Herniated intervertebral disc-associated periradicular fibrosis and vascular abnormalities occur without inflammatory cell infiltration

Lumbar Spinal Stenosis and Potential Management With Prostaglandin E1 Analogs

ABSTRACT

Lumbar spinal stenosis is one of the most commonly diagnosed spinal disorders worldwide and remains a major cause for surgery in older adults. Lumbar spinal stenosis is clinically defined as a progressive degenerative disorder with low back pain and associated neurogenic intermittent claudication. Conservative and surgical management of lumbar spinal stenosis has been shown to be minimally effective on its symptoms. A treatment option that has not been investigated in the United States is the utilization of prostaglandin E1 analogs, which have been used primarily in Japan for the treatment of lumbar spinal stenosis since the 1980s. The vasodilatory and antiplatelet aggregation effects of prostaglandin E1 presumably improve symptoms of lumbar spinal stenosis by increasing blood flow to the spinal nerve roots. This brief report examines the potential vascular pathology of lumbar spinal stenosis, reviews evidence on the use of prostaglandin E1 analog limaprost in Japan for lumbar spinal stenosis, and briefly discusses misoprostol as a possible alternative in the United States. The studies summarized in this report suggest that prostaglandin E1 analogs may provide benefit as a conservative treatment option for patients with lumbar spinal stenosis. However, higher-quality studies conducted in the United States and comparison with other currently used conservative treatments are required before it can be recommended for routine clinical use.

Percutaneous cervical coblation as therapeutic technique in the treatment of algo-dysfunctional pain of discal herniation

OBJECTIVE

To confirm the validity of coblation nucleoplasty in reduction of cervical discogenic nature.

STUDY DESIGN

In a monocentric prospective clinical observational study recruiting 20 patients, treated with percutaneous coblation for cervical discogenic pain in 16 months in our hospital, we have clinically evaluated 18 patients. The pain was scored with the Visual Analogic Scale (VAS) in a pre-procedural questionary, 3/4 monthly follow-up from treatment and, finally, in a long-term follow-up 2 years after procedure.

RESULTS

The mean pre-procedural VAS score was 7.9 ± 1.6 (95%-Confidence Interval 7.198-8.634), while the mean post-procedural score after 3-4 months has been 2.5 ± 3.1 (95%-Confidence Interval 1.089-3.965) and 2.5 ± 2.5 (95%-Confidence Interval 1.367-3.687) after 2 years. Among 18 patients, in the shortly post-treatment follow-up, nine had a complete pain relief, four had a > 50% VAS reduction, two hada < 50% VAS reduction, three did not have any variation of VAS; after 2 years, six patients had a total pain resolution, eight had a > 50% VAS reduction, two hada < 50% VAS reduction, two did not have any benefit. No peri- and post-procedural complication has been observed.

CONCLUSIONS

In a spite of a little sample, our results showed coblation as a valid therapeutic option to reduce cervical discogenic pain in medicine-refractory patients, as an alternative or a previous choice before a more invasive surgical treatment.

Aberrant mechanosensing in injured intervertebral discs as a result of boundary-constraint disruption and residual-strain loss

In fibrous tissues, pre-stressed boundary constraints at bone interfaces instil residual strain throughout the tissue, even when unloaded. For example, internal swelling pressures in the central nucleus pulposus of the intervertebral disc generate pre-strain in the outer annulus fibrosus. With injury and depressurization, these residual strains are lost. Here, we show that the loss of residual strains in the intervertebral disc alters the microenvironment and instigates aberrant tissue remodelling and the adoption of atypical cellular phenotypes. By using puncture surgery of the annulus fibrosus in rabbits, ex vivo puncture experiments, and electrospun nanofibrous scaffolds recapitulating evolving boundary constraints, we show that the loss of residual strain promotes short-term apoptosis and the emergence of a fibrotic phenotype, that local fibre organization and cellular contractility mediate this process, and that the aberrant cellular changes could be abrogated by targeting the cell-mechanosensing machinery with small molecules. Our findings indicate that injury to dense connective tissues under pre-strain alters boundary constraints and residual strain, leading to aberrant mechanosensing, which in turn promotes disease progression.

A review of the role of epidural percutaneous neuroplasty

Degeneration, whether from age or postsurgical, in the ventral and lateral epidural space can lead to irritation of both the nerve roots and of the nerves present in the epidural space, the peridural membrane and the posterior longitudinal ligament. This irritation is often accompanied by mild scarring. Neuroplasty is a specific procedure designed to relieve this irritation. The effectiveness of neuroplasty is not affected by the extent of spinal stenosis. Neuroplasty can be performed in the lumbar, thoracic and cervical spine, and using caudal, transforaminal and interlaminar approaches. Postprocedural home exercises are an integral part of the procedure. There are multiple high-grade studies positive for the effectiveness and safety of neuroplasty. Neuroplasty should be offered prior to surgery in patients with persistent back and/or extremity pain.

Radiculopathy Contralateral to the Side of Disc Herniation -Microendoscopic Observation

INTRODUCTION

There are patients with lumbar disc herniation (LDH) having contralateral sciatic symptoms although the mechanisms of this clinical feature are still not well understood. The purpose of this study was to investigate these mechanisms by microendoscopic findings.

METHODS

Patients were performed microendoscopic surgery using over-the-top approach (ME-OTT), with laminoplasty, extirpation of herniation, and observation of the contralateral nerve root. The over-the-top approach was applied through the same incision from the herniation side. Clinical results were assessed according to the clinical scoring system established by the Japanese Orthopedic Association (JOA) score.

RESULTS

This study consisted of five patients, with the average age of 55.6 years old. The mean preoperative JOA score was 13 points. Three cases were Grade II and two were Grade III degrees of disc herniation. Levels of herniation were one at L3-4 and four at L4-5. Remission of sciatic symptoms was obtained in all cases after surgery. The average and percent improvements (%IP) of JOA scores at 2 months after surgery were 27.8 points and 92%, respectively. By the approach from the herniation side using ME-OTT, image around the contralateral nerve root was obtained without radical intervention. By ME-OTT, redness of the nerve root and fibrosis around the symptomatic nerve root were identified, whereas inflammatory changes were not apparent on the ipsilateral nerve root.

CONCLUSIONS

Operative treatment of LDH with contralateral symptoms by ME-OTT was a useful procedure for decompression and observation of the affected nerve root. Asymptomatic disc herniation, "silent disc herniation," was considered at the herniation side since there were less inflammatory changes around the ipsilateral nerve root. In contrast, compression of dura toward the opposite side by disc herniation could have led to mechanical stress against the contralateral nerve root and triggered inflammation at lateral recess, resulting in radicular pain.

Efficacy of Percutaneous Adhesiolysis in the Treatment of Lumbar Post Surgery Syndrome

Context

Lumbar post-surgery syndrome is common and often results in chronic, persistent pain and disability, which can lead to multiple interventions. After failure of conservative treatment, either surgical treatment or a nonsurgical modality of treatment such as epidural injections, percutaneous adhesiolysis is often contemplated in managing lumbar post surgery syndrome. Recent guidelines and systematic reviews have reached different conclusions about the level of evidence for the efficacy of epidural injections and percutaneous adhesiolysis in managing lumbar post surgery syndrome. The objective of this systematic review was to determine the efficacy of all 3 percutaneous adhesiolysis anatomical approaches (caudal, interlaminar, and transforaminal) in treating lumbar post-surgery syndrome.

