Predictive value of computed tomographic myelography in obstetrical brachial plexus palsy

Preoperative radiologic studies to detect root avulsions of the brachial plexus caused by birth trauma are considered useful in assisting with surgical planning for reconstruction. In this study, the predictive value of computed tomographic (CT) myelography in detecting nerve root avulsions at our institution was determined. Sixty-three consecutive patients with an obstetrical brachial plexus palsy who had had both preoperative CT myelography and reconstructive surgery were selected. All CT myelograms were analyzed post hoc by a single neuroradiologist in a manner blind to the surgical findings. At each root level of the brachial plexus, the presence of a pseudomeningocele was noted along with the presence or absence of rootlets within each identified pseudomeningocele. Extraforaminal root avulsions later determined at surgery were reviewed by a single surgeon in a manner blind to the radiographic results. Surgical and radiographic findings were then compared at each corresponding root level. A total of 281 roots were examined. The sensitivity, specificity, positive predictive value, and likelihood ratio for root avulsions with pseudomeningoceles were 0.63, 0.85, 0.40, and 4.2, respectively. For pseudomeningoceles for which rootlets traversing the sac could not be identified, these values were 0.37, 0.98, 0.74, and 18.5, respectively. The presence of pseudomeningoceles with or without rootlets was not a sensitive indicator of root avulsions. Root avulsions were better predicted by identifying the absence of rootlets in a pseudomeningocele. This absence on CT myelography may be used to suggest an extraforaminal root avulsion due to its high specificity and high likelihood ratio.     

Dorsal root entry zone lesions in the treatment of pain following brachial plexus avulsion, spinal cord injury and herpes zoster

This paper details the long-term results in patients treated with dorsal root entry zone (DREZ) lesions for the treatment of pain following brachial plexus avulsion, spinal cord injury, and herpes zoster. With our current operative technique, 82% of patients with brachial plexus avulsion injuries were afforded long-term pain relief. Patients with pain confined to dermatomes just below the level of spinal injury also did well with DREZ lesions, although the results were less good in patients with diffuse pain or with sacral pain. The postoperative results in patients with postherpetic pain were disappointing.     

The surgical treatment of brachial plexus injuries in adults

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Evaluate clinically a patient with brachial plexus paralysis and define the appropriate electrophysiologic and radiographic studies. 2. Differentiate between preganglionic (root) avulsion and postganglionic lesions and identify appropriate motor donors and nerve grafts. 3. Describe various nerve reconstructive strategies and make appropriate selection of secondary procedures for shoulder stability, elbow flexion, and hand reanimation. 4. Anticipate the possible functional outcome.     

Activation of phospholipase-Cγ and protein kinase C signal pathways helps the survival of spinal motoneurons injured by root avulsion

The signaling transduction processes involved in avulsion-induced motoneuron (MN) death have not been elucidated. Using the brachial plexus root avulsion rat model, we showed that avulsion-activated phosphorylation of phospholipase-Cγ (PLCγ) and protein kinase C (PKC) occurred in injured spinal MNs within 72?h of injury. Moreover, some MNs positive for PLCγ and PKC are also positive for avulsion-induced neuronal nitric oxide synthase (nNOS). Inhibition of PLCγ/PKC signal pathway, either with PLCγ inhibitor, 1-[6-((17β-3-methoxyestra-1,3,5(10)-trien-17-yl) amino)hexyl]-1H-pyrrole-2,5-dione, or with PLCγ siRNA augmented avulsion-induced MN death. 1-[6-((17β-3-methoxyestra-1,3,5(10)-trien-17-yl) amino)hexyl]-1H-pyrrole-2,5-dione also inhibited PKC phosphorylation and exacerbated avulsion-induced reductions in the nNOS protein level in injured spinal segments. Moreover, activation of PLCγ/PKC signal pathway with PKC activator, phorbol-12-myristate-13-acetate, decreased avulsion-induced MN death. The temporal profile of PLCγ/PKC signaling appears to be crucial for the survival of spinal MNs after root avulsion. Our data suggest that PLCγ mediates, while PKC and nNOS are associated with, the avulsion-induced MN death in brachial plexus root avulsion.     

