Department of Rehabilitation for the Movement Functions, Research Institute, National Rehabilitation Center for Persons with Disability, Tokorozawa, Saitama, Japan.
PLoS One. 2013 Jul 25;8(7):e69324. doi: 10.1371/journal.pone.0069324. Print 2013.
To test whether the phantom limb awareness could be altered by observing mirror reflection-induced visual feedback (MVF) in unilateral forearm amputees.
Ten unilateral forearm amputees were asked to perform bilateral (intact and phantom) synchronous wrist motions with and without MVF. During wrist motion, electromyographic activities in the extensor digitorum longus (EDL) and flexor carpi radialis muscles (FCR) were recorded with bipolar electrodes. Degree of wrist range of motion (ROM) was also recorded by electrogoniometry attached to the wrist joint of intact side. Subjects were asked to answer the degree of attainment of phantom limb motion using a visual analog scale (VAS: ranging from 0 (hard) to 10 (easy)).
VAS and ROM were significantly increased by utilizing MVF, and the extent of an enhancement of the VAS and wrist ROM was positively correlated (r = 0.72, p<0.05). Although FCR EMG activity also showed significant enhancement by MVF, this was not correlated with the changes of VAS and ROM. Interestingly, while we found negative correlation between EDL EMG activity and wrist ROM, MVF generally affected to be increasing both EDL EMG and ROM.
Although there was larger extent of variability in the effect of MVF on phantom limb awareness, MVF has a potential to enhance phantom limb awareness, in case those who has a difficulty for the phantom limb motion. The present result suggests that the motor command to the missing limb can be re-activated by an appropriate therapeutic strategy such as mirror therapy.
测试单侧前臂截肢者通过观察镜像反射诱导的视觉反馈（MVF）是否可以改变幻肢意识。
要求 10 名单侧前臂截肢者在有和没有 MVF 的情况下进行双侧（健侧和幻侧）同步腕关节运动。在腕关节运动过程中，使用双极电极记录伸指长肌（EDL）和桡侧腕屈肌（FCR）的肌电图活动。通过附着在健侧腕关节的电子测角计记录腕关节活动度（ROM）的程度。要求受试者使用视觉模拟量表（VAS：范围从 0（困难）到 10（容易））回答幻肢运动的完成程度。
利用 MVF 可显著增加 VAS 和 ROM，并且 VAS 和腕 ROM 的增强程度呈正相关（r = 0.72，p<0.05）。尽管 MVF 也显著增强了 FCR 肌电图活动，但与 VAS 和 ROM 的变化无关。有趣的是，虽然我们发现 EDL 肌电图活动与腕 ROM 之间存在负相关，但 MVF 通常会影响 EDL 肌电图和 ROM 的增加。
尽管 MVF 对幻肢意识的影响程度存在较大的可变性，但 MVF 有可能增强幻肢意识，特别是对于那些难以进行幻肢运动的患者。目前的结果表明，通过适当的治疗策略，如镜像治疗，可以重新激活对缺失肢体的运动指令。
