Torebjörk H E, Ochoa J L, Schady W
Department of Clinical Neurophysiology, University Hospital, S-751 85 UppsalaSweden Division of Neurology, Dartmouth Medical School, Hanover, NH 03756 U.S.A.
Pain. 1984 Feb;18(2):145-156. doi: 10.1016/0304-3959(84)90882-0.
Microelectrode recordings were obtained from 118 cutaneous and 26 muscle fascicles in the intact median nerves of healthy human subjects. The exploring electrodes were also used for painful electrical stimulation of the identified fascicles. Cutaneous pain was accurately projected to fields within the median innervation territory. Deep pain was projected to muscles innervated by the median nerve, but in 7 experiments it was also segmentally referred to muscles in the ipsilateral upper arm, axilla or chest. Reaction time measurements indicated that referred pain was conveyed by afferent group III fibres from muscle, but did not exclude a possible contribution by group IV fibres. Referred pain was influenced by temporal and spatial summation of the afferent inflow. The magnitude of referred pain was positively correlated to the stimulation frequency of deep nociceptive fibres. The results from this study on experimentally induced pain confirm clinical observations of proximal referral of pain in patients with median nerve entrapment, and prompt consideration of possible involvement of nerve fascicles supplying deep structures in the forearm or hand in the differential diagnosis of pain in the chest and upper arm.
在健康人体正中神经完整的情况下，从118个皮区和26个肌束获取了微电极记录。探测电极也用于对已识别肌束进行疼痛性电刺激。皮肤痛被精确投射到正中神经支配区域内的部位。深部痛被投射到由正中神经支配的肌肉，但在7次实验中，它也被节段性地牵涉到同侧上臂、腋窝或胸部的肌肉。反应时间测量表明，牵涉痛由来自肌肉的Ⅲ类传入纤维传导，但不排除Ⅳ类纤维可能也有作用。牵涉痛受传入冲动的时间和空间总和的影响。牵涉痛的程度与深部伤害性纤维的刺激频率呈正相关。这项关于实验性诱发疼痛的研究结果证实了正中神经卡压患者疼痛向近端牵涉的临床观察结果，并促使在对胸部和上臂疼痛进行鉴别诊断时，考虑在前臂或手部供应深部结构的神经束可能受累的情况。