l-Theanine and NEP1-40 promote nerve regeneration and functional recovery after brachial plexus root avulsion

Brachial plexus root avulsion causes severe sequelae Treatments and prognosis face many problems, including inflammatory reaction, oxidative damage, and myelin related inhibitory effect. l-Theanine has anti-inflammatory, anti-oxidative, and neuroprotective effects. NEP1-40 competitively inhibits Nogo-66 receptor (NgR1) promotes axonal regeneration. Forty-eight Sprague-Dawley rats were randomly assigned into four groups to establish an animal model of brachial plexus root avulsion. Inflammation and oxidative damage were evaluated by spectrophotometry and motor function of the upper limbs was assessed via Terzis grooming test after modeling. Immunofluorescence and hematoxylin and eosin staining were utilized to determine the content of reactive oxygen species, activation of microglial cells, neuroprotection, and nerve regeneration. Compared with the control group, the L-Theanine + NEP1-40 group had significantly decreased myeloperoxidase, malondialdehyde, interleukin-6, reactive oxygen species, and microglial cells, significantly increased score on the Terzis grooming test, increased motor neuron content, and thickened muscle fibers, increased area, and appearance of large and clear motor endplate structures. The results of this study suggest that l-Theanine combined with NEP1-40significantly promoted nerve regeneration after brachial plexus root avulsion, and may be a potential treatment for promoting nerve regeneration. Possible mechanisms underlying these results are alleviation of oxidative damage and inflammatory responses in the injured area and antagonism of myelin inhibition.     

Local Riluzole Release from a Thermosensitive Hydrogel Rescues Injured Motoneurons through Nerve Root Stumps in a Brachial Plexus Injury Rat Model

Neurochemical Research - The C5-C6 nerve roots are usually spared from avulsion after brachial plexus injury (BPI) and can thus be used as donors for nerve repair. A BPI rat model with C5-C6 nerve...     

Pain control with laser-produced dorsal root entry zone lesions

Pain relief was evaluated in 40 patients with various types of deafferentation pain that were treated with dorsal root entry zone (DREZ) lesions produced with microsurgical lasers. Good long-term pain relief was evident in some paraplegics and in all patients with brachial plexus avulsion. Several other small subgroups of patients benefited from laser DREZ lesions as well. Pain associated with arachnoiditis and peripheral nerve injury or neuropathy did not respond to laser DREZ lesioning. Based upon the smaller lesion dimensions produced with the lasers, it is proposed that interruption of impulses in the tract of Lissauer may be a mechanism of pain control in patients that responded to laser DREZ lesions.     

Neurosurgical technique of the dorsal root entry zone operation

The dorsal root entry zone operation was introduced in 1976 to relieve the pain of brachial plexus avulsion. Since then it has been applied to pain treatment in paraplegia, postherpetic pain, phantom limb pain and other types of of deafferentation pain. Over 400 operations have been done at the Duke University Medical Center with overall good results in 60% of pain patients.     

Contralateral C7 nerve transfer - Our experiences over past 25 years

ABSTRACT: Contralateral C7 nerve transfer has been used in treating brachial plexus avulsion injury since 1986. During the past two and half decades, much has been achieved, yet more needs to be explored. In this review article, the indications, technical details, outcome and pitfalls of this technique are summarized.     

The Hopkins experience with lesions of the dorsal horn (Nashold's operation) for pain from avulsion of the brachial plexus

Lesions of the dorsal horn (DREZ operation) have been reported to be useful in reducing pain secondary to avulsion of the brachial plexus. Ten patients had the DREZ operation for this condition at The Johns Hopkins Hospital by one of us (JNC) between 1981 and 1985. Radiofrequency heat lesions were made. The patients were interviewed 7-52 months after the operation by one of two individuals not involved in the procedure to assess pain relief and postoperative complications. The mean pain relief was 85%, and there were no significant complications. It is concluded that the DREZ operation is the treatment of choice for treatment of severe pain that results from avulsion of the brachial plexus.     

