Fibrous adhesive entrapment of lumbosacral nerve roots as a cause of sciatica

My Double Trouble: An Autobiographical Case Report of Psoriasis and Psoriatic Arthritis

Psoriasis and psoriatic arthritis are overlapping, related, but distinct entities. Each occurs as a result of a complex combination of precipitants, genetic predispositions, and variable expression of a self-sustaining proinflammatory state. My case history and clinical course are outlined below. In addition, the epidemiology, pathogenesis, and the expanding armamentarium of treatment options, including their strengths and weaknesses, are discussed in detail.   

[Entrapment neuropathies: a contemporary approach to pathophysiology, clinical assessment, and management : German version]

Entrapment neuropathies such as carpal tunnel syndrome, radiculopathies, or radicular pain are the most common peripheral neuropathies and also the most common cause for neuropathic pain. Despite their high prevalence, they often remain challenging to diagnose and manage in a clinical setting. Summarising the evidence from both preclinical and clinical studies, this review provides an update on the aetiology and pathophysiology of entrapment neuropathies. Potenzial mechanisms are put in perspective with clinical findings. The contemporary assessment is discussed and diagnostic pitfalls highlighted. The evidence for the noninvasive and surgical management of common entrapment neuropathies is summarised and future areas of research are identified.

MICAL2 regulates myofibroblasts differentiation in epidural fibrosis via SRF/MRTF-A signaling pathway

AIM

To determine the role of MICAL2 in myofibroblasts differentiation and epidural fibrosis.

BACKGROUND

Epidural fibrosis (EF) may develop following laminectomy and aberrant myofibroblasts differentiation and excessive extracellular matrix (ECM) accumulation play key roles in the formation of EF. Dense epidural fibrosis results to the poor surgical outcomes and failed back surgery syndrome (FBSS), and there is no effective treatment available. Molecule interacting with Casl2 (MICAL2) has been demonstrated to participate in multiple cellular processes by regulating actin cytoskeleton dynamics. However, its role in epidural fibrosis remains totally unverified.

MATERIALS AND METHODS

The potential functions and mechanisms of MICAL2 were explored using western blotting, immunofluorescence and lentivirus infection.

KEY FINDINGS

In our study, we determined that the MICAL2 expression was elevated in epidural fibrotic tissues and TGF-β1-stimulated fibroblasts. Moreover, knockdown of MICAL2 using MICAL2-specific short hairpin RNA attenuated TGF-β1-induced myofibroblasts differentiation and epidural fibrosis both in vitro and vivo, as indicated by decreased scar formation, reduced collagen production and down-regulated expression of α-SMA, collagen-1 and fibronectin. We also demonstrated that MICAL2 knockdown affected the migratory capability of fibroblasts in vitro. By further mechanistic research, we revealed that the MRTF-A nuclear translocation was inhibited in response to the knockdown of MICAL2 in fibroblasts and MICAL2 served as a pro-fibrotic factor in an SRF/MRTF-A-dependent manner.

SIGNIFICANCE

In conclusion, our results indicated that MICAL2 mediated myofibroblasts differentiation and promoted epidural fibrogenesis via SRF/MRTF-A signaling pathway, suggesting manipulation of MICAL2 activity as a novel alternative strategy for the prevention of epidural fibrosis.

Entrapment neuropathies: a contemporary approach to pathophysiology, clinical assessment, and management

Entrapment neuropathies such as carpal tunnel syndrome, radiculopathies, or radicular pain are the most common peripheral neuropathies and also the most common cause for neuropathic pain. Despite their high prevalence, they often remain challenging to diagnose and manage in a clinical setting. Summarising the evidence from both preclinical and clinical studies, this review provides an update on the aetiology and pathophysiology of entrapment neuropathies. Potential mechanisms are put in perspective with clinical findings. The contemporary assessment is discussed and diagnostic pitfalls highlighted. The evidence for the noninvasive and surgical management of common entrapment neuropathies is summarised and future areas of research are identified.

