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61.
This paper is a collection of computational, finite element studies on vertebroplasty performed in our laboratory, which attempts to provide new biomechanical evidence and a fresh perspective into how the procedure can be implemented more effectively toward the goal of preventing osteoporosis-related fractures. The percutaneous application of a bone cement to vertebral defects associated with osteoporotic vertebral compression fracture has proven clinical successful in alleviating back pain. When the biomechanical efficacy of the procedure was examined, however, vertebroplasty was found to be limited in its ability to provide sufficient augmentation to prevent further fractures without risking complications arising from cement extravasations. The procedure may instead be more efficient biomechanically as a prophylactic treatment, to mechanically reinforce osteoporotic vertebrae at risk for fracture. Patient selection for such intervention may be reliably achieved with the more accurate fracture risk assessments based on vertebral strength, predicted using geometrically detailed, specimen-specific finite element models, rather than on bone density alone. Optimal cement volume, placement, and material properties were also recommended. The future of vertebroplasty involving biodegradable augmentation material laced with osteogenic agents that upon release will stimulate new bone growth and increase bone mass was proposed. 相似文献
62.
Soft-tissue angiomatosis is a rare condition characterized by diffuse proliferation of benign vascular structures, accompanied by mature adipose tissue, which affect a large segment of the body in a contiguous fashion. Most patients present in childhood or adolescence. We report a case of large soft-tissue angiomatosis, located in the left forearm of a 65-year-old man, which showed extensive intramuscular and intermuscular infiltration, and embracement of the radius and the main vascular and neural bundles of the forearm. Due to the deep location, large size, ill-defined limits and non-homogeneous composition with areas suggestive of an adipose component in the radiological examination, the lesion raised the possibility clinically of a liposarcoma. The myxoid adipose tissue component of the lesion, a feature previously undescribed, and the predominance of small, capillary-sized vessels were considered concordant with the clinical diagnosis. This presentation is rare. The features of the lesion made complete surgical excision impossible and amputation of the extremity was considered the best treatment. The main differential diagnoses include infiltrating lipoma, myxolipoma, angiomyxolipoma, angiolipoma, intramuscular angioma, liposarcoma and low-grade myxofibrosarcoma. In conclusion, angiomatosis might simulate liposarcoma, particularly if the mass is large, heterogeneous, myxoid and appears later in life. 相似文献
63.
64.
目的 探讨寰椎因素致椎 基底动脉供血不足的发病机制及手术切开横突孔减压提供解剖学依据。方法 在5 0例中国成年人干燥寰椎标本上 ,对具有临床意义的数据进行解剖学测量。结果 寰椎横突孔与椎动脉沟的成角左侧为(6 7 87± 5 39)°,右侧为 (6 9 84± 4 5 5 )° ;椎动脉沟绕寰椎侧块成角 :左侧为 (6 2 4 6± 4 6 6 )°,右侧为 (6 3 6 1± 2 31)°。寰椎横突孔前壁厚度 :左侧为 (2 96± 0 5 4 )mm ,右侧为 (3 2 1± 0 4 0 )mm。横突孔后壁厚度 :左侧为 (2 2 8± 0 5 7)mm ,右侧为 (2 0 2± 0 2 6 )mm。以上数据左、右侧比较差异无显著性。结论 椎动脉行经在寰椎横突孔与椎动脉沟内时 ,在骨性结构上有明显的两个成角 ,即横突孔与椎动脉沟的成角和椎动脉沟绕过侧块的成角 ,椎动脉的这两个成角增加了血液循环的阻力 ,同时在头颈部旋转运动时 ,椎动脉与骨性成角间更加贴近 ,这两个成角与椎 基底动脉供血不足的发生有关。寰椎横突孔后壁较前壁薄 ,此数据可作炒寰椎横突孔后壁切开减压时手术参考依据 相似文献
65.
A 60-year-old Japanese woman was diagnosed at autopsy as having had hereditary hemorrhagic telangiectasia (HHT) associated with systemic hemangiomas. In her repoduction period, premenstrual epistaxis frequently occurred. At the age of 60, the patient died of malignant lymphoma. At autopsy, multiple telangiectatic spots were noted on the face, limbs and trunk. The paraaortic lymph nodes, which were enlarged and irregularly conglomerated, were histologically diagnosed as malignant lymphoma of the diffuse large cell type. Submucosal telangiectatic lesions were found in the gastrointestinal system from the oral cavity to the rectum. Cavernous hemangiomas were present in various visceral organs including the liver, spleen, small and large intestines, rectum, appendix, uterus, and jejunal and colonic mesenteries. There was an arteriovenous fistula in the left lung. Examination of her family pedigree showed that the patient had an autosomal dominant trait of inheritance. The pathogenesis of the systemic visceral hemangiomas observed in this patient was considered to be similar to that of hamartoma. 相似文献
66.
