Morphological anatomy of thoracolumbar nerve roots and dorsal root ganglia

The aim of this study is to ascertain the anatomic parameters of the spinal roots and dorsal root ganglia and to demonstrate their clinical significance. Samples from 24 adult autopsy subjects were obtained from roots and dorsal root ganglia at levels L1 through L5. The anatomic parameters of epidural nerve roots: the distance between the epidural nerve roots and the proximal edge of the dorsal root ganglia and the average diameter of the nerve root gradually, increased from L1 to L5. The midline nerve root angle gradually decreased from L1 to L5. The anatomic parameters of subarachnoid nerve roots: the length of subarachnoid nerve roots and both the ventral and dorsal roots’ diameter, increased from L1 to L5. The number of ventral and dorsal rootlets per nerve root ranged from one to three. The anatomic parameters of dorsal root ganglia: the length and width of the thoracic and lumbar dorsal root ganglia, gradually increased from L1 to L5. The locations of the dorsal root ganglia were recorded as the intraspinal, intraforaminal and extraforaminal using some bony landmarks. Most dorsal root ganglia located intraforaminally, and the extraforaminal type is more common in the L5 root than other thoracic and lumbar roots, regardless of age. This knowledge is a must not only to avoid complications but also for the success, safety and effectiveness of microsurgical operations.     

Spinal glial activation and cytokine expression after lumbar root injury in the rat

STUDY DESIGN: This study was designed to examine the behaviorial immunohistochemical changes of spinal glial cells and spinal Interleukin (IL)-1beta expression after various nerve root injuries used as models of lumbar radiculopathy. OBJECTIVES: In order to better understand the role of central inflammation in the pathophysiologic mechanisms that give rise to pain associated with lumbar radiculopathy, this research studied the relationship between pain-related behavior associated with spinal glial activation and IL-1beta expression generated by three types of nerve root injury: loose ligation with chromic gut, loose ligation with silk, and tight ligation with silk. SUMMARY OF BACKGROUND DATA: An animal model of lumbar radiculopathy originally described by Kawakami and Weinstein involved loose ligation of unilateral L4-L6 nerve roots with chromic gut. Characterization and establishment of such an animal model of low back pain enables further investigation of the nature of the pathophysiologic mechanisms associated with lumbar radiculopathy in humans. METHODS: Seventy-three rats were divided into four treatment groups. Chromic group (n = 25): The L5 nerve roots (dorsal and ventral) were exposed by hemilaminectomy and loosely ligated with chromic gut. Tight silk group (n = 18): The exposed L5 nerve roots were tightly ligated extradurally with 5-0 silk suture. Loose silk group (n = 15): two loose ligatures of 5-0 silk were placed around the exposed L5 nerve roots. Sham group (n = 15): the rats were subjected to laminectomy alone for exposing nerve roots. Following surgery, thermal hyperalgesia and mechanical allodynia was assessed time-dependently up to 42 days post operatively. At 1, 3, 7, 14, and 42 days postoperatively, the rats in each group were perfused with fixative. The L5 spinal cord segments was harvested and cryosectioned for glial and cytokine immunohistochemistry. RESULTS: In the chromic and the tight silk group, an immediate and sustained mechanical allodynia was observed in the ipsilateral hind paw up to 35 days postoperatively. The loose silk group also showed an immediate mechanical allodynia that subsided by 14 days postoperatively. Sham-treated animals exhibited mild mechanicalallodynia for the initial 7 days after the surgery. Thermalhyperalgesia was evident in the three primary treatment groups, but not in the sham-treated rats. OX-42 expression was elevated in the gray matter of the L5 spinal section by 3 days in the chromic, the tight silk, and the loose silk groups as compared to the sham group. Astrocytic activation increased over time in all groups except the sham group. There was no direct correlation between degree of microglial response and severity of pain behaviors. In contrast, astrocytic activation demonstrated a direct relationship with the elevation of mechanical allodynia for the first 7 days. In addition, spinal IL-1beta protein expression was increased bilaterally in the superficial layer of the dorsal horn and cell nuclei of the ventral horns in the ligature treated groups as compared with the sham group. CONCLUSION: Direct mechanical and/or chemical injury to lumbar roots in the rat gives rise to pain behavior suggestive of lumbar radiculopathy. The finding that glial activation and enhanced IL-1beta expression are observed in the spinal cord after root injury supports a central, neuroimmune component in the generation of lumbar radiculopathy. A further understanding of the immunologic consequences of root injury may lead to further development and the novel use of selective cytokine-inflammatory inhibitors for the treatment of low back pain associated with radiculopathy.     

