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.     

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.     

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.     

Successful treatment of phantom pain with dorsal root entry zone coagulation

We studied 22 patients with amputation due to trauma, gangrene, or cancer. All developed postamputation pain, underwent a dorsal root entry zone (DREZ) procedure, and were followed from 6 months to 4 years after surgery. Overall, only 8 (36%) of these 22 patients had pain relief. However, good results were obtained in 6 (67%) of 9 patients with phantom pain alone, and in 5 (83%) of 6 patients with traumatic amputations associated with root avulsion. Poor results were obtained in patients with both phantom and stump pain, or stump pain alone. The DREZ procedure has a well-defined, but limited role in the treatment of postamputation pain.     

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.     

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.     

Remote Paraparesis due to a Traumatic Extradural Arachnoid Cyst Developing 2 Years after Brachial Plexus Root Avulsion Injury: Case Report and Review of the Literature

Traumatic extradural arachnoid cyst is a rare entity. However, late appearance of paraparesis due to formation of an extradural arachnoid cyst as a sequel of brachial plexus injury is extremely rare and the literature regarding this issue is scarce revealing only 11 cases. Herein, we report a patient with delayed progressive spastic paraparesis appearing after a multilevel brachial plexus root avulsion injury where imaging revealed formation of a large traumatic extradural arachnoid cyst at the cervicothoracic region. Furthermore, to propose that a high-energy trauma might simultaneously result in delayed formation of an extradural arachnoid cyst. However, preganglionic root avulsion injury with pseudomeningocele formation in association with extradural arachnoid cyst is not reported previously. A case of a 36-year-old man with spastic paraparesis developing 2 years after a multilevel brachial plexus root avulsion injury is presented. Root avulsion had immediately resulted in complete paralysis of the left upper limb that had not ameliorated. Imaging studies of the cervicothoracic region disclosed left-sided multilevel pseudomeningoceles and a large extradural arachnoid cyst extending from C5 to T2. After appropriate en bloc laminotomy, the cyst was excised and the causative dural tear was closed. Subsequently, three large defects of pseudomeningoceles were obliterated with artificial dural patch for the prevention of cord herniation. This was followed with laminoplasty of the corresponding levels after dural closure. The postoperative course was uneventful and paraparesis recovered steadily within 2 months. Paraparesis even years after brachial plexus injury should be regarded as a serious event that deserves extensive imaging survey for the possibility of the formation of an extradural arachnoid cyst. Careful review of the literature disclosed that the current case is the 12th case that an extradural arachnoid cyst has developed after brachial plexus injury and the first example that the pathogenic factor that might be implicated in occurrence of this rare association could be clarified with review of the MRI features. Actually, the presence of posttraumatic pseudomeningoceles in association with an arachnoid cyst in the current case is in favor of the belief that only preganglionic root injuries that are in close proximity to the spinal canal had been the cause dural tear with remote formation of extradural arachnoid cyst.     

B超声引导下肋锁间隙与喙突入路连续臂丛神经阻滞对Barton骨折术后镇痛效果比较

目的:比较超声引导下肋锁间隙与喙突两种入路连续臂丛神经阻滞对Barton骨折手术患者术后的镇痛效果。方法:选择择期行Barton骨折手术患者60例,随机分为肋锁间隙入路连续臂丛神经阻滞组(A组,n=30)和喙突入路连续锁骨下臂丛神经阻滞组(B组,n=30)。两组均在超声引导下进行臂丛神经阻滞,同时留置神经阻滞导管,麻醉后2小时经神经阻滞导管连接无线电子镇痛泵。记录手术过程中神经深度、麻醉操作时间,并评估麻醉效果;记录术后第一次追加药物时间;记录麻醉后6 h、12 h、18 h、24 h、36 h、48 h静息及运动状态VAS评分;记录术后第一天和第二天镇痛泵有效按压次数及补救镇痛情况;记录患者满意度及并发症发生情况。结果:与B组相比,A组神经深度明显减浅(P<0.05),麻醉操作时间显著缩短(P<0.05),术后第一次追加药物时间延长(P<0.05),麻醉后12 h、18 h、24 h、36 h静息及运动状态VAS评分较低(P<0.05),术后第一天有效按压次数明显减少(P<0.05),患者满意度评分高(P<0.05),误穿血管发生率明显减少(P<0.05)。结论:超声引导下肋锁间隙入路与喙突入路连续锁骨下臂丛神经阻滞均可安全有效用于Barton骨折手术术后镇痛;但肋锁间隙连续臂丛神经阻滞术后镇痛效果更好,且具有神经阻滞深度浅、操作时间更短、阻滞效果更好、患者满意度更高及并发症更少等优点。     

Experimental anatomical considerations of the dorsal root entry zone lesions for pain relief

Dorsal root entry zone (DREZ) lesions were made in the cervical dorsal horn in cat and monkey. Terminal degeneration was observed in the lateral cervical nucleus in cat and contralateral VPL in monkey by Fink-Heimer stain. WGA-HRP was injected in the cervical dorsal horn of cat and retrograde labelled cells were observed mainly in the raphe nucleus, parabrachial nucleus, locus coeruleus, K?lliker-Fuse nucleus, Eddinger-Westphal nucleus, and hypothalamic area, indicating that these descending fiber systems are involved by the DREZ lesion. The functional role of these fibers in regard to deafferentation pain relief seems now to be open to discussion.     

