Abstract：
The importance of the transverse tarsal arch (TTA) has recently been extensively reevaluated and has even been considered to play a greater role in foot stability than the medial longitudinal arch (MLA). However, the relevance of this observation in the context of common clinical foot disorders, such as progressive collapsing foot deformity (PCFD), has not yet been fully clarified. In this biomechanical study, we examined ten pairs of human cadaveric feet by serial weight-bearing cone-beam computed tomography under controlled loading using a custom-designed testing machine. The MLA and TTA were transected separately, alternating the order in two study groups. A semiautomated three-dimensional evaluation of their influence on three components of PCFD, namely collapse of the longitudinal arch (sagittal Meary\'s angle), hindfoot alignment (sagittal talocalcaneal angle), and forefoot abduction (axial Meary\'s angle), was performed. Both arches had a relevant effect on collapse of the longitudinal arch, however the effect of transecting the MLA was stronger compared to the TTA (sagittal Meary\'s angle, 7.4° (95%CI 3.8° to 11.0°) vs. 3.2° (95%CI 0.5° to 5.9°); p = 0.021). Both arches had an equally pronounced effect on forefoot abduction (axial Meary\'s angle, 4.6° (95%CI 2.0° to 7.1°) vs. 3.0° (95%CI 0.6° to 5.3°); p = 0.239). Neither arch showed a consistent effect on hindfoot alignment. In conclusion, weakness of the TTA has a decisive influence on radiological components of PCFD, but not greater than that of the MLA. Our findings contribute to a deeper understanding and further development of treatment concepts for flatfoot disorders.
摘要：
最近，对横骨弓（TTA）的重要性进行了广泛的重新评估，甚至被认为在脚的稳定性方面比内侧纵向弓（MLA）发挥更大的作用。然而,在常见的临床足部疾病的背景下，这一观察的相关性，如进行性塌陷性足部畸形（PCFD），尚未完全澄清。在这项生物力学研究中，我们使用定制设计的试验机在受控载荷下，通过连续的负重锥形束计算机断层扫描检查了十对人类尸体脚。MLA和TTA被分别横切,在两个研究组中交替顺序。半自动三维评估它们对PCFD三个组件的影响，即纵向拱的塌陷(矢状米里角)，后足对齐（矢状角距骨角度），和前足外展（轴向米里角），已执行。两个拱门都对纵向拱门的坍塌有相关影响，然而，与TTA相比，横切MLA的效果更强(矢状米里角度，7.4°(95CI3.8°至11.0°)与3.2°（95CI0.5°至5.9°）；p=0.021）。两个牙弓对前足外展有同样显著的影响(轴向米里角，4.6°(95CI2.0°至7.1°)与3.0°（95CI0.6°至5.3°）；p=0.239）。两个足弓对后脚对齐均未显示一致的影响。总之,TTA的弱点对PCFD的放射成分有决定性的影响，但不超过MLA。我们的发现有助于更深入地了解和进一步发展扁平足疾病的治疗概念。
