Nerve root block versus surgery (NERVES) for the treatment of radicular pain secondary to a prolapsed intervertebral disc herniation: study protocol for a multi-centre randomised controlled trial.

BACKGROUND: Sciatica is a common condition reported to affect over 3% of the UK population at any time and is often caused by a prolapsed intervertebral disc (PID). Although the duration and severity of symptoms can vary, pain persisting beyond 6 weeks is unlikely to recover spontaneously and may require investigation and treatment. Currently, there is no specific care pathway for sciatica in the National Health Service (NHS), and no direct comparison exists between surgical microdiscectomy and transforaminal epidural steroid injection (TFESI). The NERVES (NErve Root block VErsus Surgery) trial aims to address this by comparing clinical and cost-effectiveness of surgical microdiscectomy and TFESI to treat sciatica secondary to a PID. METHODS/DESIGN: A total of 163 patients were recruited from NHS out-patient clinics across the UK and randomised to either microdiscectomy or TFESI. Adult patients (aged 16-65 years) with sciatic pain endured for between 6 weeks and 12 months are eligible if their symptoms have not been improved by at least one form of conservative (non-operative) treatment and they are willing to provide consent. Patients will be excluded if they present with neurological deficit or have had previous surgery at the same level. The primary outcome is patient-reported disability measured using the Oswestry Disability Questionnaire (ODQ) score at 18 weeks post randomisation and secondary outcomes include disability and pain scales using numerical pain ratings, modified Roland-Morris and Core Outcome Measures Index at 12-weekly intervals, and patient satisfaction at 54 weeks. Cost-effectiveness and quality of life (QOL) will be assessed using the EQ-5D-5 L and self-report cost data at 12-weekly intervals and Hospital Episode Statistics (HES) data. Adverse event data will be collected. Analysis will follow the principle of intention-to-treat. DISCUSSION: NERVES is the first trial to evaluate the comparative clinical and cost-effectiveness of microdiscectomy to local anaesthetic and steroid administered via TFESI. The results of this research may facilitate the development of an evidence-based treatment strategy for patients with sciatica. TRIAL REGISTRATION: ISRCTN, ID: ISRCTN04820368 . Registered on 5 June 2014. EudraCT EudraCT2014-002751-25. Registered on 8 October 2014.

Patients with low back pain differ from those who also have leg pain or signs of nerve root involvement - a cross-sectional study.

BACKGROUND: Leg pain associated with low back pain (LBP) is recognized as a risk factor for a poor prognosis, and is included as a component in most LBP classification systems. The location of leg pain relative to the knee and the presence of a positive straight leg raise test have been suggested to have clinical implications. To understand differences between such leg pain subgroups, and whether differences include potentially modifiable characteristics, the purpose of this paper was to describe characteristics of patients classified into the Quebec Task Force (QTF) subgroups of: 1) LBP only, 2) LBP and pain above the knee, 3) LBP and pain below the knee, and 4) LBP and signs of nerve root involvement. METHODS: Analysis of routine clinical data from an outpatient department. Based on patient reported data and clinical findings, patients were allocated to the QTF subgroups and described according to the domains of pain, activity limitation, work participation, psychology, general health and clinical examination findings. RESULTS: A total of 2,673 patients aged 18-95 years (median 47) who were referred for assessment of LBP were included. Increasing severity was consistently observed across the subgroups from LBP only to LBP with signs of nerve root involvement although subgroup differences were small. LBP patients with leg pain differed from those with LBP only on a wide variety of parameters, and patients with signs of nerve root involvement had a more severe profile on almost all measures compared with other patients with back-related leg pain. CONCLUSION: LBP patients with pain referral to the legs were more severely affected than those with local LBP, and patients with signs of nerve root involvement were the ones most severily affected. These findings underpin the concurrent validity of the Quebec Task Force Classification. However, the small size of many between-subgroup differences amid the large variability in this sample of cross-sectional data also underlines that the heterogeneity of patients with LBP is more complex than that which can be explained by leg pain patterns alone. The implications of the observed differences also require investigation in longitudinal studies.

