Comparing the anatomical consistency of the posterior superior iliac spine to the iliac crest as reference landmarks for the lumbopelvic spine: a retrospective radiological study

A palpation reference line coursing between the superior-most aspect of the iliac crests has been reported to cross the L4 spinous process or L4/L5 intervertebral space in approximately 80% of the population. Comparable data have not been defined for the line coursing between the posterior superior iliac spines (PSIS). The purpose of this study was to compare the anatomical consistency of the PSIS to the iliac crest as landmarks used for spinal palpation. One hundred computerized tomographic images were reviewed in a three-dimensional setting. Two horizontal lines were constructed on each image: Line 1 representing the superior-most aspect of the iliac crest and Line 2 representing the inferior margin of the PSIS. The vertical distance between each horizontal line and the inferior edge of its respective spinous process were measured. The PSIS corresponded to the S2 spinous process in 81% of subjects and the iliac crest to the L4 spinous process in 59% of subjects. Distance measures suggest that the PSIS was closer to S2 versus the iliac crest to L4 (t = 6.998; P < 0.01). The PSIS crossed S2 more frequently than the iliac crest crossed L4 (chi(2) = 12.719, P < or = 0.01). The study findings support the relationship between the PSIS, and the spinous process of S2 is more consistent when compared to the iliac crest and the spinous process of L4. The PSIS reference line may be used to find S2 as a reference standard in validity and reliability palpation studies in the lower lumbar spine.     

经第1～3骶后孔上下缘水平切除骶骨对骶髂关节面面积的影响

目的 研究经第1-3骶后孔上、下缘水平切除骶骨对骶髂关节面面积的影响。方法 观测50例成人干燥骶骨标本（男28例，女22例）及其骶髂关节面，并测量关节面面积以及经第1～3骶后孔上、下缘水平切除骶骨时所切除的骶髂关节面的面积，并计算出该切除面积占骶髂关节面面积的百分比。结果 男性经第1骶后孔上、下缘，第2骶后孔上、下缘切除的骶髂关节面所占的平均面积百分比为：72．6％、47．5％、22．4％、12．3％。1例（3．57％）经第3骶后孔上缘可切除约5．0％的关节面。女性各百分比为：76．1％、53．8％、26．4％、17．0％。2例（9．09％）经第3骶后孔上缘可切除约9％的关节面。结论 经第3骶后孔上缘水平切除骶骨对骶髂关节的稳定性影响不大。     

股外侧皮神经在髂前上棘附近的解剖学和超声观察

目的 感觉异常性股痛(MP)常由股外侧皮神经(LFCN)的机械嵌压引起,通常发生在股外侧皮神经走行至髂前上棘的部位。MP最佳手术治疗方法有待确定,部分原因是LFCN周围筋膜平面的精细结构尚未阐明。本研究的目的是利用生物塑化和超声确定LFCN在髂前上棘附近的筋膜结构。方法 选择11具尸体（6名女性,5名男性, 38～97岁）制作薄层生物塑化切片。对34名健康志愿者（19名女性,15名男性,20～62岁）进行LFCN超声评估。结果 LFCN在腹内斜肌筋膜纤维和髂筋膜之间出骨盆,然后在缝匠肌表面和位于髂前上棘（ASIS）下方的阔筋膜张肌之间走行。在缝匠肌和阔筋膜张肌之间,LFCN走行在独立封闭的筋膜鞘中。结论 LFCN在髂前上棘处位于腹内斜肌腱膜内。LFCN在缝匠肌表面及外侧走行至大腿前外侧区域。超声定位LFCN有助于外科手术。     

Giant-cell ependymoma: Presentation of a case of the sacral region and literature review

Ependymoma is a rare central nervous system neoplasm with an even rarer morphologic variant called giant-cell ependymoma (GCE). GCE has a characteristic discrepant, malignant-like morphology but indolent behavior. We present the case of a 21-year-old female with an extra-axial GCE located in the sacral region. To date, 16 cases of sacral GCE have been reported in the literature, with 4 cases in the sacral region; however, all those cases were intra-axial. We present the first case of an extra-axial sacral GCE.     

Bariatric barosensor: a new paired structure in the paravetebral region of the iliac crest

A new anatomical entity, which we have decided to name bariatric borosensor, is described. It represents a paired structure under the skin, supero-lateral to the posterior superior iliac spine, overlying the iliac crest at the level of the fourth lumbar vertebra. Each of the paired structure is about the size of an enlarged lymph node; 0.5-2.0 cm in the largest diameter, spherical or ovoid in shape and firm in consistency. They are easily palpated clinically and can be demonstrated objectively by ultrasound examination. A hypothesis is put forth, conjecturing that this new structure may have relevance to the problem of obesity in modern, civilised western societies.     

