Extradural spinal arachnoid cysts associated with spina bifida occulta

INTRODUCTION

Spinal extradural arachnoid cysts are an uncommon cause of neural compression in children. Even more uncommon is the association of such cysts with spina bifida occulta.

MATERIAL

Two girls, 12 and 8-years-old, presented with left leg pain, deteriorating gait, clinical signs of left L5 and S1 root compression, without bladder or bowel symptoms. The first patient had left foot drop. The second patient had muscle wasting and smaller left foot with pes cavus. Radiographs showed spina bifida occulta of S1 in both. MRI revealed an extradural cyst at the S1 level, indenting the thecal sac and the L5 and S1 roots. At operation in both patients a large arachnoid cyst arising from a small dural defect in the axilla of the left S1 root was compressing and displacing it and the dural sac. It was removed and the defect was repaired. The first patient improved with complete recovery of the foot drop. An MRI at 12 months showed no cyst recurrence. The second patient made good recovery initially, but at 10 months developed recurrent symptoms. An MRI scan showed recurrence of the cyst with root compression. On repeat exploration a different dural defect was identified in a more anterior position and was repaired.

DISCUSSION

The coexistence of extradural arachnoid cyst and corresponding bifid spinal segment has not been described previously. It raises the suspicion that the dural defect giving rise to the arachnoid cyst may be due to segmental dural dysgenesis in the context of the dysrhaphic neuroectodermal malformation.

Do diagnostic segmental nerve root blocks in chronic low back pain patients with radiation to the leg lack distinct sensory effects? A preliminary study

BACKGROUND

The present preliminary study documents the effects of a selective nerve root block (SNB) with short or long acting local anaesthetic compared with baseline measurements in patients with chronic low back pain radiating to the leg with maximum pain in one dermatome (L4).

METHODS

Ten consecutive patients underwent 20 controlled SNBs at L4 with ropivacaine 0.25% and lidocaine 1% in a prospective, randomized, double blind, crossover fashion. Baseline measurements included sensory function (assessed by pinprick on both unaffected and painful leg) and pain (Verbal Numeric Rating Scale; VNRS, 0-10). A change in size of areas with altered sensory function >10% and a VNRS change of 2 points were considered clinically significant. P-values<0.05 were considered statistically significant.

RESULTS

Asymptomatic hypoaesthesia, variable in extent and non-dermatomal in distribution, was present in seven patients at baseline. It appeared to be more extensive and distal with longer duration of pre-existing pain. SNB produced no consistent changes in extent and distribution of hypoaesthetic areas. Change in VNRS did not correlate with the extent of pre-block or post-block hypoaesthesia. No differences in effects were found between lidocaine and ropivacaine.

CONCLUSIONS

Pre-block assessment of sensory function is essential to assess the net effect of SNBs. In this small study group, SNBs failed to demonstrate uniform or distinct effects on sensory function.

Responses to lumbar magnetic stimulation in newborns with spina bifida

Searching for a tool to quantify motor impairment in spina bifida, transcranial and lumbar magnetic stimulation were applied in affected newborn infants. Lumbar magnetic stimulation resulted in motor evoked potentials in both the quadriceps muscle and the tibialis anterior muscle in most (11/13) subjects. However, transcranial magnetic stimulation did not lead to any response at all. A strong left-to-right correlation existed for amplitude and for latency. Lumbar magnetic stimulation proved to be applicable in newborn infants with spina bifida. Although current concepts regarding spina bifida suppose lower motor neuron dysfunction, the results of this study suggest that lower motor neuron integrity is at least partly preserved after birth. Transcranial magnetic stimulation does not lead to responses in healthy newborn infants because of insufficient synaptogenesis, myelinogenesis, and axon thickness. Therefore, conclusions on upper motor neuron function in spina bifida cannot be drawn. To what extent the method used here can achieve the aim of quantifying motor impairment is a matter of further study.

Late appearance of dropped head syndrome after radiotherapy for Hodgkin's disease

We present three cases of dropped head syndrome that occurred as a complication of mantle field (i.e., lymph nodes of the neck, axillae, and mediastinum) or whole-body radiation therapy for Hodgkin's disease. These cases are characterized by a late onset (2-27 years after radiation treatment), fibrosis, and contraction of the anterior cervical muscles, and atrophy of the posterior neck and shoulder girdle. This report adds to the increasing literature about the late neurological complications of radiation therapy and describes a previously unrecognized cause of dropped head syndrome.

Ewing's Sarcoma in the Spinal Nerve Root: A Case Report and Review of the Literature

Ewing's sarcoma (ES) is a highly malignant tumor composed of uniform small round cells. Recently, a single biologic entity, Ewing's sarcoma family of tumors (ESFT) has been accepted. The entity includes ES, extraskeletal Ewing's sarcoma (EES) and primitive neuroectodermal tumor (PNET). ESFT cells have immunoreactivity for CD99, an antigen determined by the MIC2 gene. Most ESFT has the (11;22) (q24;q12) translocation. The translocation results in the fusion of the EWS gene with the transcription factor gene FLI1 which has been considered a hallmark of ESFT. We present an extremely unusual case with ESFT in a spinal nerve root mimicking a neurogenic dumbbell tumor. A male aged 20 years noticed pain in his right buttock. Magnetic resonance imaging (MRI) revealed a mass in the right L5/S intervertebral foramen and the lesions in the sacrum. Surgery was performed with a presumptive diagnosis of a nerve sheath tumor. At surgery, the tumor was located in the right L5 nerve root sleeve. The sacral lesions were observed closely. At one month after surgery, radiologically multiple lesions were detected in the pelvic bones. Microscopically the lesions from the root and ilium were composed of small round cells immunoreactive for CD99. Reverse transcription-polymerase chain reaction detected transcripts resulting from the fusion of the EWS gene with FLI1 genes in the iliac lesion. Immunoreactivity for CD99 and detection of the EWS-FLI1 hybrid transcripts are important for the correct diagnosis of ESFT arising in an unusual location.

Alteration of central motor excitability in a patient with hemimasticatory spasm after treatment with botulinum toxin injections

Hemimasticatory spasm (HMS) is a condition characterized by paroxysmal involuntary contraction of masticatory muscles. We performed an electrophysiological investigation of a single patient with HMS to identify any pathophysiological changes associated with the condition. We identified a delayed M wave and jaw jerk on the affected side and an absent masseteric silent period during spasm. Botulinum toxin injections successfully treated the clinical symptoms and resulted in a significant reduction in the excitability of the blink reflex recovery cycle. These data suggest that HMS may be due to ectopic activity in the motor portion of the trigeminal nerve that is capable of inducing changes in the excitability of central reflex pathways. These changes can be altered by successful treatment with botulinum toxin.

Efficacy of surgical decompression in regard to motor recovery in the setting of conus medullaris injury

BACKGROUND/OBJECTIVE

An assessment of neurological improvement after surgical intervention in the setting of traumatic conus medullaris injury (CMI).

METHODS

A retrospective evaluation of a cohort of patients with a blunt traumatic CMI from T12 to L1. The neurologic and functional outcomes were recorded from the acute hospital admission to the most recent follow-up. Data collected included age, level of injury, neurologic examination according to the Frankel grading system and motor index score, and the mechanism and timing of CMI decompression.

