Adams Daniel L, Economides John R, Jocson Cristina M, Horton Jonathan C
Program in Neuroscience, University of California, San Francisco, San Francisco, California 94143-0730, USA.
J Neurophysiol. 2007 Aug;98(2):993-1001. doi: 10.1152/jn.00102.2007. Epub 2007 May 23.
Many neurophysiological experiments involving monkeys require that the head be stabilized while the animal performs a task. Often a post is attached to the skull to accomplish this goal, using a headcap formed from dental acrylic. We describe a new headpost, developed by refinement of several prototypes, and supply an AutoCAD file to aid in machine shop production. This headpost is fabricated from a single piece of commercially pure titanium. It has a footplate consisting of four limbs arranged in the configuration of a "K." These are bent during surgery to match the curvature of the skull and attached with specialized titanium bone screws. Headposts were implanted in seven rhesus monkeys ranging in age from 2 yr to adult. None has been rejected after up to 17 mo of regular use. They require little or no daily toilette and create only a 0.80-cm(2) defect in the scalp. Computed tomography after implantation showed that the skull undergoes remodeling to embed the footplate in bone. This finding was confirmed by necropsy in two subjects. The outer table of the skull had grown over the titanium footplate, whereas the inner table had thickened to bury the tips of the titanium screws. The remarkable strength of the skull/implant bond was demonstrated by applying increasing amounts of torque to the headpost. At 26.3 Nm, the headpost tore from its metal footplate, but no screws came loose. The excellent performance of this implant is explained by integration of biocompatible titanium into remodeled bone tissue. The headpost is simpler to implant, more securely anchored, easier to maintain, and less obtrusive than devices attached with acrylic.
许多涉及猴子的神经生理学实验要求在动物执行任务时稳定其头部。通常会在头骨上附着一个柱子来实现这一目标，使用由牙科丙烯酸制成的头帽。我们描述了一种通过改进多个原型开发的新型头柱，并提供了一个AutoCAD文件以协助机械加工生产。这种头柱由单件商业纯钛制成。它有一个脚板，由四个呈“K”形排列的分支组成。这些分支在手术过程中弯曲以匹配头骨的曲率，并使用专门的钛骨螺钉固定。对头柱植入了7只年龄从2岁到成年的恒河猴。在长达17个月的常规使用后，没有一个被排斥。它们几乎不需要日常护理，并且在头皮上只造成0.80平方厘米的缺损。植入后的计算机断层扫描显示，头骨会进行重塑，将脚板嵌入骨中。这一发现在两只受试动物的尸检中得到了证实。头骨的外板在钛脚板上生长，而内板增厚以掩埋钛螺钉的尖端。通过对头柱施加越来越大的扭矩，证明了头骨/植入物结合的非凡强度。在26.3牛米的扭矩下，头柱从其金属脚板上撕裂，但没有螺钉松动。这种植入物的优异性能可以通过生物相容性钛融入重塑的骨组织来解释。与用丙烯酸附着的装置相比，这种头柱植入更简单、锚固更牢固、维护更容易且更不显眼。
