Quantifying Fracture Severity Using a 3-D Puzzle Solving Approach

描述（由申请人提供）：拟议的研究旨在推进评估持续粉碎性关节内骨折患者的创新方法。创伤后骨关节炎（PTOA）是一种具有终生发病率和致残性的晚期并发症，其风险与伴随这些骨折的关节创伤强度有关。目前评估关节损伤严重程度的方法是有限的，不可复制的，并且通常是定性的，阻碍了旨在避免PTOA的新治疗方法的评估。在初始损伤的严重程度可以客观测量之前，它将仍然是阻碍有意义的调查的重大混杂因素。拟议工作的总体目标是建立物理基础，非侵入性技术来量化关节内骨折严重程度。在给定骨折中消耗的机械能的ct衍生测量提供了关节机械损伤的指标。它们没有考虑碎片的定位，或碎片移位和分散，这是反映上睑下垂风险的关键因素，因为这需要目前无法获得分散碎片最初在完整骨中的位置的知识。实际上，推断这些信息需要解决一个三维（3-D）难题，而合适的计算算法最近才开始出现。这种新功能有可能极大地推进粉碎性关节内骨折的评估方式，促进旨在恢复危险关节组织健康的新疗法（主要是生物疗法）的研究。两个具体的目标将追求推进三维解谜方法的使用。具体目标1是在由骨替代物材料加工并包裹在软组织替代物中的试样中产生具有代表性的骨折碎片。碎片的体积和表面数据将从CT扫描中获得（预期的临床用途），碎片在其自发移位/分散的位置，重复的表面数据将从随后的单个碎片的激光扫描中获得（金标准）。根据这些数据，将确定断裂碎片分割的准确性，以及重建已知断裂前试样几何形状的三维解谜精度。具体目标2是从现有的一系列胫骨平台骨折病例中获得3- 5年的结果数据，从而获得三维难题解决方案和相关的骨折严重程度指数。骨折严重程度指标将与临床严重程度排序相关，进而与PTOA的临床发病率相关，并与功能结果测量相关。

DESCRIPTION (provided by applicant): The proposed research aims to advance innovative methods for the evaluation of patients who have sustained comminuted intra-articular fractures. The risk of post-traumatic osteoarthritis (PTOA), a late complication with substantial lifelong morbidity and disability, is related to the intensity of the joint trauma accompanying these fractures. Current methods for assessing the severity of joint injury are limited, irreproducible, and generally qualitative, hindering the evaluation of new treatments aimed at avoiding PTOA. Until the severity of the initial injury can be objectively measured, it will remain a substantial confounder hindering meaningful investigation. A global objective of the proposed work is to establish physically-grounded, non-invasive techniques to quantify intra-articular fracture severity. CT-derived measures of the mechanical energy expended in a given fracture provide an index of the mechanical insult to the joint. They do not account for localization of fragmentation, or fragment displacement and dispersal, critical factors reflecting the risk of PTOA, as this requires presently unavailable knowledge of the positions that the dispersed fragments originally occupied in the intact bone. Deducing this information entails, in effect, solving a three-dimensional (3-D) puzzle, a task for which suitable computational algorithms have recently begun to emerge. This new capability holds the potential to greatly advance the manner in which comminuted intra-articular fractures are assessed, facilitating investigation of new treatments (primarily biologic) aimed at restoring the health of at-risk articular tissues. Two specific aims will be pursued to advance 3-D puzzle solving methods for this use. Specific Aim 1 is to generate representative fracture fragmentation in test specimens machined from a bone surrogate material, and encased in a soft tissue surrogate. Fragment volumetric and surface data will be obtained from CT scans (intended clinical use), with fragments in their spontaneously-displaced/interspersed positions, and duplicate surface data will be obtained from ensuing laser scans of individual fragments (gold standard). Working from these data, the accuracy of fracture fragment segmentation, and 3-D puzzle solution accuracy in reconstructing the known pre- fracture specimen geometry, will be determined. Specific Aim 2 is to obtain 3-D puzzle solutions, and associated fracture severity indices, working from an existing series of tibial plafond fracture cases for which three to five year outcome data will be available. Fracture severity metrics will be correlated with a clinical rank ordering of severity, and in turn with the clinical incidence of PTOA, and with functional outcome measures. PUBLIC HEALTH RELEVANCE: Patients sustaining severe limb trauma in which bones are highly fragmented and the fracture extends into an articular joint such as the ankle or knee, have a generally poor prognosis, with eventual arthritis as a common disabling outcome. Lacking objective measures of fracture severity, surgeons presently rely upon subjective impressions to guide treatment of these patients, hindering progress toward forestalling post-traumatic arthritis. A 3-D puzzle solving approach yields new, objective measures of articular fracture severity, providing a novel framework for statistically robust clinical/translational studies of new treatments to reduce the risk of post-traumatic arthritis.