Development of an assessment schedule for patients with low back-associated leg pain in primary care: a Delphi consensus study.

PURPOSE: The objectives of this study were to develop consensus on (i) the content of a clinical assessment for adults presenting to primary care with low back and leg pain, and (ii) the most important items for diagnosing spinal nerve root involvement. METHODS: Existing literature and expert knowledge was used to compile a list of items pertaining to clinical history questions and examination tests employed in the assessment of patients with low back pain with suspected spinal nerve involvement. A Delphi consensus method was employed to rate the importance of items for clinical assessment and for diagnosis in two web-based rounds. A multidisciplinary group of 42, including GPs, physiotherapists, osteopaths, rheumatologists, spinal orthopaedic surgeons and chiropractors took part. Items were included in the final assessment when over 70% of participants rated them as important. RESULTS: Thirty-four items were included in the clinical assessment, and 15 items for diagnosis. History items included pain distribution in the leg, pain quality and behaviour, altered sensation, functional limitations and yellow flags, previous history of similar symptoms and outcome of previous treatment/management. Examination items included typical neurological tests including neural tension and 'demonstration of movement that produces symptoms'. CONCLUSIONS: We have developed a clinical assessment schedule for patients with low back pain and leg pain presenting in primary care. History and clinical items considered important for their contribution in the diagnosis of nerve root involvement were also established.

Assessment of pure single nerve root resection in the treatment of spinal schwannoma: focus on solitary spinal schwannomas located below the thoracolumbar junction.

BACKGROUND: The incidence of neurological deficits is reportedly low after sacrificing the affected nerve root during spinal schwannoma treatment. Although the incidence has been widely reported, the operative method for nerve root resection has been not clarified. To evaluate the safety of pure nerve root resection, we focused on solitary spinal schwannomas below the thoracolumbar level and investigated the effect of affected nerve resection. METHODS: Twenty-three spinal schwannoma patients were retrospectively examined. The mean age at surgery was 53 years. We investigated preoperative symptoms, duration of the disorder, postoperative neurological deficits, and clinical outcomes. In addition, we measured tumor size on computed tomography after myelography or on magnetic resonance images using image-analysis software. We retrospectively assessed correlations among duration of symptoms, tumor size, and postoperative neurological deficits. RESULTS: The tumors comprised 19 intradural schwannomas and 4 dumbbell-shaped schwannomas. No postoperative neurological deficits were observed in the intradural schwannoma patients. In contrast, three of the four dumbbell-shaped schwannoma patients experienced postoperative neurological deficits. Among these three patients, two recovered quickly whereas one never recovered. The mean duration of the disorder was 29 months. The postoperative modified JOA score (13.0) was significantly improved compared with the preoperative score (8.9). The mean maximum tumor sizes were 97.2 mm(2) for the intradural schwannomas and 884.0 mm(2) for the dumbbell-shaped schwannomas. There were no correlations among tumor size, duration of the disorder, and postoperative neurological deficits. CONCLUSIONS: On the basis of this study, we recommend pure single nerve resection for treatment of intradural spinal schwannomas before such tumors progress and involve other normal roots, because postoperative neurological deficits did not occur in our intradural schwannoma patients, irrespective of tumor size, when this procedure was used. However, dumbbell-shaped schwannoma patients should be carefully treated operatively, because high incidence of postoperative neurological deficits can be expected.

A comparison of a commercially made pedicle stimulating probe with a custom-made device: does the commercial device detect pedicle wall breaches more reliably?