The course of the greater occipital nerve in the suboccipital region: a proposal for setting landmarks for local anesthesia in patients with occipital neuralgia

The anatomical relationships of the greater occipital nerve (GON) to the semispinalis capitis muscle (SCM) and the trapezius muscle aponeurosis (TMA) were examined to identify topographic landmarks for use in anesthetic blockade of the GON in occipital neuralgia. The course and the diameter of the GON were studied in 40 cadavers (29 females, 11 males), and the points where it pierced the SCM and the TMA were identified. The course of the GON did not differ between males and females. A left-right difference was detected in the site of the GON in the TMA region but not in the SCM region. The nerve became wider towards the periphery. This may be relevant to entrapment of the nerve in the development of occipital neuralgia. In three cases, the GON split into two branches before piercing the TMA and reunited after having passed the TMA, and it pierced the obliquus capitis inferior muscle in another three cases. The GON and the lesser occipital nerve reunited at the level of the occiput in 80% of the specimens. The occiput and the nuchal midline are useful topographic landmarks to guide anesthetic blockade of the GON for diagnosis and therapy of occipital neuralgia. The infiltration is probably best aimed at the site where the SCM is pierced by the GON.     

Transvaginal sonography and rectal endoscopic sonography for the assessment of pelvic endometriosis: a preliminary comparison

BACKGROUND: Endometriosis and possible rectal involvement are difficult to assess by physical examination. Previous studies have shown the diagnostic value of magnetic resonance imaging and rectal endoscopic sonography (RES) in this setting, but not that of transvaginal sonography (TVS). The aims of this study were to compare the accuracy of TVS and RES for the diagnosis of pelvic endometriosis, and to compare the results with histological findings. PATIENTS AND METHODS: In a prospective study, 30 consecutive patients referred with clinical signs of endometriosis underwent TVS and RES; the images were interpreted blindly with regard to physical findings. RESULTS: Endometriosis was confirmed histologically in 28 (93%) of the 30 patients. Endometriomas were also present in 67% of cases. For the diagnosis of uterosacral endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 75 and 75%, 83 and 67, 95 and 90%, and 45 and 40% respectively. For the diagnosis of rectosigmoid endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 95 and 82%, 100 and 88%, 100 and 95%, and 89 and 64% respectively. CONCLUSION: Despite the large proportion of our patients who had intestinal endometriosis, representing a possible source of bias, our results suggest that TVS is as efficient as RES for detecting posterior pelvic endometriosis and should therefore be used as the first-line examination.     

Anatomy and landmarks for branches of the brachial plexus: a vade mecum

Exploration and repair of the brachial plexus and its branches demands a good comprehension of its intricate anatomy. To this end, landmarks for identifying this anatomy may prove useful to the clinician and surgeon. As such, a specific collection is lacking in the literature. Therefore, the following review of salient surgical anatomy and regional landmarks of the brachial plexus and its branches is provided. Our hopes are that these data will be useful during clinical and surgical procedures of these regions and act as a single, concise source for such information.     

后纵韧带硬化对颈椎力学影响的三维有限元分析

目的利用三维有限元分析探讨后纵韧带(posterior longitudinal ligament,PLL)硬化后对颈椎生物力学的影响,分析探讨其可能引起的颈部稳定性改变。方法对1位健康成年男性进行颈部CT及MR扫描,获取C1—C7节段的断层图片,采用MIMICS(Version 12)软件对颈椎图像进行三维重建,用HYPERMESH 10.0软件对三维几何进行网格划分,后处理计算软件为LS-DYNA3D 971。模型开发和模拟计算在Dell Power Edge 12G M420刀片式服务器上进行,并固定C7,对C1进行前屈、仰伸及轴向旋转运动,加载力矩为3 N·m。比较在前屈、仰伸及旋转运动下,正常以及PLL硬化后颈椎有限元模型的生物力学改变对颈部稳定性的影响。结果颈椎前屈运动中,PLL硬化后椎间盘纤维环最大应力减小6%。颈椎仰伸运动中,PLL硬化后髓核最大应力降低约11%,椎小关节最大应力增大约15.7%。颈椎旋转运动中,PLL硬化椎间盘纤维环最大应力降低24%,最大应力集中在C4/5纤维环旋转方向侧;髓核最大应力降低25%,且最大应力位置由C2/3髓核上方下移至C6/7髓核下方;椎小关节最大应力下降10%。结论 PLL硬化后,前屈及旋转运动使PLL承载更多的力,可能加重已有病变或引起继发损伤;仰伸运动会使最大受力部位转移到椎小关节,导致继发性椎小关节损伤的可能性增加。     

Anatomical landmarks in the paediatric distal radius: a new method for measuring epiphyseal height

Purpose  

Elastic stable intramedullary nailing for fixation of paediatric forearm fractures has become the preferred method of osteosynthesis. The aim of the study was to develop a method for finding the correct entry point in the distal radius of children of all ages as a distance from the radial styloid, a landmark which is readily palpable at the wrist.     

