneous regression of herniated disc tissue can occur, and can completely resolve after conservative treatment. Patients with disc extrusion and sequestration had a significantly higher possibility of having spontaneous regression than did those with bulging or protruding discs. Disc sequestration had a significantly higher rate of complete regression than did disc extrusion.

A morphometric cadaver study of the anterior lumbar epidural space

INTRODUCTION

Free disc fragments end often up in the concavity of the anterior epidural space. This space consists of two compartments. The discrepancy between the impressive magnetic resonance imaging findings, clinical symptoms in patients and the problem of treatment options led us to the anatomical determination of anterior epidural space volumes.

MATERIALS AND METHODS

For the first time, the left and right anterior epidural volume between the peridural membrane and the posterior concavity of the lumbar vertebral bodies L3-S1 were determined for each segment. A CT scan and a polyester resin injection were used for the in vitro measurements.

RESULTS

The volumes determined in human cadavers using this method ranged from 0.23 ccm for L3 to 0.34 ccm for L5. The CT concavity volume determination showed this increase in volume from cranial to caudal, as well.

CONCLUSION

This volume is large enough to hold average-sized slipped discs without causing neurological deficits. A better understanding of the anterior epidural space may allow a better distinction of patient treatment options.

Degenerative Disease of the Spine

Degenerative disease of the spine is a definition that includes a wide spectrum of degenerative abnormalities. Degeneration involves bony structures and the intervertebral disk, although many aspects of spine degeneration are strictly linked because the main common pathogenic factor is identified in chronic overload. During life the spine undergoes continuous changes as a response to physiologic axial load. These age-related changes are similar to pathologic degenerative changes and are a common asymptomatic finding in adults and elderly persons. A mild degree of degenerative changes is paraphysiologic and should be considered pathologic only if abnormalities determine symptoms. Imaging allows complete evaluation of static and dynamic factors related to degenerative disease of the spine and is useful in diagnosing the different aspects of spine degeneration.

Magnetic Resonance Imaging Findings as Predictors of Clinical Outcome in Patients With Sciatica Receiving Active Conservative Treatment

OBJECTIVE

The aims of this study were to investigate the possible prognostic value of disk-related magnetic resonance imaging (MRI) findings in relation to recovery at 14 months in patients with severe sciatica, and whether improvement of disk herniation and/or nerve root compromise is concurrent with recovery.

METHODS

All patients included in this prospective observational study of patients with sciatica receiving active conservative treatment were scanned at baseline and at 14 months' follow-up. Definite recovery at follow-up was defined as an absence of sciatic leg pain and a Roland Morris disability score of 3 or less. Potential predictors of interest were disk-related MRI findings in the lumbar spine. Bi- and multivariate logistic regression analyses were used to identify any predictors of recovery. Age, sex, and treatment were included in the analyses as possible confounding/modifying factors.

RESULTS

According to the definitions used, 53% of 154 patients recovered; 63% of men (n = 84) and 40% of women (n = 70). In the multivariate analyses, broad-based protrusions, extrusions, and male sex were found to be predictive of a positive outcome. Sex was identified as a true confounder in that the prevalence of disk-related MRI findings was different for men and women, and they had different recovery rates. Improvement of disk herniations and nerve root compromise over time did not coincide with definite recovery.

CONCLUSIONS

In patients with sciatica receiving active conservative treatment, broad-based protrusions and extrusions at baseline were positive predictors of definite recovery at 14 months. However, at 14 months the MRI-defined improvement of disk herniations and nerve root compromise was not correlated with definite recovery.

The effect of lumbar flexion and extension on disc contour abnormality measured quantitatively on magnetic resonance imaging

STUDY DESIGN

Experimental study with subjects as their own control.

OBJECTIVE

To determine if lumbar disc contour abnormality dimensions, measured quantitatively, differ in flexed, neutral or extended positions.

SUMMARY OF BACKGROUND DATA

MRIs obtained lying supine are used to determine the degree of lumbar disc contour abnormality (bulging or herniation). Variations in positioning are suspected to influence this assessment.

METHODS

Lumbar MR images for 26 male volunteers (24-74 years of age), with or without low back pain, were obtained with the subjects lying in neutral, maximal flexion, and maximal extension positions allowable within a conventional 1.5T MR scanner. Quantitative measures of anterior and posterior disc contour abnormality were obtained for each position.