STUDY DESIGN: Clinical trial. OBJECTIVE: To compare the efficacy of a commercially available stimulating pedicle probe with a custom-made probe for the detection of pedicle wall breaches during screw insertion for the surgical correction of scoliosis. SUMMARY OF BACKGROUND DATA: Stimulus triggered electromyography has been used to detect small breaches in the walls of the spinal pedicles during pedicle screw insertion. We routinely use a reusable, custom-made clip that can be attached to the screw, pedicle probe, or other instruments. Commercial systems are available in which the instrument is electrically instrumented to deliver current. METHODS: In five patients (173 pairs of tests), we compared the threshold current required to trigger an electromyographic response during testing of the pedicle. Each track or screw was tested with both the custom-made and the commercial probe and the threshold current recorded. RESULTS: Both systems were able to detect pedicle wall breaches using triggered electromyography. The threshold current recorded was not significantly different between the two systems (P > 0.1, paired t test) nor was the difference (0.16 mA) clinically significant. CONCLUSION: No difference was found between the thresholds detected with either system. There is however, a significant difference in the costs of the two probe systems.

Assessment of nerve involvement in the lumbar spine: agreement between magnetic resonance imaging, physical examination and pain drawing findings.

BACKGROUND: Detection of nerve involvement originating in the spine is a primary concern in the assessment of spine symptoms. Magnetic resonance imaging (MRI) has become the diagnostic method of choice for this detection. However, the agreement between MRI and other diagnostic methods for detecting nerve involvement has not been fully evaluated. The aim of this diagnostic study was to evaluate the agreement between nerve involvement visible in MRI and findings of nerve involvement detected in a structured physical examination and a simplified pain drawing. METHODS: Sixty-one consecutive patients referred for MRI of the lumbar spine were - without knowledge of MRI findings - assessed for nerve involvement with a simplified pain drawing and a structured physical examination. Agreement between findings was calculated as overall agreement, the p value for McNemar's exact test, specificity, sensitivity, and positive and negative predictive values. RESULTS: MRI-visible nerve involvement was significantly less common than, and showed weak agreement with, physical examination and pain drawing findings of nerve involvement in corresponding body segments. In spine segment L4-5, where most findings of nerve involvement were detected, the mean sensitivity of MRI-visible nerve involvement to a positive neurological test in the physical examination ranged from 16-37%. The mean specificity of MRI-visible nerve involvement in the same segment ranged from 61-77%. Positive and negative predictive values of MRI-visible nerve involvement in segment L4-5 ranged from 22-78% and 28-56% respectively. CONCLUSION: In patients with long-standing nerve root symptoms referred for lumbar MRI, MRI-visible nerve involvement significantly underestimates the presence of nerve involvement detected by a physical examination and a pain drawing. A structured physical examination and a simplified pain drawing may reveal that many patients with "MRI-invisible" lumbar symptoms need treatment aimed at nerve involvement. Factors other than present MRI-visible nerve involvement may be responsible for findings of nerve involvement in the physical examination and the pain drawing.

Functional assessment of C-5 ventral rootlets by intraoperative electrical stimulation of the supraclavicular segment of the long thoracic nerve during brachial plexus surgery.

OBJECT: Anatomical and functional assessment of the intradural segment of the spinal nerves is imperative in brachial plexus surgery, as the repair of postganglionic elements in the setting of a confirmed nerve root avulsion is of no benefit. None of the current techniques to detect these avulsions can provide full information that ensures the functional status of the preganglionic segment of the roots. The objective of this study was to evaluate intraoperative electrical stimulation of the supraclavicular segment of the long thoracic nerve (LTN) as a method to differentiate C-5 nerve root extraforaminal rupture from its intradural avulsion. METHODS: The author performed a prospective analysis of data obtained in 14 patients presenting with the loss of C-5 nerve root function secondary to traumatic brachial plexus injury. The patients were divided into 2 groups: 8 patients in whom the intradural segment of C-5 nerve root was preserved (5 cases of closed traction injuries in whom the computed tomography [CT] myelograms confirmed the integrity of C-5 root and 3 cases of open sharp injuries) and a control group of 6 patients in whom CT myelography demonstrated avulsion of the root. RESULTS: The results of the intraoperative electrical stimulation of the LTN and the surgical outcome of each patient were recorded. The LTN electrical stimulation elicited serratus anterior muscle contraction in cases in which C-5 root was not avulsed, and there were no responses in patients whose radiological evaluation had demonstrated nerve root avulsion. In those patients in whom LTN stimulation proved to be positive, the C-5 root was used as a graftable stump to the suprascapular nerve and/or to the posterior division of the superior trunk. In these cases, favorable results were observed regarding arm abduction in all cases -- Medical Research Council Grades M3 (37%) and M4 (62%). In the control group, the C-5 root was not used as a donor stump and a multiple nerve transfer technique was adopted as the preferred surgical option. CONCLUSIONS: Intraoperative electrical stimulation of the supraclavicular segment of the LTN is a useful complementary method to test the functional status of the C-5 ventral rootlets. If the test is positive (that is, a response is present) it is indicative of extraforaminal rupture of the root, and if negative, it is suggestive of its avulsion.