Projections from the medial septum and diagonal band of Broca to the dorsal and central superior raphe nuclei: a non-cholinergic pathway

Summary The anatomical organization of projections from the medial septal nucleus (MS), and the vertical (VDB) and horizontal limb (HDB) of the diagonal band of Broca to the dorsal raphe nucleus (NRD) and the central superior raphe nucleus (RCS) of the rat were studied by anterograde [³H]-leucine, and True Blue and Fluoro Gold fluorescent retrograde tracing. Projections from the MS were found to enter the basal mesencephalon at the rostro-medial aspect of the pontine nuclei, curve dorsally and terminate throughout the RCS and in the caudal portion of the NRD. Fibers from the VDB were found to enter these raphe nuclei by two separate routes; some fibers reached the basal mesencephalon, curved dorsally and terminated in the RCS and NRD. Other fibers entered the pedunculopontine nucleus, curved medially and reached the NRD. Presumed terminal labelling was found overlaying the RCS and NRD throughout their rostro-caudal extensions. The brain stem projections from HDB entered the mesencephalon by the same routes as those from VDB, but the labelling over RCS was sparse, and the NRD labelling was preferentially distributed to the rostral portion of the nucleus. The present data indicate a crude topographic organization of the projections from the septal region to the NRD and RCS. In general, the distribution of presumed terminal labelling appeared to be more closely associated with the distribution of NRD and RCS 5-HT immunoreactive cell bodies, than with the cytoarchitectonically defined extensions of these raphe nuclei. By sequential evaluation of the distribution of retrogradely labelled and acetylcholine esterase-stained cells on the same section, and by selective tracing with radiolabelled choline, it appears that the vast majority, if not all, of the neurons in MS and diagonal band which project to the rostral raphe are non-cholinergic.Abbreviations CLi caudal linear raphe nucleus - DTg dorsal tegmental nucleus - flm medial longitudinal fasciculus - HDB horizontal limb of the diagonal band of Broca - IP interpeduncular nucleus - MS medial septal nucleus - NRD dorsal raphe nucleus - PAG periaqueductal gray - Pn pontine nucleus - R red nucleus - RCS central superior raphe nucleus - RMg raphe magnus nucleus - RPn pontine raphe nucleus - SN substantia nigra - VDB vertical limb of the diagonal band of Broca - VTg ventral tegmental nucleus - 5 trigeminal motor nucleus     

Evidence for glutamate as a neurotransmitter in spinothalamic tract terminals in the posterior region of owl monkeys

Previous studies have suggested that glutamate is a neurotransmitter in ascending somatosensory pathways to the thalamus. The present study examined with quantitative immunohistochemical methods the presence of glutamate in spinothalamic tract terminals of owl monkeys (Aotus trivirgatus). Such terminals in the posterior region, in which a nucleus was recently identified as a specific pain and temperature relay in macaques and humans, were labeled by anterograde transport of wheat germ agglutinin conjugated to horseradish peroxidase, injected into the spinal dorsal horn. Glutamate-like immunoreactivity was demonstrated with a postembedding immunogold procedure using a well-characterized glutamate antiserum. Quantitative analysis of the immunogold labeling demonstrated that the spinothalamic tract terminals contained more than twice the tissue average of glutamate-like immunoreactivity. Enrichment of glutamate-like immunoreactivity was also found in terminals of presumed cortical origin. Presynaptic dendrites, cell bodies and non-vesicle-containing dendrites diplayed low levels of glutamate-like immunoreactivity. A strong positive correlation (r=0.69; P<0.0001) was found between the density of synaptic vesicles and the density of gold particles in spinothalamic tract terminals, in contrast to a weak negative relationship (r= -0.28; P=0.089) present in GABAergic presynaptic dendrites. These data provide strong evidence that the gold labeling in the spinothalamic tract terminals represents transmitter labeling, implying that glutamate is a neurotransmitter for ascending nociceptive and thermoreceptive information in primates.     