Extrinsic risk factors for compromised blood flow in the vertebral artery: anatomical observations of the transverse foramina from C3 to C7 总被引:2,自引:0,他引:2
Cagnie B Barbaix E Vinck E D'Herde K Cambier D 《Surgical and radiologic anatomy : SRA》2005,27(4):312-316
The vertebral artery (VA) is often involved in the occurrence of complications after spinal manipulative therapy. Due to osteophytes
compressing the VA anteriorly from the uncinate process or posteriorly from the facet complex, the VAs are susceptible to
trauma in the transverse foramina. Such altered anatomical configurations are of major clinical significance, as spinal manipulations
may result in dissection of the VA with serious consequences for the blood supply to the vertebrobasilar region. The purpose
of this study is to describe numerous structural features of the third to seventh cervical vertebrae in order to contribute
to the understanding of pathological conditions related to the VA. The minimal and maximal diameter of 111 transverse foramina
in dry cervical vertebrae were studied. The presence of osteophytes and their influence on the VA were evaluated at the vertebral
body and at the superior and inferior articular facets. The diameter of the transverse foramina increased from C3 to C6, while
the transverse foramina of C7 had the smallest diameter. At all levels the mean dimensions of the left foramina were greater
than those of the right side. Osteophytes from the uncinate process of C5 and C6 vertebrae were found in over 60% of dry vertebrae.
Osteophytes from the zygapophyseal joints were more frequent at C3 and C4 vertebrae. About half of the osteophytes of the
uncinate and of the superior articular process partially covered the transverse foramina. This was less common with those
of the inferior articular facets. Osteophytes covering the transverse foramen force the VAs to meander around these obstructions,
causing narrowing through external compression and are potential sites of trauma to the VAs potentially even leading to dissection.
We strongly advocate that screening protocols for vertebrobasilar insufficiency (VBI) be used prior to any manipulation of
the cervical spine and should include not only extension and rotation but any starting position from which the planned manipulation
will be performed. 相似文献
67.
Infantile hemangioma is a proliferation of beta 4-negative endothelial cells adjacent to HLA-DR-positive cells with dendritic cell morphology 总被引:4,自引:0,他引:4
Although hemangioma is referred as to the most common tumor in infancy, the underlying pathogenetic events and the biologic origin of this benign vascular neoplasm have remained obscure. By using immunohistochemistry on frozen sections of infantile hemangiomas, we show here that proliferating endothelial cells abundantly expressed alpha(v)beta(3) but lacked beta(4) integrins. Instead, regressing and involuting infantile hemangiomas due to treatment with IFN-alpha showed positive staining of beta(4) integrin, which might point to the angiogenic significance of beta(4) integrin in infantile hemangiomas. Moreover, immunofluorescence analysis revealed the existence of HLA-DR(+), mostly CD68(+) and partly DC-SIGN/CD209(+) cells with dendritic cell morphology in the intimate vicinity of hemangiomatous vessels. Such cells were also detected in the dermal microvascular unit in normal skin. The coupled occurrence of vascular structures and perivascular cells that were stained positive with markers of monocyte or macrophage or dendritic cells might suggest that the development of infantile hemangioma is a result of vasculogenesis, that is, the formation of primitive blood vessels from angioblasts, rather than of angiogenesis, that is, the sprouting of capillaries from preexisting vessels. 相似文献
68.
目的初步探讨应用球囊扩张椎体后凸成形术治疗骨质疏松性椎体压缩骨折的临床疗效。方法应用球囊扩张椎体后凸成形术治疗骨质疏松性椎体压缩骨折患者24例28个椎体,并随访4~11个月,平均8个月。结果所有患者手术均获成功,无脊髓神经损伤,病椎疼痛缓解,后凸畸形平均矫正20°,随访期间,疗效满意,无病椎高度丢失。结论应用经皮椎体成形术治疗骨质疏松性椎体压缩骨折能明显改善患者疼痛症状,恢复椎体高度,矫正后凸畸形,是一种安全的微创方法。 相似文献
69.
本实验通过对10只家兔双侧推动脉结扎,观察手术前后脑干听觉诱发电位(BAEPs)的变化[1]。结果发现:动物在推动脉结扎后,随时间延长BAEPs各波的波幅逐渐减压,潜伏期逐渐延长;上述变化持续进行40分钟,以后无大变化。提示:BAEPs可以客观地反映椎基底动脉的供血情况。本项研究为临床用BAEPs诊断椎基底动脉供血不足,提供了一项理论依据。 相似文献
70.
《European journal of medical genetics》2020,63(4):103802
Mabry syndrome is a glycophosphatidylinositol (GPI) deficiency characterized by intellectual disability, distinctive facial features, intractable seizures, and hyperphosphatasia. We expand the phenotypic spectrum of inherited GPI deficiencies with novel bi-allelic phosphatidylinositol glycan anchor biosynthesis class O (PIGO) variants in a neonate who presented with intractable epilepsy and complex gastrointestinal and urogenital malformations. 相似文献