Advances in Non-Invasive Neuromodulation.

PURPOSE OF REVIEW: Pain medicine is rapidly expanding. The gap in treatment for patients with chronic pain in between traditional conservative therapy and major invasive surgery is closing. Neuromodulation is one therapeutic area that has continued to show promise for treatment of chronic pain. Our aim is to review updates in non-invasive neuromodulation (NIN) techniques as an adjunct for various chronic pain conditions. RECENT FINDINGS: Overall, the literature suggests that NIN techniques such as tCDS, TMS, TENS, tVNS, and HIFUS/LIFUS have utility in treating various types of chronic pain and have a promising future. There is a better understanding of the mechanistic basis for pain relief from NIN, as well as refinement in technology improving NIN therapy success. Future studies will need to focus on continuing to refine protocols for optimal benefit from NIN as well as implementing larger RCTs to improve the quality of data being generated in the field.

Effects of aging and exercise training on the dynamics of vasoconstriction in skeletal muscle resistance vessels.

It is unknown whether aging or exercise training affect the dynamics of arteriolar vasoconstriction. PURPOSE: We hypothesized that old age will slow, and exercise training will speed, the dynamics of skeletal muscle arteriolar vasoconstriction in resistance vessels of aged rats. METHOD: Young (6 month old) and aged (24 month old) male Fischer-344 rats were assigned to sedentary (Sed: n = 6/age group) or exercise-trained (ET: n = 5 aged and 6 young; via treadmill running for 10-12 weeks) groups. After completion of training, arterioles from the red portion of the gastrocnemius muscle were removed, cannulated, and exposed to 10-4 M norepinephrine (NE) or 20 mM caffeine. Changes in luminal diameter were recorded for analysis of constrictor dynamics. RESULT: Old age blunted all kinetic parameters (i.e., time delay, time constant) resulting in vasoconstriction taking ~3 times as long to reach a steady state (SS) versus younger counterparts for NE (aged-sed: 15.6 ± 6.0 versus young-sed: 4.6 ± 0.5 s; P < 0.05) with a similar time course to caffeine. Exercise training resulted in a similar time to SS between age groups for NE (aged-ET: 6.8 ± 1.6 versus young-ET: 7.0 ± 0.6 s) and caffeine (aged-ET: 7.8 ± 0.6 versus young-ET: 8.6 ± 1.0 s). CONCLUSION: The results of this study demonstrate that aging blunts the rate of vasoconstriction in skeletal muscle resistance vessels to the sympathetic neurotransmitter NE due, in part, to an attenuated rate of contraction from intracellular calcium release. Further, exercise training speeds the dynamics of constriction to both NE and caffeine with old age.

Intrathecal Pumps.

Intrathecal drug delivery systems are a well-established intervention for chronic pain. The localized delivery of analgesics allows for reduced side effect profiles and pain scores in patients with chronic pain. Given their proven benefits and the development of novel intrathecal medications, intrathecal drug delivery systems are being used earlier in chronic pain management treatment pathways. Success is reliant on proper patient selection and mitigating the risks of various adverse events stemming from the implantation procedure, medications, and the device itself. This article discusses patient selection criteria, medication selection, risks, complications, supporting data, and future directions of intrathecal drug delivery systems.