脊柱椎管损伤模型建立的试验研究

目的 构建一种精确模拟椎体骨折的测试模型,通过试验比较椎管创伤后产生不同的变化和各自的特点,为临床手术提供科学依据.方法 研究在人脊椎标本应用冲击试验机测量标本,分别测出不同冲击力的椎管直径的试验参数并进行分析.结果 在产生最小的脊柱破裂后增加冲击力和椎管骨质破裂应变有交互作用(R2=0.85,P<0.05).结论 逐步增量法是构建脊柱外伤的一种可靠的方法.     

Dimensions of the lumbar spinal canal: variations and correlations with somatometric parameters using CT

The aim of this study was to investigate the correlation of vertebral dimensions with somatometric parameters in patients without clinical symptoms and radiological signs of central lumbar spinal stenosis. One hundred patients presenting with low back pain or sciatica were studied with CT. In each of the L3, L4 and L5 vertebra three slices were taken with the following measurements: 1. Slice through the intervertebral disc: (a) spinal canal area; (b) interarticular diameter; (c) interligamentous diameter. 2. Slice below the vertebral arcus: (a) dural sac area; (b) vertebral body area. 3. Pediculolaminar level: (a) anteroposterior diameter and interpedicular diameter of the spinal canal; (b) spinal canal area; (c) width of the lateral recesses. The Jones-Thomson index was also estimated. The results of the present study showed that there is a statistically significant correlation of height, weight and age with various vertebral indices. The conventional, widely accepted, anteroposterior diameter of 11.5 mm of the lumbar spinal canal is independent of somatometric parameters, and it is the only constant measurement for the estimation of lumbar spinal stenosis with a single value. The present study suggests that there are variations of the dimensions of the lumbar spinal canal and correlations with height, weight and age of the patient. Received 9 July 1997; Revision received 11 February 1998; Accepted 11 March 1998     

MR determination of neonatal spinal canal depth

Objectives

Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the spinal canal (mid-spinal canal depth – MSCD) may reduce the incidence of traumatic taps, but there is little data in extremely premature or low birth weight neonates. Here, we determined the spinal canal depth at post-mortem in perinatal deaths using magnetic resonance imaging (MRI).

Patients and methods

Spinal canal depth was measured in 78 post-mortem foetuses and perinatal cases (mean gestation 26 weeks; mean weight 1.04 kg) at the L3/L4 inter-vertebral space at post-mortem MRI. Both anterior (ASCD) and posterior (PSCD) spinal canal depth were measured; MSCD was calculated and modelled against weight and gestational age.

Results

ASCD and PSCD (mm) correlated significantly with weight and gestational age (all r > 0.8). A simple linear model MSCD (mm) = 3 × Weight (kg) + 5 was the best fit, identifying an SCD value within the correct range for 87.2% (68/78) (95% CI (78.0, 92.9%)) cases. Gestational age did not add significantly to the predictive value of the model.

Conclusion

There is a significant correlation between MSCD and body weight at post-mortem MRI in foetuses and perinatal deaths. If this association holds in preterm neonates, use of the formula MSCD (mm) = 3 × Weight (kg) + 5 could result in fewer traumatic LPs in this population.     

继发椎管狭窄与脊髓亚急性联合变性MRI异常信号的相关性

目的：研究脊髓亚急性联合变性(SCD)的 MRI 表现特点,探讨继发椎管相对狭窄与 SCD 的 MR 异常信号的相关性。方法收集56例 SCD 患者的临床及 MRI 影像资料,分析 SCD 病例中椎间盘膨出/突出、黄韧带增厚、后纵韧带增厚或两者以上协同作用下的椎管相对狭窄与脊髓内病灶的表现特点。结果56例 SCD 患者中,MRI 检查脊髓表现有病灶的45例,均表现为典型的SCD 影像表现。继发椎管相对狭窄并脊髓信号异常者37例,继发椎管相对狭窄脊髓未见异常信号者2例,无继发椎管相对狭窄脊髓信号异常者8例,无继发椎管相对狭窄脊髓也未见异常信号者9例。比较采用χ2检验统计继发椎管相对狭窄与脊髓异常信号有显著性差异(P <0.05)。37例 SCD 有继发椎管相对狭窄中15例行物理治疗后较对照组病程缩短。结论继发椎管相对狭窄致脊髓微循环障碍是导致 SCD 脊髓病变 MRI 表现更显著或更易于显现的重要因素。     

Congenital spondylolysis of cervical vertebrae with spondylolisthesis and frontal narrowing of the spinal canal

Summary Two cases of cervical spondylolisthesis, due to a congenital defect in the pars interarticularis of C₆, associated with spina bifida and elongation of the contralateral pars interarticularis, are reported. Tomography showed an abnormal direction of the articular facets of C₆ and demonstrated a narrow frontal diameter of the cervical spinal canal at the level of the malformation. Gas myelography showed a slight compression of the cord. Unlike previously reported cases the patients had neurological findings which, in one case at least, were certainly referable to the spinal cord.     

