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21.
We describe a firm, effective suture-tying method using a tensioner for reattaching tibial avulsion fractures of the anterior cruciate ligament. Our simple method achieves strong, firm reattachment of the fracture. In addition, it prevents fixation loosening during suture tying effectively. Since pullout repair using nonabsorbable sutures is commonly used to fix various avulsion fractures, the tensioner helps attain strong, firm reattachment of avulsion fractures simply and effectively.  相似文献   
22.
目的 观察等距和非等距前交叉韧带(anterior cruciate ligament,ACL)重建对膝关节功能的影响。方法 采用新鲜尸体观察等距ACL的解剖结构,在尸体和模型上重建等距和非等距ACL,分别观察重建后ACL长度和胫骨平台表面压强的变化。结果 等距ACL的重建在膝关节的全范围活动中长度的变化值最小,胫骨平台所受的压强也最小。结论 只有等距的ACI。的重建才能恢复膝关节的正常生理功能,而非等距重建的ACL会造成膝关节的不稳定(或活动受限),或者使膝关节表面的压强增加。  相似文献   
23.
颈前路植骨钢板内固定治疗创伤性枢椎前滑移   总被引:1,自引:1,他引:0  
目的 评价C2、C3椎体间植骨、钢板内固定治疗创伤性枢椎前滑移的临床价值。方法 8例创伤性枢椎前滑移患行颈前路手术复位、椎间盘切除减压、自体髂骨植骨、钢板内固定术,平均随访1年,观察患术后颈椎生理高度、曲度重建和颈椎稳定性、运动情况。结果 8例患均获得完全的枢椎复位,C2、C3椎体在术后16周达到骨性融合,颈椎生理高度、曲度得以重建,旋转、屈伸功能良好,无钢板螺钉并发症。结论 颈前路钢板内固定是治疗创伤性枢椎前滑移的有效方法。  相似文献   
24.
By use of a double-labeling immunofluorescence method with a confocal laser scanning microscope, we have examined whether a calcium-binding protein, calretinin, is localized in magnocellular oxytocin and vasopressin neurons of the rat hypothalamus. In the supraoptic nucleus, all oxytocin-labeled cells were stained for calretinin. However, in the magnocellular part of the paraventricular nucleus, almost all oxytocin-stained cells were devoid of calretinin immunoreactivity. All vasopressin-positive cells of both the supraoptic nucleus and the magnocellular part of the paraventricular nucleus lacked calretinin immunoreactivity. No calretinin immunoreactivity was found in oxytocin-labeled cells of the the anterior commissural nucleus or in vasopressin-labeled cells of the suprachiasmatic nucleus. We previously showed that another calcium-binding protein, calbindin-D28k, was localized in magnocellular oxytocin neurons of the supraoptic nucleus but not in those of the paraventricular nucleus. These findings suggest that, in general, magnocellular oxytocin neurons of the supraoptic nucleus and those of the paraventricular nucleus can be chemically distinguished, that is, the former contain both calretinin and calbindin-D28k but the latter lack the two calcium-binding proteins.  相似文献   
25.
An ultrastructural study was undertaken concerning morphological changes within the autografted patellar tendon (PT) after being transplanted to the anterior cruciate ligament (ACL) in mongrel dogs. After 4 weeks, the arrangements of both large and small collagen fibrils in the PT graft became disordered, and the number of inflammatory cells increased. However, the same PT grafts revealed postsurgical signs of newly-produced collagen fibrils around activated fibroblasts at 12 to 24 weeks. At 52 weeks after the transplantation, small collagen fibrils increased in both number and density, showing a remarkable morphological similarity to the collagen fibrils of normal ACL. These data indicate that the characteristics of the PT graft eventually resemble those of a normal ACL. This paper was presented in part at the Combined Meeting of the Orthopedic Research Societies of the USA, Japan and Canada in Banff, Alberta, Canada, October, 1991.  相似文献   
26.