Clinical features of extraforaminal lumbar disc herniation based on the radiographic location of the dorsal root ganglion

STUDY DESIGN: The relations between the location of the dorsal root ganglion and pre- and postoperative symptoms were reviewed retrospectively in 27 patients who underwent radiculography and posterior discectomy. OBJECTIVES: To evaluate the clinical features and surgical outcome of extraforaminal lumbar disc herniation based on the location of dorsal root ganglion. SUMMARY OF BACKGROUND DATA: The location of dorsal root ganglia has been reported to be correlated with a variety of radicular symptoms. Extraforaminal lumbar disc herniation has several specific clinical features, one of which is severe radicular pain. However, there is no report in the literature on the association between the location of the dorsal root ganglia and the severity of the symptoms of extraforaminal lumbar disc herniation. METHODS: The radiographic location of the dorsal root ganglion of each compressed nerve root was determined by preoperative direct radiculograms. All patients were classified into the following three groups according to the location of dorsal root ganglion: intraspinal, intraforaminal, and extraforaminal. The incidences of these locations were 5 of 27 (18.5%), 15 of 27 (55.5%), and 7 of 27 (25.9%), respectively. The relation between the location of the dorsal root ganglion and clinical parameters such as the level of the compressed nerve root, the degree of limitation on straight leg raising test, the severity of the pre- and postoperative subjective symptoms (leg pain, low back pain, and walking capacity), clinical signs (sensory and motor disturbance), and the recovery rate were investigated. RESULTS: The degree of limitation on the straight leg raising test in the extraforaminal group tended to be low, compared with that in the intraspinal and intraforaminal groups. Low back pain in the extraforaminal group was more severe than that in the intraspinal and intraforaminal groups. Preoperative leg pain in the extraforaminal group was significantly more severe that that in the intraspinal group, and the walking capacity in the extraforaminal group tended to be lower than that in the intraspinal and intraforaminal groups. No significant differences were found between the location of dorsal root ganglion and the preoperative sensory or motor disturbance and surgical outcomes. CONCLUSION: The location of the dorsal root ganglion might influence the severity of radicular symptoms (pain and walking distance tolerance) in patients with extraforaminal lumbar disc herniation.     

Sensory innervation of the dorsal portion of the lumbar intervertebral disc in rats

