Khadilkar Satish V, Chheda Akash H
Department of Neurology, Grant Govt. Medical College and Sir J. J. Group of Hospitals, Byculla, Mumbai, 400008, India.
Clin Neurol Neurosurg. 2018 May;168:83-90. doi: 10.1016/j.clineuro.2018.03.002. Epub 2018 Mar 5.
Systematic and quantitative evaluation of the plantar reflex has been infrequently studied in the past and can help assess the vexing variables encountered in its elicitation. The objective of this study was to determine the effect of type, pattern and force of stimulation in eliciting an accurate plantar response in patients with pyramidal dysfunction and healthy individuals.
A special instrument was designed to give a predesigned force of stimulus. The plantar surface of foot was divided into nine parts and point and stroke stimulations were studied systematically in pyramidal weakness feet (cases) and healthy control feet (controls) with predefined forces. Results were tabulated and statistically analysed.
Stroke stimulation was superior to point stimulation in eliciting plantar response. There was no significant difference in the responses to the three predefined forces used for stroke stimulations. Sensitivity of Babinski sign was 72.9% and specificity was 100%. In pyramidal weakness feet, extensor responses were significantly elicited from lateral starting stroke patterns (67%) and on moving medially they were replaced by flexor responses (44%). Withdrawal responses increased with the stimulations reaching the distal foot and with the curvilinear component of stimulations. Sensitivity responses (related to the sensitivity of an individual) contaminate the plantar response and occasionally make its interpretation difficult. In subjects with bilateral sensitivity with unilateral disease, knowing the sensitivity pattern on the normal side improved the interpretation of plantar response on the abnormal side.
Based on this study, the optimal method for eliciting Babinski sign accurately is to stroke the lateral aspect of the sole of the foot in a straight line up to mid foot. This should be performed in both feet three times, and if the weakness is unilateral, it should be performed in the normal leg first to aid interpretation of the affected leg.
过去对足底反射的系统定量评估研究较少，它有助于评估引出该反射时遇到的棘手变量。本研究的目的是确定刺激类型、模式和力度对锥体功能障碍患者及健康个体引出准确足底反应的影响。
设计了一种特殊仪器以施加预先设计好的刺激力度。将足底表面分为九个部分，在锥体肌无力足部（病例组）和健康对照足部（对照组）以预先定义的力度系统地研究点刺激和划擦刺激。将结果列表并进行统计分析。
在引出足底反应方面，划擦刺激优于点刺激。用于划擦刺激的三种预先定义力度所引发的反应无显著差异。巴宾斯基征的敏感性为72.9%，特异性为100%。在锥体肌无力足部，从外侧起始的划擦模式显著引出伸肌反应（67%），向内移动时则被屈肌反应取代（44%）。随着刺激到达足部远端以及刺激的曲线部分，撤回反应增加。敏感性反应（与个体的敏感性相关）会干扰足底反应，偶尔会使其难以解读。在单侧疾病导致双侧敏感的受试者中，了解正常侧的敏感模式有助于解读异常侧的足底反应。
基于本研究，准确引出巴宾斯基征的最佳方法是沿直线从足底外侧划擦至足中部。应在双足各进行三次，如果是单侧无力，则应先在正常腿上进行，以辅助解读患侧腿的情况。