Evidence Acquisition

Data Sources: A literature search was performed from 1966 through October 2014 utilizing multiple databases. Study Selection: A systematic review of randomized trials published from 1966 through October 2014 of all types of epidural injections and percutaneous adhesiolysis in managing lumbar post-surgery syndrome was performed including methodological quality assessment utilizing Cochrane review criteria, Interventional Pain Management Techniques–Quality Appraisal of Reliability and Risk of Bias Assessment (IPM–QRB), and grading of evidence using 5 levels of evidence ranging from Level I to Level V. Data Extraction: The search strategy emphasized post-surgery syndrome and related pathologies treated with percutaneous adhesiolysis procedures.

Results

The search criteria yielded 16 manuscripts on percutaneous adhesiolysis assessing post-surgery syndrome. Of these, only 4 randomized trials met inclusion criteria for methodological quality assessment, 3 of them were of high quality; and the fourth manuscript was of low quality. Based on these 3 randomized controlled trials, 2 of them with one-day procedure and one with a 3-day procedure, the level of evidence for the efficacy of percutaneous adhesiolysis is Level II based on best evidence synthesis.

Conclusions

Based on this systematic review, percutaneous adhesiolysis is effective in managing patients with lumbar post-surgery syndrome after the failure of conservative management including fluoroscopically directed epidural injections.

Percutaneous Adhesiolysis Versus Transforaminal Epidural Steroid Injection for the Treatment of Chronic Radicular Pain Caused by Lumbar Foraminal Spinal Stenosis: A Retrospective Comparative Study

OBJECTIVE

To investigate the efficacy of percutaneous adhesiolysis (PA) compared to fluoroscopy (FL)-guided transforaminal epidural steroid injection (TFESI) in patients with radicular pain caused by lumbar foraminal spinal stenosis (LFSS) by assessing pain relief and functional improvement at 4 and 12 weeks post-procedure.

METHODS

This retrospective study included 45 patients who underwent PA or FL-guided TFSEI for radicular pain caused by LFSS of at least 3 months' duration. Outcomes were assessed with the Oswestry Disability Index (ODI) and Verbal Numeric Pain Scale (VNS) before the procedure and at 4 and 12 weeks post-procedure. A successful outcome was defined by >50% improvement in the VNS score and >40% improvement in the ODI score.

RESULTS

ODI and VNS scores improved 4 and 12 weeks post-procedure in both groups. Statistically significant differences between groups were observed in ODI and VNS at 12 weeks (p<0.05). The proportion of patients with successful outcomes was significantly different between the two groups only at the 12-week time point.

CONCLUSION

Our study suggests that PA is effective for pain reduction and functional improvement in patients with chronic radicular pain caused by LFSS. Therefore, PA can be considered for patients with previous ineffective responses to conservative treatment. Although PA seems to be more effective than TFEFI according to the results of our study, in order to fully elucidate the difference in effectiveness, a prospective study with a larger sample size is necessary.

Effectiveness and Factors Associated with Epidural Decompression and Adhesiolysis Using a Balloon-Inflatable Catheter in Chronic Lumbar Spinal Stenosis: 1-Year Follow-Up

OBJECTIVES

This study aimed to investigate the efficacy of the combined balloon decompression with a balloon-inflatable catheter (ZiNeu) in addition to conventional epidural adhesiolysis, and to identify factors that predict patient responses.

STUDY DESIGN

An institutional single-armed prospective observational study.

SUBJECTS

Chronic refractory lumbar spinal stenosis.

METHODS

This study was performed in 61 patients with spinal stenosis who suffered from chronic (at least 3 months) lumbar radicular pain with or without lower back pain. Patients had failed to maintain improvement for more than 1 month with conventional epidural injection. The numeric rating scale (NRS) and Oswestry disability index (ODI) were each measured at 1, 3, 6, and 12 months after percutaneous epidural adhesiolysis and balloon decompression with a ZiNeu catheter.

RESULTS

The percentage of successful responders was 72.1%, 60.7%, 57.4%, and 36.1% of patients at 1, 3, 6, and 12 months, respectively. A single combined treatment of percutaneous epidural adhesiolysis and balloon decompression with a ZiNeu catheter provided sufficient pain relief and functional improvement in patients with chronic refractory lumbar spinal stenosis, and the improvement was maintained for 12 months (P < 0.001). Multivariate logistic regression analysis showed that absence of diabetes independently predicted successful response at 12 months after percutaneous epidural decompression and adhesiolysis with the balloon catheter (Odds ratio = 0.080; 95% confidence interval = 0.009-0.676; P = 0.020).

CONCLUSIONS

The combined epidural adhesiolysis and balloon decompression with a ZiNeu catheter led to significant pain relief and functional improvement in a subset of patients with refractory spinal stenosis.

Feasibility of Contralateral Oblique Fluoroscopy-guided Cervical Interlaminar Steroid Injections

BACKGROUND

Cervical epidural steroid injection (CESI), given in conjunction with local anesthetics, is a common remedy for cervical radicular pain and is generally performed under c-arm fluoroscopic guidance, computed tomography (CT), or ultrasound. Interlaminar procedures, such as CESI, typically rely on anteroposterior and lateral (APL) views during needle placement. However, lateral views may be obscured by body habitus in certain individuals. Swimmer's view or contralateral oblique (CLO) view may be used to avoid this.

OBJECTIVE

Our intent was to assess technical success and procedural risk in patients subjected to image-guided CESI procedures with CLO c-arm fluoroscopy.

METHODS

A total of 186 of patients were enrolled and randomly assigned to 1 of 3 groups undergoing image-guided CESI via (1) CT, (2) c-arm fluoroscopy CLO, and (3) c-arm fluoroscopy APL. Complication rates and technical success were assessed, basing the latter on image reviews to confirm the presence of epidural contrast.

RESULTS

All image-guided CESI procedures utilizing CT and CLO fluoroscopy proved technically successful. In the CT group, epidural needle tip and contrast dispersion were clearly visible at all levels of study. In the CLO subset, needle tip visibility was unclear in isolated instances at levels C6-7 and C7-T1 (1 patient each level). In APL procedures, needle tip was regularly obscured by shoulder anatomy at levels C6-7 (26 of 41 patients) and C7-T1 (15 of 16 patients), and contrast dispersion was often uncertain.

CONCLUSION

CLO fluoroscopy-guided CESI is feasible and safe, comparing favorably with CT-guided CESI.

Tract-Specific Diffusion Tensor Imaging in Cervical Spondylotic Myelopathy Before and After Decompressive Spinal Surgery: Preliminary Results

PURPOSE

Diffusion tensor imaging (DTI) metrics of the cervical spinal cord in patients with cervical spondylotic myelopathy (CSM) were compared to those measured in healthy volunteers, using tract-specific region of interests (ROIs) across all cervical intervertebral disc levels.

METHODS

Magnetic resonance (MR) imaging of the cervical spinal cord was performed in four patients with CSM and in five healthy volunteers on a 3-T MR scanner. Region-specific fractional anisotropy (FA) and mean diffusivity (MD) were calculated on axial imaging with ROI placement in the anterior, lateral, and posterior regions of the spinal cord. FA and MD were also calculated on sagittal acquisitions. Nonparametric statistical tests were used to compare controls and patients before and after surgery.

RESULTS

FA values were significantly lower (p = 0.050) and MD values were significantly higher (p = 0.014) in CSM patients measured at level of maximal compression before surgery than in healthy controls in lateral and posterior ROIs, respectively. In posterior ROIs, MD values were significantly higher in patients before surgery compared to controls at all levels except C7-T1.