RESULTS

A total of 24 patients with a mean age of 27 years (men, 87%) were identified. The most common level of bony injury was L1, and the most frequent mechanism of injury was a motor vehicle crash. Before surgical intervention, 16 of 24 patients (66.7%) had a complete neurological deficit below the level of injury. The median interval from injury to surgery was 6 days (range, 7 hours to 390 days). Decompression, fusion, and adjunctive internal fixation were the most common surgical procedures. Median length of follow-up was 32 months after surgery. Improvement in spinal cord and bladder function was seen in 41.6% and 63.6% of patients, respectively. Root recovery was seen in 83.3% of patients.

CONCLUSIONS

In the setting of CMI, no correlation between the timing of surgical decompression and motor improvement was identified. Root recovery was more predictable than spinal cord and bladder recovery.

[Pain patterns of disc lesions of the lumbar spine]

AIM

The aim of this study was to find out the reliability of several dermatomic maps (description of pain pattern within a nerve root lesion) according to the respective segmental area.

METHODS

Different studies which deal with pain pattern caused by disc lesions were searched for with MedLine support and then reviewed.

RESULTS

A clear correlation between the pain projections of the lumbar spine does not seem to exist. A contradiction of the most common pain projection (S1) and operated disc (L4/5) is described.

CONCLUSION

Even though there are studies of high scientific design and value (Nitta H, Wolff A) the pain pattern of dermatomic maps is only of limited value for the definition of the affected segment.

Neoplastic lumbosacral radiculoplexopathy in prostate cancer by direct perineural spread: An unusual entity

Neoplastic lumbosacral plexopathy occurs with some abdominal and pelvic malignancies. Patients present with severe pain radiating from the low back down to the lower extremities, and this progresses to weakness. Neoplastic lumbosacral plexopathy is virtually always associated with known malignancy or obvious pelvic metastatic disease. Uncommonly, prostate cancer can present as a lumbosacral plexopathy occurring through direct pelvic spread. We describe two cases of lumbosacral radiculoplexopathy from infiltrative prostate cancer without evidence of other pelvic or extraprostatic spread. The probable etiology of tumor spreading along prostatic nerves into the lumbosacral plexus (i.e., perineural spread) is discussed as are the potential mechanisms for this unusual mode of cancer dissemination.

Functional and morphological changes of lumbar nerve roots induced by mechanical compression or the nucleus pulposus in contact with the root: analysis of fiber size-dependent vulnerability in rabbits

The variation in symptoms of spinal nerve root damage may be caused by the difference of the size of damaged nerve fiber or difference between the mechanical influence and some chemical factors. We studied the relative vulnerability of small versus large myelinated fibers to a focal compression and/or an application of nucleus pulposus. We prepared the mechanical compression model by clipping the nerve root and the nucleus pulposus model by applying autologous nucleus pulposus on the nerve root in a rabbit and evaluated nerve root damage with respect to its fiber diameter. Nerve conduction velocity (NCV) of large myelinated nerve fiber was reduced significantly in every group compared with a sham operation group (sham) after 1 day in compression, but in the nucleus pulposus group (NP) the velocity was reduced significantly compared with sham only after 7 days. Histologic examination revealed that the number of damaged large fibers increased significantly in the compression group compared with sham after 3 days, but there was no difference in NP. NCV of small myelinated nerve fibers was reduced significantly in both the compression and NP groups compared with sham after 7 days. Histologic study showed the number of damaged small fibers increased significantly in the compression group compared with sham after 7 days. However, in the NP group the number of damaged fibers did not increase compared with sham. In conclusion, large myelinated nerve fiber was damaged earlier than small myelinated nerve fiber by compression, while nerve fiber damage caused by only the nucleus pulposus had no relation to nerve fiber size.

Nerve root distribution of deltoid and biceps brachii muscle in cervical spondylotic myelopathy: a potential risk factor for postoperative shoulder muscle weakness after posterior decompression

To investigate the nerve root distribution of deltoid and biceps brachii muscle, compound muscle action potentials (CMAPs) were recorded intraoperatively following nerve root stimulation in cervical spondylotic myelopathy. A total of 19 upper limbs in 12 patients aged 55-72 years (mean, 65.5 years) with cervical spondylotic myelopathy were examined. CMAPs were recorded from deltoid and biceps brachii muscle following C5 and C6 root stimulation. Although both C5 and C6 roots were innervated for deltoid and biceps brachii muscle in all subjects, the amplitude ratio of CMAPs (C5/C6) differed individually depending on the symptomatic intervertebral levels of the spinal cord. The C5 root predominantly innervated both deltoid and biceps brachii in patients with symptomatic cord lesions at the C4-C5 intervertebral level compared to patients with symptomatic cord lesions at the C5-C6 intervertebral level. Although no patients sustained postoperative radiculopathy in our study, severe weakness and unfavorable recovery are expected when the C5 root in patients with C4-C5 myelopathy is damaged. From the electrophysiological aspect, C4-C5 cord lesions are likely to be a potential risk factor for postoperative shoulder muscle weakness in patients with compressive cervical myelopathy.

Neonatal Chronic Hind Paw Inflammation Alters Sensitization to Intradermal Capsaicin in Adult Rats: A Behavioral and Immunocytochemical Study

The present studies were conducted to examine functional consequences of postnatal chronic inflammation, initiated during a critical developmental period, on capsaicin-evoked hyperalgesia and neuronal activation in adulthood. Rats received a unilateral intraplantar injection of complete Freund's adjuvant (CFA; diluted 2:1 in saline) on postnatal day 0 (P0-CFA) or 14 (P14-CFA). Separate groups received an equivalent volume of saline on P0 (P0-vehicle) or were untreated (P0-untreated). Increases in capsaicin-evoked thermal and mechanical hyperalgesia and allodynia were observed in adult P0-CFA-treated rats relative to control conditions. By contrast, this enhancement was absent in P14-CFA-treated rats, suggesting that the developmental period differentially affects the appearance of the observed behavioral phenotype. Capsaicin-evoked nocifensive behavior was also lower in P14-CFA-treated rats relative to P0-CFA-treated rats. Capsaicin-evoked Fos protein expression was increased in the superficial and neck regions of the dorsal horn of adult P0-CFA-treated rats relative to P0-vehicle-treated rats. These changes were absent in the nucleus proprius and ventral horn. The present data are consistent with the hypothesis that neonatal chronic inflammation permanently alters sensitivity to pain in adulthood, consistent with modulation of primary afferent activation and central sensitization in response to a subsequent nociceptive challenge in adulthood.

PERSPECTIVE

Chronic inflammation during development can induce profound alterations in sensory processing later in life. Here we show that long-term inflammation initiated at critical developmental stages sensitizes both behavioral and neuronal responses to nociceptor stimulation in adulthood. An ongoing sensitization of the spinal cord is induced by the postnatal inflammatory insult.