Lesions of spinal and trigeminal dorsal root entry zone for deafferentation pain. Experience of 35 cases

Spinal and trigeminal dorsal root entry zone destruction (DREZ-tomy) was performed on 35 patients with deafferentation pain of various types. Overall, satisfactory pain relief was obtained in 65.5% of spinal DREZ-tomy cases in the follow-up observation. The result in the brachial plexus avulsion group was the best (82.4% improved), followed by the limb pain group without root avulsion (50.0%), but the truncal or visceral pain group showed the worst result (33.3%). Two patients with postherpetic trigeminal neuralgia were completely relieved of pain in the average follow-up period of 32 months, while in 2 patients with postrhizotomy facial pain, pain recurred 4 months after the operation in 1, and, in the other, pain in the medial part of the face remained unchanged. Complications were seen in about 60% of the patients, which were, however, all mild, except for 2 cases of death due to gastrointestinal disease.     

Evaluation of Avulsion-Induced Neuropathology in Rat Spinal Cords with 18F-FDG Micro-PET/CT

Brachial plexus root avulsion (BPRA) leads to dramatic motoneuron death and glial reactions in the corresponding spinal segments at the late stage of injury. To protect spinal motoneurons, assessment of the affected spinal segments should be done at an earlier stage of the injury. In this study, we employed ¹⁸F-FDG small-animal PET/CT to assess the severity of BPRA-induced cervical spinal cord injuries. Adult Sprague-Dawley rats were randomly treated and divided into three groups: Av+NS (brachial plexus root avulsion (Av) treated with normal saline), Av+GM1 (treated with monosialoganglioside), and control. At time points of 3 day (d), 1 week (w), 2 w, 4 w and 8 w post-injury, ¹⁸F-FDG micro-PET/CT scans and neuropathology assessments of the injured spinal roots, as well as the spinal cord, were performed. The outcomes of the different treatments were compared. The results showed that BPRA induced local bleeding and typical Wallerian degeneration of the avulsed roots accompanied by ¹⁸F-FDG accumulations at the ipsilateral cervical intervertebral foramen. BPRA-induced astrocyte reactions and overexpression of neuronal nitric oxide synthase in the motoneurons correlated with higher ¹⁸F-FDG uptake in the ipsilateral cervical spinal cord during the first 2 w post-injury. The GM1 treatment reduced BPRA-induced astrocyte reactions and inhibited the de novo nNOS expressions in spinal motoneurons. The GM1 treatment also protected spinal motoneurons from avulsion within the first 4 w post-injury. The data from this study suggest that ¹⁸F-FDG PET/CT could be used to assess the severity of BPRA-induced primary and secondary injuries in the spinal cord. Furthermore, GM1 is an effective drug for reducing primary and secondary spinal cord injuries following BPRA.     

Brachial plexus injury.

A 28-year-old man shot himself in the left posterior triangle of the neck with a shotgun. At the initial operation secondary repair of the resultant brachial plexus injury was decided upon in view of the difficulty in assessing lesions in continuity at this point after injury. The patient had total brachial plexus palsy. Nine weeks after the injury sensory and motor function were returning and the only element of the brachial plexus not showing evidence of nerve fibre continuity was the musculocutaneous nerve. Sural nerve autografts were sutured between the trimmed proximal and distal stumps of this nerve. By 4 months after the injury there was further improvement in both sensory and motor function, and by 18 months there was sensation in the autonomous zones of both median and ulnar nerves and good return of muscle power.     

