Höhne Angela, Stark Christian, Brüggemann Gert-Peter
Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Am Sportpark Müngersdorf 6, Köln, Germany.
Clin Biomech (Bristol). 2009 Mar;24(3):308-13. doi: 10.1016/j.clinbiomech.2009.01.001. Epub 2009 Feb 6.
Plantar ulcers are a common and severe complication of the diabetic neuropathic foot. Increased plantar pressures while walking are associated to incidence of plantar ulcer formation in diabetes. There is a strong correlation between the increase in plantar pressures and the severity of peripheral neuropathy. One consequence of peripheral sensory neuropathy is insensitive skin. The influence of reduced plantar sensitivity on changes in plantar pressure distribution is not well understood. The purpose of this study was to identify possible causal dependences between reduced plantar cutaneous sensation and plantar pressure distribution during gait.
Dynamic pressure distribution in gait and sensory perception threshold for pressure touch and vibration (25Hz/200Hz) of the plantar foot were determined pre and post sensory intervention in ten healthy subjects. Cutaneous sensation in both foot soles was experimentally reduced by means of intradermal injections of an anaesthetic solution. This procedure leaves foot and ankle proprioception as well as intrinsic foot muscles unaffected.
The intervention significantly reduced plantar cutaneous sensation to the level of sensory neuropathy. Plantar pressure and force variables, contact times for the entire foot and for the plantar foot regions were not influenced significantly.
Experimentally reducing plantar cutaneous sensation causes no changes in plantar pressure distribution while walking. Our findings suggest that in the diabetic neuropathic foot insensitive plantar skin due to peripheral sensory neuropathy may be not a decisive factor for altering plantar pressures. This is underpinning the importance of concomitant affection of different systems secondary to diabetic peripheral neuropathy.
足底溃疡是糖尿病神经病变足常见且严重的并发症。步行时足底压力增加与糖尿病患者足底溃疡形成的发生率相关。足底压力增加与周围神经病变的严重程度之间存在密切关联。周围感觉神经病变的一个后果是皮肤感觉减退。足底感觉减退对足底压力分布变化的影响尚不清楚。本研究的目的是确定步态期间足底皮肤感觉减退与足底压力分布之间可能存在的因果关系。
对10名健康受试者在感觉干预前后测定其步态中的动态压力分布以及足底压力触觉和振动（25Hz/200Hz）的感觉阈值。通过皮内注射麻醉溶液实验性降低双足底的皮肤感觉。该操作不影响足部和踝关节本体感觉以及足部固有肌肉。
干预显著降低了足底皮肤感觉至感觉神经病变水平。足底压力和力变量、整个足部及足底区域的接触时间均未受到显著影响。
实验性降低足底皮肤感觉不会导致步行时足底压力分布发生变化。我们的研究结果表明，在糖尿病神经病变足中，由于周围感觉神经病变导致的足底皮肤感觉减退可能不是改变足底压力的决定性因素。这强调了糖尿病周围神经病变继发不同系统同时受累的重要性。
