Long-Term Incorporation Properties ofAllograft Bone Chips in Acetabular Reconstruction

同种异体骨移植是仅次于血液成分的第二种最常见的人类移植。植骨是修复骨缺损(如复杂骨折或翻修手术)并确保稳定的基础和足够的临床结果的一种常见方法。在髋关节内假体翻修手术中，髋臼经常会出现较大的骨缺损。根据这些髋臼缺损的三维形态，可以使用不同的骨替代材料和技术，如骨片和结构性骨移植(均为同种异体骨)或合成材料和金属。这些材料和技术通常与骨水泥一起被引入髋臼。目前尚不清楚同种异体骨移植，如结构移植物和同种异体骨片，是仅作为一种重要的填充材料，还是经历了一个连续的结合过程。本项目的目的是分析同种异体骨片的长期定性结合特性。因此，将首次对成功植入的同种异体移植芯片进行系统评估；这为其在翻修关节成形术中的成功临床应用奠定了科学基础。该项目的假设是，同种异体移植芯片：1)成功地改建并被宿主骨结合(结合)；2)随着时间的推移，同种异体骨的结合速度比结构性同种异体移植快，而一定的缺陷尺寸不能超过成功结合的范围。3)未改建的髋关节残骨过度矿化是缺失改建的标志，骨细胞及其小管不能穿透同种异体骨。为此，我们将对至少20个髋关节植入物进行组织学和微形态分析，以进一步阐明宿主骨与同种异体骨之间的整合特性。目前已有25种制剂可供使用，其中至少有20种有望在与临床数据、移植物鉴定和个别切割后用于分析。我在骨科和生物力学系(IOBM)进行骨学研究期间获得的现有科学和方法学专业知识，可以与本项目骨科诊所的临床工作完美地结合起来。

Bone allograft is the second most common human transplant after blood components. The use of bone grafts is a common way to fill the bone defect (e.g. in complex fractures or revision operations) and ensure a stable foundation with sufficient clinical outcome. During revision operations of hip endoprostheses, large bone defects often occur in the acetabulum. Depending on the three-dimensional configuration of these acetabular defects, different bone replacement materials and techniques such as bone chips and structural bone grafts (both allogenic) or synthetic materials and metals are used. These materials and techniques are usually introduced into the acetabulum in combination with bone cement. It has not been conclusively clarified whether allogeneic bone grafts such as structural grafts and allograft chips serve only as avital filling material or are subjected to a continuous incorporation process.The aim of this project is to analyze the long-term qualitative incorporation properties of allograft bone chips. Thus, the first systematic evaluation of successfully implanted allograft chips will be conducted; and this represents the scientific basis for their successful clinical use in revision arthroplasty. The hypothesis of this project is that allograft chips:1) are successfully remodeled and incorporated (incorporated) by the host bone.2) are incorporated faster over time than structural allografts, while a certain defect size must not be exceeded for successful incorporation. 3) Remains that are not remodeled hypermineralize as a sign of the missing remodeling, whereby osteocytes and their canaliculi are not able to penetrate the allograft bone.For this purpose, a total of at least 20 hip explants are to be examined by histological and micro-morphological analysis in order to further clarify the integration properties between host bone and allograft bone. There are already 25 preparations available, of which at least 20 are expected to be used for analysis after comparison with the clinical data, graft identification and individual cutting. The existing scientific and methodological expertise, which I have gained in the course of my osteological research at the Department of Osteology and Biomechanics (IOBM), can be optimally combined with the clinical work in the orthopaedic clinic in this project.