Indomethacin blocks the nucleus pulposus-induced effects on nerve root function. An experimental study in dogs with assessment of nerve conduction and blood flow following experimental disc herniation.

Inflammatory mechanisms have been suggested to be involved in the basic pathophysiologic events leading to nerve root injury after local application of nucleus pulposus. To assess if these nucleus pulposus-induced effects could be blocked by anti-inflammatory treatment, 41 dogs were exposed to either incision of the L6-7 disc to induce experimental disc herniation with (n=12) or without (n=14) indomethacin treatment per os (5 mg/kg per day), and no incision with (n=5) or without (n=10) indomethacin. Intraneural blood flow and nerve conduction velocity were assessed after 7 days to evaluate the degree of nerve injury. Disc incision induced a reduction in nerve root and dorsal ganglion blood flow as well as nerve function, similarly to previous studies. However, simultaneous treatment with indomethacin efficiently blocked the negative effects on both blood flow and nerve conduction but had no effects per se. The present study thus indicates that inflammatory mechanisms may be of relevance in the pathophysiology of nucleus pulposus-induced nerve root injury and thereby also for sciatica.

Quantitative real-time RT-PCR assessment of spinal microglial and astrocytic activation markers in a rat model of neuropathic pain.

Activated spinal glial cells have been strongly implicated in the development and maintenance of persistent pain states following a variety of stimuli including traumatic nerve injury. The present study was conducted to characterize the time course of surface markers indicative of microglial and astrocytic activation at the transcriptional level following an L5 nerve transection that results in behavioral hypersensitivity. Male Sprague-Dawley rats were divided into a normal group, a sham surgery group with an L5 spinal nerve exposure and an L5 spinal nerve transected group. Mechanical allodynia (heightened response to a non-noxious stimulus) of the ipsilateral hind paw was assessed throughout the study. Spinal lumbar mRNA levels of glial fibrillary acidic protein (GFAP), integrin alpha M (ITGAM), toll-like receptor 4 (TLR4) and cluster determinant 14 (CD14) were assayed using real-time reverse transcription polymerase chain reaction (RT-PCR) at 4 h, 1, 4, 7, 14 and 28 days post surgery. The spinal lumbar mRNA expression of ITGAM, TLR4, and CD14 was upregulated at 4 h post surgery, CD14 peaked 4 days after spinal nerve transection while ITGAM and TLR4 continued to increase until day 14 and returned to almost normal levels by postoperative day 28. In contrast, spinal GFAP mRNA did not significantly increase until postoperative day 4 and then continued to increase over the duration of the study. Our optimized real-time RT-PCR method was highly sensitive, specific and reproducible at a wide dynamic range. This study demonstrates that peripheral nerve injury induces an early spinal microglial activation that precedes astrocytic activation using mRNA for surface marker expression; the delayed but sustained expression of mRNA coding for GFAP implicates astrocytes in the maintenance phase of persistent pain states. In summary, these data demonstrate a distinct spinal glial response following nerve injury using real-time RT-PCR.

A comparison of magnetic resonance imaging and neurophysiological studies in the assessment of cervical radiculopathy.