We report on a case of idiopathic uveal effusion syndrome complicated by AION. To our knowledge such an association hasn't been previously described. We suggest that scleral thickening caused obstruction of vortex veins followed by uveal effusion and compression of posterior ciliary arteries within their intrascleral tract, leading to AION. Nevertheless it can't be excluded that AION was the result of mechanical compression on ciliary vessels of optic disc by choroidal detachment.  相似文献   
27.
Summary The sensitivity of the cochlea is dependent upon maintenance of a delicate homeostatic environment. One mechanism which participates in providing this environment is the autoregulation of cochlear blood flow. This autoregulation is ensured through the interaction of sympathetic, peptidergic and hemodynamic mechanisms. The current study demonstrates an adaptation that also participates in cochlear blood flow autoregulation. Specifically, an anterior inferior cerebellar arterial network is described and the relative contributions of each of its vessels to total cochlear blood flow is measured using laser Doppler flowmetry. The results show that each collateral vessel contributes to the blood supply of the cochlea and that reperfusion is accompanied by hyperemia. These findings suggest an adaptation that provides stable blood flow through redundancy and compensatory potential. Additionally, these observations have implications for experimental models of ischemia.  相似文献   
28.
1980年12月至1993年12月,我科经前方入路治疗颈椎病并获随访183例,其中37例(20.2%)术后恢复不满意,JOA恢复率小于60%。根据主诉与症状,我们把这些病人分成4组。(1)术后症状立即加重,1年内仍无改善者4例。(2)术后症状无明显改善,1年后仍无进步者11例。(3)术后症状减轻,但经过一段时间后,原症状又复出现者8例。(4)双下肢症状好转,但又出现新的上肢症状或上肢原症状加重者14例。结合术后X线、CT、MRI和椎管造影等检查所见,我们将发现的主要问题归纳为手术操作、病情发展演变、原有胸腰椎病和脊髓受压变性等情况。本文对以上发生的问题进行了分析,提出在以后的手术中应特别注意的事项。  相似文献   
29.
目的 通过107例胸腰椎骨折伴脊髓损伤病例的治疗,探讨前、后路手术适应证的选择。方法 31例经前路减压植骨,采用Z-Plate等内固定。76例经后路采用短节段椎弓根钉内固定。结果 两组均获得了满意的疗效。结论 选择前或后路手术,应综合考虑脊髓损伤程度、手术时机与技巧、骨折的部位、骨折类型和影像结果等,才能确实做到减压、恢复脊柱序列和坚强固定的目的。  相似文献   
30.
Transesophageal echocardiography was conducted to determine the systolic pattern of the anterior mitral leaflet in patients with flat chest, and to differentiate it from that associated with mitral valve prolapse. The fronto-sagittal index (an index of chest flattening) was determined in 50 subjects using chest radiographs, and was used to classify them into a flat chest group (index < 0.38, n = 28) and a normal chest group (index ≥ 0.38, n = 22). We then used transesophageal echocardiography to examine the anterior leaflet in these subjects. A significant positive correlation was observed between the fronto-sagittal index and the short-to long-axis diameter ratio of the left ventricle in all patients. These parameters, and the left atrial dimension were lower in the flat than the normal chest group. The clear zone area of the anterior leaflet during mid-to late-systole was significantly larger in the flat chest group. However, no intergroup differences existed in the rough zone area of the anterior leaflet or in the middle scallop area of the posterior leaflet. Mitral regurgitation was observed in 20 and 12 subjects in the flat and normal chest groups, respectively. The maximum mitral regurgitant area did not differ between the two groups. The clear zone area of the anterior leaflet increased significantly following inhalation of amyl nitrite in 22 subjects of both groups, but the other areas did not increase. The mitral regurgitant area decreased or disappeared after amyl nitrite at a similar rate in each group. Thus, the decrease in the antero-posterior dimension of the thorax in subjects with flat chest affects the systolic pattern of the clear zone of the anterior leaflet more than that of the rough zone of the anterior leaflet or the posterior leaflet. This systolic pattern in such patients differs from that associated with mitral valve prolapse.  相似文献   
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