Epidural Scar Research Articles

Spinal Cord Stimulation in a Patient with Spinal Epidural Lipomatosis

Spinal cord stimulation is the most commonly used implantable neurostimulation modality for management of pain syndromes. For treatment of lower extremity pain, the spinal cord stimulator lead is typically placed in the thoracic epidural space, at the T10-T12 levels. Typically, satisfactory stimulation can be obtained relatively easily. Anatomical variability in the epidural space, such as epidural scarring, has been reported to prevent successful implantation of spinal cord stimulators. Spinal epidural lipomatosis describes an abnormal overgrowth of adipose tissue in the extradural space. Cases have documented spinal epidural lipomatosis complicating intrathecal baclofen pump implantation or causing repeated failure of epidural analgesia. However, so far, there is no published literature describing how spinal epidural lipomatosis affects spinal cord stimulation. We report a case of spinal cord stimulation in a patient with spinal epidural lipomatosis. Very high impedance was encountered during the trial spinal cord stimulator lead placement. Satisfactory stimulation was only obtained after repeated repositioning of the spinal cord stimulator trial lead. Post-procedure thoracic spine magnetic resonance imaging revealed marked thoracic epidural lipomatosis. At the level where satisfactory stimulation was obtained, the thickness of the epidural fat was within normal limits. The patient eventually underwent placement of a laminotomy lead with good coverage and pain relief. Spinal epidural lipomatosis significantly increases the impedance in the epidural space, making effective neurostimulation very difficult to obtain. Physicians should consider the possibility of spinal epidural lipomatosis when very high impedances are encountered during lead placement.

The effect of methylene blue on peridural fibrosis formation after laminectomy in rats: an experimental novel study

Background context Despite progress in surgical techniques, some patients still face postoperative recurrence of pain, although the rate of successful outcomes is estimated to be approximately 70% and 86% after primary decompression spinal surgery. Recently, attention has been focused on peridural fibrosis (PF), which may be responsible for recurrent pain after laminectomy or discectomy. Methylene blue (MB) has been shown to prevent fibrosis formation in various tissues. Purpose The aims of this study were to investigate the effects of MB and assess the effects of different doses on the prevention of postlaminectomy fibrosis formation in a rat model. This preclinical model is a potential platform for future clinical trials to identify an effective agent for the prevention of clinically important epidural scar formation. Study design An established bilateral L5–L6 rat laminectomy model was used to evaluate postlaminectomy PF with macroscopic and microscopic analyses. Patient sample Seventy-five male adult white Sprague-Dawley rats that underwent laminectomy at the L5–L6 levels were divided into five groups of 15 rats each. Outcome measures Dissected specimens were evaluated macroscopically and microscopically by examiners who were unaware of the group assignment to record the presence or absence of PF formation. Methods Groups A and B served as controls and Groups C, D, and E received treatment. Group A (sham) underwent laminectomy, and Group B was treated with normal saline at the laminectomy site. Rats in Groups C, D, and E received 0.1 mL MB at concentrations of 0.5%, 1%, and 2%, respectively, at the laminectomy site. All rats were killed 4 weeks after laminectomy. The results were compared statistically with the nonparametric Kruskal–Wallis test and Poisson regression. Results Peridural fibrosis was found in five rats (33%) in control Groups A and B and in two rats (10%) in MB-treated laminectomy Groups C and D. The difference between control and MB groups was not statistically significant (p=.27). The preventive effect of MB on PF was not seen at the highest dose of MB (2%) in Group E. Severity of fibrosis was lower in Groups C (MB 0.5%) and D (MB 1%) than in Group E (MB 2%) (p<.01). Wound healing was not affected, and there was no cerebrospinal fluid leakage. No neurological deficits were seen. Conclusion Low doses of MB may be an effective agent in preventing PF formation after lumbar laminectomy in rats. Clinical significance and safety in human use are currently undetermined.

Preparation and characterization of a new gellan gum and sulphated hyaluronic acid hydrogel designed for epidural scar prevention

Postsurgical adhesions are a common problem in clinical practice, causing nerve compression, pain and discomfort. A new hydrogel based on gellan gum and sulphated hyaluronic acid was synthesized, with the aim to create an effective barrier for epidural scar formation. Physico-chemical properties of the gel were analyzed, and preliminary biocompatibility data (i.e. cytotoxicity) have been collected in view of its potential clinical use. The characterization of the new material demonstrated that the hydrogel, due to its high-viscosity, could effectively act as a barrier with a long in situ residence time. In addition, the hydrogel can be easily extruded from a syringe and its structure exhibits excellent stabilizing properties. Furthermore, biological assays showed that this gel is suitable for further preclinical development.