STUDY DESIGN: The vertebral levels of dorsal root ganglia innervating the dorsal portion of the L5-L6 intervertebral disc were investigated in rats using a retrograde transport method. The pathways and functions of nerve fibers supplying the dorsal portion of the disc were determined by denervation and immunohistochemistry. OBJECTIVES: The dorsal portion of the lumbar intervertebral disc has been reported to be innervated segmentally, but anesthetic block of the paravertebral sympathetic trunks and the L2 spinal nerve can relieve discogenic low back pain. In the current study, the sensory innervation of the dorsal portion of the L5-L6 intervertebral disc was investigated, because the disc anatomically corresponds to the L4-L5 disc in humans, and the dorsal portion of the human L4-L5 disc is frequently subject to injury that causes low back pain. METHODS: A retrograde transport of Fluoro-Gold (F-G; Fluorochrome, Denver, CO) was used. Subjects included nontreated control (n = 32) and sympathectomized rats in which paravertebral sympathetic trunks were removed from L2 to L3 (n = 9). In a ventral approach, Fluoro-Gold crystals were placed on the dorsal portion of the L5-L6 disc, and labeled neurons in the bilateral dorsal root ganglia from T10 to L6 were counted. RESULTS: Fluoro-Gold crystals did not leak from the dorsal portion of the L5-L6 disc in 14 of the 32 nontreated rats and in 5 of the 9 sympathectomized rats. These rats were used for analysis. Fluro-Gold-labeled neurons were found in dorsal root ganglia from T13 to L6 in the 14 control rats but only from L2 to L6 in the 5 sympathectomized rats. CONCLUSION: The dorsal portion of the L5-L6 disc of rats was shown to be multisegmentally innervated by the T13 to L6 dorsal root ganglia. The sensory fibers from T13, L1, and L2 dorsal root ganglia were shown to innervate the dorsal portion of the L5-L6 disc through the paravertebral sympathetic trunks. In contrast, those from the L3-L6 dorsal root ganglia may innervate the dorsal portion of the L5-L6 disc through the sinuvertebral nerves.     

Adenoviral gene transfer in the peripheral nervous system

Background Viral vectors have gained widespread use as vehicles for somatic gene transfer, and the targeted expression of foreign proteins by these vectors offers advantages over the systemic administration of the drugs in some therapeutic situations. Selective virus-mediated gene transfer to the peripheral nervous system (PNS), however, remains to be established. There are no data showing efficiency of protein transduction in the PNS, which consists of a variety of cell types, many of which are postmitotic. Methods We prepared the first-generation replication-deficient recombinant adenovirus vectors engineered to express LacZ. Eight-week-old Wister rats were used in this study. Adenovirus vector (5 μl) containing the LacZ gene (5 × 10⁸ pfu) was injected into rat sciatic nerves or the dorsal root ganglia at the level of L5. The sciatic nerves, the dorsal root ganglia, and the spinal cords were obtained 7, 14, 21, and 28 days after injection. Expression of LacZ was assessed by X-gal histochemistry and β-gal immunohistochemistry. Results Following injection of the adenovirus carrying the LacZ gene into the sciatic nerve, LacZ expression was seen mainly in the Schwann cells and the small neurons in the dorsal root ganglion. In contrast, expression was observed in the primary nerve terminals of the spinal dorsal horn and the small to large dorsal root ganglion neurons and the Schwann cells after injection of the vectors into the L5 dorsal root ganglion. There were no side effects in rats with injection in the dorsal root ganglia or the sciatic nerve. Conclusions The present study shows efficient protein transduction by adenovirus vectors in the PNS. It is noted that injection of the virus into the dorsal root ganglia leads to extensive expression of LacZ in the spinal cord, the dorsal root ganglia, and the sciatic nerves.     

腰_5神经根孔外卡压症的诊断与手术治疗

目的 :分析腰 5 神经根孔外卡压症的病理解剖、诊断特点和手术治疗。方法 :对 2 4例腰 5 神经根孔外卡压症病人的临床手术资进行了回顾性研究。结果 :术后对其中的 18例病人进行了 0 .5年 -5年 ,平均 3.5年的随访观察 ,手术优良率达 94.5 %。结论 :孔外区腰 5 神经根卡压症的致病因素为孔外型椎间盘突出 ,椎间隙退变狭窄 ,腰骶椎滑脱 ,腰 5 椎体侧方骨质增生 ,腰 5 横突及骶骨翼肥大等。其诊断依赖于腰 5 根性卡压症、CT扫描或 MRI。手术减压是其有效的治疗方法 ,它包括经椎管入路、椎管旁入路或椎管内、外联合入路 ,术中应注意神经结构的识别和保护     

