The journal of pain : official journal of the American Pain Society
-
Randomized Controlled Trial
Virtual reality helmet display quality influences the magnitude of virtual reality analgesia.
Immersive Virtual Reality (VR) distraction can be used in addition to traditional opioids to reduce procedural pain. The current study explored whether a High-Tech-VR helmet (ie, a 60-degree field-of-view head-mounted display) reduces pain more effectively than a Low-Tech-VR helmet (a 35-degree field-of-view head-mounted display). Using a double-blind between-groups design, 77 healthy volunteers (no patients) aged 18-23 were randomly assigned to 1 of 3 groups. Each subject received a brief baseline thermal pain stimulus, and the same stimulus again minutes later while in SnowWorld using a Low-Tech-VR helmet (Group 1), using a High-Tech-VR helmet (Group 2), or receiving no distraction (Group 3, control group). Each participant provided subjective 0-10 ratings of cognitive, sensory, and affective components of pain, and amount of fun during the pain stimulus. Compared to the Low-Tech-VR helmet group, subjects in the High-Tech-VR helmet group reported 34% more reduction in worst pain (P < .05), 46% more reduction in pain unpleasantness (P = .001), 29% more reduction in "time spent thinking about pain" (P < .05), and 32% more fun during the pain stimulus in VR (P < .05). Only 29% of participants in the Low-Tech helmet group, as opposed to 65% of participants in the High-Tech-VR helmet group, showed a clinically significant reduction in pain intensity during virtual reality. These results highlight the importance of using an appropriately designed VR helmet to achieve effective VR analgesia (see ). ⋯ Pain during medical procedures (eg, burn wound care) is often excessive. Adjunctive virtual reality distraction can substantially reduce procedural pain. The results of the present study show that a higher quality VR helmet was more effective at reducing pain than a lower quality VR helmet.
-
Randomized Controlled Trial Comparative Study
The pain quality assessment scale: assessment of pain quality in carpal tunnel syndrome.
The Neuropathic Pain Scale (NPS) is a valid measure of the pain qualities and perceived depth of neuropathic pain. However, it does not include a number of pain qualities commonly seen in some neuropathic and non-neuropathic pain conditions. To address this limitation, additional items were added to the NPS to create a 20-item measure (Pain Quality Assessment Scale, PQAS) that would be even more useful for assessing neuropathic pain and also would be used to assess pain qualities associated with non-neuropathic pain. To evaluate the responsivity of the PQAS items to pain treatment, secondary analyses were conducted on data from a trial that compared the efficacy of lidocaine patch 5% versus a single steroid injection in 40 patients with carpal tunnel syndrome. Statistically significant (P < .0025) decreases in 10 of the 20 PQAS pain descriptor ratings occurred with both treatments, and 8 ratings showed nonsignificant trends (.0025 < P < .05) for decreasing before treatment to after treatment. No significant differences were found between the 2 treatment conditions on any of the items. The results support the validity of the PQAS items for assessing the effects of pain treatment on pain qualities of carpal tunnel syndrome. ⋯ Clinical trials that include measures of pain qualities can be used to identify the effects of treatments on distinct pain qualities. Measures such as the PQAS can potentially be used to help clinicians target analgesics more efficiently.
-
Interdisciplinary rehabilitation in fibromyalgia and chronic back pain: a prospective outcome study.
This study aimed to examine short-term and mid-term course of health, biopsychosocial functional ability, and coping performance of patients with fibromyalgia (FM) or chronic back pain (BP) after participation in a standardized 4-week inpatient, interdisciplinary pain rehabilitation program. In a prospective cohort study, assessments were made by using a set of standardized, well-tested self-rating instruments and other parameters before and after the intervention up to the 6-month follow-up with standardized effect sizes (ES) and comparison to population norms. The effects of improvements in health and coping domains on pain reduction were examined by linear regression modeling. The health of the 65 FM and the 60 BP patients at baseline was far worse than expected from the norms. Improvements included ES up to 1.09 for pain, physical role performance, and mental/affective health dimensions and 0.50 in coping at discharge from the clinic. At the 6-month follow-up, all effects were consistently lower but still up to ES = 0.75. Improvements of FM and BP were equal at discharge but slightly better for the FM's mood scales at the 6-month follow-up. Physical and social function, mood, and coping were significantly associated with pain reduction. ⋯ Inpatient, structured interdisciplinary rehabilitation covering elements of cognitive and operant behavioral therapy, graded activity exercise, and adapted drug therapy revealed moderate to large short-term and mid-term improvements in physical and mental health and in the major coping dimensions as captured by comprehensive and specific assessment.
-
The activation of spinal cord microglia and astrocytes after peripheral nerve injury or inflammation contributes to behavioral hypersensitivity. The contribution of spinal cord glia to mechanical hypersensitivity after hind paw incision has not been investigated previously. Male Sprague-Dawley rats underwent a unilateral plantar hind paw incision, and the development of mechanical hypersensitivity was assessed by using von Frey filaments. The activation of spinal cord microglia and astrocytes was measured 1, 2, 3, and 5 days after hind paw incision by using immunohistochemistry. The glial activation inhibitor, fluorocitrate, was administered intrathecally 24 hours after hind paw incision to determine glial involvement in mechanical hypersensitivity. Hind paw incision induced an activation of spinal astrocytes ipsilateral to incision within 24 hours. Both microglia and astrocytes reached a maximum activation 3 days after hind paw incision. Fluorocitrate produced a dose-dependent reduction in mechanical hypersensitivity when administered 24 hours after hind paw incision. Spinal cord glial activation contributes to the mechanical hypersensitivity that develops after hind paw incision. ⋯ Hind paw incision produces mechanical hypersensitivity that can be alleviated with the inhibition of spinal cord glia. Our results suggest that the activation of spinal cord astrocytes within 24 hours of incision contributes to mechanical hypersensitivity. Therefore, spinal cord astrocytes might represent a novel target for the treatment of postoperative pain.