Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada.
Department of Clinical Neuroscience, University of Calgary, Calgary, Alberta, Canada.
PLoS One. 2018 Jun 1;13(6):e0197557. doi: 10.1371/journal.pone.0197557. eCollection 2018.
To examine tactile sensitivity in the leg and foot sole of below-knee amputees (diabetic n = 3, traumatic n = 1), and healthy control subjects (n = 4), and examine the association between sensation and balance.
Vibration perception threshold (VPT; 3, 40, 250Hz) and monofilaments (MF) were used to examine vibration and light touch sensitivity on the intact limb, residual limb, and homologous locations on controls. A functional reach test was performed to assess functional balance.
Tactile sensitivity was lower for diabetic amputee subjects compared to age matched controls for both VPT and MF; which was expected due to presence of diabetic peripheral neuropathy. In contrast, the traumatic amputee participant showed increased sensitivity for VPT at 40Hz and 250Hz vibration in both the intact and residual limbs compared to controls. Amputees with lower tactile sensitivity had shorter reach distances compared to those with higher sensitivity.
Changes in tactile sensitivity in the residual limb of trans-tibial amputees may have implications for the interaction between the amputee and the prosthetic device. The decreased skin sensitivity observed in the residual limb of subjects with diabetes is of concern as changes in skin sensitivity may be important in 1) identification/prevention of excessive pressure and 2) for functional stability. Interestingly, we saw increased residual limb skin sensitivity in the individual with the traumatic amputation. Although not measured directly in the present study, this increase in tactile sensitivity may be related to cortical reorganisation, which is known to occur following amputation, and would support similar findings observed in upper limb amputees.
检查膝下截肢者（糖尿病 n = 3，创伤性 n = 1）和健康对照组（n = 4）腿部和足底的触觉敏感性，并探讨感觉与平衡之间的关系。
使用振动感觉阈值（VPT；3、40、250Hz）和单丝纤维（MF）检查未受损肢体、残肢和对照组同源部位的振动和轻触觉。进行功能伸展测试以评估功能性平衡。
与年龄匹配的对照组相比，糖尿病截肢患者的 VPT 和 MF 触觉敏感性均较低；这是由于存在糖尿病周围神经病变。相比之下，创伤性截肢患者在未受损和残肢的 40Hz 和 250Hz 振动下的 VPT 敏感性均高于对照组。触觉敏感性较低的截肢者的伸展距离比敏感性较高的截肢者短。
经胫骨截肢者残肢触觉敏感性的变化可能会影响截肢者与假肢装置之间的相互作用。在糖尿病患者的残肢中观察到的皮肤敏感性降低令人担忧，因为皮肤敏感性的变化可能在以下两个方面很重要：1）识别/预防过度压力，2）功能稳定性。有趣的是，我们在创伤性截肢患者中看到了残肢皮肤敏感性的增加。尽管本研究未直接测量，但这种触觉敏感性的增加可能与皮质重组有关，这是已知的截肢后发生的现象，这将支持在上肢截肢者中观察到的类似发现。
