McGill M, Molyneaux L, Yue D K
Diabetes Centre, Royal Prince Alfred Hospital, Camperdown, NSW, Australia.
Diabet Med. 1998 Jul;15(7):615-7. doi: 10.1002/(SICI)1096-9136(199807)15:7<615::AID-DIA641>3.0.CO;2-P.
The Semmes-Weinstein monofilament has been developed for the detection of patients at risk of neuropathic ulceration. In this study we evaluated how the physical characteristics of the monofilaments can impact on their performance. Commercially purchased monofilaments from the Hansen's Disease Center (HDC) and a batch produced 'in-house' (RPAH) were calibrated using a Mettler Balance. To assess the effects of varying lengths on buckling force, the monofilaments were tested repeatedly while the length of the filament was reduced stepwise from 4.1 to 3.1 cm. The correct length of the monofilament to generate a buckling force of 10 g was also determined theoretically by applying the Euler's Buckling Equation. Results showed neither batch of monofilaments buckled at a strength of 10 g (HDC 6.8 g, CI 5.7-7.9, and RPAH 7.2 g, CI 7.1-7.3). In addition HDC showed a wide interfilament variation range, 4.1-10.3 g with CV 29% versus corresponding figures of range 7.1-7.9 g, CV 4.9% for the RPAH monofilaments. As predicted by Euler's Buckling Theory, buckling force can be increased by reducing the length of the filament. These results demonstrate that the physical characteristics of the monofilament are important determinants of buckling force and are not necessarily uniform in commercial filaments. The clinical relevance of variance in buckling force remains to be determined.
Semmes-Weinstein单丝已被开发用于检测有神经性溃疡风险的患者。在本研究中，我们评估了单丝的物理特性如何影响其性能。使用梅特勒天平对从汉森病中心（HDC）商业购买的单丝和一批“内部”生产（RPAH）的单丝进行校准。为了评估不同长度对屈曲力的影响，在单丝长度从4.1厘米逐步减少到3.1厘米的过程中，对单丝进行反复测试。通过应用欧拉屈曲方程，理论上也确定了产生10克屈曲力的单丝正确长度。结果显示，两批单丝均未在10克强度下发生屈曲（HDC为6.8克，置信区间5.7 - 7.9，RPAH为7.2克，置信区间7.1 - 7.3）。此外，HDC显示出较大的丝间变化范围，为4.1 - 10.3克，变异系数为29%，而RPAH单丝的相应范围为7.1 - 7.9克，变异系数为4.9%。正如欧拉屈曲理论所预测的，通过缩短单丝长度可以增加屈曲力。这些结果表明，单丝的物理特性是屈曲力的重要决定因素，并且商业单丝不一定是均匀的。屈曲力差异的临床相关性仍有待确定。