CONCLUSION

Patients with CSM may demonstrate region-specific changes in DTI metrics when compared to healthy controls. Changes in DTI metrics may also occur at levels remote from site of compression.

Role of a collagen membrane in adhesion prevention strategy for complex spinal surgeries

PURPOSE

Following lumbar spine surgery, postoperative complications can appear, including epidural adhesions. The formation of fibrosis around the dura mater can, on the one hand, lead to compression of the nerve roots with recurrent radicular pain and, on the other hand, can increase the risks of specific complications at spinal re-intervention (haematomas and dural breaches). The aim of this prospective monocentric study was to assess the safety of a new collagen antiadhesion membrane in vertebral osteotomy surgery where scar tissue and adhesions are important.

METHODS

Twenty-six patients consecutively operated for lumbar posterior subtraction osteotomy with implantation of a collagen-based anti-adhesion membrane were evaluated. Membrane tolerance was evaluated at the short and midterm during the regular follow-up.

RESULTS

At six months' follow-up, postoperative pain [visual analogue scale (VAS)] and disability (Oswestry Disability Index score) were significantly reduced 33.1 and 43.1%, respectively. These results were confirmed at 12-months' follow-up, with a decrease in pain of 39.9% and in disability of 49.3%. Amongst the observed postoperative complications was neither spinal fluid leak nor durotomy. Presence of the membrane was not related to complications. Two patients required further surgery for infection and nonunion at the osteotomised level. Adhesions to the dura mater were limited and thin, facilitating exposure.

CONCLUSIONS

This study shows good tolerance of the collagen based membrane for spinal osteotomy and its satisfactory use for preventing postoperative epidural adhesions. Good surgical practice associated with an anti-adhesion barrier may decrease fibrosis formation and improve postoperative functional results.

Clinical Outcomes After Cervical Transcorporeal Microdecompression and Vertebral Body Access Channel Repair

BACKGROUND

Although anterior cervical decompression and fusion (ACDF) can be performed using minimally invasive techniques, the extensive removal of anatomical keystones during decompression requires a segmental fusion to restore biomechanical stability. Treatment with arthrodesis techniques may result in a prolonged recovery time, loss of motion, and the need for further treatment if a pseudarthosis or adjacent segment disease occur. Transcorporeal micro decompression (TCMD) is a newly developed motion sparing, minimally invasive anterior cervical spine decompression procedure that utilizes a small channel through the cervical vertebral body to decompress areas of central or foraminal stenosis while preserving the native disc. Cervical decompression with TCMD can be performed as a stand-alone or hybrid procedure with ACDF at the adjacent levels. This study retrospectively assesses patient based clinical outcome measures in patients treated with TCMD.

METHODS

A retrospective, non-randomized, single-center chart review of single surgeon experience with patients undergoing TCMD both with and without adjacent level ACDF using both a trajectory control guide and access channel repair. Statistical analyses were performed on pre and post-operative data collected using visual analog scale (VAS) and neck disability index (NDI) outcome measures.

RESULTS

Among 62 patients, there were no cases of neurovascular injury, CSF leak, transfusion, or migration of repair implement. Revision surgery was required in 6.4% (n=4) patients. A subanalysis of outcome metrics was performed for patients that underwent standalone TCMD (TCMD group, n=42) and TCMD with concurrent ACDF at one or more levels (TCMD+ACDF group, n=20). TCMD group NDI improved from 20.0 to 2.7 at 1 year (p=0.0001); Axial VAS improved from 5.5 to 0.6 (p=0.0001); and Radiating VAS improved from 7.0 to 0.7 (p=0.0001). TCMD+ACDF group NDI improved from 22.0 to 4.0 at 1 year (p=0.004); Axial VAS improved from 7.1 to 1.2 (p=0.01); and Radiating VAS trended towards significant improvement from 6.4 to 2.3 (p=0.09). Mean return to work was 10 days in the TCMD group and 57 days in the TCMD+ACDF group.

CONCLUSIONS

Within the limits of a retrospective, single-surgeon study, patients did experience both functional improvement and pain relief as measured by NDI and VAS respectively from standalone TCMD or combined ACDF / TCMD procedures. Definitive statements on long-term efficacy, disc space preservation, and motion preservation await further study.

Does improvement in epidurography following percutaneous epidural neuroplasty correspond to patient outcome?

OBJECTIVE

The positive effects of percutaneous epidural neuroplasty (PEN) likely result from elimination of fibrous tissue. However, a direct link between epidural adhesions and pain symptoms is debatable. We tested the hypothesis that epidurographic improvements correspond to improved patient outcome.

METHODS

In this prospective study, patients with a filling defect on initial epidurography underwent PEN. Two weeks later, contrast agent distribution around the target area was assessed with repeat epidurography. A successful treatment was defined as over a 50% reduction in visual analog scale (VAS) score 2 weeks postprocedure. The demographic data, history of lumbar spine operation, target nerve, diagnosis, VAS scores, degree of epidurographic improvement, and patient satisfaction were compared between the successful treatment group (Group I) and unsuccessful treatment group (Group II).

RESULTS

Seventy-nine patients were included. Epidurographic findings improved in 67.1% of patients 2 weeks after the procedure. Following PEN, the mean VAS scores of all patients were significantly decreased at 2 weeks (4.12 ± 2.34), 1 month (3.56 ± 2.30), 3 months (3.84 ± 2.45), and 6 months (4.13 ± 2.71) compared with the initial scores (7.82 ± 1.78). In the comparison between Groups I and II, the rate of epidurographic improvement in Group I was higher than in Group II (P = 0.022). Satisfaction in patients that had epidurographic improvement (median satisfaction: 4) was higher than in patients that did not have epidurographic improvement (median satisfaction: 3; P = 0.003).

CONCLUSION

The epidurographic changes following PEN correlate with patient-assessed pain relief and satisfaction.

A novel balloon-inflatable catheter for percutaneous epidural adhesiolysis and decompression

Epidural adhesions cause pain by interfering with the free movement of the spinal nerves and increasing neural sensitivity as a consequence of neural compression. To remove adhesions and deliver injected drugs to target sites, percutaneous epidural adhesiolysis (PEA) is performed in patients who are unresponsive to conservative treatments. We describe four patients who were treated with a newly developed inflatable balloon catheter for more effective PEA and relief of stenosis. In the present patients, treatments with repetitive epidural steroid injection and/or PEA with the Racz catheter or the NaviCath did not yield long-lasting effects or functional improvements. However, PEA and decompression with the inflatable balloon catheter led to maintenance of pain relief for more than seven months and improvements in the functional status with increases in the walking distance. The present case series suggests that the inflatable balloon catheter may be an effective alternative to performing PEA when conventional methods fail to remove adhesions or sufficiently relieve stenosis.

Spontaneous resorption of lumbar disc herniation is less likely when modic changes are present

STUDY DESIGN

A retrospective survey on 85 consecutive patients with primary single-level lumbar disc herniation (LDH).

OBJECTIVE

To investigate associations between Modic changes (MCs) and the likelihood of resorption of herniated lumbar intervertebral discs.

SUMMARY OF BACKGROUND DATA

Spontaneous resorption of LDH has been demonstrated, whereas the mechanisms are unclear. MCs are closely associated with disc degeneration, but research focusing on their association with spontaneous resorption of LDH has not been specifically investigated.