Inhibition Of Tumor Necrosis Factor May Improve Wound Healing And Reduce Scar Formation Following Laminectomy. A Pilot Study In Pigs.

In rats treated with a selective TNF-inhibitor it was accidentally found that wound healing was improved and scar/adhesion formation was reduced. The present pilot study was performed to evaluate if this could be repeated in a controlled setting using a laminectomy model in the pig. Following anesthesia a laminectomy of all sacral vertebrae was performed in 6 pigs. Three pigs were treated with infliximab (a selective TNF inhibitor) and three pigs received saline and served as control. After 7 days the laminectomy site was evaluated by a macroscopical analysis and specimens of skin and muscle tissue over the laminectomy were processed for histology. Skin, fascia, muscle and bone healing was remarkably better in the pigs treated with infliximab. In pigs treated with infliximab there were signs of a partial healing of the laminectomy defect and in the centre of the defect there was a gel-like tissue that allowed for observation of the underlying nervous tissues. The laminectomy defect in saline treated animals had less bone formation and a soft scar in the centre of the defect. The present pilot investigation may thus indicate that an inhibition of pro-inflammatory cytokines may increase wound-healing rate and reduce scar formation/adhesion. However, further studies that evaluate exact mechanisms, when and how long to use anti-inflammatory treatment, long term effects, wound quality, risks for infection, if this may be translated to humans, must be undertaken before any conclusions regarding a clinical use may be drawn. The study nevertheless implies that it might be possible to develop a biological agent that alone or in combination with a mechanical barrier may reduce epidural scarring following spinal surgery.

Endoscopic discectomy of L5-S1 disc herniation via an interlaminar approach: Prospective controlled study under local and general anesthesia

Background:Open discectomy remains the standard method for treatment of lumbar disc herniation, but can traumatize spinal structure and leaves symptomatic epidural scarring in more than 10% of cases. The usual transforaminal approach may be associated with difficulty reaching the epidural space due to anatomical peculiarities at the L5–S1 level. The endoscopic interlaminar approach can provide a direct pathway for decompression of disc herniation at the L5–S1 level. This study aimed to evaluate the clinical results of endoscopic interlaminar lumbar discectomy at the L5–S1 level and compare the technique feasibility, safety, and efficacy under local and general anesthesia (LA and GA, respectively).Methods:One hundred twenty-three patients with L5–S1 disc herniation underwent endoscopic interlaminar lumbar discectomy from October 2006 to June 2009 by two spine surgeons using different anesthesia preferences in two medical centers. Visual analog scale (VAS) scores for back pain and leg pain and Oswestry Disability Index (ODI) sores were recorded preoperatively, and at 3, 6, and 12 months postoperatively. Results were compared to evaluate the technique feasibility, safety, and efficacy under LA and GA.Results:VAS scores for back pain and leg pain and ODI revealed statistically significant improvement when they were compared with preoperative values. Mean hospital stay was statistically shorter in the LA group. Complications included one case of dural tear with rootlet injury and three cases of recurrence within 1 month who subsequently required open surgery or endoscopic interlaminar lumbar discectomy. There were no medical or infectious complications in either group.Conclusion:Disc herniation at the L5–S1 level can be adequately treated endoscopically with an interlaminar approach. GA and LA are both effective for this procedure. However, LA is better than GA in our opinion.

Paraspinal Abscess after Percutaneous Adhesiolysis

Permanent pain after surgical approach for lumbar pathology may due to epidural scarring. However, surgical approach could not relieve the pain in all cases. Percutaneous adhesiolysis might be a valuable technique in managing chronic pain caused by epidural scarring. Following the percutaneous adhesiolysis, it has been reported that several complications such as dural puncture, intravascular injection, but abscess formation in the paraspinal muscles immediately after the adhesiolysis is the first case in literature.

Recurrent Lumbar Disk Herniation

Recurrent lumbar disk herniation is the most common complication following primary open diskectomy. It is defined as recurrent back and/or leg pain after a definite pain-free period lasting at least 6 months from initial surgery. Careful neurologic examination is critical, and laboratory tests should be ordered to evaluate for infection. Imaging demonstrates disk herniation at the previously operated level. It is important to differentiate recurrent disk herniation from postoperative epidural scar because the latter may not benefit from reoperation. Treatment of recurrent lumbar disk herniation includes aggressive medical management and surgical intervention. Surgical techniques include conventional open diskectomy, minimally invasive open diskectomy, and open diskectomy with fusion. Fusion is necessary in the presence of concomitant segmental instability or significant foraminal stenosis resulting from disk space collapse.