A novel bacterial cellulose membrane immobilized with human umbilical cord mesenchymal stem cells-derived exosome prevents epidural fibrosis

Introduction

Failed back surgery syndrome is a situation where there is failure after lumbar surgery aimed at correcting lumbar disease that is characterized by continuous back and/or leg pain. Epidural fibrosis and adhesions are among the major causes of failed back surgery syndrome. In recent years, several biomaterials have been applied as barriers or deterrents to prevent the compression of neural structures by postsurgical fibrosis.

Methods

In this study, a new bacterial cellulose (BC) anti-adhesion membrane, composed of exosomes from human umbilical cord mesenchymal stem cells, was developed. Its structure and morphology, water content, thickness, and mechanical properties of elasticity were analyzed and characterized. The degradation of the BC+exosomes (BC+Exos) membrane in vitro was evaluated, and its in vitro cytotoxicity and in vivo biocompatibility were tested. The prevention effect of BC+Exos membrane on epidural fibrosis post-laminectomy in a rabbit model was investigated.

Results

The BC+Exos membrane showed a three-dimensional network structure constituted of high-purity cellulose and moderate mechanical properties. No degeneration was observed. The BC+Exos membrane showed no cytotoxicity and displayed biocompatibility in vivo. The BC+Exos film was able to inhibit epidural fibrosis and peridural adhesions.

Conclusion

Based on the current findings, the BC+Exos membrane is a promising material to prevent postoperative epidural fibrosis and adhesion.

Effectiveness and Safety of Acupotomy for Lumbar Disc Herniation: A Randomized, Assessor-Blinded, Controlled Pilot Study

Objective

Patients with lumbar disc herniation (LDH) suffer from pain, physical disabilities, and low quality of life. This study was designed to evaluate the effectiveness and safety of acupotomy in patients with LDH.

Method

Fifty participants with LDH were recruited to this randomized, assessor-blinded, controlled study and randomly assigned to the acupotomy (n = 25) or manual acupuncture (n = 25) group. The acupotomy group received acupotomy four times in 2 weeks, while the manual acupuncture group received manual acupuncture six times in 2 weeks. The follow-up visit was planned in the 4th week (i.e., 2 weeks after the final intervention). The primary outcome was the change in the Visual Analogue Scale (VAS) at follow-up. The changes in the Oswestry Disability Index (ODI), Modified-Modified Schober Test (MMST), and EuroQol Five Dimensions (EQ-5D) questionnaire were also evaluated. An intention-to-treat analysis was applied and adverse events were recorded.

Results

The acupotomy group showed significant changes in VAS, ODI, and EQ-5D after intervention. VAS and ODI in the 4th week were lower in the acupotomy than in the manual acupuncture group. The acupotomy group showed consistent changes in VAS and ODI in the 1st, 2nd, and 4th week. No serious adverse event was reported in the acupotomy group.

Conclusion

This study suggests greater therapeutic effects of acupotomy on relieving pain and improving the functional disability associated with LDH than those observed with manual acupuncture.

Controllable Risk Factors for Neurologic Complications in Posterior Lumbar Interbody Fusion as Revision Surgery

BACKGROUND

The main concern with revision lumbar surgery is the possibility of neurologic complications. This retrospective study was conducted to clarify the risk factors, especially the effects of nerve stretching, for postoperative neurologic complications in posterior lumbar interbody fusion (PLIF) without excessive nerve retraction by bilateral total facetectomy as revision surgery.

METHODS

Between 2005 and 2015, 50 consecutive patients underwent revision PLIF for recurrent stenosis or recurrent disc herniation. The patients were divided into two groups: patients with neurological complications (NC group) and patients without neurological complications (non-NC group). Radiological examinations to evaluate the magnitude of nerve stretching included the following pre- and postoperative plain radiograph measurements: anterolisthesis at flexion, intervertebral lordosis in the neutral position, and posterior disc height in the neutral position.

