INTERFACE MECHANICS, MATERIALS AND TISSUE RESPONSE

描述（由申请人提供）：本申请的广泛、长期目标是开发预测和治疗每日和长期残肢形状变化的方法，以减少下肢截肢者皮肤破裂的发生。具体目的是评估经胫骨截肢者在不同的套骨修饰治疗下的界面应力稳定性，这些治疗旨在克服由形状变化引起的配合问题。进一步的目标是更好地了解昼夜和长期形状变化的来源，并将其与残肢液体输送和其他可在临床评估中评估的患者组织特征联系起来。为了解决这一问题，在控制体积的液体填充细胞、厚度均匀的插入物和粘贴在软组织丢失位置的材料贴片，与现有的界面压力和剪切应力测量系统以及定制的高分辨率残肢扫描仪一起使用。在残肢形态发生变化的情况下，研究人员确定了这些处理在昼夜和12个月间隔内保持界面应力一致的能力，并将其与未处理的处理进行了比较。预计对于日波动：充液细胞比其他处理表现更好；保持界面应力一致的最佳细胞液体积与残肢体积损失相匹配；利用液体细胞，远端肢体在窝内的运动与最初的配合是相同的。对于长期的变化，预计需要在凹槽内部粘贴局部材料贴片和充满液体的细胞来稳定界面应力。为了更好地了解残肢形状变化的生理来源，我们测量了残肢细胞外含水量、液体运输和组织含量。预计昼夜收缩反映了一天中细胞外水的缓慢损失。然而，长期收缩预计会反映肌肉组织含量的减少。这个项目与健康的关系是改善截肢者的生活质量。预测和克服残肢形态改变的不利影响并最终预防软组织破坏的方法的发展将有助于预防截肢人群的继发性残疾和发病率。

DESCRIPTION (provided by applicant): The broad, long-term objectives of this application are to develop methods to predict and treat diurnal and long-term residual limb shape changes to reduce the occurrence of skin breakdown in persons with lower-limb amputation. The specific aims are to assess interface-stress stability in trans-tibial amputee subjects under different socket-modification treatments designed to overcome fit problems induced by shape changes. A further aim is to better understand the sources of diurnal and long-term shape changes and to correlate them with residual limb fluid transport and other patient tissue characteristics that can be assessed in clinical evaluation. To address the aims fluid-filled cells at controlled volumes, a uniform-thickness insert, and material patches affixed to the inside of the socket at locations of soft-tissue loss are used with an existing interface pressure and shear stress measurement system and a custom, high-resolution, residual-limb scanner. The capabilities of the treatments to keep interface stresses consistent over both diurnal and 12-mo intervals, despite changes in residual limb shape, are determined and compared with no treatment. It is expected that for diurnal fluctuations: the fluid-filled cells perform better than the other treatments; the optimal cell fluid volume to keep interface stresses consistent matches the residual limb volume loss; and using the fluid cells distal limb movement in the socket is identical to that of the initial fit. For long-term changes, it is expected that both local material patches affixed to the inside of the socket and the fluid-filled cells are needed to stabilize interface stresses. To better understand the physiologic sources of residual limb shape change, residual limb extracellular water content, fluid transport, and tissue content are measured on a population of trans-tibial amputee subjects. It is expected that diurnal shrinkage reflects a slow loss of extracellular water over the course of the day. Long-term shrinkage, however, is expected to reflect a reduction in muscle tissue content. The health relatedness of this project is improvement in the quality of life of persons with amputated limbs. The development of methods to predict and overcome the detrimental effects of residual limb shape change and ultimately prevent soft-tissue breakdown will help to prevent secondary disability and morbidity in the amputee population.