Multifocal motor sensory demyelinating neuropathy: Inflammatory demyelinating polyradiculoneuropathy

The authors present two cases that provide the first autopsy findings in multifocal acquired demyelinating sensory and motor neuropathy (MADSAMN). Both cases documented multifocal but asymmetric demyelinating neuropathy with rare axonal degeneration. One case clearly documented an inflammatory polyradiculoplexoneuropathy, confirming the inflammatory nature of this neuropathy. This study showed that MADSAMN is an inflammatory demyelinating polyradiculoneuropathy that shares histologic features observed in chronic inflammatory demyelinating polyradiculoneuropathy and multifocal motor neuropathy (MMN), suggesting a similar immunopathogenesis for these entities.

Intracisternal neurinoma of the C1 posterior root

We report a rare intracisternal C1 posterior root neurinoma in a 35-year-old man without neurofibromatosis who presented with headache, nuchal pain, bilateral motor weakness of the upper extremities, and numbness in the right distal upper extremity. CT and MRI study showed a 20-mm intracisternal lesion at the foramen magnum. At surgery, there was an anastomosis between the C1 posterior root and a spinal accessory nerve at the site of the tumor; the root from the collateral sulcus of this C1 root was absent. Postoperatively, the patient remains free of symptoms. Foramen magnum neurinomas have been described as accessory nerve tumors. We present new anatomical consideration regarding this lesion.

An outcomes analysis of the treatment of cervical pseudarthrosis with posterior fusion

STUDY DESIGN

A retrospective review of 33 consecutive patients treated with posterior fusion and selective nerve root decompression for the treatment of pseudarthrosis following anterior cervical discectomy and fusion.

OBJECTIVES

Use standardized outcome measures to evaluate the results of posterior fusion with selective nerve root decompression as a treatment option for symptomatic pseudarthrosis of the cervical spine.

SUMMARY OF BACKGROUND DATA

Pseudarthrosis after anterior cervical discectomy and fusion has been recognized as a cause of continued cervical pain and unsatisfactory outcomes. Debate continues as to whether a revision anterior approach or a posterior fusion procedure is the best treatment for symptomatic cervical pseudarthrosis. To our knowledge, standardized outcome measures have not been used to evaluate the results of either surgical treatment option; therefore, it is difficult to evaluate outcomes in these patients, let alone compare surgical treatment options. Data on fusion rates in these two surgical treatment groups suggest a trend of a higher fusion rate with utilization of a posterior revision procedure, but the largest study to date includes the study of only 19 patients treated with a posterior fusion.

METHODS

Thirty-three consecutive patients with symptomatic pseudarthrosis following anterior cervical discectomy and fusion were treated with selective nerve root decompression and posterior fusion using iliac crest or local bone graft as well as posterior wiring and/or lateral mass plating. The average follow-up period was 46 months (range, 20-86 months). Patients were assessed using physical examination, flexion-extension lateral radiographs, and standardized outcome measures including the SF-36, Arthritis Impact Measurement Scales 2, and Cervical Spine Outcomes Questionnaire.

RESULTS

All 33 patients (100%) demonstrated a solid fusion at their most recent follow-up, and all 33 patients noted significant improvement in their preoperative symptoms. No difference in fusion status was noted between those treated with iliac crest versus patients treated with local bone graft--all had a solid fusion; 72% of the patients were satisfied with the result of their surgery. Cervical Spine Outcomes Questionnaire pain scales demonstrated 52% of patients reported mild or nopain at follow-up, whereas 20% described their pain as "discomforting" and 28% of the patients continued to report moderate to severe pain.

CONCLUSIONS

This is the first study to our knowledge to use standardized outcome measures to assess clinical outcome in patients treated with posterior fusion for pseudarthrosis after anterior cervical discectomy and fusion. Patients and surgeons need to understand the potential for success with this revision procedure but also be aware of the relatively high rate of continued moderate to severe pain observed in this patient population even after a solid fusion is achieved. All of the patients in this study fused with a single posterior fusion procedure, further supporting the relatively higher fusion rates observed in the literature using posterior fusion as a treatment for cervical pseudarthrosis. Our results also support the ability of surgeons to use local bone graft without iliac crest in a posterior fusion for cervical pseudarthrosis and therefore avoid the morbidity associated with iliac crest bone graft harvest.

Ectopic firing due to artificial venous stasis in rat lumbar spinal canal stenosis model: a possible pathogenesis of neurogenic intermittent claudication

STUDY DESIGN

An electrophysiologic analysis was performed on a chronic lumbar spinal stenosis model of rats. The effects of venous stasis on ectopic firing originating in the nerve root were investigated.

OBJECTIVES

To elucidate the mechanisms of neurogenic intermittent claudication in lumbar spinal canal stenosis.

SUMMARY OF BACKGROUND DATA

Neurogenic intermittent claudication has been known as a characteristic symptom of lumbar spinal canal stenosis (LSCS), but the pathogenesis is poorly understood. Venous stasis of cauda equina has been speculated as a possible factor in the development of symptoms of the lower extremities while walking. On the other hand, ectopic firing originating in the dorsal root ganglia is thought to play an important role in the development of radicular pain or abnormal sensation. However, a direct association between venous stasis and ectopic firing has been never demonstrated.

METHODS

Using 10 Wistar rats, the LSCS group was prepared by inserting two silicone strips into the L3 and L5 dorsal epidural spaces. Another 10 animals were treated without silicone insertion as a sham group. Fourteen days later, the ectopic firing originating in the L5 nerve root was antidromically recorded from the distal stump of the severed sural nerve. After recording initial spontaneous firing, the posterior vena cava was clamped for 60 seconds to simulate a transient venous stasis and the changes in firing were analyzed.

RESULTS

None of the animals in the sham group showed a significant change in firing due to venous stasis. In contrast, most animals in the LSCS group showed a marked increase in firing during the venous stasis with some latency and then returned to the initial firing state after the release of the clamp. This phenomenon was repeated as long as the animals were maintained.

CONCLUSIONS

We demonstrated that ectopic firing was elicited by venous stasis only in the LSCS animals. Therefore, the venous stasis may be a major factor of neurogenic intermittent claudication.

Spinal intradural extramedullary haemangioma: MRI and neurosurgical findings

Haemangiomas, have rarely been encountered in the spinal intradural extramedullary space and the MRI findings of this entity have been described only in a few cases. We present the Magnetic Resonance Imaging (MRI) and surgical findings of a rare case of intradural extramedullary cavernous angioma located at the T1-T2 level in a 65-year-old man presented progressive paraparesis and upper thoracic back pain. On MRI, a well-circumscribed intradural solid mass, 1 cm in diameter, was detected and another enhancing nodular mass was found at the nerve roots of the cauda equina. The thoracic spinal lesion was removed and the histological diagnosis confirmed cavernous haemangioma. Although very uncommon, haemangioma should be included in the differential diagnosis when a spinal intradural extramedullary lesion is discovered and some neuroradiological findings could allow a presumptive diagnosis.