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。     

经肱动脉途径冠状动脉介入治疗并发症的预防及处理

目的:评价130例次经肱动脉途径冠状动脉介入治疗(PCI术)局部并发症情况.方法:连续入选2009年3月至2011年12月我院经肱动脉途径冠状动脉PCI术的病例130例次.分析经肱动脉介入治疗操作并发症情况.结果:共24例患者发生了局部并发症,并发症发生率为18.5％.其中穿刺局部发生血肿22例(16.9％),其中1例合并骨筋膜室综合征及正中神经损伤(0.8％),局部神经损伤1例(0.8％),假性动脉瘤1例(0.8％).经处理后血肿全部吸收,最后仍有1例正中神经损伤和1例假性动脉瘤未能完全康复.结论:经肱动脉途径冠状动脉PCI术并发症发生率较高,熟悉肱动脉穿刺方法、掌握标准的压迫止血包扎方案、术后肢体夹板制动、并对其并发症有足够的认识和处理对策的充分准备可以减少并发症及其不良后果的发生.     

臂丛神经撕脱伤后慢性疼痛患者脑区葡萄糖代谢的研究

臂丛神经撕脱伤后慢性疼痛是一种临床上顽固性神经病理性疼痛.然而,对于其潜在的中枢机制还知之甚少.为了进一步探讨臂丛神经撕脱伤后慢性疼痛的相关脑区活动,利用18F-脱氧葡萄糖(FDG)正电子断层扫描(PET)技术观察臂丛神经撕脱后慢性疼痛患者的脑葡萄糖代谢.选择左侧臂丛神经撕脱伤后慢性疼痛行脊髓后根入髓区(DREZ)切开术后疼痛减轻>75%的患者,共5例,分别在术前和术后14天行PET扫描采集数据,同时行视觉模拟评分(VAS),汉密尔顿(Hamilton)抑郁和焦虑评分.用统计参数图(SPM2)软件分析数据.与术前疼痛状态下相比,术后葡萄糖代谢明显减低的脑区有双侧尾状核,眶额回(OFC)(BA11),对侧扣带下回(BA25)和同侧前额叶背外侧区域(DLPFC)(BA46/47).葡萄糖代谢明显增高的脑区有对侧丘脑,枕核和同侧项叶(BA7).研究结果提示,涉及情绪、注意和疼痛内在调节的脑区在臂丛神经撕脱伤后慢性疼痛的调制中发挥重要作用.     

Validity of median nerve somatosensory evoked potentials in the diagnosis of supraclavicular brachial plexus lesions

Experience with median nerve SEPs in the diagnosis of brachial plexus lesions is analysed in 49 patients selected from a total material of 264 cases with brachial plexus problems tested by SEP techniques. Median nerve SEPs were always compared with the results of SEPs after stimulation of at least one other nerve relevant to the site of the lesion as suspected clinically and electromyographically. All patients presented with unilateral brachial plexus problems and all root lesions were verified by clinical presentation, EMG studies, myelogram or surgery. There were 19 brachial plexus injuries, 13 cases with cervical spondylopathic rediculopaties without myelopathy and 7 patients presented brachial plexopathy with systemic cancer. It was found that median nerve SEPs were always normal in injuries of upper trunk and root avulsions confined to one or two root levels. Median nerve SEPs were abnormal in multiple trunk lesions and multiple root avulsions. In patients with spondylopathic radiculopathies median nerve SEPs were normal apart from one case where involvement of multiple roots was present. Median nerve SEPs were useful in assessing patients presenting brachial plexus problems in the presence of systematic cancer apart from cases where lower trunk involvement was present.In general, median nerve SEPs are useful if they are combined with SEP testing of other nerves anatomically more closely related to the problem as outlined clinically and electromyographically.     

