Valencia Carolina, Kindler Lindsay L, Fillingim Roger B, George Steven Z
BMC Musculoskelet Disord. 2013 Jun 10;14:182. doi: 10.1186/1471-2474-14-182.
Several chronic pain populations have demonstrated decreased conditioned pain modulation (CPM). However there is still a need to investigate the stability of CPM paradigms before the measure can be recommended for implementation. The purpose of the present study was to assess whether shoulder pain intensity and gender influence CPM stability within and between sessions.
This study examined two different musculoskeletal pain models, clinical shoulder pain and an experimental model of shoulder pain induced with eccentric exercise in healthy participants. Patients in the clinical cohort (N = 134) were tested before surgery and reassessed 3 months post-surgery. The healthy cohort (N = 190) was examined before inducing pain at the shoulder, and 48 and 96 hours later.
Our results provide evidence that 1) stability of inhibition is not related to changes in pain intensity, and 2) there are sex differences for CPM stability within and between days.
Fluctuation of pain intensity did not significantly influence CPM stability. Overall, the more stable situations for CPM were females from the clinical cohort and males from the healthy cohort.
几个慢性疼痛群体已表现出条件性疼痛调制（CPM）降低。然而，在推荐该测量方法用于临床实施之前，仍有必要研究CPM范式的稳定性。本研究的目的是评估肩痛强度和性别是否会影响各时段内及各时段间CPM的稳定性。
本研究考察了两种不同的肌肉骨骼疼痛模型，即临床肩痛模型以及在健康参与者中通过离心运动诱发的肩痛实验模型。临床队列中的患者（N = 134）在手术前接受测试，并在术后3个月进行重新评估。健康队列（N = 190）在肩部诱发疼痛前、诱发疼痛后48小时和96小时接受检查。
我们的结果表明：1）抑制的稳定性与疼痛强度的变化无关；2）各天内及各天间CPM的稳定性存在性别差异。
疼痛强度的波动并未显著影响CPM的稳定性。总体而言，CPM更稳定的情况见于临床队列中的女性和健康队列中的男性。