RESULTS

Statistically significant differences in disc angles were obtained between positions (2-5 degrees) for all levels. Posterior contour abnormality was significantly smaller in flexion and extension than in the neutral position (9.5%-30.1%). Posterior contour abnormality in extension was similar or smaller than in flexion. Anterior contour abnormality was significantly smaller in extension than flexion and smaller in the neutral position than flexion.

CONCLUSION

Spine position should be standardized when assessing disc contour abnormality with MRI. The largest measured disc contour abnormalities when lying supine in a standard MR scanner are observed in the neutral position, as opposed to flexion or extension.

Natural course of disc morphology in patients with sciatica: an MRI study using a standardized qualitative classification system

STUDY DESIGN

A prospective observational study of patients with sciatica.

OBJECTIVES

To describe the 14-month development of disc-related MRI findings in patients with sciatica receiving active conservative treatment.

SUMMARY OF BACKGROUND DATA

Previous studies of disc changes over time have reported reduction of herniations in 35% to 100% of cases. This wide range may be explained by differences in patient populations and classifications used to describe disc herniations.

METHODS

Data were obtained from patients with radicular pain (n = 181) who were randomly allocated into one of two active conservative treatment regimens lasting 8 weeks. All patients were scanned at baseline and at 14 months of follow-up. Variables of interest in the present study were disc contour and nerve root compromise at the presumed symptomatic disc level. Disc contour was assessed using the recommendations from the Combined Task Forces of NASS, ASSR, and ASNR.

RESULTS

In all, 154 patients were included in this study (70 women and 84 men; range, 18-65 years; mean and median age, 45 years). It was possible to identify the symptomatic disc level in 90% of patients. Extrusions or sequestrations were more common in individuals younger than 45 years and in men. Men were also more likely to have nerve root compromise. Only 3% of bulges and 38% of focal protrusions improved, whereas 75% to 100% of broad-based protrusions, extrusions, and sequestrations improved (P < 0.0001). Nerve root compromise improved in 21% to 80% depending on the disc contour. Neither type of treatment nor age had any effect on the development of MRI findings over time. However, nerve root compromise was more likely to improve in men.

CONCLUSIONS

This classification system could be used to identify the majority of symptomatic disc levels. At 14 months, the MRI outcome was generally good for disc herniations and nerve root compromise. Nerve root compromise had the best MRI prognosis if the disc was extruded at baseline. There were significant differences between men and women in relation to baseline findings as well as in relation to development of MRI findings over time.

Degenerative disorders of the spine

Patients with back pain and degenerative disorders of the spine have a significant impact on health care costs. Some authors estimate that up to 80% of all adults experience back pain at some point in their lives. Disk herniation represents one of the most frequent causes. Nevertheless, other degenerative diseases have to be considered. In this paper, pathology and imaging of degenerative spine diseases will be discussed, starting from pathophysiology of normal age-related changes of the intervertebral disk and vertebral body.

Spontaneous resolution of lumbar disk herniation: predictive signs for prognostic evaluation

Spontaneous regression of lumbar disk herniation in patients who did not undergo surgery nor interventional therapy is reported in up to 70% of cases; however, no perspective study has clarified the possible predictive signs of a positive evolution. Aim of our study was to search for plan and contrast enhancement MRI signs able to define disk-herniation resolution. We enrolled 64 patients, affected by 72 lumbar disk herniations as per the classification proposed by the American Society of Neuroradiology (Nomenclature and Classification of Lumbar Disk Pathology 2001). MRI examinations were performed by 1.5-T magnet, using T1w SE sequences on sagittal and axial planes, before and after contrast, and T2w FSE ones on the same planes. The following parameters were considered: age, sex, level and size of disk herniation, its relationship to the spinal canal, clinical onset interval, type of disk herniation, herniated-material signal intensity on T2w sequences and its pattern of contrast enhancement. All the patients, conservatively treated, underwent clinical and MRI follow-up examination after 6 months. At MRI follow-up exams spontaneous regression of disk herniation was observed in 34.72% of cases. Among these, free fragments regressed in 100% of cases, herniations with high signal intensity on T2w sequences in 85.18%, herniations with peripheral contrast-enhancement in 83% of cases. Disk-herniation evolution did not show any relationship with location, size and level. Our study demonstrates that MRI, in addition to its high diagnostic value, offers predictive information about disk-herniation evolution.