METHODS

Eighty-five consecutive patients with LDH (52 males, 33 females, aged 20-66 yr) were included. Patients' diagnosis was based on clinical presentation, magnetic resonance imaging, and computed tomography. Patients were divided into surgical and conservative groups and further divided into MC and non-MC subgroups. Spontaneous resorption and clinical success in the conservative group were assessed by reduction in the herniated volume and Oswestry Disability Index. Disc tissues collected from the surgical group were examined histologically, and immunohistochemistry was used to identify endothelial cells and macrophages.

RESULTS

In total, 35 of 85 patients showed MC, mostly type II. Herniated tissue in MC group contained relatively more hyaline cartilage endplate than that in non-MC group (on average, 50% vs. 8%, P < 0.05) but less nucleus pulposus (18% vs. 55%, P < 0.05). Conservative treatment reduced Oswestry Disability Index scores in non-MC group from 29.4 to 23.5 on average (P < 0.05), but reductions in MC group (30.1-29.0) were nonsignificant. Herniated volumes reduced after conservative treatment in non-MC group (0.44-0.21 cm3, P < 0.05) but not in MC group (0.52-0.45 cm3, P > 0.05). More neovascularization and macrophage infiltration was observed in herniated tissue from non-MC group than from MC group (P < 0.001).

CONCLUSION

MCs in patients with LDH are associated with cartilaginous herniations that resorb poorly, so that patients respond less well to conservative treatments. Loss of cartilaginous endplate may explain the origins of MCs and their association with disc infection.

LEVEL OF EVIDENCE

3.

Assessment of effectiveness of percutaneous adhesiolysis and caudal epidural injections in managing post lumbar surgery syndrome: 2-year follow-up of a randomized, controlled trial

Background

The literature is replete with evaluations of failed surgery, illustrating a 9.5%–25% reoperation rate. Speculated causes of post lumbar surgery syndrome include epidural fibrosis, acquired stenosis, recurrent disc herniation, sacroiliac joint pain, and facet joint pain among other causes.

Methods

Patients (n = 120) were randomly assigned to two groups with a 2-year follow-up. Group I (control group, n = 60) received caudal epidural injections with catheterization up to S3 with local anesthetic (lidocaine 2%, 5 mL), nonparticulate betamethasone (6 mg, 1 mL), and 6 mL of 0.9% sodium chloride solution. Group II (intervention group, n = 60) received percutaneous adhesiolysis of the targeted area, with targeted delivery of lidocaine 2% (5 mL), 10% hypertonic sodium chloride solution (6 mL), and nonparticulate betamethasone (6 mg). The multiple outcome measures included the Numeric Rating Scale, the Oswestry Disability Index 2.0, employment status, and opioid intake with assessments at 3, 6, 12, 18, and 24 months posttreatment. Primary outcome was defined as 50% improvement in pain and Oswestry Disability Index scores.

Results

Significant improvement with at least 50% relief with pain and improvement in functional status was illustrated in 82% of patients at the 2-year follow-up in the intervention group compared to 5% in the control group receiving caudal epidural injections. The average number of procedures over a period of 2 years in Group II was 6.4 ± 2.35 with overall total relief of approximately 78 weeks out of 104 weeks.

Conclusion

The results of this study show significant improvement in 82% of patients over a period of 2 years with an average of six to seven procedures of 1-day percutaneous adhesiolysis in patients with failed back surgery syndrome.

A review of the role of epidural percutaneous adhesiolysis

SUMMARY Low back and leg pain can arise for a variety reasons, including epidural scarring caused by post lumbar surgery syndrome, infection or bleeding. Treatment options for low back and/or leg pain caused by epidural scarring include conservative approaches, such as physical therapy and medication management, and procedures, such as epidural steroid injections. Despite appropriate treatment, pain can persist in these patients. Surgery is often not an option for patients whose pain is caused by scarring. Percutaneous adhesiolysis is a minimally invasive technique, which is effective in treating refractory low back and leg pain arising from epidural scarring. It involves the use of a spring-wound, shear-resistant catheter, ideally placed in the ventrolateral aspect of the epidural space for the lysis of adhesions, allowing medications to reach the involved nerve and removing compression of the nerve. After mechanical lysis of adhesions, relatively large volumes of local anesthetic, saline, steroid and radiopaque contrast material are injected. Either hypertonic or normal saline may be used, along with hyaluronidase. After the procedure, the patient should perform exercises to stretch the nerve roots. While this has been studied as a caudal procedure, thoracic and cervical procedures have also been described, using both transforaminal and interlaminar approaches. With trained practitioners, complications are minimal. The effectiveness of the procedure has been documented by high-quality randomized controlled trials and observational studies for both postlumbar surgery syndrome and spinal stenosis.

[Natural history of lumbar disc hernias: does gadolinium enhancement have any prognostic value?]

OBJECTIVES

To evaluate the percentage of disc hernias that have disappeared after one year of follow-up and the time to disappearance. To determine whether gadolinium enhancement is useful for predicting whether the hernia will disappear. To analyze whether the pattern of enhancement can help predict whether the fragment will disappear.

MATERIAL AND METHODS

This prospective study included 118 patients with acute symptoms of lumbosciatica and a herniated disc diagnosed by CT. In 72 patients, we performed gadolinium-enhanced MRI every 6 months for one year or until the herniation disappeared; we related the findings of protrusion, extrusion, and the enhancement pattern with the disappearance or persistence of herniated disc material. We analyzed the results with univariate and multivariate statistics.

RESULTS

The 59% of the hernias disappeared within 1 year of follow-up and 66% disappeared within the first 8 months of follow-up. The 83% of the extruded hernias disappeared, and this was significant in the multivariate analysis (P<.005). The absence of enhancement was significantly associated with the persistence of the hernia in the univariate analysis. The enhancement pattern was not useful for predicting whether the hernia would disappear. Five hernias disappeared within the first two months.

CONCLUSIONS

A high percentage of disc hernias disappear. We found a significant association between extrusion and disappearance but no correlation between the pattern of gadolinium uptake and the disappearance of the hernia.

Fluoroscopic caudal epidural injections in managing post lumbar surgery syndrome: two-year results of a randomized, double-blind, active-control trial

STUDY DESIGN

A randomized, active control, double-blind trial.

OBJECTIVE

To evaluate the effectiveness of fluoroscopically directed caudal epidural injections with or without steroids in managing chronic low back and lower extremity pain secondary to post lumbar surgery syndrome.

SUMMARY OF BACKGROUND DATA

There is a paucity of evidence concerning caudal epidural injections for managing chronic persistent low back pain with or without lower extremity pain caused by post lumbar surgery syndrome.

METHODS

This active control randomized study included 140 patients with 70 patients in each group. Group I received 0.5% lidocaine, 10 mL; Group II received 9 mL of 0.5% lidocaine mixed with 1 mL of 6 mg of nonparticulate betamethasone. The multiple outcome measures included the numeric rating scale, the Oswestry Disability Index 2.0, employment status, and opioid intake with assessments at 3, 6, 12, 18, and 24 months posttreatment. Primary outcome was defined as at least 50% improvement in pain and Oswestry Disability Index scores. Patients with a positive response to the first 2 procedures with at least 3 weeks of relief were considered to be successful. All others were considered as failures.

RESULTS

Overall in Group I, 53% and 47% of the patients and in Group II, 59% and 58% of the patients, showed significant improvement with reduction in pain scores and disability index at 12 months and 24 months. In contrast, in the successful groups, significant pain relief and improvement in function were observed in 70% and 62% of Group I at one and 2 years; in 75% and 69% of Group II at one and 2 years. The results in the successful group showed that at the end of the first year patients experienced approximately 38 weeks of relief and at the end of 2 years Group I had 62 weeks and Group II had 68 weeks of relief. Overall total relief for 2 years was 48 weeks in Group I and 54 weeks in Group II. The average procedures in the successful groups were at 4 in one year and 6 at the end of 2 years.

