The journal of pain : official journal of the American Pain Society
-
It is widely believed that cortical changes are a consequence of longstanding neuropathic pain (NP). In this article, we demonstrate that NP in individuals with subacute spinal cord injury (SCI) has characteristic electroencephalography markers (EEG) that precede the onset of pain. EEG was recorded in a relaxed state and during motor imagination tasks in 10 able-bodied participants and 31 patients with subacute SCI (11 with NP, 10 without NP, and 10 who had pain develop within 6 months of EEG recording). ⋯ Clinical Trial Registration Number: NCT02178917 PERSPECTIVE: We demonstrate that brain activity in patients with subacute SCI reveals both early markers and predictors of NP, which may manifest before sensory discomfort. These markers and predictors may complement known sensory phenotypes of NP. They may exist in other patient groups suffering from NP of central origin.
-
This focus article addresses the issue of the proper use of terminology in pain research. A review and some revisions of the definitions of pain and nociception in relation to consciousness are presented. From a behavioral viewpoint, it is argued that pain is a conscious assessment of the failure of the organism to protect the body from injury (actual or potential), whereas continuously ongoing subconscious/preconscious nociceptive processes protect the body from injuries. ⋯ The title of the bill itself does not make sense if we adhere to the strict definitions commonly accepted in our field. Thus this article concludes with a plea to properly constrain the narrative with which we describe our research and minimize potential abuse of the science of pain for political interests. Perspective:The focus article goes over the classic definitions of pain and nociception, incorporates novel concepts recently advanced as to their functional differentiation, and is a plea for our research and clinical society to adhere to the proper use of these terms to minimize misinterpretation by society at large.
-
Pain is significantly impacted by the increasing epidemic of obesity and the metabolic syndrome. Our understanding of how these features impact pain is only beginning to be developed. Herein, we have investigated how small genetic differences among C57BL/6 mice from 2 different commercial vendors lead to important differences in the development of high-fat diet-induced mechanical sensitivity. ⋯ PERSPECTIVE: Obesity and the metabolic syndrome play an important role in pain. This study identifies key differences in the response to a high-fat diet among substrains of C57BL/6 mice and differences in intrinsic physical activity that may influence pain sensitivity. The results emphasize physical activity as a powerful modulator of obesity-related pain sensitivity.
-
Changes in excitability of the sensorimotor cortex have been demonstrated in clinical musculoskeletal pain, although the timing is unknown. Eccentric exercise provokes delayed-onset muscle soreness providing a model to study the temporal profile of sensorimotor cortical plasticity during progressively developing muscle soreness. Twelve healthy participants performed eccentric exercise of the wrist extensors. ⋯ A decrease in the ECR pressure pain thresholds was correlated (P < .027) with an increase in the P45 amplitude at a centroparietal recording site. PERSPECTIVE: These novel data demonstrate that the somatosensory cortical excitability may be affected by muscle soreness developing over days in parallel with a deficit in the motor system. Cortical neuroplasticity may thus develop in the subacute phase and be relevant for understanding neural adaptation in the transition from acute to persistent pain.
-
This study aims to assess the effectiveness of psychosocial techniques to decrease postoperative pain and improve perioperative clinical care in orthopedic surgery. A systematic review and meta-analysis was performed to evaluate the effects of psychosocial methods among adults undergoing orthopedic surgeries. The systematic review included both randomized and nonrandomized trials, but only randomized controlled clinical trials (RCTs) were included in the meta-analysis. ⋯ The results indicate that psychosocial interventions, especially patient education and relaxation training, may reduce perioperative side effects and improve recovery in patients undergoing orthopedic procedures, but the quality of evidence is generally low. More well-powered, high-quality studies are needed to increase confidence. PERSPECTIVE: In this meta-analysis of RCTs in orthopedic surgeries, significant benefits in postoperative pain, perioperative anxiety, and recovery were found, suggesting that psychosocial interventions, especially patient education and relaxation techniques, are useful in improving clinical care.