Hsu Chih-Chin, Tsai Wen-Chung, Hsiao Tzu-Yo, Tseng Fen-Yu, Shau Yio-Wha, Wang Chung-Li, Lin Shih-Chieh
Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Keelung, Taiwan.
Clin Biomech (Bristol). 2009 Oct;24(8):682-6. doi: 10.1016/j.clinbiomech.2009.06.005. Epub 2009 Jul 19.
The study attempted to highlight the differences of mechanical properties in microchambers and macrochambers between patients with type 2 diabetes mellitus and age-matched healthy volunteers.
A total of 29 heels in 18 diabetic patients and 28 heels in 16 age-matched healthy participants were examined by a loading device consisting of a 10-MHz compact linear-array ultrasound transducer, a Plexiglas cylinder, and a load cell. Subjects in both groups were on average about 55 years old with a body mass index of approximately 25 kg/m(2). A stepping motor was used to progressively load the transducer on the tested heels at a velocity of 6mm/s from zero to the maximum stress of 78 kPa. Unloaded thickness, strain, and elastic modulus in microchambers, macrochambers and heel pads were measured.
Microchambers strain in diabetic patients was significantly greater than that in healthy subjects (0.291 (SD 0.14) vs. 0.104 (SD 0.057); P<0.001). Macrochambers strain in diabetic patients was significantly less than that in healthy subjects (0.355 (SD 0.098) vs. 0.450 (SD 0.092); P=0.001). Microchambers stiffness in diabetic patients was significantly less than that in healthy persons (393 (SD 371)kPa vs. 1140 (SD 931)kPa; P<0.001). Macrochambers stiffness in diabetic patients was significantly greater than that in healthy persons (239 (SD 77)kPa vs. 181 (SD 42)kPa; P=0.001).
Heel pad tissue properties are altered heterogeneously in people with diabetes. Increased macrochambers but decreased microchambers stiffness may cause diminished cushioning capacities in diabetic heels.
本研究旨在突出2型糖尿病患者与年龄匹配的健康志愿者在微腔和宏腔力学性能上的差异。
使用由10兆赫紧凑型线性阵列超声换能器、有机玻璃圆柱体和测力传感器组成的加载装置，对18例糖尿病患者的29只足跟以及16名年龄匹配的健康参与者的28只足跟进行检查。两组受试者平均年龄约55岁，体重指数约为25kg/m²。使用步进电机以6mm/s的速度将换能器逐步加载到受试足跟，从零加载到最大应力78kPa。测量微腔、宏腔和足跟垫的未加载厚度、应变和弹性模量。
糖尿病患者微腔应变显著高于健康受试者（0.291（标准差0.14）对0.104（标准差0.057）；P<0.001）。糖尿病患者宏腔应变显著低于健康受试者（0.355（标准差0.098）对0.450（标准差0.092）；P=0.001）。糖尿病患者微腔刚度显著低于健康人（393（标准差371）kPa对1140（标准差931）kPa；P<0.001）。糖尿病患者宏腔刚度显著高于健康人（239（标准差77）kPa对181（标准差42）kPa；P=0.001）。
糖尿病患者足跟垫组织特性存在异质性改变。宏腔刚度增加但微腔刚度降低可能导致糖尿病足跟缓冲能力下降。