Widening of the spinal canal and dural ectasia in Marfan's syndrome: assessment by CT

We describe a method for diagnosing dural ectasia (DE) and spinal canal widening (SCW) using CT. We examined 23 patients with Marfan's syndrome (MFS), 17 with Ehlers-Danlos syndrome (EDS) and 29 normal subjects, using six axial slices at the level of the L1-S1 pedicles. Transverse diameters of the vertebral bodies, spinal canal and dural sac were measured and indices were defined to differentiate patients with DE and SCW from normal. Statistical significance was assessed using Student's t -test, χ ²-test and Pearson's correlation coefficient. DE and SCW occurred in 69.6 % and 60.9 % of cases of MFS and in 23.5 % and 35.3 % of EDS respectively. In MFS, prevalence was significantly higher than in the control group. DE was significantly more frequent in MFS than in EDS. A strong correlation existed between DE and SCW in MFS and the control group, but not in EDS. Our system enables quantitative assessment of SCW and DE. The latter is particularly important in subjects suspected of having MFS, in whom it is a common and characteristic sign. Received: 28 September 1998 Accepted: 16 March 1999     

Morphological analysis of the cervical spinal canal,dural tube and spinal cord in normal individuals using CT myelography

To verify the conventional concept of developmental stenosis of the cervical spinal canal, we performed a morphological analysis of the relations of the cervical spinal canal, dural tube and spinal cord in normal individuals. The sagittal diameter, area and circularity of the three structures, and the dispersion of each parameter, were examined on axial sections of CT myelograms of 36 normal subjects. The spinal canal was narrowest at C4, followed by C5, while the spinal cord was largest at C4/5. The area and circularity of the cervical spinal cord were not significantly correlated with any parameter of the spinal canal nor with the sagittal diameter and area of the dural tube at any level examined, and the spinal cord showed less individual variation than the bony canal. Compression of the spinal cord might be expected whenever the sagittal diameter of the spinal canal is below the lower limit of normal, that is about 12 mm on plain radiographs. Thus, we concluded that the concept of developmental stenosis of the cervical spinal canal was reasonable and acceptable.     

腰椎管狭窄再手术的临床分析

 目的 探讨腰椎管狭窄术后再手术的常见原因, 寻求再手术时术中和术后的应对措施。方法 回顾性分析我科收治的21例腰椎管狭窄症再手术患者的临床资料。全部患者均经过先期后路减压手术, 部分经过后路内固定, 由于症状不缓解或再次出现症状而采取后路再手术, 分析再手术的原因、术后疗效和相关的手术操作过程。结果 本组再手术的原因主要包括：减压不彻底、腰椎不稳、螺钉位置偏差、椎间盘突出术后复发、术式选择欠妥等, 再手术前JOA评分为11.28±2.67, 再手术后的患者均得到随访和定期复查, 随访时间12~36个月, 平均24.8个月, 随访终末JOA评分及改善率为（19.45±2.79）%和（45.34±7.87）%, 术后下肢感觉、肌力和功能障碍得到明显恢复。结论 严格掌握手术适应证, 有效的减压, 合理的内固定, 可以使再手术的患者获得较好的疗效。     

新的MRI分级标准对评估退行性颈椎椎管狭窄的临床意义

目的 DCSS(degenerative cervical spinal stenosis,DCSS)新的MRI分级标准与临床症状体征相关性的研究。方法两位MRI医师分析经临床和影像学检查确诊的100例DCSS患者的MRI表现,应用Kang提出的分级标准,测量C2/3,C3/4,C4/5,C5/6,C6/7平面椎管狭窄程度及分级,并研究患者临床症状体征做一个相关性分析。结果两位医师在对DCSS新的分级标准的应用上组间一致性很好(k=0.955),同时新的分级标准与临床症状也有很好的相关性,0级患者一般无明显阳性体征,2~3级患者中,几乎都表现出阳性神经系统表现,1级患者则必须与临床密切结合。结论新的MRI分级标准对评估颈椎椎管狭窄对临床诊断有很好的指导意义,随着分级的不断提高,患者的体征也愈发明显。     