CONCLUSION

Caudal epidural injections of local anesthetic with or without steroid might be effective in patients with chronic persistent low back and/or lower extremity pain in patients with post lumbar surgery syndrome.

The natural history and clinical syndromes of degenerative cervical spondylosis

Cervical spondylosis is a broad term which describes the age related chronic disc degeneration, which can also affect the cervical vertebrae, the facet and other joints and their associated soft tissue supports. Evidence of spondylitic change is frequently found in many asymptomatic adults. Radiculopathy is a result of intervertebral foramina narrowing. Narrowing of the spinal canal can result in spinal cord compression, ultimately resulting in cervical spondylosis myelopathy. This review article examines the current literature in relation to the cervical spondylosis and describes the three clinical syndromes of axial neck pain, cervical radiculopathy and cervical myelopathy

Pathomechanisms of sciatica in lumbar disc herniation: effect of periradicular adhesive tissue on electrophysiological values by an intraoperative straight leg raising test

STUDY DESIGN

This study is aimed to investigate the changes of nerve root functions during the straight leg raising (SLR) test in vivo.

OBJECTIVE

To investigate the relationship between nerve root movement and the electrophysiological values during an intraoperative SLR test.

SUMMARY OF BACKGROUND DATA

The SLR test is one of the most significant signs for making a clinical diagnosis of lumbar disc herniation. A recent study showed that intraradicular blood flow apparently decreased during the SLR test in patients with disc herniation.

METHODS

The study included 32 patients who underwent microdiscectomy. During the surgery, the nerve root motion affected by the hernia was observed during the SLR test. The patients' legs were allowed to hang down to the angle at which sciatica had occurred and the change of nerve root action potentials was measured. After removal of the hernia, a similar procedure was repeated. The periradicular specimens collected during surgery were examined by light and electron microscope.

RESULTS

In all patients intraoperative microscopy revealed that the hernia was adherent to the dura mater of the nerve roots. During the SLR test, the limitation of nerve root movement occurred by periradicular adhesive tissue and amplitude of action potential showed a sharp decrease at the angle that produced sciatica. After removal of the hernia, all the patients showed smooth gliding of the nerve roots during the test, and there was no marked decrease of amplitude. Our data suggest that temporary ischemic changes in the nerve root cause transient conduction disturbances. Pathologic examination showed that the periradicular tissue consisted of the granulation with vascularization and many inflammatory cell infiltrations.

CONCLUSION

The presence of periradicular fibrosis will compound the nerve root pain by fixing the nerve in one position, thereby increasing the susceptibility of the nerve root to tension or compression.

Changes in blood flow, oxygen tension, action potentials, and vascular permeability induced by arterial ischemia or venous congestion on the lumbar dorsal root ganglia in dogs

It is generally believed that radiculopathy associated with the degenerative conditions of the spine may result from both mechanical compression and circulatory disturbance. However, the basic pathophysiology of circulatory disturbance induced by ischemia and congestion is not fully understood. This study investigated the effect of ischemia and congestion on the dorsal root ganglion (DRG) using an in vivo model. The sixth and seventh lumbar laminae were removed and the seventh lumbar DRG was exposed using adult dogs. The aorta was clamped as an ischemic model in the DRG, and the inferior vena cava was clamped as a congestion model at the sixth costal level for 30 min using forceps transpleurally. Measurements of blood flow, partial oxygen pressure, and action potentials in the DRG were recorded over a period of 1 h after clamp release. Finally, we examined the status of intraganglionic blood permeability under a fluorescence microscope following injection of Evans blue albumin into the cephalic vein to determine the type of circulatory disturbance occurring in the DRG. Immediately after inferior vena cava clamping, the central venous pressure increased approximately four times and marked extravasation of protein tracers was induced in the lumbar DRG. Blood flow, partial oxygen pressures, and action potentials within the DRG were more severely affected by the aorta clamping; however, this ischemic model did not reveal any permeability changes in the DRG. The permeability change in the DRG was more easily increased via venous congestion than by arterial ischemia. The intraganglionic venous flow was stopped with compression at much lower pressures than that needed to impact arterial flow. From a clinical perspective, intraganglionic edema formation, rather than arterial ischemia, may be an earlier phenomenon inducing DRG dysfunction.

Effects of arterial ischemia and venous congestion on the lumbar nerve root in dogs

The development of radiculopathy in patients with lumbar canal stenosis is thought to be closely related to intraradicular edema resulting from compression. However, there is little agreement as to question which is more essential for intermittent claudication: ischemia or congestion. The aim of the present experimental investigation was to examine the effect of ischemia and congestion on the nerve root using dogs. The aorta was clamped as an ischemia model of the nerve root and the inferior vena cava was clamped as a congestion model at the sixth costal level for 30 min using forceps transpleurally. Measurements of blood flow, partial oxygen pressure, and conduction velocity in the nerve root were repeated over a period of 1 h after release of clamping. Finally, we examined the status of intraradicular blood-nerve barrier under fluorescence and transmission electron microscope. Immediately after clamping of the inferior vena cava, the central venous pressure increased by about four times and marked extravasation of protein tracers was induced in the lumbar nerve root. Blood flow, partial oxygen pressure, and conduction velocity of the nerve root were more severely affected by aorta clamp, but this ischemia model did not show any intraradicular edema. The blood-nerve barrier in the nerve root was more easily broken by venous congestion than by arterial ishemia. In conclusion, venous congestion may be an essential factor precipitating circulatory disturbance in compressed nerve roots and inducing neurogenic intermittent claudication.

Elevated levels of tumor necrosis factor-alpha in periradicular fat tissue in patients with radiculopathy from herniated disc

STUDY DESIGN

Case-control study.

OBJECTIVE

To determine whether inflammatory cytokines [tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6 and IL-8] are elevated in tissues intimately surrounding involved nerve roots of patients suffering from radiculopathy form herniated disc (HD).

SUMMARY OF BACKGROUND DATA

Proinflammatory cytokines are postulated to play an important role in radiculopathy from HD. Although TNF-alpha has been found in human HD, it is not known whether TNF-alpha concentrations are increased in symptomatic patients. Epidural fat (EF) is another tissue in close contact with nerve roots. Histologic modifications of EF have been reported in patients with sciatica but concentrations of inflammatory cytokines have never been studied.

METHODS

Twenty-three lumbar HD along with adjacent EF (EFHD) were harvested from patients with radicular syndrome. As controls, 14 intervertebral discs (IVDs) and 10 samples of EF (EFC) were obtained from patients without radicular syndrome undergoing spine surgery. Tissue explants were incubated ex vivo for 48 hours and the concentrations of cytokines were measured by elisa in the supernatants. Results were standardized according to tissue weight.

RESULTS

All 4 cytokines were found at higher concentrations in EFHD compared with HD (P < 0.001). TNF-alpha was the only cytokine found in significantly higher levels in EFHD compared with EFC [median, interquartile range 6.6, (1.6-16.3) pg/mL per milligram of tissue vs. 2.3 (1.3-5.0), P < 0.05] and to subcutaneous fat [0.35 (0-2.28), P < 0.001]. No significant increase of either cytokines was found in HD compared with IVD.

CONCLUSION

Higher concentrations of TNF-alpha were found in EF from patients with radiculopathy from HD compared with patients suffering from other type of back pain. These results support the role of TNF-alpha in the pathogenesis of radiculopathy from HD.

