Department of Physiology, All India Institute of Medical Sciences, New Delhi, India.
Division of Trauma Surgery and Critical Care, Jai Prakash Narayan Apex Trauma Centre.
Pain Physician. 2024 Jul;27(5):E589-E595.
BACKGROUND: Phantom limb pain (PLP) is a prevalent and distressing occurrence in 60-80% of individuals who have undergone amputations. Recent research underscores the significance of maladaptive cortical plasticity in the genesis of PLP, emphasizing the importance of targeting cortical areas for therapeutic interventions. Repetitive transcranial magnetic stimulation (rTMS), a noninvasive tool for cortical stimulation, demonstrates effectiveness in treating various chronic pain conditions of neuropathic origin. Nevertheless, there exists a limited body of research investigating the application of rTMS as a therapeutic intervention specifically for managing PLP. Notably, the dorsolateral prefrontal cortex (DLPFC) plays a crucial role in central pain processing, suggesting its potential as a key therapeutic target in PLP treatment. There is a lack of adequate data regarding the effectiveness of DLPFC-targeting rTMS in alleviating the pain experienced by PLP patients. OBJECTIVE: In this study, our aim was to investigate the impact of 10 sessions of DLPFC-targeting rTMS on the pain status of individuals experiencing PLP. STUDY DESIGN: Randomized controlled trial. SETTING: Traumatic amputees reporting to the tertiary care center with PLP. METHODS: The study was approved by the Institute Ethics Committee (IECPG-299/27.04.2022) and registered in the Clinical Trials Registry of India (CTRI/2022/07/043938). Nineteen patients suffering from PLP were recruited and randomized into real or sham rTMS groups. In the real rTMS group, patients received 10 sessions of rTMS at the DLPFC contralateral to the amputation site. The rTMS, administered at 90% of the resting motor threshold (RMT), was delivered as 8 trains of 150 pulses per train at the rate of one Hz and an inter-train interval of 60 seconds. The total number of pulses per session was 1,200. The sham group received 10 sessions of sham rTMS through the perpendicular placement of an rTMS coil over the DLPFC. These sessions lasted for the same duration and included the same sounds as the real group but involved no active stimulation. The patients' pain status was evaluated using the Visual Analog Scale (VAS) at baseline, at the end of each session of real or sham rTMS and at the 15th, 30th, and 60th day after the the completion of real or sham therapy. RESULTS: A significant decrease in VAS scores was noted after 10 sessions of real rTMS that targeted the DLPFC, in contrast to the sham rTMS group. The real rTMS group's reduction in VAS scores also persisted during the follow-up. LIMITATIONS: A few patients had to drop out due to physical restrictions and financial constraints. Consequently, only a small number of individuals were able to complete the study protocol successfully. CONCLUSION: A regimen of 10 sessions of real rTMS of the DLPFC was associated with significant pain relief in patients with PLP, and the effects were sustained for 2 months. Therefore, the present study shows that rTMS of the DLPFC has potential as an effective therapeutic intervention for sustained pain relief in PLP patients.
背景:幻肢痛(PLP)是 60-80%接受截肢手术的个体中普遍存在且令人痛苦的现象。最近的研究强调了皮质适应性不良在 PLP 发病机制中的重要性,强调了针对皮质区域进行治疗干预的重要性。重复经颅磁刺激(rTMS)是一种非侵入性的皮质刺激工具,已被证明对各种源于神经病变的慢性疼痛状况有效。然而,目前关于 rTMS 作为治疗干预措施专门用于管理 PLP 的研究有限。值得注意的是,背外侧前额叶皮质(DLPFC)在中央疼痛处理中起着至关重要的作用,表明其作为 PLP 治疗中关键治疗靶点的潜力。关于针对 DLPFC 的 rTMS 减轻 PLP 患者疼痛的有效性,目前数据不足。
目的:本研究旨在调查 10 次针对 DLPFC 的 rTMS 对 PLP 患者疼痛状况的影响。
研究设计:随机对照试验。
地点:报告有 PLP 的三级护理中心的创伤性截肢者。
方法:该研究得到了机构伦理委员会(IECPG-299/27.04.2022)的批准,并在印度临床试验注册处(CTRI/2022/07/043938)进行了注册。招募了 19 名患有 PLP 的患者,并将他们随机分为真实或假 rTMS 组。在真实 rTMS 组中,患者接受了针对截肢对侧 DLPFC 的 10 次 rTMS。rTMS 以 90%的静息运动阈值(RMT)进行,以 1 Hz 的速率施加 8 个 150 脉冲的训练,每个训练间隔 60 秒。每个疗程的总脉冲数为 1200。假组通过在 DLPFC 上垂直放置 rTMS 线圈接受 10 次假 rTMS。这些疗程持续相同的时间,并包括与真实组相同的声音,但不涉及任何主动刺激。在基线、真实或假 rTMS 每次疗程结束时以及真实或假治疗完成后第 15、30 和 60 天,使用视觉模拟量表(VAS)评估患者的疼痛状况。
结果:与假 rTMS 组相比,针对 DLPFC 的 10 次真实 rTMS 后,VAS 评分显著降低。真实 rTMS 组的 VAS 评分降低在随访期间也持续存在。
局限性:由于身体限制和经济限制,一些患者不得不中途退出。因此,只有少数人能够成功完成研究方案。
结论:10 次针对 DLPFC 的真实 rTMS 与 PLP 患者的显著疼痛缓解相关,并且效果持续了 2 个月。因此,本研究表明,DLPFC 的 rTMS 具有作为 PLP 患者持续缓解疼痛的有效治疗干预措施的潜力。
Sichuan Da Xue Xue Bao Yi Xue Ban. 2022-5