Lumbar disk herniation with contralateral symptoms

The aim of the study is to determine if leg pain can be caused by contralateral lumbar disk herniation and if intervention from only the herniation side would suffice in these patients. Five patients who had lumbar disk herniations with predominantly contralateral symptoms were operated from the side of disk herniation without exploring or decompressing the symptomatic side. Patients were evaluated pre- and postoperatively. To our knowledge, this is the first reported series of such patients who were operated only from the herniation side. The possible mechanisms of how contralateral symptoms predominate in these patients are also discussed. In all patients, the shape of disk herniations on imaging studies were quite similar: a broad-based posterior central-paracentral herniated disk with the apex deviated away from the side of the symptoms. The symptoms and signs resolved in the immediate postoperative period. Our data clears that sciatica can be caused by contralateral lumbar disk herniation. When operation is considered, intervention only from the herniation side is sufficient. It is probable that traction rather than direct compression is responsible from the emergence of contralateral symptoms.

Vagus nerve stimulation for induced spinal cord seizures: insights into seizure cessation

OBJECT

Vagus nerve stimulation is known to decrease the frequency, duration, and intensity of some types of intracranial seizures in both humans and animals. Although many theories abound concerning the mechanism for this action, the true cause remains speculative. To potentially elucidate a pathway in which vagus nerve stimulation aborts seizure activity, seizures were initiated not in the cerebral cortex but in the spinal cord and then vagus nerve stimulation was performed.

METHODS

Ten pigs were anesthetized and placed in the lateral position, and a small laminectomy was performed in the lumbar region. Topical penicillin, a known epileptogenic drug to the cerebral cortex and spinal cord, was applied to the dorsal surface of the exposed cord. With the exception of two animals that were used as controls, once seizure activity was discernible via motor convulsion or increased electrical activity the left vagus nerve, which had been previously isolated in the neck, was stimulated. Following multiple stimulations of the vagus nerve and with seizure activity confirmed, the cord was transected in the midthoracic region and vagus nerve stimulation was performed. Vagus nerve stimulation resulted in cessation of spinal cord seizure activity in all (87.5%) but one experimented animal. Transection of the spinal cord superior to the site of seizure induction resulted in the ineffectiveness of vagus nerve stimulation to cause cessation of seizure activity in all study animals.

CONCLUSIONS

The effects of vagus nerve stimulation on induced spinal cord seizures involve descending spinal pathways. The authors believe that this experiment is the first to demonstrate that spinal cord neuronal hyperactivity can be suppressed by stimulation of a cranial nerve. These data may aid in the development of alternative mechanisms for electrical stimulation in patients with medically intractable seizures. Further studies are now necessary to isolate which specific tracts, nuclei, and neurotransmitters are involved in this process.

Effects of lumbar sympathectomy on pain behavioral changes caused by nucleus pulposus-induced spinal nerve damage in rats

It has been suggested that lumbar sympathectomy can reduce pain behavior, including mechanical allodynia and thermal hyperalgesia, caused by ligation of the spinal nerve. One well-characterized model, which involves application of nucleus pulposus to the spinal nerve and displacement of the adjacent nerve, shows behavioral changes in rats. However, there have been no previous reports regarding sympathectomy performed in this model. Disk incision and adjacent spinal nerve displacement were performed with (n=6) or without (n=6) sympathectomy. Sham surgery was also performed with (n=6) or without (n=6) sympathectomy. The animals were tested for 3 days before surgery and on days 1, 3, 7, 14, and 21 after surgery. Non-noxious mechanical thresholds were tested by determining the hind paw withdrawal response to von Frey hair stimulation of the plantar surface of the footpad using a touch stimulator. Thermal nociceptive thresholds were tested using a sensitive thermal-testing device. While rats in the disk incision with displacement surgery group showed allodynia and hyperalgesia after surgery on the experimental side, sympathectomized animals did not. No allodynia was observed in the sham groups. Sympathectomy seemed to prevent the pain behavioral changes caused by the combination of disk incision and nerve displacement.

Postinfectious inflammatory disorders: Subgroups based on prospective follow-up

BACKGROUND

Acute disseminated encephalomyelitis (ADEM) refers to a monophasic acute multifocal inflammatory CNS disease. However, both relapsing and site-restricted variants, possibly associated with peripheral nervous system (PNS) involvement, are also observed, and a systematic classification is lacking.

OBJECTIVE

To describe a cohort of postinfectious ADEM patients, to propose a classification based on clinical and instrumental features, and to identify subgroups of patients with different prognostic factors.

METHODS

Inpatients of a Neurologic and Infectious Disease Clinic affected by postinfectious CNS syndrome consecutively admitted over 5 years were studied.

RESULTS

Of 75 patients enrolled, 60 fulfilled criteria for ADEM after follow-up lasting from 24 months to 7 years. Based on lesion distribution, patients were classified as encephalitis (20%), myelitis (23.3%), encephalomyelitis (13.3%), encephalomyeloradiculoneuritis (26.7%), and myeloradiculoneuritis (16.7%). Thirty patients (50%) had a favorable outcome. Fifteen patients (25%) showed a relapsing course. Poor outcome was related with older age at onset, female gender, elevated CSF proteins, and spinal cord and PNS involvement. All but two patients received high-dose steroids as first-line treatment, with a positive response in 39 (67%). Ten of 19 nonresponders (53%) benefited from high-dose IV immunoglobulin; 9 of 10 had PNS involvement. The data were not controlled.

CONCLUSIONS

A high prevalence of "atypical variants" was found in this series, with site-restricted damage or additional peripheral nervous system (PNS) involvement. Prognosis and response to steroids were generally good, except for some patient subgroups. In patients with PNS involvement and steroid failure, a favorable effect of IV immunoglobulin was observed.

Belly dance syndrome due to spinal myoclonus

We report on a case of spinal myoclonus resembling a belly dance syndrome.

Transforaminal steroid injections in the treatment of cervical radiculopathy. A prospective outcome study

BACKGROUND

The aim of this study was to assess if transforaminal steroid injections applied to cohort of patients waiting for cervical disc surgery, reduce the pain of cervical radiculopathy and hence reduce the need for surgical intervention. Cervical radiculopathy due to cervical disc herniation or spondylosis is a common indication for cervical disc surgery. Surgery is however not always successful, and is not done without risk of complications. Transforaminal injection of steroids has gained popularity due to the rationale that inflammation of the spinal nerve roots causes radicular pain, and therefore steroids placed locally should relieve symptoms.

METHODS

During a 12-month period, 21 secondary referral patients with unilateral cervical radiculopathy entered the study. Cervical disc herniation or spondylosis affecting the corresponding nerve root was demonstrated by appropriate investigation (MRI or myelography). The patients then received 2 transforaminal steroid injections, at 2 weeks interval, while waiting for operative treatment. The pain intensity (VAS), Odom's criteria and operative indications were registered at 6 weeks and 4 months.

FINDINGS

After receiving injection treatment 5 of the 21 patients decided to cancel the operation due to clinical improvement. A statistically significant reduction (0.02) in radicular pain score was simultaneously measured. This corresponds well with the reduction in operative requirements since radicular pain is the main indication for operative treatment. The responders experienced a long-lasting effect. Those responding positively however improved neck pain to the same extent as radicular pain, and patients with cervical spondylosis responded as positively as those with disc herniation.

INTERPRETATION

This prospective cohort study indicates a reduction in the need for operative treatment due to injection treatment. The clinical effect is measurable, and a statistically significant improvement of the radicular pain is registered. Routine transforaminal injection treatment prior to surgery seems rewarding, but the complication risk must be taken into consideration.