Temporo-spatial distribution of blood vessels in human lumbar intervertebral discs

While there is consensus in the literature that blood vessels are confined to the outer anulus fibrosus of normal adult intervertebral disc, debate continues whether there is a vascular in-growths into inner parts of the intervertebral disc during degeneration. We therefore tested the hypothesis that vascular in-growth is not a distinct feature of disc degeneration. The specific endothelial cell marker CD 31 (PECAM) was used to immunohistochemically investigate 42 paraffin-embedded complete mid-sagittal human intervertebral disc sections of various ages (0-86 years) and varying extent of histomorphological degeneration. Additionally, 20 surgical disc samples from individuals (26-69 years) were included in this study. In discs of fetal to infantile age, blood vessels perforated the cartilaginous end plate and extended into the inner and outer anulus fibrosus, but not into the nucleus pulposus. In adolescents and adults, no blood vessels were seen except for the outer zone of the anulus fibrosus adjacent to the insertion to ligaments. The cartilaginous end plate remained free of vessels, except for areas with circumscribed destruction of the end plate. In advanced disc degeneration, no vessels were observed except for those few cases with complete, scar-like disc destruction. However, some rim lesions and occasionally major clefts were surrounded by a small network of capillary blood vessels extending into deeper zones of the anulus fibrosus. A subsequent morphometric analysis, revealed slightly "deeper" blood vessel extension in juvenile/adolescent discs when compared to young, mature and senile adult individuals with significantly "deeper" extension in the posterior than anterior anulus. The analysis of the surgical specimens showed that only sparse capillary blood vessels which did not extend into the nucleus pulposus even in major disc disruption. Our results show that vascular invasion deeper than the periphery was not observed during disc degeneration, which supports the hypothesis that vascular in-growth is not a distinct feature of disc degeneration.

A nonsurgical approach to the management of patients with cervical radiculopathy: a prospective observational cohort study

OBJECTIVE

The objective of this study was to describe the clinical outcomes of patients with cervical radiculopathy (CR) treated nonsurgically after a diagnosis-based decision rule.

METHODS

A prospective observational cohort study on consecutive patients with CR was performed. Data on 35 consecutive patients were collected at baseline, at the end of the active treatment, and at a minimum of 3 months after cessation of treatment. Disability was measured using the Bournemouth Disability Questionnaire. Pain intensity was measured using the Numerical Pain Rating Scale. Patients were also asked to self-rate their improvement.

RESULTS

Complete outcome data were available for 31 of the 35 patients. Twenty-seven patients were reached for long-term follow-up. The mean number of months from last treatment to follow-up was 8.2 months. Seventeen patients (49%) reported their improvement as "excellent" and another 14 (40%) did so as "good." The mean patient-rated improvement was 88.2%. The mean percentage of improvement in the Bournemouth Disability Questionnaire score was 78%. The mean percentage of improvement in the Numerical Pain Rating Scale score was 72%. Twenty-four of 31 (77.4%) patients had a clinically significant improvement from baseline to the end of treatment, and 25 of 27 (92.6%) had a clinically significant improvement from baseline to long-term follow-up.

CONCLUSIONS

The management strategy that we studied yielded favorable outcomes in this patient sample and appears to be a safe option for patients with CR. However, the absence of randomization and a control group limits interpretation with regard to clinical effectiveness. Randomized clinical trials are necessary to distinguish treatment effects from the natural history of CR.

Cellular therapy for disc degeneration

STUDY DESIGN

Review article regarding the developing field of cellular therapies for symptomatic disc degeneration.

OBJECTIVE

To review the rationale and discuss the results of cellular strategies that have been proposed or investigated for disc degeneration.

SUMMARY OF BACKGROUND DATA

Disc degeneration is a substantial clinical problem. Disc degeneration begins with a loss of disc cells and alterations in the extracellular matrix of the disc. One promising approach for this problem involves the use of cells transplanted to the degenerative disc to achieve functional tissue repair.

METHODS

The rationale for using cellular therapy for disc degeneration is discussed. The basic science studies involving cellular transplantation to the disc are reviewed and future directions of this line of research are discussed.

RESULTS

Although substantial work remains, the future of cellular therapies for symptomatic disc degeneration appears promising.

CONCLUSION

Continued research is warranted to further define the optimal cell type, scaffolds, and adjuvants that will allow successful disc repair in human patients.

[ISRCTN 16558617] A randomized, controlled trial of spinal endoscopic adhesiolysis in chronic refractory low back and lower extremity pain

BACKGROUND

Postoperative epidural fibrosis may contribute to between 5% to 60% of the poor surgical outcomes following decompressive surgery. Correlations have been reported between epidural scarring and radicular pain, poor surgical outcomes, and a lack of any form of surgical treatment. The use of spinal endoscopic adhesiolysis in recent years in the management of chronic refractory low back and lower extremity pain has been described.

METHODS

A prospective, randomized, double-blind trial was conducted to determine the outcome of spinal endoscopic adhesiolysis to reduce pain and improve function and psychological status in patients with chronic refractory low back and lower extremity pain. A total of 83 patients were evaluated, with 33 patients in Group I and 50 patients in Group II. Group I served as the control, with endoscopy into the sacral level without adhesiolysis, followed by injection of local anesthetic and steroid. Group II received spinal endoscopic adhesiolysis, followed by injection of local anesthetic and steroid.

RESULTS

Among the 50 patients in the treatment group receiving spinal endoscopic adhesiolysis, significant improvement without adverse effects was shown in 80% at 3 months, 56% at 6 months, and 48% at 12 months. The control group showed improvement in 33% of the patients at one month and none thereafter. Based on the definition that less than 6 months of relief is considered short-term and longer than 6 months of relief is considered long-term, a significant number of patients obtained long-term relief with improvement in pain, functional status, and psychological status.

CONCLUSION

Spinal endoscopic adhesiolysis with targeted delivery of local anesthetic and steroid is an effective treatment in a significant number of patients with chronic low back and lower extremity pain without major adverse effects.

New treatment of lumbar disc herniation involving 5-hydroxytryptamine2A receptor inhibitor: a randomized controlled trial

OBJECT

Serotonin or 5-hydroxytryptamine (5-HT) is a chemical mediator associated with nucleus pulposus-induced radiculopathy. Inhibition of 5-HT receptors may potentially alleviate symptoms in patients with lumbar disc herniation. This prospective randomized controlled study was performed to evaluate the efficacy of the 5-HT2A receptor inhibitor in the treatment of symptomatic lumbar disc herniation.

METHODS

Forty patients with sciatica due to L4-5 or L5-S1 disc herniation were randomly allocated to treatment with the 5-HT2A inhibitor (sarpogrelate 300 mg/day) or nonsteroidal antiinflammatory drugs (NSAIDs; diclofenac 75 mg/day). Low-back pain, leg pain, and numbness were evaluated using a visual analog scale (VAS) before and after a 2-week course of treatment. The patients received only allocated medicine during the 2-week regimen and were thereafter allowed to choose any treatment options depending on their residual symptoms. One-year clinical outcomes were assessed based on the rates of additional medical interventions. The mean VAS score improvements in the 5-HT2A and NSAID groups were 33 and 46% for low-back pain, 32 and 32% for leg pain, and 35 and 22% for leg numbness, respectively. After the 2-week regimen, no additional medical interventions were required in 50% of 5-HT2A-treated patients and 15% of those receiving NSAIDs. Epidural or nerve root block procedures were performed in 35% of the 5-HT2A group and 45% of the NSAID group. Surgery was required in 20% of the 5-HT2A group and 30% of the NSAID group patients.