Neurophysiological studies (NPS) are often used by both neurosurgeons and neurologists to supplement neuroimaging findings in the diagnosis of cervical radiculopathy and in operative decision-making. The aim of this study was to assess whether nerve conduction and electromyographic studies added significant information to that obtained from high resolution MRI to warrant routine use. Over the 10-year period (1991-2001), we identified 48 patients who underwent both preoperative NPS and MRI for cervical radiculopathy. Sensitivity of MRI and NPS for diagnosing cervical radiculopathy was 93 and 42%, respectively. Whilst the positive predictive values for MRI and NPS were similar (91% versus 86%), the former had a higher negative predictive value (25% versus 7%). In only one case was the decision to operate based on NPS despite a negative MRI. We therefore suggest that in patients with clinical and MRI evidence of cervical radiculopathy, NPS has limited additional diagnostic value.

[Significance of unresolved financial compensation for the course of cervical root compression]. / Betydningen af uafklaret økonomisk kompensation for forløbet af nerverodstryk i nakken.

The aim of this study was to examine the influence of claims for financial compensation on the results of physiotherapeutic McKenzie treatment for cervical nerve root compression. This study was based on prospectively collected data for quality assurance purpose with baseline classification and included a follow-up postal questionnaire to measure the outcomes: Neck and arm pain, disability, use of analgesics and the perceived effect of the treatment registered by the patient. At baseline, patients with or without compensation issues were identical in regard to their neurological and clinical signs. The study showed that 6-12 months later there was no improvement in six out of seven patients with claims for compensation involvement, in contrast to the 21 patients without claims for financial compensation who all showed significant improvement. The results applied to all five outcome measures. In conclusion, compensation involvement seems to act as a negative factor on treatment results for patients with cervical nerve root compression who were treated conservatively.

Electrophysiologic assessment of acute polyradiculoneuropathy in dogs: comparison with Guillain-Barré syndrome in people.

Electrophysiologic investigations of motor and sensory nerve as well as ventral nerve root function were performed on 12 dogs with suspected acute canine polyradiculoneuropathy (ACP) at different stages and with different severity of disease. The most reliable electrophysiologic indicators of ACP were electromyographic changes (occurring in 100% of affected dogs), significantly decreased compound muscle action potential amplitudes (in 75, 90, and 100% of affected dogs at all sites along the sciatic/tibial, radial, and ulnar nerves, respectively), increased minimum F-wave latencies (67%), increased F ratios (92%), and decreased F-wave amplitudes (67%). These findings suggest that ACP represents a peripheral motor axonopathy, with demyelination and axonal involvement also occurring in ventral nerve roots. Evidence of peripheral demyelination was present in some dogs although it was overshadowed by the prominent axonopathy. ACP more closely resembles the acute axonal or intermediate forms of Guillain-Barré syndrome in people.

Personality assessment of patients with complex regional pain syndrome type I.

OBJECTIVE: There is controversy regarding the importance of psychological/psychiatric factors in the development of the Complex Regional Pain Syndrome (CRPS). Our objective was to determine whether CRPS type I patients were psychiatrically different from other chronic pain patients, with particular attention to personality pathology. DESIGN: A standardized clinical assessment of all major psychiatric categories, including personality disorders, was performed on 25 CRPS type I patients and a control group of 25 patients with chronic low back pain from disc-related radiculopathy. MEASURES: Both sections of the Structured Clinical Interview for the Diagnostic and Statistical Manual (3rd ed., rev.) and the visual analog scale. RESULTS: Both groups were similar in terms of pain intensity and duration. Statistical analysis showed both groups to have a significant amount of major psychiatric comorbidity, in particular major depressive disorder, and a high incidence of personality disorders. Therefore, intense chronic pain was associated with significant psychiatric comorbidity in both groups and in similar proportions. CONCLUSION: The high incidence of personality pathology in both groups may represent an exaggeration of maladaptive personality traits and coping styles as a result of a chronic, intense, state of pain.

Diagnostic value of different neurophysiological methods in the assessment of lumbar nerve root lesions.