Clinical and radiological relationship between posterior lumbar interbody fusion and posterolateral lumbar fusion

BACKGROUND

Posterolateral lumbar fusion (PLF) is the most popular technique for stabilizing the lumbar spine. Biomechanically, PLF decreases segmental motion in the posterior column, which presumably reduces facet joint pain. Posterior lumbar interbody fusion (PLIF) may decompress nerve roots by distracting the collapsed disc space, and achieving optimal fusion in relation to load-bearing capacity. The purpose of the study was to examine the role of interbody fixation vs pedicle fixation in transverse lumbar fusion and to assess treated and adjacent disc space height changes over time.

METHODS

One hundred patients who underwent PLIF and noninstrumented transverse process fusion (n = 55) or instrumented PLF (n = 45) between 1996 and 1998 were evaluated retrospectively. Outpatient charts and follow-up films were reviewed. Bone fusion was determined using Brantigan and Steffee's classification and clinical outcome by the Prolo scale. Disc space heights at the fusion and adjacent levels were measured. Analysis of variance and chi(2) statistical techniques were used for data analysis.

RESULTS

Disc space height was increased and better maintained in PLIF patients. PLIF resulted in a nonsignificant tendency toward higher fusion rates. No differences in clinical and functional outcomes were found between the groups. There was no correlation between preservation of disc space height and clinical outcome.

CONCLUSIONS

Disc space height does not seem to impact clinical outcome in lumbar fusion, and efforts to maintain it may be unwarranted.

INTRAOPERATIVE RECORDING OF ELECTRONEUROGRAPHIC SIGNALS FROM CUFF ELECTRODES ON EXTRADURAL SACRAL ROOTS IN SPINAL CORD INJURED PATIENTS

PURPOSE

A safe and reliable method for monitoring intravesical pressure on a long-term basis is needed for conditional electrical stimulation to be feasible as a treatment option for neurogenic detrusor overactivity in patients with a spinal cord injury. Therefore, we investigated the possibility of recording afferent nerve activity related to mechanical activity of the bladder and other pelvic organs from the extradural sacral nerve root in human.

MATERIALS AND METHODS

Nerve cuff electrodes were temporary placed on the extradural S3 sacral root in 6 spinal cord injured patients who underwent implantation of an extradural FineTech-Brindley Bladder System (Finetech Medical Lt., Welwyn Garden City, United Kingdom). The dorsal penile/clitoral nerve was electrically stimulated to evoke compound action potentials. Electroneurographic signals were recorded together with bladder and rectal pressure during mechanical stimulation of the dermatome rapid bladder filling and rectal distention, and during bladder contraction evoked by electrical stimulation of the contralateral sacral root.

RESULTS

Compound action potentials and electroneurographic responses during stimulation of the dermatome and rectum were present in all 6 patients and during bladder filling in 5 of 6. However, recorded responses from the bladder and rectum were small and mainly phasic in nature. Nerve responses following bladder contractions were present in 4 of 5 stimulated patients.

CONCLUSIONS

Afferent nerve activity from the dermatome, bladder and rectum can be recorded using cuff electrodes placed on the extradural S3 sacral root in humans but improvements in recording quality and sophisticated signal processing methods are needed for chronic application.

Comparison of effects of methylprednisolone and anti-CD11d antibody treatments on autonomic dysreflexia after spinal cord injury

Autonomic dysreflexia is a condition of episodic hypertension that develops after spinal cord injury (SCI). We previously showed that a two-day anti-inflammatory treatment with an anti-CD11d integrin monoclonal antibody (mAb), soon after SCI in rats, reduced the magnitude of dysreflexia for at least 6 weeks. Effects of methylprednisolone (MP), a commonly used neuroprotective treatment for SCI, on dysreflexia have never been examined. We compared the effects of a 2-day MP treatment and/or the anti-CD11d mAb on autonomic dysreflexia, elicited by colon distension, after clip-compression SCI at the 4th thoracic segment (T4) in rats. We assessed the effects of each treatment on the size of the calcitonin gene-related peptide (CGRP)-immunoreactive afferent arbour in the dorsal horn, as changes in this arbour can correlate with the development of dysreflexia. MP reduced autonomic dysreflexia by approximately 50% at 2 weeks after SCI, but this effect was lost by 6 weeks. At 2 weeks, the combined effects of MP and the mAb were not additive, reducing dysreflexia by approximately 50%. Neither MP nor the mAb treatment altered the area of CGRP-immunoreactive fibres in the lumbar cord, the crucial input region for dysreflexia initiated by colon distension. However, both treatments led to increased fibre areas in the T9 segment, correlated with greater tissue integrity and smaller lesions, delineated by inflammatory cells. In summary, MP only temporarily decreases autonomic dysreflexia after SCI. The early beneficial effects of both treatments on dysreflexia do not relate to changes in the CGRP-immunoreactive afferent arbour but may correlate with decreased lesion progression.

Bilateral traumatic neuroma of the anterior cervical nerve root: case report

STUDY DESIGN

Case report.

OBJECTIVES

A rare case of anterior cervical second root traumatic neuroma with no history of trauma is reported, and possible etiology is discussed.

SUMMARY OF BACKGROUND DATA

Traumatic neuroma is the reactive, nonneoplastic proliferation in the injured nerve. Several atypical locations of traumatic neuroma have been reported. To date, only 4 cervical traumatic neuroma cases with no history of trauma have been reported, and, to our knowledge, there is no case of bilateral cervical traumatic neuroma published in the literature.

METHODS

A patient with a history of neck and left upper extremity pain, who had hypoesthesia in left C2 dermatome on neurologic examination is presented. A left C2-C3 hemilaminectomy and tumor extirpation were performed.

RESULTS

A histopathologic study revealed features of a typical traumatic neuroma. The patient had no deficits on her postoperative neurologic examination, and her neck and left arm pain improved. The unusual location of this lesion and possible etiology of such a traumatic neuroma are discussed.

CONCLUSIONS

A rare case of anterior bilateral cervical second root traumatic neuroma with no history of trauma is reported. An unnoticed history of trauma may play an etiologic role in the development of these lesions.

Restoration of elbow flexion by performing contralateral lateral thoracic and thoracodorsal nerve transfers after experimental musculocutaneous nerve transection

OBJECT

The immediate transfer of the right lateral thoracic nerve (LTN) and the thoracodorsal nerve (TDN) to the transected left musculocutaneous nerve (MCN), leading to nerve cross-neurotization, was performed in cats to evaluate reinnervation of the biceps brachii muscle (BBM).