Application of a new hydrogel dural sealant that reduces epidural adhesion formation: evaluation in a large animal laminectomy model

The aim of this study was to evaluate the application and effects of a novel, nonswelling, polyethylene glycol-based hydrogel adhesion barrier and sealant in a canine laminectomy model of CSF leakage and adhesion formation. After full-width L-2 and L-5 laminectomies, 1-cm midline durotomies were created and sutured closed, except for the last 1-2 mm on the cranial end to create spontaneous CSF leakage. All 5 control animals received no further treatment. Experimental animals received hydrogel at both durotomy sites via either the Dual Liquid applicator (5 animals) or MicroMyst gas-assisted sprayer (5 animals). Sealing of the CSF leak was confirmed by Valsalva maneuver. At 2 months, 2 animals from each group were killed to evaluate dural healing and epidural adhesion formation. The remaining animals were similarly evaluated 4 months after surgery. One animal died at 66 days due to a cause unrelated to hydrogel treatment. In hydrogel-treated animals, all leaking durotomies were sealed intraoperatively. All animals recovered uneventfully. There were no treatment-related health effects. MicroMyst hydrogel application was more controlled, slower, and significantly less thick (p = 0.0094) than Dual Liquid application. All 5 control animals developed subcutaneous CSF accumulations under the incision within days of surgery, compared with only 1 of 10 hydrogel-treated animals (p = 0.002). At 2 and 4 months, control laminectomy sites showed extensive, dense epidural adhesions blending with neodura, compared with hydrogel-treated sites (p < 0.0001 and p = 0.0234, respectively). At 2 months in hydrogel-treated animals, gel filled the epidural space and no epidural adhesions were noted (p < 0.0001 relative to controls). At 4 months, the hydrogel was absorbed. The hydrogel space was filled with scant, loosely organized connective tissue. Hydrogel prevented CSF leakage and mitigated epidural scarring without affecting healing of the dura or laminectomy site. The safety profile of the hydrogel appears favorable due to its synthetic composition, polyethylene glycol chemistry, minimal local tissue response, and lack of neurological deficits. Controlled application of such hydrogel materials may reduce the incidence of postoperative leaks, prevent adhesion formation and thus improve recovery from spinal surgery, and improve identification of tissue planes for reoperations.

Paraplegia complicating selective steroid injections of the lumbar spine. Report of five cases and review of the literature

Selective steroid injections of the lumbar spine carry a risk of paraplegia of sudden onset. Seven cases have been reported in the English literature since 2002. Five new cases have been analyzed, all coming from Paris area centers. Injections were performed between 2003 and 2008. The following items were searched for: location of a previous lumbar spine surgery if any, symptoms indicating the procedure, route of injection, imaging technique used for needle guidance, injection of a contrast medium, type of steroid, other drugs injected if any, paraplegia level, post-procedure MR findings. The current and reported cases were compared. MR findings were consistent with spinal cord ischemia of arterial origin. The high rate of patients who had been operated on in these cases does not correspond to that of patients undergoing injections. The presence of epidural scar might increase the risk. The foraminal route was the only one involved in nonoperated patients. Foraminal, interlaminar, or juxta-zygoapophyseal routes were used in operated-on patients. The high rate of French cases when compared to the literature might arise from the almost exclusive use of prednisolone acetate, a molecule with a high tendency to coalesce in macro-aggregates, putting the spinal cord at risk of arterial supply embolization.

Update on Epidural Scar Prevention and Cerebrospinal Fluid Leaks and Dural Repair

This article seeks to update the practicing spine surgeon on new technologies employed by products recently released (or in development) that facilitate dural repair and grafting, or that seek to prevent epidural fibrosis. An understanding of the attributes and biologic properties that these products utilize will serve to highlight current thinking and techniques. To this end, the surgeon should be able to make critical distinctions about risk/benefit options when selecting products and adopting new techniques.