三通道电刺激仪的研制及对臂丛神经损伤的临床疗效

目的:研制可用于臂丛神经损伤治疗的三通道电刺激仪,并且将之应用于临床臂丛神经损伤患者,观察该仪器治疗臂丛神经损伤的临床效果。方法:由主控模块、显示模块、键盘模块、三个通道的电刺激发生器模块以及电源模块组成系统,可以连续交替释放脉冲刺激,针对不同神经和肌肉,选择不同的刺激位点。将60例臂丛神经损伤术后的患者随机分成试验组(30例)和对照组(30例),试验组术后第三周使用三通道电刺激仪治疗,对照组不做处理,患者术后随访6-12月后,观察患者上肢肩部、肘部功能恢复情况。结果:试验组治疗后上臂丛、全臂丛、下臂丛的肩部、肘部功能均好于治疗前,差异明显,均有统计学意义(P0.05);试验组上臂丛、全臂丛、下臂丛的肩部、肘部治疗效果均显著优于对照组,差异有统计学意义(P0.05)。结论:三通道电刺激仪可以有效地促进臂丛神经损伤后上肢功能的康复,可以对三组神经和肌肉交替进行电刺激,使用方便,并且便于携带,患者较为满意。     

Genetic mapping to 10q23.3-q24.2, in a large Italian pedigree, of a new syndrome showing bilateral cataracts, gastroesophageal reflux, and spastic paraparesis with amyotrophy.

We have recently observed a large pedigree with a new rare autosomal dominant spastic paraparesis. In three subsequent generations, 13 affected individuals presented with bilateral cataracts, gastroesophageal reflux with persistent vomiting, and spastic paraparesis with amyotrophy. Bilateral cataracts occurred in all affected individuals, with the exception of one patient who presented with a chorioretinal dystrophy, whereas clinical signs of spastic paraparesis showed a variable expressivity. Using a genomewide mapping approach, we mapped the disorder to the long arm of chromosome 10 on band q23.3-q24.2, in a 12-cM chromosomal region where additional neurologic disorders have been localized. The spectrum of phenotypic manifestations in this family is reminiscent of a smaller pedigree, reported recently, confirming the possibility of a new syndrome. Finally, the anticipation of symptoms suggests that an unstable trinucleotide repeat may be responsible for the condition.     

Degeneration of primary afferent terminals following brachial plexus extensive avulsion injury in rats

Important breakthroughs in the understanding regeneration failure in an injured CNS have been made by studies of primary afferent neurons. Dorsal rhizotomy has provided an experimental model of brachial plexus (BP) avulsion. This is an injury in which the central branches of primary afferents are disrupted at their point of entry into the spinal cord, bringing motor and sensory dysfunction to the upper limbs. In the present work, the central axonal organization of primary afferents was examined in control (without lesion) adult Wistar rats and in rats subjected to a C3-T3 rhizotomy. Specific sensory axon subtypes were recognized by application of antibodies to the calcitonin gene-related peptide (CGRP), the P2X3 purinoreceptor, the low-affinity p75-neurotrophin receptor and the retrograde tracer cholera toxin subunit beta (TCbeta). Other subtypes weres labeled with the lectin Griffonia simplicifolia 1B4. Using immunohistochemistry and high resolution light microscopy, brachial plexus rhizotomy in adult rats has proven a reliable model for several neural deficits in humans. This lesion produced different degrees of terminal degeneration in the several types of primary afferents which define sub-populations of sensitive neurons. Between the C6 and C8 levels of the spinal cord,, deafferentation was partial for peptidergic GCRP-positive fibers, in contrast with elimination of non peptidergic and myelinated fibers. Dorsal rhizotomy has provided an adequate experimental model to study sensory alterations such as acute pain and allodynia as well as factors that affect regeneration into the CNS., Therefore, the differential deafferentation response must be considered inr the evaluation of therapies for nociception (pain) and regeneration for brachial plexus avulsion. The anatomical diffierences among the primary afferent subtypes also affect their roles in normal and damaged conditions.     