Immunoneutralization of nerve growth factor in lumbosacral spinal cord reduces bladder hyperreflexia in spinal cord injured rats

PURPOSE: We investigated the effects of intrathecal application of nerve growth factor (NGF) antibodies (Ab) on bladder hyperreflexia in chronic spinalized rats. MATERIALS AND METHODS: In adult female rats an intrathecal catheter was implanted at the level of the L6 to S1 spinal cord, followed by complete transection of the Th8 to 9 spinal cord. At 10 days after spinalization the intrathecal catheter was connected to an osmotic pump for continuous delivery of vehicle or NGF Ab (10 microg daily) for 2 weeks. Awake cystometry was then performed. NGF levels in the L5 to S1 dorsal root ganglia, L6 spinal cord and bladder were also measured using enzyme-linked immunosorbent assay. RESULTS: The number of uninhibited bladder contractions per voiding cycle, maximal pressure of uninhibited bladder contraction and maximal voiding pressure were significantly decreased in NGF Ab treated versus vehicle treated spinalized rats. Intercontraction interval, baseline intravesical pressure, pressure threshold for voiding and voiding efficiency were not significantly changed by NGF Ab treatment. NGF levels in the bladder, L6 spinal cord and L5 to S1 dorsal root ganglia of vehicle treated spinalized rats was 1.6 to 4.8 times higher than in spinal cord intact rats. After intrathecal NGF Ab treatment NGF levels were significantly lower in the L6 to S1 dorsal root ganglia (30% to 35%) and L6 spinal cord (53%) but not in the bladder or L5 dorsal root ganglia compared with levels in vehicle treated spinalized rats. CONCLUSIONS: Increased levels of NGF in the bladder, spinal cord and dorsal root ganglia were associated with bladder hyperreflexia after spinal cord injury. Immuno-neutralization of NGF in the spinal cord suppressed NGF levels in the L6 to S1 dorsal root ganglia, which contain bladder afferent neurons, and also suppressed bladder hyperreflexia. Thus, suppression of NGF levels in afferent pathways could be useful for treating bladder hyperreflexia associated with spinal cord injury.     

Characteristics of nerve root compression caused by degenerative lumbar spinal stenosis with scoliosis

BACKGROUND CONTEXT: In degenerative lumbar spinal stenosis with scoliosis (DLS), many authors stated that nerve root compression is almost always seen on the concave side of the scoliosis, and L4 and L5 nerve roots are the most often involved. However, there are few reports on the relationship between nerve root compression and the pattern of scoliosis. PURPOSE: To investigate the factors that may contribute to radiculopathy in DLS and their association with the pattern of the scoliosis. STUDY DESIGN: Retrospective analysis. METHODS: Twenty-two consecutive patients with DLS with radiculopathy were examined. The symptomatic nerve roots were determined by pain distribution, neurological findings and nerve root infiltration using lidocaine. The compressive factors were diagnosed by magnetic resonance imaging or myelography, discography, computed tomography after myelography or discography and radiculography. The pattern of scoliosis was determined in plain radiographs. We evaluated the correlation between the affected nerve root and the compressive factors or the pattern of the scoliosis. RESULTS: The L3 root was affected in 23% of patients; L4 root in 68%, L5 root in 55% and S1 root in 18%. L3 and L4 roots were more compressed by foraminal or extraforaminal stenosis on the concave side of the curve, whereas L5 and S1 roots were commonly affected by lateral recess stenosis on the convex side. The Cobb angle and the lateral slip of the cases in which L3 or L4 root was affected were significantly larger than in cases in which L5 or S1 root was compressed. CONCLUSIONS: In the treatment of radiculopathy caused by DLS, it is important to bear in mind that L3 or L4 roots were more strongly compressed by foraminal or extraforaminal stenosis at the concave side of the curve, whereas L5 or S1 nerve roots were affected more by lateral recess stenosis at the convex side of the curve.     