Full-length phrenic nerve transfer by means of video-assisted thoracic surgery in treating brachial plexus avulsion injury

Phrenic nerve transfer has been widely used in treating brachial plexus avulsion injury. However, the present method crosses the thoracic part of the phrenic nerve, and nerve graft is needed, resulting in a long period of regeneration and partly irreversible muscle atrophy. We present our early experience of using video-assisted thoracic surgery to harvest a full length of phrenic nerve for transfer. Fifteen patients (mean age, 28 years) were treated. The thoracic part of the phrenic nerve was freed by means of video-assisted thoracic surgery and taken out of the thoracic cavity, and a full-length phrenic nerve was transferred to the musculocutaneous nerve to recover elbow flexion. The patients were followed. Another 29 patients with long-term follow-up who underwent traditional cervical phrenic nerve to musculocutaneous nerve transfer in our institute between 1994 and 1997 were selected. The period of newborn potential appearing in the biceps and the period for biceps to achieve M3 between two groups were compared. The operation was safe and no complications occurred. The additional length of phrenic nerve was 12.3 +/- 4.5 cm. Eleven patients received sufficient follow-up. Eight patients achieved biceps recovery to M3 (elbow flexion against gravity), and mean time was 198.8 +/- 36.0 days, much earlier than that of the traditional method (p < 0.01). Pulmonary function recovered to the preoperative level 9 months after operation. This new method is safe and minimally invasive. The result of full-length phrenic nerve transfer is much better than that of the traditional method. It obviously shortens the time required for nerve reinnervation, and offers a promising method for patients who have had a long interval from injury to operation and for forearm muscle reconstruction by phrenic nerve transferred to the median nerve or combined with free-muscle transfer.     

Treatment of diabetic neuropathy by decompression of the posterior tibial nerve

A series of 58 operations on 36 patients were performed for decompression of the posterior tibial nerve for the treatment of diabetic neuropathy. Preoperative symptoms included lack of sensation, pain, or both. Eleven of the 36 patients had neurotrophic ulcers, which were treated simultaneously. The operation was found to be effective for relief of pain in 24 of the 28 patients with that complaint (86 percent). Restoration of sensation was less consistent with improvement noted in 18 of the 36 patients (50 percent). The follow-up period ranged from 12 to 84 months (mean, 32 months) and five patients had some degree of recurrent symptoms. No patient has developed a new ulcer after nerve decompression. Wound complications were minimal (12 percent), even though ulcers were treated simultaneously. No patient required surgical treatment for the decompression incision, although one did require hospital admission for treatment of a wound infection. In general, the procedure seemed to be a worthwhile treatment, which should be considered ill selected diabetics with symptomatic neuropathy.     

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.     

Efficacy of intervention strategies in a brachial plexus global avulsion model in the rat

The treatment of brachial plexus avulsion lesions invariably involves the use of neurotization procedures. Although some of these therapeutic strategies have been used for the past 20 years to restore selective function to the injured extremity, the individual efficacy of these nerve transfers has not been measured objectively, thereby rendering the prognostication of outcomes for these techniques a major problem. Using a true global avulsion model, the present study compares outcomes of the various neurotization procedures for the first time. The strength of this experimental model is that each nerve transfer tested leads to a common terminal pathway involving a single target-namely, the biceps muscle. Thus, quantitative measurements of biceps restoration will provide strong clues to the power of axonal regrowth of that particular motor pool. This study also introduces the Terzis grooming test, a modified behavioral test that can be quantified and that can provide an overall functional scale in the assessment of outcome. Thirty-five Sprague-Dawley rats were divided into seven groups, with each group testing a different motor donor for biceps reinnervation. The ipsilateral brachial plexus was globally avulsed in all animals, with the exception of the ipsilateral C7 group, and the respective motor donor coapted in an end-to-end fashion to the musculocutaneous nerve. Functional outcomes were measured by the Terzis grooming test, electromyography, biceps muscle force measurements, motor end plate counts, and quantitative axonal morphometry. The values of the different parameters were expressed as a standard score on a common scale. The relative standings of each group on each parameter were compared. Superior outcome was observed in the phrenic, the hypoglossal, and the ipsilateral C7 groups.     

Complications of microsurgical reconstruction of obstetrical brachial plexus palsy

The charts of the 173 consecutive patients who underwent microsurgical reconstruction for obstetrical brachial plexus palsy from 1988 to 1999 (inclusive) in the Division of Plastic Surgery at the Hospital for Sick Children were analyzed. The overall complication rate was 33.5 percent, and there was no mortality in this series. The most significant intraoperative complication was accidental extubation, which occurred five times in the first 84 patients (6 percent of this early group; 2.9 percent of the whole series). This complication was addressed by suturing the endotracheal tube to the membranous septum and by using a transparent drape to allow direct visualization of the tube in all 89 subsequent patients. There have been no further accidental extubations. Postoperative fluid overload occurred in 14 patients (8.1 percent), three (1.7 percent) of whom developed pulmonary edema. Intensive care unit admission was required in two of those patients. Diuretic treatment was required in seven patients. No patient receiving less than or equal to 4 ml/kg/hour developed fluid overload, whereas 50 percent of the patients receiving greater than or equal to 10 ml/kg/hour did. Currently, the authors' policy is to strictly limit intravenous maintenance fluids to 4 ml/kg/hour or less. Despite the long and complex procedure required to reconstruct obstetrical brachial plexus palsy, the incidence of significant complications can be minimized with simple precautions, such as suturing the endotracheal tube to the septum or reducing the amount of fluids administered during the operation.     

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.     

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...