老年重度腰椎管狭窄症围术期特点及其术后早期并发症

 目的 探讨老年重度腰椎管狭窄症围术期特点和术后早期并发症的处理方法。方法 回顾性分析我院骨科2008-02至2013-12共184例老年重度腰椎管狭窄症的病历资料,总结术前合并症、术中出血量、手术时间、住院时间,观察术后早期并发症的出现情况,总结处理方法。结果 患者平均(68.77±5.76)岁,平均住院时间(27.26±9.61)d,无围术期死亡病例,手术时间平均(3.09±1.09) h,术中出血量平均(618.60±366.50)ml,融合节段超过3个的106例(57.61％)。出现各种并发症合计119例(64.67％),按发生的比例依次排列为切口愈合不良、术后疼痛、全身状况不稳定、低血容量、脑脊液漏、神经根损伤和深静脉血栓形成,对所发生的并发症,均给予了积极有效的对应治疗,效果较好。结论 老年重度腰椎管狭窄症患者的手术有一定的风险,但并非不能手术,做好术前准备和术后应对预案,可以提高围术期安全性。     

Paragangliomas of the spinal canal

We report the clinical MRI and histopathological features of five consecutive cases of spinal paraganglioma. Three intradural tumours were found in the typical location (two at the L4, one at the S2 level); one intradural extramedullary tumour arose at an unusual level, from the ventral C2 root, and one extradural tumour growing along the L5 nerve root sheath had an aggressive growth pattern with early, local paraspinal recurrence and, eventually, intradural metastatic spread. This type of growth pattern has not been described previously. Paragangliomas of the spinal canal are more common than previously thought and can be located anywhere along the spine, although the lumbosacral level is the most common. Their appearance on MRI can not disinguish them from other tumours in the spinal canal. Even though paragangliomas in general are benign and slowly growing their growth pattern can vary and be more aggressive, to the point of metastatic spread. Received: 14 December 1998 Accepted: 27 January 1999     

Ability of two radiographic methods to identify the closeness between the mandibular third molar root and the inferior alveolar canal: a pilot study

Objectives

The aim was to compare the ability of two radiographic methods: the panoramic radiograph (PR) in combination with a 20-degree negative angle periapical radiograph (−20°Pa) vs two periapical radiographs Pa + (−20°Pa), in evaluating the closeness of the lower third molar root and the inferior alveolar canal.

Methods

2 radiographic methods of 32 impacted third molars were used. Two untrained dental students evaluated the closeness of the association between the root tip of the lower third molar and the inferior alveolar canal, both when in contact and separated, using dental cone beam CT as the gold standard. The position of the inferior alveolar canal relative to the third molar root was also recorded. The sensitivities and specificities of these findings were evaluated. Kappa values were used to assess the intra- and interobserver reliability.

Results

Of the 32 teeth, 23 (68.6%) showed contact between the root tip of the third molar and the inferior alveolar canal on dental cone beam CT, and 9 (31.4%) showed separation. The respective mean sensitivities of PR + (−20°Pa) and Pa + (−20°Pa) in detecting contact were 97.9% and 84.8% and the respective mean specificities in detecting separation were 16.7% and 44.4%. Intraobserver agreement in both techniques ranged from 0.69 to 0.94. The respective interobserver reliability was 0.88 in PR + (−20°Pa) and 0.75 in Pa + (−20°Pa).

Conclusions

Both the PR + (−20°Pa) and the periapical vertical tube-shift technique Pa + (−20°Pa) have high potential for detecting the closeness between the third molar root and the inferior alveolar canal.     

