Katz J
Department of Psychology, Toronto Hospital, Ontario, Canada.
J Neurol Neurosurg Psychiatry. 1992 Sep;55(9):811-21. doi: 10.1136/jnnp.55.9.811.
Phantom limb phenomena were correlated with psychophysiological measures of peripheral sympathetic nervous system activity measured at the amputation stump and contralateral limb. Amputees were assigned to one of three groups depending on whether they reported phantom limb pain, non-painful phantom limb sensations, or no phantom limb at all. Skin conductance and skin temperature were recorded continuously during two 30 minute sessions while subjects continuously monitored and rated the intensity of any phantom limb sensation or pain they experienced. The results from both sessions showed that mean skin temperature was significantly lower at the stump than the contralateral limb in the groups with phantom limb pain and non-painful phantom limb sensations, but not among subjects with no phantom limb at all. In addition, stump skin conductance responses correlated significantly with the intensity of non-painful phantom limb paresthesiae but not other qualities of sensation or pain. Between-limb measures of pressure sensitivity were not significantly different in any group. The results suggest that the presence of a phantom limb, whether painful or painless, is related to the sympathetic-efferent outflow of cutaneous vasoconstrictor fibres in the stump and stump neuromas. The hypothesis of a sympathetic-efferent somatic-afferent mechanism involving both sudomotor and vasoconstrictor fibres is proposed to explain the relationship between stump skin conductance responses and non-painful phantom limb paresthesiae. It is suggested that increases in the intensity of phantom limb paresthesiae follow bursts of sympathetic activity due to neurotransmitter release onto apposing sprouts of large diameter primary afferents located in stump neuromas, and decreases correspond to periods of relative sympathetic inactivity. The results of the study agree with recent suggestions that phantom limb pain is not a unitary syndrome, but a symptom class with each class subserved by different aetiological mechanisms.
幻肢现象与在截肢残端和对侧肢体测量的外周交感神经系统活动的心理生理指标相关。根据截肢者是否报告有幻肢痛、无痛性幻肢感觉或根本没有幻肢，将他们分为三组。在两个30分钟的时间段内持续记录皮肤电导率和皮肤温度，同时受试者持续监测并对他们所经历的任何幻肢感觉或疼痛的强度进行评分。两个时间段的结果均显示，在有幻肢痛和无痛性幻肢感觉的组中，残端的平均皮肤温度显著低于对侧肢体，但在根本没有幻肢的受试者中并非如此。此外，残端皮肤电导率反应与无痛性幻肢感觉异常的强度显著相关，但与其他感觉或疼痛性质无关。任何一组中肢体间压力敏感性测量均无显著差异。结果表明，无论有无疼痛，幻肢的存在都与残端和残端神经瘤中皮肤血管收缩纤维的交感传出流出有关。提出了一种涉及汗腺运动和血管收缩纤维的交感传出-躯体传入机制的假说，以解释残端皮肤电导率反应与无痛性幻肢感觉异常之间的关系。有人认为，幻肢感觉异常强度的增加是由于神经递质释放到位于残端神经瘤中的大直径初级传入纤维的相对应新芽上而引发的交感活动爆发所致，而减少则与相对交感不活动期相对应。该研究结果与最近的观点一致，即幻肢痛不是一种单一的综合征，而是一个症状类别，每个类别由不同的病因机制所支持。