RESULTS

Sixteen patients (32%) had neurological complications. The decrease in intervertebral lordosis was significantly greater in the NC group than that in the non-NC group (0.8° vs. -1.5°, P<0.05). Distraction of the posterior disc height was significantly greater in the NC group than that in the non-NC group (5.0 mm vs. 2.6 mm, P < 0.01). Neurological complications were seen in all patients with a decrease in intervertebral lordosis >3° and distraction of the posterior disc height >3 mm.

CONCLUSIONS

Decreased intervertebral lordosis, and distraction of the posterior disc height, which can be controlled by surgeons, appear to be risk factors for neurological complications following revision PLIF. In revision PLIF, surgeons should create segmental lordosis without excessive disc height distraction.

Epidurographic Findings Following Percutaneous Epidural Adhesiolysis Failed to Correlate with Level of Pain Reduction in Patients with Lumbar Spinal Stenosis

Background

Spinal stenosis is characterized by narrowing of the spinal canal, with mechanical compression of spinal nerve roots. The latter may cause low back pain and/or leg pain, as well as neurogenic claudication. Epidural steroid injection is commonly used to treat patients with lumbar spinal stenosis (LSS), but percutaneous epidural adhesiolysis has been utilized when symptoms prove refractory. Our goal was to assess the relationship between improvement shown on epidurogram and subjective patient response to adhesiolysis.

Methods

For this prospective study, 78 patients with degenerative LSS were enrolled. Each subject underwent magnetic resonance imaging of the lumbar spine, with all therapeutic procedures conducted in the operating room. Two weeks later, a second epidurography was performed. Second epidurography was conducted to assess any change in epidural filling defects. Outcome measures were obtained using the visual analogue scale (VAS) score at two weeks, one month, and three months post-treatment.

Results

All of the 78 study participants (mean age = 60.9 years, range = 34-85 years) displayed epidural filling defects at baseline. After percutaneous adhesiolysis, epidurographic filling defects were absent in 73% of patients. In the presence or absence of filling defects, mean VAS scores were 5.2 and 4.5, respectively, at two weeks' follow-up. No significant correlation between postprocedural VAS score and status of filling defects (yes or no) was evident during the three-month follow-up period.

Conclusion

In patients with LSS, epidurographic findings following percutaneous epidural adhesiolysis failed to correlate with level of pain reduction achieved.

Reduction of Leg Pain by Oxiplex Gel After Lumbar Discectomy in Patients With Predominant Leg Pain and Elevated Levels of Lower Back Pain: A Prospective, Randomized, Blinded, Multicenter Clinical Study

STUDY DESIGN

A prospective, randomized, blinded, multicenter clinical study.

OBJECTIVE

To evaluate carboxymethylcellulose/polyethylene oxide gel (Oxiplex) in improving clinical outcomes in subjects having predominant leg pain and elevated low back pain undergoing first-time lumbar discectomy for disk herniation.

SUMMARY OF BACKGROUND DATA

Clinical studies in the United States and Italy found that Oxiplex reduced leg pain after decompression surgery.

METHODS

A total of 68 subjects with herniated lumbar disk were enrolled and randomized into treatment (surgery plus gel) or surgery-only control groups. A prospective statistical analysis assessed the effect of gel in the severe back pain subgroup (prespecified as greater than or equal to median baseline back pain of the population studied). All subjects except 2 controls lost to follow-up completed the study. Preoperative and postoperative visual analogue scale leg pain scores were analyzed and compared between groups at 60 days after surgery.

RESULTS

There were no serious adverse events or neurological safety concerns reported in any patients. Gel-treated patients had statistically significantly lower visual analogue scale leg pain scores at study end compared with controls (P=0.0240), representing a 21% additional reduction in leg pain compared with surgery alone in the severe baseline back pain subgroup (P=0.0240). The proportion of subgroup patients experiencing zero leg pain at study end was significantly higher in the gel treatment group (60%) than in the control group (23%) (P=0.0411).

CONCLUSIONS

The data from this study confirm and extend results of 2 previous studies in Italy and the United States that reported statistically significantly greater reductions in leg pain in gel-treated patients with severe preoperative low back pain compared with patients who only underwent decompression surgery.