METHODS

Surgery to produce cross-neurotization of the MCN was performed in 12 cats (treatment group). Transection of the MCN was performed without attempts at neurotization in three cats (control group). Reinnervation of the BBM was assessed by performing electromyography (EMG) 6 months (14 cats) and 26 months (one cat) postsurgery. True Blue retrograde axonal tracing studies, tensile force measurements (muscle extensometry), and histopathological analyses were performed. All cats in the treatment group recovered voluntary contraction of the BBM and regained elbow flexion. Electromyography revealed no abnormal spontaneous activity in the BBM. Muscle evoked potentials were recorded in that muscle after right C-8 ventral branch stimulation. The muscle contraction strength in the left BBM varied from 108 to 557 g. The BBMs regained their normal appearances. The region of the MCN distal to the anastomosis displayed a normal histological appearance. Fluorescence was detected in the ventral horn of the spinal cord in the right C-8 and T-1 segments. In contrast, in all cats in the control group there was atrophy of the BBM, no EMG signal, and no clinical sign of recovery. There was no contraction of the BBM, no labeled neuron in the spinal cord, and the MCN displayed major degenerative changes.

CONCLUSIONS

These findings demonstrate that the LTN and TDN can be used to neurotize injured contralateral brachial plexus nerves and obtain successful reinnervation in cats.

Ligamentum flavum cysts causing incapacitating lumbar spinal stenosis

BACKGROUND

Cysts of the ligamentum flavum are rare and unusual causes of spinal compression.

METHODS

We report our experience of four cases of ligamentum flavum cysts occurring in the lumbar spine and discuss some of the possible etiologies and pathophysiologic mechanisms according to the available literature.

CONCLUSION

This entity is clearly different from the synovial facet-joints or ganglion cysts.

Regulation of neuropilin 1 by spinal cord injury in adult rats

Using RT-PCR, in situ hybridization, Western blotting, and immunofluorescence, we have analyzed the expression of neuropilin 1 (Np1) in two models of spinal cord injury (spinal cord hemisection and dorsal column crush) and following dorsal root rhizotomy in adult rats. Our results show that Np1 RNA and protein are up-regulated in the spinal cord after all these lesions but remain unaltered in the adjacent dorsal root ganglia. In control animals, Np1 levels in the spinal cord are low and appear to be localized mainly in blood vessels, motoneurons, and in the superficial layers of the dorsal horn. After DCC and rhizotomy, Np1 is expressed de novo around the injury and in the deafferentated dorsal horn, respectively, mainly by OX42-positive microglial cells. Both lesions affect the sensory projections, and interestingly a consistent increase of Np1 signal is additionally seen in the dorsal horn where these projections terminate. Unexpectedly, this increase is bilateral after unilateral rhizotomy.

Bowel and bladder continence, wound healing, and functional outcomes in patients who underwent sacrectomy

OBJECT

Total or partial sacrectomy is a rare procedure in patients with locally invasive tumors involving the sacrum; it may be associated with functional loss, such as bowel and bladder dysfunction and gait abnormality. In this study the authors examined functional outcome following sacrectomy.

METHODS

The authors reviewed the charts of 50 consecutive patients who had undergone sacrectomy between July 1993 and August 2002. There were 23 male and 27 female patients whose mean age was 46 years (range 13-86 years). Twelve patients with rectal cancer underwent a separate analysis. The patients without rectal cancer were divided into two groups: those who had undergone colostomy for bowel diversion (Group 1, six cases), and those who had not (Group 2, 32 cases). In Group 1 patients the median hospital length of stay (LOS) was 48.5 days (the 25th% and 75th percentiles are 26 and 58, respectively), and in Group 2 patients the median LOS was 18.5 days (the 25th and 75th percentiles are 8 and 41, respectively; p = 0.14). In Group 2 (non-rectal cancer without colostomy), LOS was greater in patients in whom a myocutaneous flap was used compared with those in whom no flap was used (36 days compared with 8.5 days, respectively; p = 0.0012); in patients with bowel incontinence the median LOS was significantly longer than that in patients with bowel continence (39 days compared with 8 days, respectively; p = 0.0026). The incidence of bowel incontinence in Group 2 was closely related to the integrity of the S-3 nerve root (p = 0.05).

CONCLUSIONS

Awareness of the association between S-3 nerve root resection and bowel and bladder incontinence may help surgeons' decision-making process.

Palsies of the fifth cervical nerve root after cervical decompression: prevention using continuous intraoperative electromyography monitoring

OBJECT

A desire to prevent complications resulting from spinal surgery led to the development of intraoperative monitoring. Intraoperative electromyography (EMG) provides useful diagnostic information regarding nerve root function during spinal and peripheral nerve surgeries. The C-5 nerve root is considered particularly vulnerable to injury during cervical surgery. Despite advances in techniques, the incidence of postoperative C-5 palsy has not changed.

METHODS

The authors reviewed prospectively collected data obtained in 161 patients who underwent 171 cervical procedures. In 116 procedures, operative monitoring was modified to include continuous C-5 EMG from the deltoid muscle. In cases in which spontaneous C-5 activity occurred, an appropriate change in operative manipulation was made. A historical control group consisted of a retrospective review of 55 procedures that were monitored using conventional techniques. In the retrospective cohort, four (7.3%) of 55 patients presented after undergoing surgery for C-5 nerve root palsy. In each patient conventional monitoring revealed unremarkable findings. In the prospective cohort, intraoperative spontaneous EMG activity necessitated a change in either positioning or operative technique in three cases. Only one patient (0.9%) experienced postoperative C-5 palsy. Postoperative C-5 palsy occurred in no patient in whom there was no intra-operative evidence of root irritation (p < 0.03, chi-square test).

CONCLUSIONS

The incidence of postoperative C-5 palsies was reduced from 7.3% to 0.9% due to intraoperative continuous EMG monitoring. No patient suffered a postoperative C-5 palsy when intraoperative evidence of root irritation was absent.

Discography-induced acute lumbar disc herniation: a report of five cases

The reported complication rate of provocative lumbar discography is low, ranging from 0-2.5%. We report five cases of acute lumbar disc herniation precipitated by discography, a previously unreported complication. The cases reported comprise of four men and one woman with ages ranging from 23-45 years. All developed an acute exacerbation of radicular leg pain following multilevel provocative lumbar discography. One patient developed an acute foot drop. Comparison of lumbar MRI scans before and after discography demonstrated either a new herniated disc fragment or an increase in size of a preexisting herniation in all cases. On review of each discogram study and pre-discogram MRI an annular tear or small disc herniation was noted in all cases. In each case the patients' symptoms failed to resolve necessitating surgical intervention in all cases. In conclusion, annular deficiency is an obvious predisposing factor to discogram related disc herniation. New onset or a persistent exacerbation of radicular symptoms following provocative discography merits further investigation.

Implementation of the TMS in the early stages of Parkinson's disease

47 PD patients were investigated with the single-pulse TMS to find out changes in motor evoked potential and motor conduction related to the stage of minimal motor symptoms and its further deterioration in groups with the different clinical types of the disease. The investigation revealed a markedly longer MEP duration along with the increased number of phases, than in controls, which were bilateral and advanced despite the minimal unilateral motor symptoms. There was also increased MEP amplitude in facilitation, with a higher degree of asymmetry, compared to controls. Patients with predominant rigid clinical forms had the further MEP duration and amplitude increase proportionally to bradikinesia and rigidity in the early stages of the disease. Patients with tremor predominant forms had no further changes in the MEP duration and amplitude, but had their motor CCT decreased in the early stages. Patients with the akinetic form were characterized by the asymmetric increase in the MEP Amplitude in relaxation and motor CCT shortening. Thus, TMS allows us to diagnose early the possible central motor changes secondary to Parkinson's disease, reveals the difference in compensational capacity according to the clinical type of the disease and helps in monitoring of the severity of motor changes in early stages.

