Acupuncture-Induced Changes in Nociception, Measured by Pain-Related Evoked Potentials: A Pilot Mechanistic Study.

Objective: The nociceptive system has been implicated in acupuncture analgesia, although acupuncture's precise mechanism of action remains unknown. Electric pain-related evoked potentials (PREPs) have emerged as an effective and reliable electrophysiologic method for evaluation of the human nociceptive system by electric stimulation of nociceptive Aδ and C fibers. This pilot mechanistic study aims to assess the feasibility of using advanced PREP techniques together with electroacupuncture and to use PREPs to characterize acupuncture's effect on nociception. Methods: Seven healthy volunteers underwent a previously designed electroacupuncture protocol using acupoints in the legs bilaterally, which has been demonstrated to induce systemic analgesia. Advanced PREP techniques involving tripolar stimulating electrode, varying interstimulus interval, and incorporating a cognitive task during PREPs were used. PREPs were assessed before electroacupuncture, during electroacupuncture, and 30 min after electroacupuncture. Subjective pain perception in response to the PREP-related electric pain stimuli delivered to the nondominant hand was assessed on the visual analog scale (VAS) at baseline, during electroacupuncture, and 30 min postelectroacupuncture. Results: Reliable PREP N1, P1, and N2 waves were obtained from all subjects at the following average latencies: N1 = 131.5 msec, P1 = 189.4 msec, and N2 = 231.1 msec. Electroacupuncture caused a significant reduction in PREP N1P1 wave amplitudes from 25.6 to 15.4 µV (p = 0.006) and electric pain perception on the VAS-from 2.86 to 2.14 (p = 0.008), compared to baseline. These effects were sustained at 30 min postacupuncture with N1P1 wave amplitude 17.2 µV (p = 0.030) and VAS 2.28 (p = 0.030), compared to baseline. Conclusions: Electroacupuncture causes significant changes in objective nociception, measured by PREP N1P1 wave amplitudes, and in subjective nociception, measured by the VAS, and these effects are sustained for 30 min after electroacupuncture. Planned future studies will involve chronic pain populations and will aim to assess acupuncture's longer term analgesic effects.

Osteopathic approach to sacroiliac joint pain in pregnant patients.

This paper aims to provide a comprehensive review of the management of sacroiliac (SI) joint pain in pregnant patients. Although SI joint pain is highly prevalent among pregnant patients, the unique anatomy of the joint is rarely discussed in a clinical setting. This paper provides comprehensive review of the epidemiology, anatomy, alarm findings, standard treatment, osteopathic assessment, and osteopathic manipulative treatment (OMT) of the SI joint, and it provides a general and in-depth understanding of the SI joint pain in pregnant patients and its management.