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.

The use of a dehydrated amnion/chorion membrane allograft in patients who subsequently undergo reexploration after posterior lumbar instrumentation

Background Context. Products that can reduce development of epidural fibrosis may reduce risk for ongoing pain associated with development of scar tissue and make subsequent epidural reexploration easier. Purpose. To evaluate the use of dehydrated human amnion/chorion membrane (dHACM) on the formation of soft tissue scarring in the epidural space. Study Design. Case series. Patient Sample. Five patients having transforaminal lumbar interbody lumbar fusion (TLIF) with posterior instrumentation and implantation of dHACM in the epidural space and subsequent epidural reexploration. Outcome Measures. Degree of scar tissue adjacent to the epidural space at reexploration. Intraoperative and postoperative complications related to dHACM and patient reported outcomes. Methods. The degree of scar tissue adjacent to the epidural space was assessed during the reexploration surgery. Patients' outcomes were collected using standard validated questionnaires. Results. Four of 5 cases had easily detachable tissue during epidural reexploration. Angiolipoma of 10% was noted in 1 case and 5% in 2 cases. Significant improvements in patient reported outcomes were observed. No intraoperative or postoperative complications occurred. Conclusions. Our findings suggest that dHACM implant during TLIF may have favorable effects on epidural fibrosis and is well tolerated. Further studies with larger cohorts are required to prove our results.

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.

Oxiplex reduces leg pain, back pain, and associated symptoms after lumbar discectomy

STUDY DESIGN

Prospective, randomized, blinded clinical trial.

OBJECTIVE

To evaluate effectiveness of Oxiplex gel for reduction of pain and associated symptoms after lumbar discectomy.

SUMMARY OF BACKGROUND DATA

Oxiplex gel (carboxymethylcellulose, polyethylene oxide, and calcium) is used during discectomy to coat the surgical site for reduction of pain and symptoms after lumbar discectomy.

METHODS

Patients undergoing single-level lumbar discectomy performed by laminectomy or laminotomy and randomized to receive either surgery plus Oxiplex gel (treatment group) or surgery alone (control group) were assessed 6 months after surgery using (1) a quality of life questionnaire (Lumbar Spine Outcomes Questionnaire [LSOQ]) and (2) clinical evaluations.

RESULTS

There were no statistically significant differences in baseline demographics, surgical procedures, LSOQ scores, and clinical evaluations between treatment (N = 177) and control (N = 175) groups. More gel-treated patients were satisfied with outcome of their surgical treatment than control patients (P = 0.05). The gel-treated group showed greater reductions in pain and symptoms from baseline compared with surgery-only controls. Additional benefits of gel were consistently shown in reduction of leg and back pain at 6 months in the patient population having substantial back pain at baseline (greater than or equal to the median LSOQ pain score of 63). In that population, there was a statistically significant reduction of leg pain and back pain (P < 0.01) in the treatment group compared with controls. Fewer patients in the treatment group had abnormal musculoskeletal physical examinations at 6 months compared with controls. There were no cases of cerebrospinal fluid leaks and no differences in laboratory values or vital signs. Patients in the treatment group had less hypoesthesia, paraesthesia, sensory loss, and fewer reoperations during the 6-month follow-up than controls (1 vs. 6).

CONCLUSION

These data demonstrate improvements in clinical outcomes resulting from the use of Oxiplex gel in discectomy procedures for treatment of lumbar disc herniation.