Characteristics of L3 nerve root radiculopathy

Background

In degenerative lumbar spinal disease with nerve root compression, the L5 and S1 nerve roots are the most often affected and the L3 nerve root is involved infrequently. The purpose of this study was to investigate the characteristics of L3 nerve root radiculopathy.

Methods

Seventeen consecutive patients with L3 radiculopathy were treated. The symptomatic nerve roots were determined by the pain distribution, the neurologic findings, and selective nerve root injection. The clinical characteristics and outcomes of these patients were assessed retrospectively.

Results

The average age was 76 years. The spinal diseases that were associated with L3 radiculopathy were lumbar canal stenosis in 6 patients, lumbar extraforaminal stenosis and lumbar disk herniation in 5 each, and lumbar canal stenosis with degenerative scoliosis in 1. The patients' symptoms were thigh pain in 12 patients, and hip or knee pain in 5. Four patients were nonambulatory because of severe pain. Although a sensory disturbance was reported in 9 patients, motor weakness was present in 2. Selective nerve root injection was completely effective in 10 patients. Six had decompressive surgery and/or fusion followed by a favorable outcome. Four patients were misdiagnosed and received conservative treatment for hip and/or knee joint diseases.

Conclusions

L3 radiculopathy was characterized by various lower limb pain and neurologic deficit. Selective nerve root injection was effective for most patients. In elderly patients who do not respond to treatment for hip and/or knee joint diseases, L3 nerve root radiculopathy should be considered as the cause of lower limb pain.     

腰骶神经节异位致腰腿痛(附5例报告)

论文对５例腰骶神经节变异和１例神经鞘膜瘤的诊治，目的：对其神经节变异的认识，以及与神经鞘膜瘤的鉴别加以讨论。方法：从１９９４－１９９６年，搜集到５例神经节异位，另有１例为神经鞘膜瘤，全部病例均为男性，年龄２３－５８岁，平均４２岁，职业均为体力劳动者，异位的部位，Ｌ３，４间隙左侧１例，Ｌ４，５间隙右侧１例，Ｌ５Ｓ１间隙右侧２例，Ｌ５Ｓ１间隙左侧１例，全部病例均手术治疗，结果：认为腰骶神经节变异是解剖生理变异，一般不会产生症状，只有合并侧隐窝狭窄时才会出现症状，所以常误诊为“腰椎间盘突出症”，结论对神经节异位ＣＴ有助于诊断，而磁共振要高于ＣＴ，与神经鞘膜瘤的鉴别影像学者很难将两者区分开来，手术是较好的鉴别方法，对于神经节不能冒然切除     

腰椎后路髓核摘除术中找不到突出物的原因探讨

目的：探讨腰椎髓核摘除术中找不到突出物的原因。方法：回顾分析术中找不到突出物１７例的原因,其中男１１例,女６例,年龄３０～５７岁,平均４２５岁。初次手术确诊１４例,再次手术确诊３例。结果：定位错误２例,特殊类型腰椎间盘突出症６例（极外侧型２例,游离型３例,硬膜囊内型１例）,骶管硬膜外蛛网膜囊肿２例,腰骶神经根疾患２例,腰椎管内肿瘤２例,腰骶神经后根节卡压征１例,腰骶神经根解剖变异１例,其他罕见原因１例。结论：术前认真问病史,细致查体,有目的地选择影像学检查,术中再次定位,扩大显露,仔细探查是减少腰椎间盘突出症漏误诊的关键。     

Clinical applications of diffusion magnetic resonance imaging of the lumbar foraminal nerve root entrapment