Dorsal root entry zone (DREZ) localization using direct spinal cord stimulation can improve results of the DREZ thermocoagulation procedure for intractable pain relief

The dorsal root entry zone (DREZ) thermocoagulation for intractable pain after brachial plexus avulsion was performed in 21 patients. Good results in pain relief (relief of more than 75% of preoperative pain) were achieved in 62% of patients, whereby fair results (relief of 25-75% of preoperative pain) in 38% of patients. There was no patient with poor result (relief of less than 25% of preoperative pain). Complication rate was 14%. The whole patient population was subdivided into two groups (Group 1 and Group 2). Direct spinal cord bipolar stimulation and registration with the goal to localize DREZ was performed in the Group 2 consisting of 12 patients (n=12). The point on the spinal cord surface where no response after stimulus of low intensity was obtained was the site (the posterolateral sulcus) we identified as the most suitable point for the placement of radiofrequency thermocoagulation electrode. Comparing with the Group 1 consisting of nine patients (n=9), where the localization of DREZ by evoked potentials was not performed, significantly better effect of pain relief was recorded (P<0.05, odds ratio 10). There was no statistically significant difference (P>0.7) in complication rate in Group 1 and Group 2. Described electrophysiological technique is very helpful in identifying of DREZ and, in combination with microsurgical technique, can create DREZ thermocoagulation more effective.

Spastic bladder and spinal cord injury: seventeen years of experience with sacral deafferentation and implantation of an anterior root stimulator

INTRODUCTION

Spinal cord injured patients with a suprasacral lesion usually develop a spastic bladder. The hyperreflexia of the detrusor and the external sphincter causes incontinence and threatens those patients with recurrent urinary tract infections (UTI), renal failure, and autonomic dysreflexia. All of these severe disturbances may be well managed by sacral deafferentation (SDAF) and implantation of an anterior root stimulator.

MATERIAL AND METHOD

Between September 1986 to December 2002, 464 paraplegic patients (220 female, 244 male) received a SDAF-SARS. Almost exclusively the SDAF was done intradurally, which means with one operation field there can be done two steps (SDAF and SARS).

RESULTS

440 patients have a follow-up with 6.6 years (at least > 6 months-17 years). The complete deafferentation was successful in 94.1%. A total of 420 paraplegics may use the SARS for voiding (frequency 4.7 per day) and 401 use it for defecation (frequency 4.9 per week). Continence was achieved in 364 patients (83%). UTI declined from 6.3 per year preoperatively to 1.2 per year postoperatively. Kidney function presented stable. Early complications were 6 CSF leaks, 5 implant infections. Late complications with receiver or cable failures made us do surgical repairs in 34 paraplegics. A step-by-step program for trouble-shooting differentiates implant failure and myogenic or neurogenic failure.

CONCLUSION

SDAF is able to restore the reservoir function of the urinary bladder and to achieve continence. Autonomic dysreflexia disappeared in most of the cases. By means of an accurate adjustment of stimulation parameters it is possible to accomplish low resistance micturition. The microsurgical technique requires an intensive education. One has to be able to manage late implant complications.

Pathophysiology of disk-related low back pain and sciatica. II. Evidence supporting treatment with TNF-alpha antagonists

Strong evidence suggests that TNF-alpha may be among the chemical factors involved in disk-related sciatica. TNF-alpha is involved in the genesis of nerve pain in animal models and may promote pain-signal production from nerve roots previously subjected to mechanical deformation. In animal experiments, TNF-alpha has been identified in nucleus pulposus and Schwann cells. Local production of endogenous TNF-alpha may occur early in the pathogenic process. Exposure to exogenous TNF-alpha induces electrophysiological, histological, and behavioral changes similar to those seen after exposure to nucleus pulposus, and these changes are more severe when mechanical compression is applied concomitantly. TNF-alpha antagonists diminish or abolish abnormalities in animal models. Other cytokines may be involved also, as suggested by the potent inhibitory effects of compounds such as doxycycline. Two open-label studies in humans suggest dramatic efficacy of TNF-alpha antagonists in alleviating disk-related sciatica. In contrast, the results of the only controlled study available to date do not support a therapeutic effect of TNF-alpha antagonists. Thus, whether TNF-alpha antagonist therapy is warranted in patients with disk-related sciatica remains an open question, and further randomized controlled studies are needed.

Pathophysiology of disk-related sciatica. I.--Evidence supporting a chemical component

Sciatica in patients with disk disease was long ascribed to pressure put on the sciatic nerve root by a herniated disk. However, a role for chemical factors acting in conjunction with this mechanical insult is suggested by a number of clinical observations: disk surgery does not consistently provide pain relief, large disk herniations are not always symptomatic, severe pain may be present in patients without imaging evidence of nerve root compression, the severity of symptoms and neurological signs is not well correlated with the size of the disk herniation, and conservative therapy is often effective. Experimental studies have provided further evidence for a chemical component: disk herniations can undergo spontaneous resorption, the intervertebral disk is immunogenic, and mediators for inflammation have been identified within intervertebral disk tissue. The current pathophysiological theory incriminates proinflammatory substances secreted by the nucleus pulposus (NP). When preexisting or concomitant mechanical injury to a nerve root occurs, these substances can cause nerve root pain. Animal experiments have established that the NP can induce functional and structural nerve root abnormalities in the absence of mechanical compression and that this effect is mediated by substances located at the surface of NP cells. Methylprednisolone, diclofenac, indomethacin, doxycycline, and cyclosporine induce variable inhibition of this effect. Available information points to tumor necrosis factor-alpha (TNF-alpha) as the main candidate among substances potentially responsible for nerve root pain. Therefore, trials of TNF-alpha antagonists in patients with disk-related sciatica are warranted.

The effect of laser irradiation for nucleus pulposus: an experimental study

BACKGROUND

The radicular pain caused by disc herniation can be explained by two mechanisms: the compression of the nerve root by the herniated disc or the irritation of the nerve root due to chemical factors. Percutaneous laser disc decompression (PLDD) was introduced for the treatment of lumbar disc hernias in the 1980s. Decompression of the nerve root is assumed to be an effective therapeutic mechanism for PLDD. However, laser irradiation might reduce the chemical factors that cause nerve root irritation by altering intra-disc proteins. We used nerve conduction velocities (NCV) and levels of two chemical factors to evaluate the differences between the two groups in this in vivo study.

METHODS

All rabbits had the nerve root in contact with the leakage from the nucleus pulposus. One group underwent laser irradiation for the leaking nucleus pulposus including the incision site of the disc and nucleus pulposus itself. The levels of two chemical factors, prostaglandin E2 and phospholipase E2, in the intervertebral disc were measured before and after laser irradiation.

RESULTS

NCV in the laser-irradiated group was significantly faster than in the non-laser-irradiated group. The levels of chemical factors were significantly reduced after laser irradiation.

CONCLUSIONS

One of the mechanisms thought to be responsible for PLDD's effectiveness is a decrease in the chemical factors through protein alteration in the intervertebral disc by laser irradiation.

