Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital and Massachusetts General Hospital, Charlestown, Massachusetts, U.S.A.
Department of Neuropsychology, Institute of Psychology, University of Zurich, Zurich, Switzerland.
Pain Pract. 2020 Jul;20(6):578-587. doi: 10.1111/papr.12881. Epub 2020 Apr 8.
The exact mechanisms underlying the development and maintenance of phantom limb pain (PLP) are still unclear. This study aimed to identify the factors affecting pain intensity in patients with chronic, lower limb, traumatic PLP.
This is a cross-sectional analysis of patients with PLP. We assessed amputation-related and pain-related clinical and demographic variables. We used univariate and multivariate models to evaluate the associated factors modulating PLP and residual limb pain (RLP) intensity.
We included 71 unilateral traumatic lower limb amputees. Results showed that (1) amputation-related perceptions were experienced by a large majority of the patients with chronic PLP (sensations: 90.1%, n = 64; residual pain: 81.7%, n = 58); (2) PLP intensity has 2 significant protective factors (phantom limb movement and having effective treatment for PLP previously) and 2 significant risk factors (phantom limb sensation intensity and age); and (3) on the other hand, for RLP, risk factors are different: presence of pain before amputation and level of amputation (in addition to the same protective factors).
These results suggest different neurobiological mechanisms to explain PLP and RLP intensity. While PLP risk factors seem to be related to maladaptive plasticity, since phantom sensation and older age are associated with more pain, RLP risk factors seem to have components leading to neuropathic pain, such as the amount of neural lesion and previous history of chronic pain. Interestingly, the phantom movement appears to be protective for both phenomena.
幻肢痛（PLP）发展和维持的确切机制仍不清楚。本研究旨在确定影响慢性下肢创伤性 PLP 患者疼痛强度的因素。
这是一项对 PLP 患者的横断面分析。我们评估了与截肢和疼痛相关的临床和人口统计学变量。我们使用单变量和多变量模型来评估调节 PLP 和残肢痛（RLP）强度的相关因素。
我们纳入了 71 名单侧下肢创伤性截肢患者。结果表明：（1）大多数慢性 PLP 患者都经历了与截肢相关的感知（感觉：90.1%，n=64；残肢痛：81.7%，n=58）；（2）PLP 强度有 2 个显著的保护因素（幻肢运动和之前对 PLP 的有效治疗）和 2 个显著的风险因素（幻肢感觉强度和年龄）；（3）另一方面，对于 RLP，风险因素不同：截肢前存在疼痛和截肢水平（除了相同的保护因素外）。
这些结果表明，不同的神经生物学机制可以解释 PLP 和 RLP 强度。虽然 PLP 的风险因素似乎与适应性可塑性有关，因为幻肢感觉和年龄较大与更多的疼痛有关，但 RLP 的风险因素似乎与导致神经病理性疼痛的成分有关，如神经损伤的程度和慢性疼痛的既往史。有趣的是，幻肢运动似乎对这两种现象都有保护作用。