Diffusion-weighted imaging (DWI) can provide valuable structural information about tissues that may be useful for clinical applications in evaluating lumbar foraminal nerve root entrapment. Our purpose was to visualize the lumbar nerve root and to analyze its morphology, and to measure its apparent diffusion coefficient (ADC) in healthy volunteers and patients with lumbar foraminal stenosis using 1.5-T magnetic resonance imaging. Fourteen patients with lumbar foraminal stenosis and 14 healthy volunteers were studied. Regions of interest were placed at the fourth and fifth lumbar root at dorsal root ganglia and distal spinal nerves (at L4 and L5) and the first sacral root and distal spinal nerve (S1) on DWI to quantify mean ADC values. The anatomic parameters of the spinal nerve roots can also be determined by neurography. In patients, mean ADC values were significantly higher in entrapped roots and distal spinal nerve than in intact ones. Neurography also showed abnormalities such as nerve indentation, swelling and running transversely in their course through the foramen. In all patients, leg pain was ameliorated after selective decompression (n = 9) or nerve block (n = 5). We demonstrated the first use of DWI and neurography of human lumbar nerves to visualize and quantitatively evaluate lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for diagnosis of lumbar nerve entrapment.     

Pudendal nerve topography in the rat spinal cord projections studied with the axonal tracer wheat germ agglutinin conjugated-horseradish peroxidase.

The spinal cord termination of the sensory fibers of the rat pudendal nerve has been determined by using the transganglionic transport of horseradish peroxidase conjugated to wheat germ agglutinin. The gross anatomical examination of the pudendal plexus indicated the existence of dorsal and ventral branches in the sensory division of the pudendal nerve. Either branch or both were sectioned and exposed to a 1% solution of the enzyme. After an average survival period of 48 hours, the resulting reaction product was studied both at the level of the dorsal root ganglia and the spinal cord. Labeled dorsal root ganglion cells were observed between L1 and S4 (peak in S1 and L6). Evidence of transganglionic transport of the tracer was observed from L5 to S2. The ventral branch projected medially in the superficial dorsal horn, while the dorsal branch projected laterally. Our findings are consistent with a segregation of sensibilities for the ventral and dorsal branches that convey urogenital (ventral branch) and anal (dorsal branch) cutaneous sensations at the level of termination of primary afferents.     

Effect of nucleus pulposus on the neural activity of dorsal root ganglion

STUDY DESIGN: This study was designed to investigate, using neurophysiologic techniques in an in vivo rat model, the effect of application of nucleus pulposus to the nerve root on the neural activity of the dorsal root ganglion and the corresponding receptive fields. OBJECTIVES: To assess a further role of the dorsal root ganglion in mechanisms of radicular pain in lumbar disc herniation. SUMMARY OF BACKGROUND DATA: It has been suggested that the epidural application of autologous nucleus pulposus without mechanical compression causes nerve root inflammation and related radicular pain in lumbar disc herniation. Concerning the dorsal root ganglion, its mechanical hypersensitivity and potential for generating ectopic discharges have been reported. However, the effect of autologous nucleus pulposus on the dorsal root ganglion is uncertain. METHODS: In adult Sprague-Dawley rats spontaneous neural activity was recorded from the surgically exposed L5 dorsal root using electrophysiologic techniques, and the mechanosensitivity of L5 dorsal root ganglia and corresponding receptive fields on the hind paw were measured using calibrated nylon filaments. Autologous nucleus pulposus from the tail or fat was implanted at the L5 nerve root. Neural activity was monitored for 6 hours. RESULTS: Spontaneous neural activity in the nucleus pulposus group gradually increased and showed significant differences compared with the fat group from 2.5 to 6 hours after exposure. The mechanosensitivity of the dorsal root ganglia showed significant increases compared with the fat group. CONCLUSIONS: After application of nucleus pulposus to the nerve root, the dorsal root ganglion demonstrated increased excitability and mechanical hypersensitivity. These results suggest that nucleus pulposus causes excitatory changes in the dorsal root ganglion.     

