Pain Management Division, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, 550 North Broadway, Baltimore, MD 21029, USA.
J Pain. 2011 Aug;12(8):859-67. doi: 10.1016/j.jpain.2011.01.009. Epub 2011 Apr 9.
Postamputation pain (PAP) affects over 60% of major limb amputees. One of the main challenges in treating PAP is the difficulty involved in identifying pain mechanism(s), which pertains to both residual limb pain (RLP) and phantom limb pain (PLP). In this study, sympathetic blocks were performed on 17 major limb amputees refractory to treatment, including 2 placebo-controlled blocks done for bilateral amputations. One hour postinjection, mean RLP scores at rest declined from 5.2 (SD 2.8) to 2.8 (SD 2.6) (P = .0002), and PLP decreased from 5.3 (SD 3.1) to 2.3 (SD 2.1) (P = .0009). By 1 week, mean pain scores for RLP and PLP were 4.3 (SD 2.9) and 4.2 (SD 3.0), respectively. Overall, 8 of 16 (50%) patients experienced ≥50% reduction in RLP 1-hour postinjection, with the beneficial effects being maintained at 1 and 8 weeks in 4 and 1 patient(s), respectively. For PLP, 8 of 15 (53%) patients obtained ≥50% decrease in pain 1-hour postblock, with these numbers decreasing to 2 patients at both 1 and 8 weeks. In the 2 bilateral amputees who received controlled injections, mean PLP and RLP at rest scores went from 4.0 and 3.3 to 4.0 and 2.5 1-hour postblock, respectively, on the placebo side. On the treatment side, mean PLP and RLP scores decreased from 7.5 and 6.5, respectively, to 0.
The results of this study suggest that sympathetic mechanisms play a role in PLP and to a lesser extent, RLP, but that blocks confer long-term benefits in only a small percentage of patients.
截肢后疼痛（PAP）影响超过 60%的主要肢体截肢者。治疗 PAP 的主要挑战之一是识别疼痛机制（涉及残肢痛（RLP）和幻肢痛（PLP））的难度。在这项研究中，对 17 名对治疗有抗药性的主要肢体截肢者进行了交感神经阻滞，包括对双侧截肢者进行的 2 次安慰剂对照阻滞。注射后 1 小时，休息时平均 RLP 评分从 5.2（SD 2.8）降至 2.8（SD 2.6）（P =.0002），PLP 从 5.3（SD 3.1）降至 2.3（SD 2.1）（P =.0009）。到第 1 周时，RLP 和 PLP 的平均疼痛评分分别为 4.3（SD 2.9）和 4.2（SD 3.0）。总体而言，注射后 1 小时，16 名患者中有 8 名（50%）的 RLP 疼痛减轻≥50%，其中 4 名和 1 名患者的获益分别在 1 周和 8 周时得以维持。对于 PLP，15 名患者中有 8 名（53%）患者在注射后 1 小时疼痛减轻≥50%，这一数字在 1 周和 8 周时分别减少到 2 名患者。在接受对照注射的 2 名双侧截肢者中，休息时平均 PLP 和 RLP 评分分别从 4.0 和 3.3 降至注射后 1 小时的 4.0 和 2.5，在安慰剂侧。在治疗侧，PLP 和 RLP 评分分别从 7.5 和 6.5 降至 0。
这项研究的结果表明，交感神经机制在 PLP 中起作用，在较小程度上在 RLP 中起作用，但阻滞在只有一小部分患者中带来长期益处。