CONCLUSIONS

The current study provided evidence that the efficacy of the 5-HT2A inhibitor was comparable with that of NSAID therapy for lumbar disc herniation. The 5-HT2A inhibitor has the potential to alleviate symptoms in patients with lumbar disc herniation.

Physiological and behavioral evidence for focal nociception induced by epidural glutamate infusion in rats

STUDY DESIGN

Blinded animal study.

OBJECTIVES

To determine if an increased concentration of epidural glutamate can cause a focal nociceptive response in the lower extremities that is consistent with sciatica.

SUMMARY OF BACKGROUND DATA

It is believed that the origin of sciatic pain is related to more than physical pressure on the nerve roots. Recently, it was determined that disc material may be a significant source of free glutamate, resulting from the enzymatic degradation of matrix aggrecan proteins. We believe that this free glutamate acts as a neurotransmitter at glutamate receptors on the dorsal root ganglion (DRG) cell bodies, thereby initiating a nociceptive response.

METHODS

Rats were subject to a 72-hour epidural glutamate infusion via a mini osmotic pump. Von Frey behavioral testing was performed 24 hours before, and 24 and 72 hours after the onset of the infusion. DRG and dorsal horn tissues were analyzed for changes in receptor expression, which have been previously shown to correlate with a nociceptive state.

RESULTS

Von Frey behavioral tests showed focal hyperalgesia that was maximal at the 0.02 mmol/L glutamate concentration. Significant changes in DRG glutamate receptor expression were seen for alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid, kainite, and N-methyl-D aspartate receptors. Analysis of dorsal horn glutamate receptors also showed patterns in alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid and kainate receptor expression that were consistent with a nociceptive state.

CONCLUSIONS

Epidural glutamate elicits a focal nociceptive response. Free glutamate that has been liberated from the disc material may be an important factor in the development of sciatic pain.

Apparent diffusion coefficient and fractional anisotropy in spinal cord: Age and cervical spondylosis-related changes

PURPOSE

To present the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) change with age in the normal spinal cord and in cervical spondylosis.

MATERIALS AND METHODS

A total of 11 normal volunteers and 79 cervical spondylosis patients entered this study. Line scan diffusion tensor images were obtained in a 1.5-Tesla whole-body scanner using a phased-array spine coil. The ADC and FA values were measured on a sagittal section. Spearman correlation of ADC/FA vs. age for normal spinal cord was calculated.

RESULTS

The mean ADC of the normal spinal cord was 0.81 +/- 0.03 microm(2)/msec at the relatively wide C2-C3 level and 0.75 +/- 0.06 microm(2)/msec at the more narrow C4-C7 level. The FA at the corresponding level was 0.70 +/- 0.05 and 0.66 +/- 0.03, respectively. With age, ADC showed positive correlation (Spearman, r = 0.242) and FA exhibited negative correlation (Spearman, r = -0.244). A total of 54% of all spondylosis cases showed elevated ADC (P < 0.001) and decreased FA (P < 0.001) at the stenotic spinal canal level compared with the normal spinal cord. The average ADC and FA of high-signal lesions on T2-weighted images (seven patients) were 1.28 +/- 0.33 microm(2)/msec and 0.46 +/- 0.12, respectively.

CONCLUSION

ADC increases and FA decreases with age in the normal spinal cord. Elevated ADC and reduced FA were measured in the spinal cord of spondylosis cases with clinical symptoms of myelopathy.

Distribution and appearance of tumor necrosis factor-alpha in the dorsal root ganglion exposed to experimental disc herniation in rats

STUDY DESIGN

Distribution and appearance of tumor necrosis factor-alpha (TNF-alpha) in the dorsal root ganglion (DRG) exposed to experimental disc herniation were investigated using an immunohistochemical method in rats.

OBJECTIVES

To study the distribution and appearance of TNF-alpha in the DRG following experimental disc herniation in rats.

SUMMARY OF BACKGROUND DATA

Nucleus pulposus in the epidural space induces spinal nerve root injury not only by mechanical but also chemical mechanisms. Cytokines may play a key role in the chemical damage. There is, however, no report on the distribution and appearance of TNF-alpha in the DRG exposed to nucleus pulposus.

METHODS

Nucleus pulposus from the discs was smeared on the glass slides and processed for immunohistochemistry by the avidin-biotinylated peroxidase complex technique using rabbit antisera to TNF-alpha in rats. A herniation of the nucleus pulposus was made by incision of the L4-L5 disc in rats. The L4 and L5 DRGs were resected 1, 3, 7, 14, and 21 days after surgery. The specimens were processed for immunohistochemistry using rabbit antisera to TNF-alpha. The TNF-alpha-positive cells were observed and counted using light microscopy. Distribution of the TNF-alpha products was compared on each day after surgery.

RESULTS

A positive staining was seen in the cell bodies and in the matrix between the cells in the smeared nucleus pulposus. In the L4 DRG sections, the number of positive cells was significantly higher in the disc incision group than in the sham group at 1, 3, 7, and 14 days after surgery (P < 0.05). The positive cells showed a decrease in number day by day after surgery. On the contrary, in the L5 DRG, only a few positive cells were observed in the disc incision group after surgery. There was no statistically significant difference between disc incision and the sham groups at each day after surgery for the L5 DRGs.

CONCLUSIONS

The immunoreactivity of TNF-alpha in the DRG directly exposed to nucleus pulposus increases during 2 weeks. A collapse of the positive cells was seen in the DRG directly exposed to the nucleus pulposus.

Lumbar disk herniation: correlation of histologic findings with marrow signal intensity changes in vertebral endplates at MR imaging

PURPOSE

To compare findings at preoperative magnetic resonance (MR) imaging with data for tissue composition of herniated disks in patients after microsurgical removal of herniated material.

MATERIALS AND METHODS

Fifty-one patients underwent MR imaging before microsurgical removal of extruded lumbar disk herniation material. Marrow signal intensity changes along the cartilaginous endplates were classified according to Modic types 1-3. Severity of changes was evaluated with respect to extension along the endplate in the anteroposterior diameter (0%, <33%, 33%-66%, >66%). The existence of a dorsal vertebral corner defect was evaluated in relation to the existence of hyaline cartilage in the disk extrusion material.

RESULTS

Mean tissue composition of herniated material in all patients was 63% anulus fibrosus, 30% nucleus pulposus, and 8% cartilaginous endplate. Twenty-five of the 51 patients had hyaline cartilaginous material in the extrusion (range, 5%-50%). Patients without marrow signal intensity changes along the cartilaginous endplate showed significantly less cartilaginous material in the extruded disk (P =.023, Fisher exact test). Mean percentage hyaline cartilage in patients without changes was 2% +/- 4 (SD) (Modic type 1, 16% +/- 15; type 2, 10% +/- 12). When the changes extended 33% of the vertebral endplate, there was cartilaginous endplate material in the extruded disk (P =.006). Cartilage from the endplate was present in the extruded disk material in 40% (16 of 40) of patients without a vertebral corner defect and in 82% (nine of 11) of patients with a vertebral corner defect (P =.019).

CONCLUSION

Avulsion-type disk herniation seems to be common, and vertebral endplate marrow signal intensity changes on MR images are indicative of cartilaginous material in the extruded disk herniation material.

Proximal neuromuscular impairment in lumbar disc herniation: a prospective controlled study

STUDY DESIGN

A prospective and controlled study investigated the relation of muscle dysfunction to residual pain and disability in patients with lumbar disc herniation.