OBJECTIVE: To investigate the sensitivity of a combination of different neurophysiological testing methods in patients with lumbar nerve root lesions. DESIGN AND SETTING: A prospective study was carried out in an electrodiagnosis laboratory on 57 patients with clinically proven lumbar radiculopathies. PATIENTS AND INTERVENTIONS: On 9 patients with L4 nerve root lesions, 31 patients with L5 nerve root lesions, and 17 patients with S1 nerve root lesions, extensive electromyography (EMG), nerve conduction studies, F-wave-deviations, and somatosensory evoked potentials (SEPs) were performed. RESULTS: In 93% of all patients, a pathological neurophysiological result was found. In L4 nerve root lesions, EMG was abnormal in 89%, dermatome SEPs were abnormal in 67%, and F-wave latencies were abnormal in 44%. In L5 nerve root lesions, a pathological result was found on EMG in 87%, in peroneus SEPs in 67%, and in F-wave latencies in 66%. In S1 nerve root lesions, the most sensitive results were from dermatome SEPs in 64%, followed by EMG in 53% and F-wave latencies in 24%. Nerve conduction study results were always normal. CONCLUSION: There are segment-specific neurophysiological results. It is possible to enhance testing sensitivity by a combination of different neurophysiologic testing methods. On these grounds, we recommend a segment-specific neurophysiological "diagnosis scheme" to corroborate the clinical diagnosis in lumbar nerve root lesions.

[Motor potentials evoked by magnetic stimulation--a tool for objective assessment of motor conduction along the spinal cord and its roots].

Magnetic stimulation of the motor cortex and nerve roots in conjunction with F-wave recording was used for assessment of central and peripheral motor conduction times in 98 patients suffering from myelopathy and cervical or lumbo-sacral radiculopathy. Significant prolongation of the central motor conduction times was found in the myelopathy group. The Motor Evoked Potential was of low amplitude and distorted shape. The amplitude of the F-wave was markedly increased. The main feature of the radiculopathy group was prolonged motor root conduction time as evident by delayed F-wave. Motor evoked potentials proved to be a reliable objective tool in the functional evaluation of conduction along the spinal cord and its roots.

A critical assessment of clinical diagnosis of disc herniation in patients with monoradicular sciatica.

The diagnostic power or clinical parameters in the diagnosis of lumbar disc herniation in patients with monoradicular pain was evaluated in a prospective study with a 100% verification of the diagnosis. Eighty patients with monoradicular pain corresponding to the fifth lumbar or the first sacral nerve root were included. Pre-operatively a number of clinical parameters were recorded and compared to the intra-operative finding of a disc herniation. The parameters were analysed by receiver operating characteristic (ROC) curves. Results from the available literature were analysed by ROC curves for comparison. In 76% of the cases a disc herniation was discovered. The level of the disc herniation was correctly predicted in 93% of these cases by the location of the pain alone or supplemented by neurological signs. Apart from radicularly distributed pain, all parameters in the present study and in the literature had no or low diagnostic accuracy. Thus, in patients with monoradicular sciatica further clinical parameters do not add to the diagnosis of lumbar disc herniation.

Neuroradiologic and electrophysiologic assessment of cervical spondylotic amyotrophy.

Dissociated motor loss due to cervical spondylosis and disc herniation was evaluated in 10 patients who presented with left deltoid paresis in the absence of sensory deficits or myelopathy. All of these cases underwent cervical anterior decompression. Based on magnetic resonance imaging, computed tomography myelography, and computed tomography discography, patients were divided into two pathologic types: The first showed focal bony spur and disc herniation with axial cord rotation and nerve root compression, and the second demonstrated ventral cord flattening. Electrophysiologic studies included evoked spinal potentials, motor evoked potentials, and evoked muscle action potentials. Motor evoked potentials, recorded epidurally from the ventral aspect of the thecal sac and the nerve root within the anterior discectomy or vertebrectomy sites, proved clinically most useful. Combining the latest available neuroradiologic and electrophysiologic information, 4 types of neural injury associated with deltoid pareses were identified in the 10 patients. The first included isolated C5 nerve root lesions; the second, C6 nerve root lesions; the third, both C5 and C6 nerve root lesions, and finally, intrinsic cord pathology.