Variations in the anatomy of the posterior auricular nerve and its potential as a landmark for identification of the facial nerve trunk: a cadaveric study

The posterior auricular nerve (PAN) is the first extracranial branch of the facial nerve trunk. It innervates the posterior belly of the occipitofrontalis and the auricular muscles and contributes cutaneous sensation from the skin covering the mastoid process and parts of the auricle. This study was carried out to provide a detailed account of its anatomy and to ascertain its reliability as a surgical landmark for the facial nerve. Eleven facial sides from six formalin-fixed cadavers were dissected. The course and arborisation pattern of the PAN was observed, and its position of emergence from the facial nerve trunk (FNT) was measured. The PAN arose from the posterolateral aspect of the FNT 1.6-11.1 mm from the stylomastoid foramen (5.4 ± 3.3 mm). It arose as a single branch (45.4%), or from a common trunk that divided into two (36.4%) or three branches (18.2%), with the other branches passing into the parotid gland. The PAN continued deep (63%), or lateral to the mastoid process (9.1%), or through the tissue of the parotid gland (27.3%). In all cases the PAN ran in a consistent, superficial location posterior to the external auditory meatus. The PAN takes a variable course; however, its consistent location behind the external auditory meatus makes it easily identifiable in superficial dissection, and therefore a potential surgical landmark for identifying the FNT.     

Modulations of the lateral geniculate nucleus cell responses by a second discrete conditioning stimulus: implications of the superior colliculus in rabbits

Summary This study analyzes the interactions between two discrete stimuli located in the visual field of the rabbit at the lateral geniculate level. Single unit recordings were carried out simultaneously from the superior colliculus (SC) and lateral geniculate nucleus (LGN) in anesthetized and paralyzed rabbits. A first conditioning stimulus (most often a moving target) was positioned in the receptive field of the collicular cell to ensure activation of the retino-collicular path. A second test stimulus was introduced into the receptive field of the LGN cell. The presentation of this latter stimulus was timed so as to fire the geniculate cell at various delays after the collicular neuron had responded to its own stimulus. The spontaneous firing of each cell was unaffected by the stimulus appropriate to the complementary unit. The conditioning collicular stimulus produced increases or decreases in geniculate responses. This modulation may eventually reduce the direction specificity of a geniculate unit. The fluctuations of the geniculate responses peaked 200 to 300 ms after collicular cells had responded. In a separate series of experiments the influence of the conditioning stimulus on geniculate responses was abolished when the SC was locally inactivated. These results suggest that the well documented colliculo-geniculate system mediates the interactions of several stimuli in the visual field. The outcome of this processing results in a modulation of geniculate responses.     

Connections between the supratemporal and its rostral areas, and the posterior thalamic region in the monkey: a retrograde HRP study.

Connections between the anterior half of the superior temporal gyrus (Ts) and the supratemporal plane (STP) in the Sylvian fissure, and the posterior thalamic region in the monkey were studied after retrograde transport of horseradish peroxidase (HRP). HRP injections into the Ts resulted in labeled cells in the posterodorsal division of the principal medial geniculate complex (GMpd), the suprageniculate and limitans nuclei, and the medial part of the medial nucleus of the pulvinar complex. HRP injections into the rostral Ts led to labeling in the posterior extremity of the GMpd, whereas injections into the caudal Ts resulted in labeling in the rostral GMpd. HRP injections into the area of transition between the Ts and STP led to labeling in the ventral part of the ventral division of the principal medial geniculate complex (GMv) and in the GMpd. HRP injections into the rostral STP led to labeling in the lateral part of the GMv, the anterodorsal division of the principal medial geniculate complex (GMad), and the lateral division of the posterior nucleus (Pol). HRP injections into the more caudal part of the STP yielded labeling in the more dorsomedial part of the GMv, Pol, and GMad. HRP injections into the lip of the STP yielded labeling in the GMv, Pol, GMad, and GMpd.     

Proposal for a new classification of variations in the iliac venous system based on internal iliac veins: a case series and a review of double and left inferior vena cava

There are many reports on variations in the inferior vena cava (IVC), particularly double IVC (DIVC) and left IVC (LIVC). However, no systematic report has recorded iliac vein (IV) flow patterns in the DIVC and LIVC. In this study, we examined IV flow patterns in both DIVC and LIVC observed during gross anatomy courses conducted for medical students and in previously reported cases. During the gross anatomy courses, three cases of DIVC and one case of LIVC were found in 618 cadavers. The IV flow pattern from these four cases and all other previously reported cases can be classified into one of the following three types according to the vein into which the internal iliac vein drained: the ipsilateral external IV; confluence of the ipsilateral external IV and IVC; and the communicating vein, which connects the IVC and the contralateral IVC or its iliac branch. This classification, which is based on the internal IV course, is considered to be useful because IV variations have the potential to cause clinical problems during related retroperitoneal surgery, venous interventional radiology, and diagnostic procedures for pelvic cancer.