Management of Adjacent Segment Degeneration and Spinal Stenosis (Scar)

Adjacent segment degeneration after previous lumbar procedures can lead to recurrent symptoms. While many studies have examined the predisposing factors that may contribute to adjacent segment degeneration, few have outlined the management of this condition once it develops. This article reviews the risk factors and diagnostic workup of lumbar adjacent segment degeneration. Operative considerations for the management of spinal stenosis and epidural scar at the junctional level are highlighted. The limited information on surgical outcomes after reoperation is discussed. Emerging technology may offer novel approaches to managing this condition.

DELAYED POSTTRAUMATIC THORACOLUMBAR SPINAL DEFORMITIES

Approximately 50,000 traumatic injuries resulting in fractures of the bony spinal column occur annually in the United States. Although some of these lesions are clearly unstable and mandate urgent surgical treatment for stabilization, less severe injuries may be managed initially with bracing and serial imaging to evaluate bony healing and alignment. A proportion of these injuries will require delayed surgical intervention to correct a posttraumatic deformity. In addition, inadequate or ineffective acute spinal stabilization can also result in the progression of delayed spinal deformities. The management of these lesions is frequently complicated by scarring in the body cavities from the inciting trauma or any subsequent surgical interventions, epidural scar formation and spinal cord tethering, solid fusion into the deformed state, medical comorbidities associated with paralysis, and compromised spinal cord function. With these factors in mind, surgical management of these frequently kyphotic deformities can be performed via a posterior approach with osteotomies or a combined anterior approach and posterior procedures.

Acute Monoplegia After Lysis of Epidural Adhesions: A Case Report

Lysis of epidural adhesions is an interventional procedure performed to treat refractory low back pain or radicular pain due to epidural scarring. A 39-year-old female with a diagnosis of failed back surgery syndrome underwent lysis of epidural adhesions using a Racz catheter. She developed acute monoplegia of her right lower extremity immediately after the procedure. Radiographic imaging did not reveal an epidural hematoma. Motor and sensory function in the right lower limb returned after 5 days. Large volumes of fluid injected during neuroplasty could have caused transient nerve injury from compression within loculated epidural compartments.

Hemilaminoplasty for the treatment of lumbar disc herniation

The aim of this study was to evaluate the clinical outcome of the hemilaminoplasty technique for the treatment of lumbar disc herniation (LDH). Forty-three cases of single-level LDH underwent a discectomy and hemilaminoplasty procedure. The preoperative JOA score and VAS of lower back and leg pain were 10.4+/-1.3, 7.8+/-2.1, and 8.6+/-1.7, respectively. The Cobb angle of lumbar sagittal alignment was 10.1+/-2.0. Twenty-five patients who agreed to lumbar discectomy through fenestration were enrolled as the control group. The postoperative JOA score and VAS of low back and leg pain of the hemilaminoplasty group were 19.4+/-1.3, 1.4+/-0.4, and 2.1+/-0.5, respectively. The Cobb angle was 29.2+/-1.9 degrees. There was no epidural scar observed in any of the patients. The Cobb angle of the hemilaminoplasty group was higher than that of the control group (p < 0.05), while the VAS was significantly lower (p < 0.05). Hemilaminoplasty is a useful method to improve clinical outcome, prevent epidural scar, and preserve the normal alignment of lumbar spine.

Das sog. Postdiskotomiesyndrom - Fehlschläge der Bandscheibenoperation?

The Post-discectomy-Syndrome (PDS) is a clinical entity with various components from individual disposition, sequelae of the underlying disc degeneration and of the operation, as well. These include local back pain, persisting (poly-)radicular pain and facet irritation with pseudoradicular irradiation due to segmental instability, epidural scarring and local arachnoiditis. Diagnosis has to focus on separation from failed-back-surgery-syndromes (FBSS) with single components like insufficient discal or bony decompression or segmental instability. Arachnoiditis seems to be the least modifiable factor and should be excluded if fusion or revision of the spinal canal is planned. A 100 point-score for grading of PDS is presented.

Micro lumbar discectomyの術後瘢痕に関するMRI評価

Micro lumbar discectomyの術後瘢痕に関するMRI評価

The post-diskotomy syndrome

After lumbar disc operations in some cases epidural scars develop. The symptoms consist of back- and leg pain combined with a both sided straight leg raising test. In the myelogram and CT scars can be seen. The conservative therapy can be made by local injections with steroids. A lumbosacral distraction spondylodesis with autologous bone graft can bring a certain relief. Important is a prophylaxis with the right indication for the primary disc operation: without discectomy no post-discectomy-syndrome.