神经生长因子保护脊髓背根神经节的实验研究

坐骨神经损伤后，在相应节段脊髓神经元可出现变性。为了观察外源性神经生长因子（ＮＧＦ）的保护作用而设计了本实验。方法是切断ＳＤ大鼠单侧坐骨神经，损伤局部给予外源性ＮＧＦ。借助酶组织化学及图像分析检测坐骨神经切断及应用ＮＧＦ后所引起的脊髓内抗氟化物酸性磷酸酶（ＦＲＡＰ）的活性变化，以探讨ＮＧＦ对脊髓背根神经节的保护作用。结果发现：坐骨神经切断可导致脊髓内ＦＲＡＰ含量降低，从而提示坐骨神经损伤可损害背根神经节；应用ＮＧＦ可显著减少这一酶含量的降低，从而首次从体内酶学水平证实ＮＧＦ对脊髓背根神经节有明显的保护作用。     

The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) se-quence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had radiculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. Received: March 6, 2000 / Accepted: October 20, 2000     

Synovial cyst--an unusual cause of nerve root compression. A case report

An elderly woman presented with a tense, synovia-lined ganglion, associated with the left L3/L4 apophyseal joint, which protruded posteriorly and caudally through the joint capsule and extended anteriorly and cephally into the neural canal. The intraspinal extension produced a compression radiculopathy of the L3 nerve root. Removal of the cyst produced acute and dramatic alleviation of the symptoms.     

腰椎髓核摘除术中找不到突出物的原因及对策

探讨腰椎髓核摘除术中找不到突出物的原因及处理对策。方法回顾性研究中找不到突出物１７例的原因,其中男１１例,女６例,年龄３０－５７岁,平均４２．５岁。初次手术确诊１４例,再次手术确诊３例。结果定位错误２例,特殊类型腰椎间盘突出症６例,易被误诊为腰椎间盘突出症的疾患９例。     

Origin and pathway of sensory nerve fibers to the ventral and dorsal sides of the sacroiliac joint in rats.

The purpose of this study is to clarify sensory innervation in the ventral and dorsal sides of the sacroiliac joint. Fluoro-gold, a neural tracer, was injected into the left sacroiliac joint of adult rats from the dorsal side after denervation of the dorsal side, and the bilateral dorsal root ganglia (DRGs) from T13 to S4 were examined by fluorescence microscopy five days after injection. In another rat group, the DRGs were examined using the same methods after injection of fluoro-gold from the ventral side. In the case of dorsal denervation (ventral nerve supply), labeled neurons were mainly located in the ipsilateral DRGs from L1 to S2. On the other hand, in the case of ventral denervation (dorsal nerve supply), labeled neurons were noted in the ipsilateral DRGs from L4 to S2. The sacroiliac joint in rats is innervated differently on the ventral and dorsal sides: the sensory nerve fibers to the dorsal side of the sacroiliac joint were derived from the DRGs of lower lumbar and sacral levels (from L4 to S2); and those to the ventral side from the DRGs of upper lumbar, lower lumbar, and sacral levels (from L1 to S2).     

大鼠坐骨神经切断后VEGF及其受体flk-1在脊髓与脊神经节中的表达

目的观察大鼠坐骨神经切断后脊髓与神经节组织中血管内皮生长因子(VEGF)及其胎肝激酶-1(flk-1)受体的表达变化规律。方法取成年雄性Wistar大鼠45只，对照组5只，实验组切断双侧坐骨神经后，在术后8h、24h、72h、5d、7d、10d、14d、21d取L4～L6段脊髓与相应脊神经节组织，采用免疫组织化学方法和图像分析技术，对VEGF及其flk-1受体的表达进行检测与分析。结果大鼠正常脊髓与神经节组织中均存在VEGF及flk-1的表达，坐骨神经切断后其表达可反应性地增强，持续一段时间后迅速回落至正常水平。并且flk-1在胶质细胞及白质中的神经纤维也有所表达。结论本实验从中枢神经元的角度揭示VEGF促周围神经再生机制，为今后进一步应用VEGF治疗外周神经损伤奠定基础。