Pain
-
Comparative Study
Intramuscular injection of tumor necrosis factor-alpha induces muscle hyperalgesia in rats.
The role of proinflammatory cytokines in neuropathic and inflammatory pain is well established. Recent studies suggest that cytokines such as tumor necrosis factor-alpha (TNF) may also be involved in the development of muscle pain. To investigate the pathophysiology of intramuscular TNF, exogenous TNF (0.1-10 microg), formalin (9%) or vehicle was injected into the gastrocnemius or biceps brachii muscles of rats. ⋯ TNF and formalin evoked intramuscular upregulation of CGRP and NGF, whereas PGE2 was increased exclusively after TNF injection. These findings allow us to speculate that endogenous TNF may play a role in the development of muscle hyperalgesia. Targeting proinflammatory cytokines might be beneficial for the treatment of musculoskeletal pain syndromes.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Negative affect: effects on an evaluative measure of human pain.
Prior work indicates that exposure to fear-inducing shock inhibits finger-withdrawal to radiant heat in humans (hypoalgesia), whereas anxiety induced by threat of shock enhances reactivity (hyperalgesia; Pain 84 (2000) 65-75). Although finger-withdrawal latencies are thought to reflect changes in pain sensitivity, additional measures of pain are needed to determine whether pain perception is altered. The present study examined the impact of negative affect on visual analog scale (VAS) ratings of fixed duration thermal stimuli. ⋯ Results suggest that both negative affect manipulations reduced pain. Manipulation checks indicated that the emotion-induction treatments induced similar levels of fear but with different arousal levels. Potential mechanisms for affect induced changes in pain are discussed.
-
Case Reports
Pulsed radiofrequency treatment of the Gasserian ganglion in patients with idiopathic trigeminal neuralgia.
Pulsed radiofrequency treatment has been described as a minimal invasive alternative to radiofrequency thermocoagulation for the management of chronic pain syndromes. We present here our first five high-risk patients with idiopathic trigeminal neuralgia who were treated with pulsed radiofrequency after multidisciplinary assessment; with a mean follow-up of 19.2 months (range 10-26). ⋯ An excellent long-term effect was achieved in three of the five patients, a partial effect in one patient and a short-term effect in one patient. No neurological side effects or complications were reported.
-
Comparative Study
Facial arthralgia and myalgia: can they be differentiated by trigeminal sensory assessment?
Heat and electrical detection thresholds were assessed in 72 patients suffering from painful temporomandibular disorder. Employing widely accepted criteria, 44 patients were classified as suffering from temporomandibular joint (TMJ) arthralgia (i.e. pain originating from the TMJ) and 28 from myalgia (i.e. pain originating from the muscles of mastication). Electrical stimulation was employed to assess thresholds in large myelinated nerve fibers (Abeta) and heat application to assess thresholds in unmyelinated nerve fibers (C). ⋯ Following arthrocentesis, mean electrical detection threshold ratios in the AUT territory were significantly elevated from 0.64+/-0.06 to 0.99+/-0.04 indicating resolution of the hypersensitivity (paired t-test, P=0.001). In conclusion, large myelinated fiber hypersensitivity is found in the skin overlying TMJs with clinical pain and pathology but is not found in controls. In patients with muscle-related facial pain there was significant elevation of the electrical detection threshold in the AUT region.
-
Attachment theory and research suggest that patterns of interpersonal relationships may be important determinants of illness behavior, care seeking, and treatment response in individuals with chronic health problems, including chronic pain. Attachment styles have been shown to be associated with psychological adjustment in the context of chronic illness, but little research has been conducted so far examining these relationships in patients with chronic pain. ⋯ Preoccupied attachment style was associated with greater than weekly pain-related visits at 12 months follow-up, even after controlling for depression, catastrophizing and pre-treatment pain-related health care utilization. The findings suggest that attachment style may be a useful construct for examining factors affecting adjustment and treatment response of patients with chronic pain.