Expulsion postérieure d'un greffon de Biocompatible orthopaedic polymer (BOP) mimant une hernie discale calcifiée lombaire : à propos d'un cas

Objective and importance We present a case of intracanalar extrusion of a L5S1 Biocompatible Orthopaedic Polymer (BOP) graft associated with a L4L5 disc herniation 19 years after a lumbar intersomatic fusion for a L5S1 disc herniation. Radiological aspect of this complication should be recognized by neurosurgeons. Clinical presentation A 55-year old man presented with a right L5 sciatic pain. Neurological examination found a severe weakness in dorsal flexion of the foot. A lumbar CT scanner disclosed aspects consistent with right L4L5 and huge calcified L5S1 lumbar disc herniation. Intervention The patient was operated via a bilateral paravertebral approach and a L5 laminectomy. A dense and extensive epidural scarring was seen. The right L4L5 herniated disc was excised. At the left L5S1 level, fibres from a BOP graft had separated into large fragments extruded into the vertebral canal through the dura. The fibres could only be removed partially because of nerve roots adherence. The patient developed postoperative cerebrospinal fluid (CSF) leakage that required a second operation for dural closure. The postoperative course was uneventful and the patient recovered the right L5 root deficit. Conclusion Neurosurgeons should be aware of the radiological aspect of this complication. If it is recognized on CT scan and asymptomatic, conservative management should be proposed because of the risk of nerve roots injury or postoperative CSF leakage.

Surgical Interventions for Lumbar Disc Prolapse

An updated Cochrane Review. To assess the effects of surgical interventions for the treatment of lumbar disc prolapse. Disc prolapse accounts for 5% of low back disorders yet is one of the most common reasons for surgery. There is still little scientific evidence supporting some interventions. Use of standard Cochrane review methods to analyze all randomized controlled trials published up to January 1, 2007. Forty randomized controlled trials (RCTs) and 2 quasi-RCTs were identified. Many of the early trials were of some form of chemonucleolysis, whereas the majority of the later studies either compared different techniques of discectomy or the use of some form of membrane to reduce epidural scarring. Four trials directly compared discectomy with conservative management, and these give suggestive rather than conclusive results. However, other trials show that discectomy produces better clinical outcomes than chemonucleolysis, and that in turn is better than placebo. Microdiscectomy gives broadly comparable results to standard discectomy. Recent trials of an interposition gel covering the dura (5 trials) and of fat (4 trials) show that they can reduce scar formation, although there is limited evidence about the effect on clinical outcomes. There is insufficient evidence on other percutaneous discectomy techniques to draw firm conclusions. Three small RCTs of laser discectomy do not provide conclusive evidence on its efficacy. There are no published RCTs of coblation therapy or transforaminal endoscopic discectomy. Surgical discectomy for carefully selected patients with sciatica due to lumbar disc prolapse provides faster relief from the acute attack than conservative management, although any positive or negative effects on the lifetime natural history of the underlying disc disease are still unclear. The evidence for other minimally invasive techniques remains unclear except for chemonucleolysis using chymopapain, which is no longer widely available.

Use of newly developed instruments and endoscopes: full-endoscopic resection of lumbar disc herniations via the interlaminar and lateral transforaminal approach

Even with good results, conventional disc operations may result in subsequent damage due to trauma. Endoscopic techniques have become the standard in many areas because of the advantages they offer intraoperatively and postoperatively in rehabilitation. The goal of this prospective study was to examine the expanded technical possibilities of full-endoscopic transforaminal and interlaminar resection of herniated lumbar discs in which the authors used newly developed optics and instruments. The focus was on questions of achieving sufficient decompression, as well as the advantages and disadvantages of the minimally invasive procedure. Two hundred thirty-two patients underwent follow up for 2 years after undergoing surgery. In addition to general and specific parameters, the following measuring instruments were used: a visual analog scale, the German version of the North American Spine Society instrument, and the Oswestry Disability Index of low-back pain disability. Postoperatively 84% of the patients no longer had leg pain, and 12% had only occasional pain. The results of decompression were equivalent to those of conventional procedures. The incidence of traumatization was reduced. Epidural scarring was minimized. The recurrence rate was 6.0%. No serious surgical complications were observed. Resection of the herniated disc was technically possible in all cases in which the new instruments were used. The authors view the aforedescribed techniques, which offer the advantages of a truly minimally invasive procedure, as a sufficient and safe supplementation and alternative to conventional procedures, when the appropriate indication criteria are heeded. The new endoscope with its 4.2-mm working channel and corresponding instruments significantly reduced the technical problems.