Use of Temporary Implantable Biomaterials to Reduce Leg Pain and Back Pain in Patients with Sciatica and Lumbar Disc Herniation

The principle etiology of leg pain (sciatica) from lumbar disc herniation is mechanical compression of the nerve root. Sciatica is reduced by decompression of the herniated disc, i.e., removing mechanical compression of the nerve root. Decompression surgery typically reduces sciatica more than lumbar back pain (LBP). Decompression surgery reduces mechanical compression of the nerve root. However, decompression surgery does not directly reduce sensitization of the sensory nerves in the epidural space and disc. In addition, sensory nerves in the annulus fibrosus and epidural space are not protected from topical interaction with pain mediators induced by decompression surgery. The secondary etiology of sciatica from lumbar disc herniation is sensitization of the nerve root. Sensitization of the nerve root results from a) mechanical compression, b) exposure to cellular pain mediators, and/or c) exposure to biochemical pain mediators. Although decompression surgery reduces nerve root compression, sensory nerve sensitization often persists. These observations are consistent with continued exposure of tissue in the epidural space, including the nerve root, to increased cellular and biochemical pain mediators following surgery. A potential contributor to lumbar back pain (LBP) is stimulation of sensory nerves in the annulus fibrosus by a) cellular pain mediators and/or b) biochemical pain mediators that accompany annular tears or disruption. Sensory fibers located in the outer one-third of the annulus fibrosus increase in number and depth as a result of disc herniation. The nucleus pulposus is comprised of material that can produce an autoimmune stimulation of the sensory nerves located in the annulus and epidural space leading to LBP. The sensory nerves of the annulus fibrosus and epidural space may be sensitized by topical exposure to cellular and biochemical pain mediators induced by lumbar surgery. Annulotomy or annular rupture allows the nucleus pulposus topical access to sensory nerve fibers, thereby leading to LBP. Coverage of the annulus and adjacent structures in the epidural space by absorbable viscoelastic gels appears to reduce LBP following surgery by protecting sensory fibers from cellular and biochemical pain mediators.

The role of computed tomography in the presurgical diagnosis of foraminal entrapment of lumbosacral junction

OBJECTIVE

On the basis of preoperative computed tomography (CT) scans, we studied the change of the size of anterior primary division (APD) of the L5 spinal root in the presence of foraminal/extraforaminal entrapment of the L5 spinal root.

METHODS

Two independent radiologists retrospectively reviewed the preoperative CT scans of 27 patients treated surgically and compared the sizes of the APDs on bilateral L5 spinal roots. If one side APD size was larger than the other side APD size, it was described as left or right "dominancy" and regarded this as "consensus (C)" in case that there was a consensus between the larger APD and the location of sciatica, and regarded as "non-consensus (NC)" in case that there was not a consensus. Oswestry Disability Index (ODI) scores were used for preoperative and postoperative evaluation.

RESULTS

On CT scans, twenty-one (77%) of 27 patients were the consensus group (APD swelling) and 6 (22%) were a non-consensus group (APD no swelling). In 9 patients with acute foraminal disc herniations, asymmetric enlargement of the APD on L5 spinal root was detected in all cases (100%) and detected in 11 (64%) of 17 patients with stenosis. Preoperative ODI score was 75-93 (mean 83) and postoperative ODI scores were improved to 13-36 (mean 21). The mean follow-up period was 6 months (range, 3-11 months).

CONCLUSION

An asymmetric enlargement of the APD on L5 spinal root on CT scans is meaningfully associated with a foraminal or extraforaminal entrapment of the L5 spinal root on the lumbosacral junction.

PATHOANATOMIC BASIS FOR STRETCH-INDUCED LUMBAR NERVE ROOT INJURY WITH A REVIEW OF THE LITERATURE

OBJECTIVE

Persistent pain originating from a dysfunctional lumbar motion segment poses significant challenges in the clinical arena. Although the predominance of the existing spine literature has addressed nerve root compression as the principal cause of pain, it is equally likely that a stretch mechanism may be responsible for all or part of the pathology.

METHODS

The literature supporting the role of stretch damage as a primary cause of nerve root injury and pain was systematically reviewed. Pathoanatomic considerations between nerve roots and juxtaposed environment are described and correlated with the available literature. Potential anatomic relationships that may lead to stretch-induced injury are delineated.