椎管内神经鞘瘤的低场MRI诊断

目的:探讨椎管内神经鞘瘤的低场MRI表现及诊断价值。方法:搜集12例经手术病理证实的椎管内神经鞘瘤,重点分析其MRI特点及发病部位。结果:本组病例肿瘤均为单发,T1WI肿瘤呈低或等信号,T2WI呈高信号,增强后显著强化,12例肿瘤病理均无钙化。MRI对椎管内神经鞘瘤定位诊断符合率100%,定性诊断符合率83.3%。结论:低场MRI可作为诊断椎管内神经鞘瘤的敏感检查方法,正确认识其MRI征象能帮助术前诊断,并指导手术。     

Marked canal stenosis at the level of the atlas

Summary A 38-year-old man with severe canal stenosis at the level of the atlas is reported. The clinical manifestations were muscular weakness and wasting of the upper limbs and spastic paresis of the lower limbs, which all progressed slowly. The atlas was hypoplastic and its retrodental space was narrow. The spinal cord was markedly compressed between the odontoid process and the posterior arch of the atlas. The clinical manifestations improved after a posterior laminectomy of the atlas.     

MRI对椎管内胚胎源性肿瘤的诊断价值

目的 探讨椎管内胚胎源性肿瘤的MRI表现特征并评价其诊断价值。方法 45例由手术病理证实的椎管内胚胎源性肿瘤患均经自旋回波（SE）、快速自旋回波（TSE）序列MR成像。对其MRI表现进行回顾性分析并与病理对照。结果 45例椎管内胚胎源性肿瘤中，18例表皮样囊肿中15例T1WI呈低信号，另3例为高倍号，所有18例T2WI呈不均质高信号；7例皮样囊肿T1WI呈混杂信号；9例畸胎瘤T1WI呈高、低或混染信号；11例脂肪瘤T1WI呈高信号。MRI对椎管内胚胎源性肿瘤术前定位和定性诊断准确率分别为100％（45／45）和80％（36／45）。结论 椎管内胚胎源性肿瘤的MR信号具有特征性，可反映瘤内组织成分，MR平扫结合增强扫描对其术前定位、定性诊断具有重要价值。     

椎管内血肿的影像学表现

目的探讨椎管内血肿的CT及MRI表现特点,提高椎管内血肿CT及MRI表现的认识。方法回顾分析18例经手术及临床治疗随访复查证实的椎管内血肿的CT及MRI表现。18例患者均常规CT、MR平扫,其中2例MR增强扫描。使用GE公司Lightspeed16CT扫描仪,及Phillip1．5TAcheive超导MR扫描仪,2例MR增强扫描采用钆喷酸葡甲胺（Gd—DTPA）对比剂经静脉团注,注射剂0．1mmol/kg。结果颈胸段3例,胸段5例,胸腰段6例,腰段4例;位于脊髓背侧方14例,脊髓两侧2例、腹侧2例。硬膜外血肿11例,硬膜下血肿6例,硬膜外血肿并蛛网膜下腔内积血1例。CT表现为高密度或等密度,MRI分别呈长T1长T2信号、长T-短Tz信号、等T1短T2信号及短T1长T2信号,其中2例MR增强扫描,1例边缘强化,1例未见强化。结论椎管内血肿的CT、MRI表现具有一定的特征性,对其定性定位诊断及鉴别诊断有着重要的价值。     

Further aspects of MR-signal enhancements in stenosis of the cervical spinal canal

Summary The validity and anatomical basis of increased MR-signal intensity of the cord in cervical canal stenosis is discussed with respect to our own data of 32 patients (including results of clinical, CSF and other imaging technique findings) and previous reports. A shear-stress hypothesis with edematous tissue changes is favoured.     

Upper cervical spinal cord compression due to bony stenosis of the spinal canal

Compression of the upper cervical spinal cord due to stenosis of the bony spinal canal is infrequent. In the first case reported here, stenosis was due to acquired extensive, unilateral osteophytes centered on the left apophyseal joints of C1–C2 in an elderly professional violinist. In the second case, stenosis was secondary to isolated congenital hypertrophy of the laminae of C1 and C2.     

Central spinal cord lesions in stenosis of the cervical canal

Summary 34 patients suffering from cervical spondylotic myelopathy confirmed by myelography were examined by delayed CT 6–10 h after myelography. Twelve patients showed bilateral intramedullary collections of contrast medium, predominantly cranial to the stenosis. In these patients males predominated, the duration of clinical symptoms lasted longer although their age was lower. There was no correlation to the degree and the extension of the narrowing of the cervical spinal canal. Half of 20 patients undergoing consecutive decompressive surgery showed intramedullary contrast enhancement, and this was shown again by postoperative MRI in eight. The postoperative clinical and neurophysiological results revealed no change in the majority of patients, but three patients showing intramedullary contrast medium deteriorated in neurophysiological outcome, while only one of the patients in whom intramedullary contrast medium was not noticed got worse.