OBJECTIVES

To determine the incidence of lower limb muscle dysfunction in lumbar disc herniation and its evolution over time after surgery, and to ascertain whether neuromuscular dysfunction has a prognostic value regarding pain and disability.

SUMMARY OF BACKGROUND DATA

Residual sciatica, low back pain, and disability are common after lumbar discectomy. Preoperative motor dysfunction corresponding to the afflicted nerve root is often seen.

METHODS

The participants in this study were 71 patients, ages 15 to 50 years, with disc prolapse at L4-L5 or L5-S1. Before surgery, then 6 weeks, 4 months, and 12 months after surgery, low back pain and leg pain were estimated on a visual analog scale, and disability was determined according to the Roland-Morris Questionnaire and a designed functional muscle test.

RESULTS

Motor function of the sciatic leg frequently was impaired. Inferior outcome of proximal motor tests 6 weeks after surgery predicted pain and disability 1 year after surgery. The mean leg pain was 59 mm before surgery and 15 mm at 6 weeks, remaining at that level during the follow-up period. The mean disability score was 14.4 before surgery, 8.8 at 6 weeks, and 4.7 at 4 and 12 months, whereas muscle function improved gradually through 1 year of follow-up evaluation.

CONCLUSIONS

Neuromuscular dysfunction frequently is present in patients with lumbar disc herniation. Sciatica resolves quickly after surgery, whereas disability improves gradually up to 4 months and muscular performance improves throughout the first year. Proximal muscular dysfunction in lumbar disc herniation has a prognostic value concerning residual pain and disability.

Efficacy of serotonin receptor blocker for symptomatic lumbar disc herniation

Serotonin is one of the chemical mediators associated with nerve root inflammation and sciatic symptoms in lumbar disc herniation. The efficacy of serotonin 5-HT(2A) receptor blocker was examined in 44 patients with symptomatic lumbar disc herniation. A selective 5-HT(2A) receptor blocker (sarpogrelate hydroxychloride) was administered orally at a dose of 300 mg per day for 2 weeks. Visual analog scales of low back pain, sciatic pain, and numbness were significantly improved after the administration of the serotonin 5-HT(2A) receptor blocker. Clinical results were good (> 50% pain relief) in 23 patients, fair (25%-50% pain relief) in five patients, and poor (< 25% of pain relief) in 16 patients. Nineteen patients eventually required surgery because of muscle weakness or cauda equina symptoms. The effect of 5-HT(2A) blocker was good in 64% of patients who had uncontained disc herniation, whereas all patients with contained disc herniation had fair or poor results. Patients with uncontained disc herniation responded more favorably to the 5-HT(2A) blocker treatment than patients with contained disc herniation. A 5-HT(2A) blocker has the potential to block the cascade of acute nerve root inflammation and to alleviate symptoms in lumbar disc herniation.

Epidural lysis of adhesions and myeloscopy

Chronic low back pain is one of the most common ailments in modern medicine, with as many as 79% of patients with acute pain continuing to suffer with chronic or recurrent low back pain 1 year after its onset. Lumbar epidural fibrosis and post-lumbar laminectomy syndrome are increasingly recognized as being responsible for persistent low back pain. Estimations show that approximately 5% to 40% of lumbar surgeries result in failed back surgery syndrome. Epidural adhesiolysis with myeloscopy is an interventional technique based on the premise that the three-dimensional visualization of the contents of the epidural space provides the physician with the ability to directly visualize the structures, perform appropriate adhesiolysis, and administer drugs specifically to the target. This review describes pathophysiologic aspects, purposes and goals, rationale and indications, complications, and effectiveness of epidural lysis of adhesions with myeloscopy.

Indications for and benefits of lumbar facet joint block: analysis of 230 consecutive patients

Object

The authors evaluated the effectiveness of using a facet joint block with local anesthetic agents and or steroid medication for the treatment of low-back pain in a medium-sized series of patients.

Methods

Over a period of 4 years, the authors performed 715 facet joint injections in 230 patients with variable-length histories of low-back pain. The main parameter for the success or failure of this treatment was the relief of the pain. For the first injection—mainly a diagnostic procedure—the authors used a local anesthetic (1 ml bupivacaine 1%). In cases of good response, betamethasone was injected in a second session to achieve a longer-lasting effect.

Long-lasting relief of the low-back pain and/or leg pain was reported by 43 patients (18.7%) during a mean follow-up period of 10 months. Thirty-five patients (15.2%) noticed a general improvement in their pain. Twenty-seven patients (11.7%) reported relief of low-back pain but not leg pain. Nine patients (3.9%) suffered no back pain but still leg pain. One hundred sixteen patients (50.4%), however, experienced no improvement of pain at all. In two cases the procedure had to be interrupted because of severe pain. There were no cases of infection or hematoma.

Conclusions

Lumbar facet joint block is a minimally invasive procedure to differentiate between facet joint pain and other causes of lower-back pain. The procedure seems to be useful for distinguishing between facet joint pain from postoperative pain due to inappropriate neural decompression after lumbar surgery. It can be also recommended as a possible midterm intervention for chronic low-back pain.

[Spinal epidural fibrosis following lumbar diskectomy and antiadhesion barrier]

Although diskectomy after hemilaminectomy always produces some fibrosis, only few patients develop clinical symptoms. Fibrosis is one of the causes for failed lumbar disc surgery. Identification of fibrosis as the cause of recurring lumbar or sciatic pain requires the existence of a good clinical history and selective physical examination of the patient. MR is the imaging technique of choice although CT and myelography can be useful in some cases. Surgery can correct recurrent hernias, segmentary instability or spinal stenosis, but good results are less likely in patients with epidural fibrosis. When this exists, surgery should be directed to performing an arthrodesis of the vertebral space since the operation itself can destabilize the segment resulting in instability of the affected segment. Application of ADCON-L did not worse and in some cases improved the clinical condition of patients in double blind studies. Our multicentric double blind study showed no clinical differences among 253 patients at six months after surgery. Additionally, since this gel seems to avoid the development of fibrosis, it may prevent one of the main causes of failed disc surgery and, if reoperation is necessary due to disc remains or a lateral stenosis, the absence of fibrosis would facilitate surgery.

Role of leukocytes in radicular pain secondary to herniated nucleus pulposus

Some studies have assessed inflammatory cells such as macrophages, lymphocytes, and neutrophils in herniated lumbar disc tissues using histologic analysis. However, there is no consensus regarding the relationships between clinical symptoms, including radicular pain and the presence of inflammatory cells. It has been shown that autologous nucleus pulposus relocated on the lumbar nerve root in rats produces time dependent and reversible mechanical hyperalgesia, which is thought to be a pain related behavior in peripheral neuropathic pain models. The purpose of this study was to determine whether leukocytes play a role in the mechanical hyperalgesia induced by the nucleus pulposus and to characterize the role of leukocytes in radicular pain attributable to lumbar disc herniation. Nitrogen mustard was used to induce and evaluate leukocytopenia in rats. Sensitivity to mechanical noxious stimuli was measured quantitatively, and inflammatory cells in granulation tissue around the nerve root were examined histologically. The nucleus pulposus produced neither mechanical hyperalgesia nor abundant inflammatory cells in rats with nitrogen mustard induced leukocytopenia. Neuropathic pain produced by the nucleus pulposus, when placed on the nerve root, may be related to inflammatory cell infiltration induced by relocation of the nucleus pulposus, rather than the nucleus pulposus itself.