RESULTS

A dynamic lumbar functional spinal unit that encloses a tethered nerve root can create significant stretch and/or compression. This phenomenon may be present in a variety of pathological conditions. These include anterior, posterior, and rotatory olisthesis as well as degenerative conditions such as the loss of disc interspace height and frank multisegment spinal deformity. Although numerous studies have demonstrated that stretch can result in nerve damage, the pathophysiology that may associate nerve stretch with chronic pain has yet to be determined.

CONCLUSION

The current literature concerning stretch-related injury to nerve roots is reviewed, and a conceptual framework for its diagnosis and treatment is proposed and graphically illustrated using cadaveric specimens. The dynamic biomechanical and functional interrelationships between neural structures and adjacent connective tissue elements are particularly important in the face of spinal deformity.

A modern biomaterial for adhesion prevention

A biomaterial composed of carboxymethylcellulose, poly(ethylene oxide), and calcium can be prepared in a variety of ways to reduce fibrin deposition and adhesion formation. This biomaterial platform can be formulated into a flowable gel with tissue adherence appropriate for use in minimally invasive surgery. The device remains at the site of placement even in gravitationally dependent areas. A peridural formulation was shown in preclinical studies to be safe and effective in reducing adhesions to dura following spinal surgery. A peritoneal formulation used on pelvic organs following peritoneal cavity surgery was also shown to be safe and effective. A clinical feasibility study showed that patients with severe back pain and lower extremity weakness treated with the peridural formulation, applied over their nerve roots following laminectomy or laminotomy, experienced significantly reduced symptoms when compared with surgery-only controls. The peritoneal formulation was shown in two multicenter feasibility studies of women undergoing pelvic surgery to significantly reduce adhesion formation when compared with surgery-only controls. Confirmation of the feasibility studies awaits results from pivotal clinical trials. These formulations were safe, effective, and easy to use. This biomaterial provided a benefit to patients undergoing surgery where postsurgical adhesion formation is a concern.

Reduction in leg pain and lower-extremity weakness with Oxiplex/SP Gel for 1 year after laminectomy, laminotomy, and discectomy

Object

Although good surgical technique is effective in reducing postoperative epidural fibrosis, compression or tethering of the nerve root may cause recurrent radicular pain and physical impairment. The implantation of a bioresorbable gel on the dura may further decrease the amount of scar formation after surgery and thus improve the patient's ability to perform activities of daily living (ADL). This study is a 12-month evaluation of the safety and effectiveness of Oxiplex/SP Gel (FzioMed, Inc., San Luis Obispo, CA) in the reduction of pain and radiculopathy after lumbar discectomy.

Methods

A pilot randomized single-blind multicenter clinical trial was conducted to evaluate the performance of Oxiplex/SP Gel in patients who underwent surgery for unilateral herniation of the lumbar disc at L4–5 or L5–S1. Eighteen patients with severe leg pain and lower-extremity weakness (11 women and seven men) were randomly assigned intraoperatively to receive the gel at the conclusion of surgery (treatment group) or to undergo surgery alone (control group). Self-assessment questionnaires (Lumbar Spine Outcomes Questionnaire) to assess pain, symptoms, and ADL were completed preoperatively and at scheduled postoperative intervals (30 days, 90 days, 6 months, and 12 months).

The authors examined the spine and lower extremities of patients scheduled for discectomy to assess neurological function and pain. Treated patients received sufficient Oxiplex/SP Gel (1–3 ml) to coat the nerve root and fill the epidural space. Postoperative clinical evaluations were performed at 30 and 90 days. Patients completed the self-assessment questionnaires at baseline and were contacted by telephone or mail for the completion of the postoperative self-assessment questionnaires.

Surgical procedures were well tolerated; no device-related adverse events and no clinically significant laboratory results were reported. The 11 patients with severe leg pain and lower-extremity weakness who were treated with Oxiplex/SP Gel had a reduction in those symptoms at 30 days, 90 days, 6 months, and 12 months after discectomy, compared with the seven control patients who underwent surgery only.

Conclusions

Oxiplex/SP Gel was easy to use and safe in patients who underwent unilateral discectomy. A greater benefit in clinical outcome measures was seen over the 12-month follow-up period in gel-treated patients.