An artificial somatic-autonomic reflex pathway procedure for bladder control in children with spina bifida

PURPOSE

Neurogenic bladder is a major problem for children with spina bifida. Despite rigorous pharmacological and surgical treatment, incontinence, urinary tract infections and upper tract deterioration remain problematic. We have previously demonstrated the ability to establish surgically a skin-central nervous system-bladder reflex pathway in patients with spinal cord injury with restoration of bladder storage and emptying. We report our experience with this procedure in 20 children with spina bifida.

MATERIALS AND METHODS

All children with spina bifida and neurogenic bladder underwent limited laminectomy and a lumbar ventral root (VR) to S3 VR microanastomosis. The L5 dorsal root was left intact as the afferent branch of the somatic-autonomic reflex pathway after axonal regeneration. All patients underwent urodynamic evaluation before and after surgery.

RESULTS

Preoperative urodynamic studies revealed 2 types of bladder dysfunction- areflexic bladder (14 patients) and hyperreflexic bladder with detrusor external sphincter dyssynergia (6). All children were incontinent. Of the 20 patients 17 gained satisfactory bladder control and continence within 8 to 12 months after VR microanastomosis. Of the 14 patients with areflexic bladder 12 (86%) showed improvement. In these cases bladder capacity increased from 117.28 to 208.71 ml, and mean maximum detrusor pressure increased from 18.35 to 32.57 cm H2O. Five of the 6 patients with hyperreflexic bladder demonstrated improvement, with resolution of incontinence. Urodynamic studies in these cases revealed a change from detrusor hyperreflexia with detrusor external sphincter dyssynergia and high detrusor pressure to nearly normal storage and synergic voiding. In these cases mean bladder capacity increased from 94.33 to 177.83 ml, and post-void residual urine decreased from 70.17 to 23.67 ml. Overall, 3 patients failed to exhibit any improvement.

CONCLUSIONS

The artificial somatic-autonomic reflex arc procedure is an effective and safe treatment to restore bladder continence and reverse bladder dysfunction for patients with spina bifida.

Natural history of tumour-related sacral obliteration with nerve-root preservation

Benign aggressive bone tumours can present a dilemma when the definitive treatment options necessitate enormous and permanent functional deficits. Here, we present a case of a massive sacral giant-cell tumour causing dramatic skeletal obliteration, which was successfully treated with radical radiotherapy rather than ablative surgery. The excellent functional outcome highlights the importance of nerve-root preservation in selecting treatment modalities.

Immediate open anterior reduction and antero-posterior fixation/fusion for bilateral cervical locked facets

BACKGROUND

Bilateral cervical locked facets is a severe traumatic lesion, most frequently resulting in tetraplegia. The common treatment strategy has been an attempt of awake, closed reduction, adding general anesthesia, muscle relaxation and manual traction in difficult cases. In cases of failed closed reduction, open reduction has most commonly been performed by a posterior approach. Patients in the current series have been managed by immediate open anterior reduction and circumferential fixation/fusion. The technique is described and its potential advantages are discussed.

METHOD

Five consecutive patients with traumatic bilateral cervical locked facets are reported. The injury level was C4/5 in one and C5/6 in four patients. Four patients had initial tetraplegia, one patient was neurogically intact. All patients underwent immediate open anterior reduction by interbody distraction and gentle manual traction, followed by circumferential fixation/fusion. Mean follow-up was 15 months.

FINDINGS

Immediate anterior open reduction was rapidly and reliably achieved in all five patients. No surgical complication occurred. All patients showed fusion at the three-month follow-up. All four tetraplegic patients regained at least one functional root level, but remained tetraplegic.

CONCLUSION

Immediate open anterior reduction of bilateral cervical locked facets and combined antero-posterior fixation/fusion was safe and reliable. This treatment strategy avoids time loss and patient discomfort from attempted closed reduction by traction, obviates the need for external immobilization, and results in an excellent fusion rate.

Tibial nerve SEPs localized the lesion site in a patient with early tabes dorsalis

There is controversy regarding the initial pathology of tabes dorsalis. In a patient with early tabes dorsalis, tibial nerve somatosensory evoked potentials elicited normal P15, a delayed traveling peak in the lumbar bipolar leads, and absent subsequent components. Based on the comparison with normative data and stimulation at different intensities, the authors conclude that only the slower conducting antidromic motor volleys are preserved, whereas the dorsal root is damaged at its distal end.

Electrophysiological monitoring and identification of neural roots during somatic-autonomic reflex pathway procedure for neurogenic bladder

OBJECTIVE

To identify and separate the ventral root from dorsal root, which is the key for success of the artificial somatic-autonomic reflex pathway procedure for neurogenic bladder after spinal cord injury (SCI). Here we report the results of intra-operating room monitoring with 10 paralyzed patients.

METHODS

Ten male volunteers with complete suprasacral SCI underwent the artificial somatic-autonomic procedure under general anesthesia. Vastus medialis, tibialis anticus and gastrocnemius medialis of the left lower limb were monitored for electromyogram (EMG) activities resulted from L4, L5, and S1 stimulation respectively to differentiate the ventral root from dorsal root. A Laborie Urodynamics system was connected with a three channel urodynamic catheter inserted into the bladder. The L2 and L3 roots were stimulated separately while the intravesical pressure was monitored to evaluate the function of each root.

RESULTS

The thresholds of stimulation on ventral root were 0.02 ms duration, 0.2-0.4 mA, (mean 0.3 mA+/-0.07 mA), compared with 0.2-0.4 ms duration, 1.5-3 mA (mean 2.3 mA+/-0.5 mA) for dorsal root (P<0.01) to cause revoked potentials and EMG. Electrical stimulation on L4 roots resulted in the EMG being recorded mainly on vastus medialis, while stimulation on L5 or S1 roots caused electrical activities of tibialis anticus or gastrocnemius medialis respectively. The continuous stimulation for about 3-5 seconds on S2 or S3 ventral root (0.02 ms, 20 Hz, and 0.4 mA) could resulted in bladder detrusor contraction, but the strongest bladder contraction over 50 cm H2O was usually caused by stimulation on S3 ventral root in 7 of the 10 patients.

CONCLUSIONS

Intra-operating room electrophysiological monitoring is of great help to identify and separate ventral root from dorsal root, and to select the appropriate sacral ventral root for best bladder reinnervation. Different parameters and thresholds on different roots are the most important factors to keep in mind to avoid damaging the roots and to assure the best results.

Congenital absence of a lumbar pedicle presenting with contralateral lumbar radiculopathy

The authors describe a rare case of a congenital absence of the right L5 pedicle in a 54-year-old man presenting with low back pain and radicular pain of his left leg. Plain x-ray films, computed tomography scan (CT) after myelography, and three-dimensional CT revealed the absence of the L5 pedicle and anomaly of the L4-L5 facet joint on his right side. On the left side, there were severe degenerative changes that were thought to be the result of an overload and instability. The degenerative changes led to late-onset neurologic impairment of the contralateral side, which was treated with spinal fusion. To our knowledge, this is the first report of contralateral symptoms due to unilateral defect of the facet joint accompanied by aplasia of a pedicle.