Functional Motor Recovery from Motoneuron Axotomy Is Compromised in Mice with Defective Corticospinal Projections

Brachial plexus injury (BPI) and experimental spinal root avulsion result in loss of motor function in the affected segments. After root avulsion, significant motoneuron function is restored by re-implantation of the avulsed root. How much this functional recovery depends on corticospinal inputs is not known. Here, we studied that question using Celsr3|Emx1 mice, in which the corticospinal tract (CST) is genetically absent. In adult mice, we tore off right C5–C7 motor and sensory roots and re-implanted the right C6 roots. Behavioral studies showed impaired recovery of elbow flexion in Celsr3|Emx1 mice compared to controls. Five months after surgery, a reduced number of small axons, and higher G-ratio of inner to outer diameter of myelin sheaths were observed in mutant versus control mice. At early stages post-surgery, mutant mice displayed lower expression of GAP-43 in spinal cord and of myelin basic protein (MBP) in peripheral nerves than control animals. After five months, mutant animals had atrophy of the right biceps brachii, with less newly formed neuromuscular junctions (NMJs) and reduced peak-to-peak amplitudes in electromyogram (EMG), than controls. However, quite unexpectedly, a higher motoneuron survival rate was found in mutant than in control mice. Thus, following root avulsion/re-implantation, the absence of the CST is probably an important reason to hamper axonal regeneration and remyelination, as well as target re-innervation and formation of new NMJ, resulting in lower functional recovery, while fostering motoneuron survival. These results indicate that manipulation of corticospinal transmission may help improve functional recovery following BPI.     

Macrophages and dendritic cells in the rat meninges and choroid plexus: three-dimensional localisation by environmental scanning electron microscopy and confocal microscopy

The present investigation provides novel information on the topographical distribution of macrophages and dendritic cells (DCs) in normal meninges and choroid plexus of the rat central nervous system (CNS). Whole-mounts of meninges and choroid plexus of Lewis rats were incubated with various anti-leucocyte monoclonal antibodies and either visualised with gold-conjugated secondary antibody followed by silver enhancement and subsequent examination by environmental scanning electron microscopy or by the use of fluorochromes and confocal microscopy. Large numbers of MHC class II⁺ putative DCs were identified on the internal or subarachnoid aspect of dural whole-mounts, on the surface of the cortex (pia/arachnoid) and on the surface of the choroid plexus. Occupation of these sites would allow DCs access to cerebrospinal fluid (CSF) and therefore allow antigens into the subarachnoid space and ventricles. By contrast, macrophages were less evident at sites exposed to CSF and were more frequently located within the connective tissue of the dura/arachnoid and choroid plexus stroma and also in a sub-pial location. The present data suggest that DC may be strategically located within the CNS to sample CSF-borne antigens. Furthermore, the data suggest that CNS tissue samples collected without careful removal of the meninges may inadvertantly be contaminated by DCs and meningeal macrophages.     

Giant choroid plexus cyst as an accidental finding in an older man

Choroid plexus cysts (CPC) are usually found at the end of the second trimester of pregnancy. Sometimes they can be accidentally and found on prenatal ultrasound examinations. Vast majority of CPC resolve spontaneously by 28th weeks gestation. In the older aged group the choroid plexus cysts are extremely rare pathomorphologic medical entity. Since they are almost always asymptomatic, they are therefore accidentally found on brain magnetic resonance (MR) or computed tomography (CT) scans. They are usually located in the lateral ventricles and measure around 2 cm in diameter. We present a case of a 75-year-old male with a giant choroid plexus cyst whose leading symptom was excruciating headache refractory to previous conservative therapy. He underwent surgery when osteoplastic craniotomy was performed with cyst fenestration and ablation. His recovery was uneventful with total regression of headaches. Reviewing the recent literature we did not find such a case considering the patients age and the size of the choroid plexus cyst.