Three-dimensional analysis of the movement of lumbar spinal nerve roots in nonsimulated and simulated adhesive conditions

STUDY DESIGN

Biomechanical analysis of the movement of the lumbar spinal nerve roots (NRs).

OBJECTIVES

The characteristics of the movement of lumbar spinal NRs corresponding to the change of posture were three-dimensionally analyzed in nonsimulated and simulated adhesion conditions using a porcine model.

SUMMARY OF BACKGROUND DATA

There is a paucity of data on the movement of NRs.

MATERIALS AND METHODS

Thirty two NRs of four pig cadavers were investigated. (study 1) Two tantalum beads were sutured on respective NRs from L3 to L6. Five beads were put into each bony structure as reference points. The porcine body was put on the cage designed for three-dimensional radiostereometric analysis. Two oblique radiographs were simultaneously taken at flexion, neutral, and extension. (study 2) After study 1, either L4 NR was ligated onto the adjacent bone to mimic monoradicular adhesion. Radiographs were taken in the same manner. The movements of the beads on NRs relative to immobile standard points in each vertebra were analyzed.

RESULTS

The movement of NRs was characterized as a combination of stretching/slackening and pendulum motion. The distance that NRs were stretched/slackened, the excursion, and the angles that NRs moved were: 0.39 +/- 0.29 mm, 1.81 +/- 0.63 mm, and 10.46 +/- 5.93 degrees (in nonadhesion), and 0.30 +/- 0.20 mm, 1.02 +/- 0.50 mm, and 7.13 +/- 3.79 degrees (in simulated adhesion), respectively.

CONCLUSION

Adhesion might play a part in the pathogenesis of lumbar spinal disorders because mechanical irritation secondary to stretching/slackening and pendulum motion might be concentrated at the distal part of NRs, adjacent to adhesion site, which has less cerebrospinal fluid and is close to dorsal root ganglion.

Reduction of radiculopathy and pain with Oxiplex/SP gel after laminectomy, laminotomy, and discectomy: a pilot clinical study

STUDY DESIGN

Safety using Oxiplex/SP Gel during single-level discectomy for reduction of symptoms associated with unilateral herniation of the lumbar disc was investigated by self-assessment questionnaire and magnetic resonance imaging.

OBJECTIVE

To evaluate the safety and assess the efficacy parameters of Oxiplex/SP Gel.

SUMMARY OF BACKGROUND DATA

Animal studies demonstrated that Oxiplex/SP Gel (CMC/PEO) reduced epidural fibrosis after lumbar surgery.

METHODS

Surgeons examined spine and lower extremities of patients scheduled for discectomy to assess neurologic function and pain. Treated patients received sufficient Oxiplex/SP Gel (1-3 mL) to coat the nerve root and fill the epidural space. The control condition was surgery alone. At baseline, then 30 days, 90 days, and 6 months after surgery, patients completed self-assessment questionnaires concerning leg pain, lower extremity weakness, functional disability, daily living activities, symptoms, and radiculopathy. Magnetic resonance imaging was performed at baseline and 90 days after surgery. At 30 and 90 days after surgery, patients underwent physical examination, wound inspection, and laboratory tests.

RESULTS

The surgical procedures were well tolerated by the 23 patients treated with Oxiplex/SP Gel and the 11 control patients. There were no unanticipated adverse events, no clinically significant laboratory results, and no significant differences detected by magnetic resonance imaging. Treated patients had greater reduction in outcome measures at 30 days. The differences in scores were attenuated at 90 days and 6 months. A subgroup, the patients with significant leg pain and weakness at baseline (11 patients treated with Oxiplex/SP Gel and 7 control patients), had greater reduction in outcome measures than the control patients throughout the study.

CONCLUSIONS

Oxiplex/SP Gel was easy to use and safe for patients undergoing unilateral discectomy. Greater benefit in clinical outcome measures was seen in gel-treated patients, especially those with severe leg pain and weakness at baseline.